WO2020163777A1

WO2020163777A1 - Aromatic hyper branched polyaryletherketone-based membranes for high temperature gas separation

Info

Publication number: WO2020163777A1
Application number: PCT/US2020/017313
Authority: WO
Inventors: Theo Dingemans; Wouter VOGEL
Original assignee: The University Of North Carolina At Chapel Hill; Tu Delft
Priority date: 2019-02-08
Filing date: 2020-02-07
Publication date: 2020-08-13

Abstract

The invention generally relates to hyperbranched polymers and hyperbranched polymer networks and methods of making and using same. Specifically, the disclosed hyperbranched polymer networks can be incorporated into membranes, which can be useful in, for example, high temperature gas separation. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.

Description

AROMATIC HYPER BRANCHED POLYARYLETHERKETONE-BASED MEMBRANES FOR HIGH TEMPERATURE GAS SEPARATION

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This Application claims the benefit of U.S. Application No. 62/803,238, filed on February 08, 2019, the contents of which are hereby incorporated by reference in their entirety.

BACKGROUND

[0002] Commercially available poly(aryletherketone)s (PAEKs) such as

poly(etheretherketone) (PEEK) and poly(etherketoneketone) (PEKK) exhibit good thermomechanical properties together with excellent stability towards a wide range of solvents and gases. In principle, the PAEK backbone is ideal for high temperature gas separation membranes (e.g. , separating N2 from Eh or CO2 from Eh); however, the maximum use temperature of PAEKs is too low together with their high degree of crystallinity, typical for this class of polymers, precludes their use in high temperature (e.g., >150 °C) gas separation membranes because their glass transition temperature (i.e., softening temperature) is around 150 °C and the crystallinity slows down permeability. In addition, the poor solubility of aromatic PAEKs makes casting thin membranes from solution difficult, if not impossible. Therefore, there remains a need for soluble, reactive hyperbranched

poly(aryletherketone)s that can be readily processed into thin films for use in, for example, high temperature gas separation. These needs and others are met by the present invention.

SUMMARY

[0003] In accordance with the purpose(s) of the invention, as embodied and broadly described herein, the invention, in one aspect, relates to hyperbranched polymers and hyperbranched polymer networks, methods of making same, and methods of using same in, for example, gas separation membranes.

[0004] Disclosed are hyperbranched polymers having a poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group.

[0005] Also disclosed are hyperbranched polymers having a poly(aryletherketone) backbone and at least one residue having an end group selected from the group consisting of phenylacetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine, wherein the end group is present in an amount of from about 5 mol% to about 40 mol%.

[0006] Also disclosed are hyperbranched polymer networks comprising a disclosed hyperbranched polymer, wherein the hyperbranched polymer network is crosslinked via the phenylacetylene end group.

[0007] Also disclosed are methods for making a disclosed hyperbranched polymer, the method comprising: (a) providing a hyperbranched poly(aryletherketone) having at least one halide end group; and (b) reacting the hyperbranched poly(aryletherketone) with a monomer having a phenylacetylene group.

[0008] Also disclosed are methods for making a disclosed hyperbranched polymer network, the method comprising crosslinking a disclosed hyperbranched polymer.

[0009] Also disclosed are articles comprising a disclosed hyperbranched polymer network, wherein the article is selected from a polymer film, a thermoset, a polymer coating, an adhesive, and a thermoplastic resin.

[0010] Also disclosed are membranes having a support and a polymer layer comprising a hyperbranched polymer network, wherein the polymer layer has a thickness of from about 100 nm to about 2 pm, wherein the hyperbranched polymer network comprises a

hyperbranched polymer, wherein the hyperbranched polymer comprises a

poly(aryletherketone) backbone and at least one residue having an end group, and wherein the hyperbranched polymer is crosslinked via the end group.

[0011] Also disclosed are methods for making a disclosed membrane. Thus, in various aspects, disclosed are methods for making a disclosed membrane, the method comprising the steps of: (a) providing a composition comprising the hyperbranched polymer network; and (b) coating the composition onto the support; thereby forming the membrane.

[0012] Also disclosed are methods for separating a first gas species from a second gas species in a gas mixture, wherein the first gas species is different from the second gas species, the method comprising the step of passing the gas mixture through or alongside a disclosed membrane.

[0013] While aspects of the present invention can be described and claimed in a particular statutory class, such as the system statutory class, this is for convenience only and one of skill in the art will understand that each aspect of the present invention can be described and claimed in any statutory class. Unless otherwise expressly stated, it is in no way intended that any method or aspect set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not specifically state in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including matters of logic with respect to arrangement of steps or operational flow, plain meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying figures, which are incorporated in and constitute a part of this specification, illustrate several aspects and together with the description serve to explain the principles of the invention.

[0015] FIG. 1 shows representative size exclusion data of HBPAEK-69K with and without PEP end-cap.

[0016] FIG. 2 shows representative Raman spectra of neat HBPAEK-69K and PEP end- capped HBPAEK-69K series.

[0017] FIG. 3 shows representative ¹⁹F NMR spectra of the neat and PEP end-capped HBPAEK-69K.

[0018] FIG. 4 shows representative differential scanning calorimetry (DSC) scans of the first heat of HBPAEK-69 and PEP end-capped HBPAEK-69K.

[0019] FIG. 5 shows representative rheology curves of HBPAEK-69K and HBPAEK- 69K with 10, 20, and 40% PEP.

[0020] FIG. 6 shows representative thermogravimetric analysis results for HBPAEK- 69K and HBPAEK-69K with 10, 20, and 40% PEP cured at 350 °C for 1 h.

[0021] FIG. 7 shows representative images of cast HBPAEK-69K films after curing at 350 °C.

[0022] FIG. 8A and FIG. 8B show representative data of dynamic mechanical thermal analysis of HBPAEK films.

[0023] FIG. 9A and FIG. 9B show representative storage modulus (FIG. 9A) and loss modulus (FIG. 9B) of HBPAEK-69K-20PEP.

[0024] FIG. 10A-D show representative tensile data of PEP end-capped HBPAEK-69Ks.

[0025] FIG. 11A and FIG. 11B show representative schematic representations of the response of different polymer architectures on an applied stress field. [0026] FIG. 12 shows representative images illustrating that HBPAEKs can be spin- coated on an alumina substrate and exposed to a curing profile.

[0027] FIG. 13A and FIG. 13B show representative thermal crosslink profiles as a function of temperature versus time.

[0028] FIG. 14 shows representative size exclusion chromatography (SEC) data of HBPAEK-33K, HBPAEK-28K- 10-PEP and HBPAEK-25K-20PEP in THF at a concentration of 1 mg/ml.

[0029] FIG. 15A-C show representative data illustrating weight loss as a function of temperature for HBPAEK-33K (FIG. 15A), HBPAEK-28K-10PEP (FIG. 15B), and HBPAEK-25K-20PEP (FIG. 15C).

[0030] FIG. 16 shows representative DSC curves showing the glass transition temperatures of uncross-linked HBPAEK-33K, HBP AEK-28K- 10PEP and HBPAEK-25K- 20PEP, as first heat, 20 °C/min under N2 atmosphere.

[0031] FIG. 17A and FIG. 17B show representative data illustrating the thermal behavior of HBPAEK-28K-10PEP using the 280-350 °C temperature program.

[0032] FIG. 18A and FIG. 18B show representative data illustrating the thermal behavior of HBPAEK-33K using the 280-350 °C temperature program.

[0033] FIG. 19A and FIG. 19B show representative data illustrating the thermal behavior of HBPAEK-25K-20PEP using the 280-350 °C temperature program.

[0034] FIG. 20 shows representative data illustrating the determination of data points used to calculate the linear coefficient of thermal expansion.

[0035] FIG. 21 shows representative data illustrating the change in T_g as a function of the cross-link temperature for the different HBPAEKs studied measured by in situ spectroscopic ellipsometry (SE).

[0036] FIG. 22 show representative data illustrating the change in excess free fractional volume (EFFV) as a function of the cross-link temperature for the different HBPAEKs studied measured by in situ SE.

[0037] FIG. 23 shows a simplified schematic representation of the EFFV of a polymer.

[0038] FIG. 24A-C show representative CO2 sorption (O) and desorption (□) for

HBPAEK-28K-10PEP, at pressures up to 60 bar.

[0039] FIG. 25A-C show representative CO2 sorption (O) and desorption (□) for HBPAEK-25K-20PEP, at pressures up to 60 bar. [0040] FIG. 26 shows representative data illustrating the contact angle of uncross-linked and cross-linked (temperature program 280-350 °C) HBPAEK films on silicon wafers.

[0041] FIG. 27A and FIG. 27B show representative data illustrating the relative thickness (a) and relative refractive index (b) for HBPAEK-28K-10PEP (□) and HBPAEK- 25K-20PEP (O) cross-linked at 350 °C as function of relative humidity.

[0042] FIG. 28 shows a representative schematic illustrate that HBPAEKs are spin- coated on an alumina substrate, after which they are heated to form a crosslinked network gas separation membrane.

[0043] FIG. 29 shows representative data illustrating that spin-coated HBPAEK-28K- 10PEP and HBPAEK-25K-20PEP films were cured for lh at 280 °C and lh at 350 °C.

[0044] FIG. 30A and FIG. 30B show representative data illustrating the single gas permeation results for the bare alumina membrane support.

[0045] FIG. 31 shows a representative cross-section of a scanning electron micrograph of a cross-linked HBPAEK-28K-10PEP film atop of a ceramic support.

[0046] FIG. 32 shows representative data illustrating gas permeation for uncross-linked HBPAEK-28K-10PEP (panels (a)-(c)) and cross-linked HBPAEK-28K-10PEP (lh at 280 °C and lh at 350 °C) (panels (d)-(f)).

[0047] FIG. 33 shows representative data illustrating gas permeation for uncross-linked HBPAEK-25K-20PEP (panels (a)-(c)) and cross-linked HBPAEK-25K-20PEP (lh at 280 °C and lh at 350 °C) (panels (d)-(f)).

[0048] FIG. 34 shows representative Robeson plots for CO2/CH4 (panel (a)), H2/N2

(panel (b)), H2/CO2 (panel (c)), and H2/CH4 (panel (d)) gas pairs, together with their permeabilities, obtained from the permeances measured at 50 °C.

[0049] FIG. 35A and FIG. 35B show representative data illustrating the long-term thermal stability of cured HBPAEK-28K-10PEP, kept at 200 °C.

[0050] FIG. 36A and FIG. 36B show representative Robeson plots for H2/CO2 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-28K end-capped with 10% PEP (FIG. 36A) and HBPAEK-25K end-capped with 20% PEP (FIG. 36B).

[0051] FIG. 37A and FIG. 37B show representative Robeson plots for H2/CH4 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-28K end-capped with 10% PEP (FIG. 37A) and HBPAEK-25K end-capped with 20% PEP (FIG. 37B). [0052] FIG. 38A and FIG. 38B show representative Robeson plots for H2/N2 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-28K end-capped with 10% PEP (FIG. 38A) and HBPAEK-25K end-capped with 20% PEP (FIG. 38B).

[0053] FIG. 39A and FIG. 39B show representative Robeson plots for N2/CH4 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-28K end-capped with 10% PEP (FIG. 39A) and HBPAEK-25K end-capped with 20% PEP (FIG. 39B).

[0054] FIG. 40A and FIG. 40B show representative Robeson plots for CO2/CH4 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-28K end-capped with 10% PEP (FIG. 40A) and HBPAEK-25K end-capped with 20% PEP (FIG. 40B).

[0055] FIG. 41A and FIG. 41B show representative Robeson plots for CO2/N2 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-28K end-capped with 10% PEP (FIG. 41 A) and HBPAEK-25K end-capped with 20% PEP (FIG. 41B).

[0056] Additional advantages of the invention will be set forth in part in the description that follows, and in part will be obvious from the description, or can be learned by practice of the invention. The advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

DETAILED DESCRIPTION

[0057] The present invention can be understood more readily by reference to the following detailed description of the invention and the Examples included therein.

[0058] Before the present compounds, compositions, articles, systems, devices, and/or methods are disclosed and described, it is to be understood that they are not limited to specific synthetic methods unless otherwise specified, or to particular reagents unless otherwise specified, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, example methods and materials are now described.

[0059] Throughout this application, various publications are referenced. The disclosures of these publications in their entireties are hereby incorporated by reference into this application in order to more fully describe the state of the art to which this pertains. The references disclosed are also individually and specifically incorporated by reference herein for the material contained in them that is discussed in the sentence in which the reference is relied upon. Further, the dates of publication provided herein may be different from the actual publication dates, which can require independent confirmation.

A. DEFINITIONS

[0060] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative aspects of the invention are shown. In the drawings, the relative sizes of regions or features may be exaggerated for clarity. This invention may, however, be embodied in many different forms and should not be construed as limited to the aspects set forth herein; rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0061] The disclosures of all patent references cited herein are hereby incorporated by reference to the extent they are consistent with the disclosure set forth herein. As used herein in the description of the invention and the appended claims, the singular forms“a,”“an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0062] As used in the specification and in the claims, the term“comprising” can include the aspects“consisting of’ and“consisting essentially of.”

[0063] Ranges can be expressed herein as from“about” one particular value, and/or to “about” another particular value. When such a range is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent“about,” it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as“about” that particular value in addition to the value itself. For example, if the value“10” is disclosed, then“about 10” is also disclosed. It is also understood that each unit between two particular units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0064] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the present application and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. The terminology used in the description of the invention herein is for the purpose of describing particular aspects only and is not intended to be limiting of the invention. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. In case of a conflict in terminology, the present specification is controlling.

[0065] Also as used herein,“and/or” refers to and encompasses any and all possible combinations of one or more of the associated listed items, as well as the lack of

combinations when interpreted in the alternative (“or”).

[0066] Unless the context indicates otherwise, it is specifically intended that the various features of the invention described herein can be used in any combination. Moreover, the present invention also contemplates that in various aspects of the invention, any feature or combination of features set forth herein can be excluded or omitted. To illustrate, if the specification states that a complex comprises components A, B and C, it is specifically intended that any of A, B or C, or a combination thereof, can be omitted and disclaimed.

[0067] As used herein, the terms“about” and“at or about” mean that the amount or value in question can be the value designated some other value approximately or about the same. It is generally understood, as used herein, that it is the nominal value indicated ±10% variation unless otherwise indicated or inferred. The term is intended to convey that similar values promote equivalent results or effects recited in the claims. That is, it is understood that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but can be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art. In general, an amount, size, formulation, parameter or other quantity or characteristic is“about” or“approximate” whether or not expressly stated to be such. It is understood that where“about” is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0068] References to parts by weight of a particular component in a composition, whether in the specification or subsequent claims, expresses the weight relationship between the component and any other components in the composition or article for which a part by weight is described. For example, in a composition containing 1 part by weight of component A and 2 parts by weight component B, A and B are present in a weight ratio of 1:2 and exist in this ratio regardless of whether additional components are present in the composition.

[0069] A weight percent (wt.% or wt%) of a component, unless stated specifically to the contrary, is based on the total weight of the formulation or composition in which the component is included.

[0070] As used herein, the terms“optional” or“optionally” means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0071] As used herein,“polymer network” refers to a polymer in which covalent or non- covalent (dynamic) cross-linking has occurred. Examples of polymer networks include, but are not limited to, polymer gels and elastomers.

[0072] As used herein,“overall degree of polymerization” refers to the total number of monomeric units in the branched polymer structure.

[0073] As used herein, the“linear amount of repeat units” refers to the number of monomeric units linked together in a straight chain.

B. HYPERBRANCHED POLYMERS

[0074] In one aspect, disclosed are hyperbranched polymers having a

poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group.

[0075] In one aspect, disclosed are hyperbranched polymers having a

poly(aryletherketone) backbone and at least one residue having an end group selected from the group consisting of phenylacetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine, wherein the end group is present in an amount of from about 5 mol% to about 40 mol%. In a further aspect, the end group is phenylacetylene.

[0076] In a further aspect, the polymer has at least one residue having a halide end group. Examples of halide end groups include, but are not limited to, fluoride, chloride, bromide, and iodide. Thus, various aspects, the halide end group is a fluoride end group.

[0077] In a further aspect, the hyperbranched polymer has at least one residue having a hydroxyl end group.

[0078] In a further aspect, the poly(aryletherketone) backbone is a polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a polyetherketoneketone (PEKK) backbone.

[0079] In a further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 5 mol% to about 40 mol%. In a still further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 5 mol% to about 30 mol%. In yet a further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 5 mol% to about 20 mol%. In an even further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 5 mol% to about 10 mol%. In a still further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 10 mol% to about 40 mol%. In yet a further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 20 mol% to about 40 mol%. In an even further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 30 mol% to about 40 mol%. In a still further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 10 mol% to about 30 mol%. In yet a further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 15 mol% to about 25 mol%.

[0080] In a further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is a structure represented by a formula selected from the group consisting of:

[0081] In a further aspect, the at least one occurrence of Ar^la, Ar^lb, and Ar² is a structure represented by a formula:

[0082] In a further aspect, the polymer has a degree of branching of from about 0.3 to about 0.7. In a still further aspect, the polymer has a degree of branching of from about 0.3 to about 0.6. In yet a further aspect, the polymer has a degree of branching of from about 0.3 to about 0.5. In an even further aspect, the polymer has a degree of branching of from about 0.3 to about 0.4. In a still further aspect, the polymer has a degree of branching of from about 0.4 to about 0.7. In yet a further aspect, the polymer has a degree of branching of from about 0.5 to about 0.7. In an even further aspect, the polymer has a degree of branching of from about 0.6 to about 0.7. [0083] In a further aspect, the polymer has a degree of branching of about 0.3. In a still further aspect, the polymer has a degree of branching of about 0.4. In yet a further aspect, the polymer has a degree of branching of about 0.5. In an even further aspect, the polymer has a degree of branching of about 0.6. In a still further aspect, the polymer has a degree of branching of about 0.7.

[0084] In a further aspect, the polymer is amorphous.

[0085] In a further aspect, the polymer has a glass transition temperature (T ) of from about 130 °C to about 200 °C. In a still further aspect, the polymer has a glass transition temperature (T_g) of from about 130 °C to about 180 °C. In yet a further aspect, the polymer has a glass transition temperature (T ) of from about 130 °C to about 160 °C. In an even further aspect, the polymer has a glass transition temperature (T ) of from about 130 °C to about 140 °C. In a still further aspect, the polymer has a glass transition temperature (T ) of from about 140 °C to about 200 °C. In yet a further aspect, the polymer has a glass transition temperature (T ) of from about 150 °C to about 200 °C. In an even further aspect, the polymer has a glass transition temperature (T ) of from about 160 °C to about 200 °C. In a still further aspect, the polymer has a glass transition temperature (T ) of from about 140 °C to about 180 °C. In yet a further aspect, the polymer has a glass transition temperature (T ) of from about 150 °C to about 170 °C.

[0086] In a further aspect, the polymer is at least 80% soluble at a temperature of from about 20 °C to about 25 °C in a solvent selected from tetrahydrofuran, chloroform, and N- methylpyrrolidinone. In a still further aspect, the polymer is at least 85% soluble at a temperature of from about 20 °C to about 25 °C in a solvent selected from tetrahydrofuran, chloroform, and N-methylpyrrolidinone. In yet a further aspect, the polymer is at least 90% soluble at a temperature of from about 20 °C to about 25 °C in a solvent selected from tetrahydrofuran, chloroform, and N-methylpyrrolidinone. In an even further aspect, the polymer is at least 95% soluble at a temperature of from about 20 °C to about 25 °C in a solvent selected from tetrahydrofuran, chloroform, and N-methylpyrrolidinone.

[0087] In a further aspect, the polymer has an excess free fractional volume (EFFV) of up to about 10%. In a still further aspect, the polymer has an excess free fractional volume

(EFFV) of up to about 9%. In yet a further aspect, the polymer has an excess free fractional volume (EFFV) of up to about 8%. In an even further aspect, the polymer has an excess free fractional volume (EFFV) of up to about 7%. In a still further aspect, the polymer has an excess free fractional volume (EFFV) of up to about 6%. In yet a further aspect, the polymer has an excess free fractional volume (EFFV) of up to about 5%. [0088] In a further aspect, the poly(aryletherketone) backbone is a polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a polyetherketoneketone (PEKK) backbone, the at least one occurrence of Ar^la, Ar^lb, and Ar² is a structure represented by a formula:

the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of about 10 mol%.

[0089] In a further aspect, the end group is present in an amount of from about 5 mol% to about 40 mol%. In a still further aspect, the end group is present in an amount of from about 5 mol% to about 30 mol%. In yet a further aspect, the end group is present in an amount of from about 5 mol% to about 20 mol%. In an even further aspect, the end group is present in an amount of from about 5 mol% to about 10 mol%. In a still further aspect, the end group is present in an amount of from about 10 mol% to about 40 mol%. In yet a further aspect, the end group is present in an amount of from about 20 mol% to about 40 mol%. In an even further aspect, the end group is present in an amount of from about 30 mol% to about 40 mol%. In a still further aspect, the end group is present in an amount of from about 10 mol% to about 30 mol%. In yet a further aspect, the end group is present in an amount of from about 15 mol% to about 25 mol%.

[0090] In a further aspect, the end group is present in an amount of about 5 mol%. In a still further aspect, the end group is present in an amount of about 10 mol%. In yet a further aspect, the end group is present in an amount of about 15 mol%. In an even further aspect, the end group is present in an amount of about 20 mol%. In a still further aspect, the end group is present in an amount of about 25 mol%. In yet a further aspect, the end group is present in an amount of about 30 mol%. In an even further aspect, the end group is present in an amount of about 35 mol%. In a still further aspect, the end group is present in an amount of about 40 mol%.

1. STRUCTURE

[0091] In one aspect, disclosed are hyperbranched polymers having a

poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group, wherein the hyperbranched polymer has repeating units having a structure represented by a formula:

wherein n is the overall degree of polymerization and wherein n is an integer selected from 10-300; wherein R^x is selected from the group consisting of halogen and -OH; and wherein each of Ar^la and Ar^lb is independently selected from the group consisting of 6-membered aryl substituted with a phenylacetylene group, 6-membered heteroaryl substituted with a phenylacetylene group, and a structure represented by a formula:

wherein each occurrence of R^la and R^lb is selected from halogen and -OAr²; and wherein each occurrence of Ar² is independently selected from the group consisting of 6-membered aryl and 6-membered heteroaryl and is substituted with a phenylacetylene group, provided at least one occurrence of Ar^la and Ar^lb is 6-membered aryl substituted with a phenylacetylene group or 6-membered heteroaryl substituted with a phenylacetylene group, or at least one occurrence of R^la and R^lb is -OAr².

[0092] In a further aspect, n is the overall degree of polymerization or the linear amount of repeat units. Without wishing to be bound by theory, the disclosed hyperbranched polymers are a mix of linear and branched units as a result of the random displacement of the end groups during polymerization (i.e., either one or both end groups can be displaced). Thus, in various aspects, n is the overall degree of polymerization. In a still further aspect, is an integer selected from about 10 to about 300, about 10 to about 250, about 10 to about 200, about 10 to about 150, about 10 to about 100, about 10 to about 50, about 10 to about 25, about 25 to about 300, about 50 to about 300, about 100 to about 300, about 150 to about 300, about 200 to about 300, about 250 to about 300, about 25 to about 250, about 50 to about 200, or about 100 to about 150. In yet a further aspect, n is the linear amount of repeat units.

[0093] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[0094] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[0095] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[0096] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[0097] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[0098] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[0099] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

[00100] In a further aspect, the hyperbranched polymer has repeating units having a structure represented by a formula:

a. R^x GROUPS

[00101] In one aspect, R^x is selected from the group consisting of halogen and -OH. In a further aspect, R^x is selected from the group consisting of -F, -Cl, and -OH. In a still further aspect, R^x is selected from the group consisting of-F and -OH. In yet a further aspect, R^x is selected from the group consisting of -Cl and -OH.

[00102] In a further aspect, R^x is selected from the group consisting of halogen. In a still further aspect, R^x is selected from the group consisting of -F and -Cl. In yet a further aspect, R^x is -Cl. In an even further aspect, R^x is -F.

[00103] In a further aspect, R^x is -OH. b. R^lA AND R^lB

[00104] In one aspect, each occurrence of R^la and R^lb is selected from halogen and -OAr². In a further aspect, each occurrence of R^la and R^lb is selected from -F, -Cl, and -OAr². In a still further aspect, each occurrence of R^la and R^lb is selected from -F and -OAr². In yet a further aspect, each occurrence of R^la and R^lb is selected from -Cl and -OAr².

[00105] In a further aspect, each occurrence of R^la and R^lb is halogen. In a still further aspect, each occurrence of R^la and R^lb is selected from -F and -Cl. In yet a further aspect, each occurrence of R^la and R^lb is -Cl. In an even further aspect, each occurrence of R^la and R^lb is -F.

[00106] In a further aspect, at least one occurrence of R^la and R^lb is halogen. In a still further aspect, at least one occurrence of R^la and R^lb is selected from -F and -Cl. In yet a further aspect, at least one occurrence of R^la and R^lb is -Cl. In an even further aspect, at least one occurrence of R^la and R^lb is -F.

[00107] In a further aspect, at least one occurrence of R^la and R^lb is -OAr². c. AR^1A AND AR^1B

[00108] In one aspect, each of Ar^la and Ar^lb is independently selected from the group consisting of 6-membered aryl substituted with a phenylacetylene group, 6-membered heteroaryl substituted with a phenylacetylene group, and a structure represented by a formula:

[00109] In a further aspect, each of Ar^la and Ar^lb is the same. In a still further aspect, each of Ar^la and Ar^lb is different. [00110] In a further aspect, each of Ar^la and Ar^lb is independently selected from the group consisting of 6-membered aryl substituted with a phenylacetylene group and 6-membered heteroaryl substituted with a phenylacetylene group. In a still further aspect, each of Ar^la and Ar^lb is independently selected from the group consisting of 6-membered aryl inela- substituted with a phenylacetylene group, 6-membered aryl /?ara-substituted with a phenylacetylene group, 6-membered heteroaryl meto-substituted with a phenylacetylene group, and 6-membered heteroaryl /?ara-substituted with a phenylacetylene group. In yet a further aspect, each of Ar^la and Ar^lb is independently selected from the group consisting of 6- membered aryl /?ara-substituted with a phenylacetylene group and 6-membered heteroaryl /Mra-substituted with a phenylacetylene group.

[00111] In a further aspect, one of Ar^la and Ar^lb is selected from the group consisting of 6- membered aryl substituted with a phenylacetylene group and 6-membered heteroaryl substituted with a phenylacetylene group. In a still further aspect, one of Ar^la and Ar^lb is selected from the group consisting of 6-membered aryl me to-substituted with a

phenylacetylene group, 6-membered aryl /?ara-substituted with a phenylacetylene group, 6- membered heteroaryl meto-substituted with a phenylacetylene group, and 6-membered heteroaryl /«/ra-substituted with a phenylacetylene group. In yet a further aspect, one of Ar^la and Ar^lb is selected from the group consisting of 6-membered aryl /?ara-substituted with a phenylacetylene group and 6-membered heteroaryl /?ara-substituted with a phenylacetylene group.

[00112] In a further aspect, one of Ar^la and Ar^lb is 6-membered aryl substituted with a phenylacetylene group. In a still further aspect, one of Ar^la and Ar^lb is selected from the group consisting of 6-membered aryl meto-substituted with a phenylacetylene group and 6- membered aryl /?ara-substituted with a phenylacetylene group. In yet a further aspect, one of Ar^la and Ar^lb is 6-membered aryl /?ara-substituted with a phenylacetylene group.

[00113] In a further aspect, one of Ar^la and Ar^lb is a structure represented by a formula selected from the group consisting of:

[00114] In a further aspect, one of Ar^la and Ar^lb is a structure represented by a formula:

[00115] In a further aspect, one of Ar^la and Ar^lb is 6-membered heteroaryl substituted with a phenylacetylene group. Examples of 6-membered heteroaryls include, but are not limited to, pyridazinyl, pyrimidinyl, pyrazinyl, and pyridinyl. Thus, in a still further aspect, one of Ar^la and Ar^lb is selected from the group consisting of 6-membered heteroaryl meta- substituted with a phenylacetylene group and 6-membered heteroaryl /Mra-substituted with a phenylacetylene group. In yet a further aspect, one of Ar^la and Ar^lb is 6-membered heteroaryl /Mra-substituted with a phenylacetylene group.

[00116] In a further aspect, one of Ar^la and Ar^lb is pyridinyl substituted with a

phenylacetylene group. In a still further aspect, one of Ar^la and Ar^lb is selected from the group consisting of pyridinyl meto-substituted with a phenylacetylene group and pyridinyl /Mra-substituted with a phenylacetylene group. In yet a further aspect, one of Ar^la and Ar^lb is pyridinyl /?ara-substituted with a phenylacetylene group.

[00117] In a further aspect, one of Ar^la and Ar^lb is a structure represented by a formula:

[00118] In a still further aspect, one of Ar^la and Ar^lb is a structure represented by a formula:

[00119] In a further aspect, one of Ar^la and Ar^lb is a structure represented by a formula:

[00120] In a further aspect, one of Ar^la and Ar^lb is 6-membered aryl /Mra-substituted with a phenylacetylene group and one of Ar^la and Ar^lb is a structure represented by a formula:

d. AR²

[00121] In one aspect, each occurrence of Ar² is independently selected from 6-membered aryl and 6-membered heteroaryl and is substituted with a phenylacetylene group. In a further aspect, each occurrence of Ar² is independently selected from 6-membered aryl and 6- membered heteroaryl and is meto-substituted or /?ara-substituted with a phenylacetylene group. In a still further aspect, each occurrence of Ar² is independently selected from 6- membered aryl and 6-membered heteroaryl and is /?ara-substituted with a phenylacetylene group.

[00122] In a further aspect, each occurrence of Ar² is independently selected from 6- membered aryl substituted with a phenylacetylene group. In a still further aspect, each occurrence of Ar² is independently selected from 6-membered aryl meto-substituted or para- substituted with a phenylacetylene group. In yet a further aspect, each occurrence of Ar² is 6- membered aryl /?ara-substituted with a phenylacetylene group.

[00123] In a further aspect, each occurrence of Ar² is independently selected from 6- membered heteroaryl substituted with a phenylacetylene group. Examples of 6-membered heteroaryls include, but are not limited to, pyridazinyl, pyrimidinyl, pyrazinyl, and pyridinyl. Thus, in a still further aspect, each occurrence of Ar² is independently selected from 6- membered heteroaryl meto-substituted or /?ara-substituted with a phenylacetylene group. In yet a further aspect, each occurrence of Ar² is 6-membered heteroaryl /Mra-substituted with a phenylacetylene group.

[00124] In a further aspect, each occurrence of Ar² is independently selected from pyridinyl substituted with a phenylacetylene group. In a still further aspect, each occurrence of Ar² is independently selected from pyridinyl meto-substituted or /?ara-substituted with a phenylacetylene group. In yet a further aspect, each occurrence of Ar² is pyridinyl para- substituted with a phenylacetylene group. [00125] In a further aspect, at least one occurrence of Ar² is a structure represented by a formula selected from the group consisting of:

[00126] In a further aspect, at least one occurrence of Ar² is a structure represented by a formula:

C. HYPERBRANCHED POLYMER NETWORKS

[00127] In one aspect, disclosed are hyperbranched polymer networks comprising a disclosed hyperbranched polymer, wherein the hyperbranched polymer network is crosslinked via the phenylacetylene end group. Thus, in various aspects, disclosed are hyperbranched polymer networks comprising a hyperbranched polymer having a

poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group, wherein the hyperbranched polymer network is crosslinked via the phenylacetylene end group. In various further aspect, disclosed are hyperbranched polymer networks comprising a hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having an end group selected from the group consisting of phenylacetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine, wherein the end group is present in an amount of from about 5 mol% to about 40 mol%, wherein the hyperbranched polymer network is crosslinked via the phenylacetylene end group.

[00128] In a further aspect, disclosed are hyperbranched polymer networks comprising a hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group, wherein the hyperbranched polymer has repeating units having a structure represented by a formula:

wherein each occurrence of R^la and R^lb is selected from halogen and -OAr²; and wherein each occurrence of Ar² is independently selected from the group consisting of 6-membered aryl and 6-membered heteroaryl and is substituted with a phenylacetylene group, provided at least one occurrence of Ar^la and Ar^lb is 6-membered aryl substituted with a phenylacetylene group or 6-membered heteroaryl substituted with a phenylacetylene group, or at least one occurrence of R^la and R^lb is -OAr², wherein the hyperbranched polymer network is crosslinked via the phenylacetylene end group.

[00129] Without wishing to be bound by theory, reactive functionalities for crosslinking hyperbranched poly(aryletherketone)s (HBPAEKs) include, for example, phenylethynyl, or phenylacetylene. The phenyl-triple bond functionality is part of a list of thermally curable end-groups (Iqbal, M. All-aromatic liquid crystal thermosets and composites thereof. PhD Thesis (TU Delft, 2010). The triple bond can thermally rearrange and form free radicals at T >300 °C, and the free radicals in turn can recombine, /. e.. chain extend or crosslink without generating volatiles (Roberts, C. C., Apple, T. M. & Wnek, G. E. Curing chemistry of phenylethynyl-terminated imide oligomers: Synthesis ofl3C-labeled oligomers and solid- state NMR studies. J. Polym. Sci. Part A Polym. Chem. 38, 3486-3497 (2000)). Proposed after cure structures include, amongst others, alkenes (f=2) and cyclotrimerized (f=3 and f=4) products. This end-group is also known for providing ductile high T_g thermoset resins, /. e.. PETI-5 (Hergenrother, P. ., Connell, J. . & Smith, J. . Phenylethynyl containing imide oligomers. Polymer (Guildf). 41, 5073-5081 (2000)). The phenyl ethynyl groups at the periphery of the globules will be responsible for connecting adjacent globules. A complete substitution of all fluorine groups for PEP groups, as reported by Jiang et al, is envisioned to be unnecessary and probably results in an over-crossbnked (britle) network (Jiang, H., Su, W., Mather, P. T. & Bunning, T. J. Rheology of highly swollen chitosan/polyacrylate hydrogels).

[00130] In a further aspect, the hyperbranched polymer network has a crosslinking density of from about 50 mol/m³ to about 90 mol/m³. In a still further aspect, the hyperbranched polymer network has a crosslinking density of from about 50 mol/m³ to about 80 mol/m³. In yet a further aspect, the hyperbranched polymer network has a crosslinking density of from about 50 mol/m³ to about 70 mol/m³. In an even further aspect, the hyperbranched polymer network has a crosslinking density of from about 50 mol/m³ to about 60 mol/m³. In a still further aspect, the hyperbranched polymer network has a crosslinking density of from about 60 mol/m³ to about 90 mol/m³. In yet a further aspect, the hyperbranched polymer network has a crosslinking density of from about 70 mol/m³ to about 90 mol/m³. In an even further aspect, the hyperbranched polymer network has a crosslinking density of from about 80 mol/m³ to about 90 mol/m³. In a still further aspect, the hyperbranched polymer network has a crosslinking density of from about 60 mol/m³ to about 80 mol/m³. In yet a further aspect, the hyperbranched polymer network has a crosslinking density of from about 65 mol/m³ to about 75 mol/m³.

[00131] In a further aspect, the hyperbranched polymer network has a crosslinking density of from about 55 mol/m³ to about 80 mol/m³. In a still further aspect, the hyperbranched polymer network has a crosslinking density of from about 55 mol/m³ to about 75 mol/m³. In yet a further aspect, the hyperbranched polymer network has a crosslinking density of from about 55 mol/m³ to about 65 mol/m³. In an even further aspect, the hyperbranched polymer network has a crosslinking density of from about 65 mol/m³ to about 80 mol/m³. In a still further aspect, the hyperbranched polymer network has a crosslinking density of from about 75 mol/m³ to about 80 mol/m³.

D. METHODS OF MAKING HYPERBRANCHED POLYMERS AND HYPERBRANCHED

POLYMER NETWORKS

[00132] In one aspect, disclosed are methods for making a disclosed hyperbranched polymer. Thus, in various aspects, disclosed are methods for making a disclosed hyperbranched polymer, the method comprising: (a) providing a hyperbranched poly(aryletherketone) having at least one halide end group; and (b) reacting the

hyperbranched poly(aryletherketone) with a monomer having a phenylacetylene group.

[00133] In a further aspect, disclosed are methods for making a hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group, the method comprising: (a) providing a hyperbranched poly(aryletherketone) having at least one halide end group; and (b) reacting the hyperbranched

poly(aryletherketone) with a monomer having a phenylacetylene group.

[00134] In a further aspect, disclosed are methods for making a hyperbranched polymers having a poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group, wherein the hyperbranched polymer has repeating units having a structure represented by a formula:

wherein each occurrence of R^la and R^lb is selected from halogen and -OAr²; and wherein each occurrence of Ar² is independently selected from the group consisting of 6-membered aryl and 6-membered heteroaryl and is substituted with a phenylacetylene group, provided at least one occurrence of Ar^la and Ar^lb is 6-membered aryl substituted with a phenylacetylene group or 6-membered heteroaryl substituted with a phenylacetylene group, or at least one occurrence of R^la and R^lb is -OAr², the method comprising: (a) providing a hyperbranched poly(aryletherketone) having at least one halide end group; and (b) reacting the

[00135] In a further aspect, providing is via polymerization of a monomer having a structure selected from the group consisting of:

[00136] In a further aspect, providing is via polymerization of a monomer having a structure:

[00137] In one aspect, disclosed are methods for making a disclosed hyperbranched polymer network. Thus, in various aspects, disclosed are methods for making a disclosed hyperbranched polymer network, the method comprising crosslinking a disclosed hyperbranched polymer. In a further aspect, the disclosed hyperbranched polymer is prepared via a disclosed method.

[00138] In a further aspect, disclosed are methods for making a hyperbranched polymer network, the method comprising crosslinking a hyperbranched polymer having a

[00139] In a further aspect, disclosed are methods for making a hyperbranched polymer network, the method comprising crosslinking a hyperbranched polymer having a

[00140] In a further aspect, crosslinking is via applying heat. In a still further aspect, applying heat is applying a temperature of from about 200 °C to about 400 °C. In yet a further aspect, applying heat is applying a temperature of from about 200 °C to about 350 °C. In an even further aspect, applying heat is applying a temperature of from about 200 °C to about 300 °C. In a still further aspect, applying heat is applying a temperature of from about 200 °C to about 250 °C. In yet a further aspect, applying heat is applying a temperature of from about 250 °C to about 400 °C. In an even further aspect, applying heat is applying a temperature of from about 300 °C to about 400 °C. In a still further aspect, applying heat is applying a temperature of from about 350 °C to about 400 °C. In yet a further aspect, applying heat is applying a temperature of from about 250 °C to about 350 °C.

[00141] In a further aspect, applying heat is applying a temperature gradient ranging from about 200 °C to about 400 °C. In a still further aspect, applying heat is applying a temperature gradient ranging from about 200 °C to about 350 °C. In yet a further aspect, applying heat is applying a temperature gradient ranging from about 200 °C to about 300 °C. In an even further aspect, applying heat is applying a temperature gradient ranging from about 200 °C to about 250 °C. In a still further aspect, applying heat is applying a temperature gradient ranging from about 250 °C to about 400 °C. In yet a further aspect, applying heat is applying a temperature gradient ranging from about 300 °C to about 400 °C. In an even further aspect, applying heat is applying a temperature gradient ranging from about 350 °C to about 400 °C. In a still further aspect, applying heat is applying a temperature gradient ranging from about 250 °C to about 350 °C.

E. ARTICLES COMPRISING HYPERBRANCHED POLYMER NETWORKS

[00142] In one aspect, disclosed are articles comprising a disclosed hyperbranched polymer network, wherein the article is selected from a polymer film, a thermoset, a polymer coating, an adhesive, and a thermoplastic resin. Thus, in various aspects, the article comprises a hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having a phenyl acetylene end group. In various further aspects, the article comprises a hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having an end group selected from the group consisting of phenyl acetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine, wherein the end group is present in an amount of from about 5 mol% to about 40 mol%.

[00143] In a further aspect, the article is a polymer film.

[00144] In a further aspect, the polymer film has a crosslinking density of from about 0.10 kmol/m³ to about 2.5 kmol/m³. In a still further aspect, the polymer film has a crosslinking density of from about 0.10 kmol/m³ to about 2.0 kmol/m³. In yet a further aspect, the polymer film has a crosslinking density of from about 0.10 kmol/m³ to about 1.5 kmol/m³. In an even further aspect, the polymer film has a crosslinking density of from about 0.10 kmol/m³ to about 1.0 kmol/m³. In a still further aspect, the polymer film has a crosslinking density of from about 0.10 kmol/m³ to about 0.50 kmol/m³. In yet a further aspect, the polymer film has a crosslinking density of from about 0.50 kmol/m³ to about 3.0 kmol/m³. In an even further aspect, the polymer film has a crosslinking density of from about 1.0 kmol/m³ to about 3.0 kmol/m³. In a still further aspect, the polymer film has a crosslinking density of from about 1.5 kmol/m³ to about 3.0 kmol/m³. In yet a further aspect, the polymer film has a crosslinking density of from about 2.0 kmol/m³ to about 3.0 kmol/m³. In an even further aspect, the polymer film has a crosslinking density of from about 2.5 kmol/m³ to about 3.0 kmol/m³. In a still further aspect, the polymer film has a crosslinking density of from about 0.50 kmol/m³ to about 2.5 kmol/m³. In yet a further aspect, the polymer film has a crosslinking density of from about 1.0 kmol/m³ to about 2.0 kmol/m³. In an even further aspect, the polymer film has a crosslinking density of from about 0.20 kmol/m³ to about 2.5 kmol/m³.

[00145] In a further aspect, the polymer film has a maximum tensile strength of from about 35 MPa to about 45 MPa at from about 1.5% to about 2.5% elongation. In a still further aspect, the polymer film has a maximum tensile strength of about 40 MPa at about 2% elongation.

[00146] In a further aspect, the polymer film has a storage modulus of from about 3 GPa to about 4 GPa at a temperature of from about 18 °C to about 25°C.

[00147] In a further aspect, the polymer film has a thickness of from about 125 nm to about 175 nm. In a still further aspect, the polymer film has a thickness of from about 125 nm to about 165 nm. In yet a further aspect, the polymer film has a thickness of from about 125 nm to about 155 nm. In an even further aspect, the polymer film has a thickness of from about 125 nm to about 145 nm. In a still further aspect, the polymer film has a thickness of from about 125 nm to about 135 nm. In yet a further aspect, the polymer film has a thickness of from about 135 nm to about 175 nm. In an even further aspect, the polymer film has a thickness of from about 145 nm to about 175 nm. In a still further aspect, the polymer film has a thickness of from about 155 nm to about 175 nm. In yet a further aspect, the polymer film has a thickness of from about 165 nm to about 175 nm. In an even further aspect, the polymer film has a thickness of from about 135 nm to about 165 nm. In a still further aspect, the polymer film has a thickness of from about 145 nm to about 155 nm.

[00148] In a further aspect, the polymer film has a thickness of about 125 nm. In a still further aspect, the polymer film has a thickness of about 130 nm. In yet a further aspect, the polymer film has a thickness of about 140 nm. In an even further aspect, the polymer film has a thickness of about 150 nm. In a still further aspect, the polymer film has a thickness of about 160 nm. In yet a further aspect, the polymer film has a thickness of about 170 nm. In an even further aspect, the polymer film has a thickness of about 175 nm.

[00149] In a further aspect, the polymer film is prepared via spin-coating.

[00150] In a further aspect, the article is a thermoset.

F. MEMBRANES

[00151] In one aspect, disclosed are membranes having a support and a polymer layer comprising a hyperbranched polymer network, wherein the polymer layer has a thickness of from about 100 nm to about 2 pm, wherein the hyperbranched polymer network comprises a hyperbranched polymer, wherein the hyperbranched polymer comprises a poly(aryletherketone) backbone and at least one residue having an end group, and wherein the hyperbranched polymer is crosslinked via the end group.

[00152] In contrast to linear PAEKs, which are often highly crystalline and intractable, HBPAEKs are readily soluble in common organic solvents at room temperature, and this enables film-casting and spin-coating of all-aromatic PAEK-based membranes. By spin coating the soluble HBPAEK precursor onto a solid support, mechanical properties are less of a concern. In this way the excellent properties and tunability of HBPAEKs can be further explored as membranes.

[00153] Polymeric membranes provide an energy efficient technique to separate valuable gases. Of particular interest is the separation of CO2 from high-pressure gas mixtures containing, e.g., methane to make natural gas and biogas suitable for use as fuels (Baker, R. W. & Lokhandwala, K. Natural Gas Processing with Membranes : An Overview. Ind. Eng. Chem. Res.47, 2109-2121 (2008); Scholz, M., Melin, T. & Wessling, M. Transforming biogas into biomethane using membrane technology. Renew. Sustain. Energy Rev.17, 199- 212 (2013)). To enhance the membrane performance, people often increase the excess free fractional volume (EFFV) in the polymer, or improve the affinity of the polymer towards the permeating component (Sanders, D. F. et al. Energy-efficient polymeric gas separation membranes for a sustainable future : A review. Polymer (Guildf).54, 4729-4761 (2013); Bernardo, P., Drioli, E. & Golemme, G. Membrane Gas Separation : A Review / State of the Art. Ind. Eng. Chem. Res. 4638-4663 (2009)). Well-known polymers for the separation of CO2 from other gasses are the thermally and chemically stable 4,4'- (hexafluoroisopropylidene)diphthalic anhydride (6FDA)-based polyimides. The CF3 groups are believed to restrict torsional motion of the phenyl rings leading to less ordered chain packing and increased excess free volume (Tanaka, K, Okano, M., Toshino, H., Kita, H. & Okamoto, K.-I. Effect of methyl substituents on permeability and permselectivity of gases in polyimides prepared from methyl-substituted phenylenediamines. J. Polym. Sci. Part B Polym. Rhys.30, 907-914 (1992)). Polyimides functionalized with CF3 groups are known to exhibit both higher permeability and permselectivity compared to conventional polyimides due to this additional bulkiness (Matsumoto, K. & Xu, P. Gas permeation of aromatic polyimides. II. Influence of chemical structure. J. Memb. Sci.81, 23-30 (1993); Hirayama, Y. et al. Relation of gas permeability with structure of aromatic polyimides I. J. Memb. Sci. Ill, 169-182 (1996)), while debate continues on the role of the fluorine atoms and their affinity for certain gases (Yampolskii, Y. Polymeric Gas Separation Membranes. Macromolecules 45, 3298-3311 (2012); Raveendran, P. & Wallen, S. L. Exploring C02-philicity: Effects of stepwise fluorination. J. Phys. Chem. B 107, 1473-1477 (2003)). In addition, poly(etherketone)s (PEK) and poly(etheretherketone)s (PEEK) are interesting candidates for their use as high-performance polymer membranes due to their chemical stability and ability to operate at high temperatures (Zheng, Y., Li, S. & Gao, C. Hyperbranched polymers:

advances from. Chem. Soc. Rev. 44, 4091-4130 (2015); Jikei, M. & Kakimoto, M.

Hyperbranched polymers: a promising new class of materials. Prog. Polym. Sci. 26, 1233- 1285 (2001)). However, processing these polymers is hard and requires high temperatures or harsh solvents. They are also semi-crystalline, which is a disadvantage for gas separation membranes as the crystal domains hinder gas transport. For at least these reasons, they have not been previously explored as membranes for gas separation.

[00154] In a further aspect, the polymer layer has a thickness of from about 600 nm to about 800 nm. In a still further aspect, the polymer layer has a thickness of from about 600 nm to about 750 nm. In yet a further aspect, the polymer layer has a thickness of from about 600 nm to about 700 nm. In an even further aspect, the polymer layer has a thickness of from about 600 nm to about 650 nm. In a still further aspect, the polymer layer has a thickness of from about 650 nm to about 800 nm. In yet a further aspect, the polymer layer has a thickness of from about 700 nm to about 800 nm. In an even further aspect, the polymer layer has a thickness of from about 750 nm to about 800 nm. In a still further aspect, the polymer layer has a thickness of from about 650 nm to about 750 nm.

[00155] In a further aspect, the polymer layer has a thickness of about 600 nm. In a still further aspect, the polymer layer has a thickness of about 650 nm. In yet a further aspect, the polymer layer has a thickness of about 700 nm. In an even further aspect, the polymer layer has a thickness of about 750 nm. In a still further aspect, the polymer layer has a thickness of about 800 nm.

[00156] In a further aspect, the poly(aryletherketone) backbone is a polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a polyetherketoneketone (PEKK) backbone.

[00157] In a further aspect, the hyperbranched polymer comprises repeating units having a structure represented by a formula:

wherein each occurrence of R^la and R^lb is selected from the group consisting of halogen and -OAr²; and wherein each occurrence of Ar² is independently selected from the group consisting of 6-membered aryl and 6-membered heteroaryl and is substituted with a phenylacetylene group, provided at least one occurrence of Ar^la and Ar^lb is 6-membered aryl substituted with a phenylacetylene group or 6-membered heteroaryl substituted with a phenylacetylene group, or at least one occurrence of R^la and R^lb is -OAr².

[00158] In a further aspect, the end group is present in an amount of from about 5 mol% to about 40 mol%. In a still further aspect, the end group is present in an amount of from about 5 mol% to about 30 mol%. In yet a further aspect, the end group is present in an amount of from about 5 mol% to about 20 mol%. In an even further aspect, the end group is present in an amount of from about 5 mol% to about 10 mol%. In a still further aspect, the end group is present in an amount of from about 10 mol% to about 40 mol%. In yet a further aspect, the end group is present in an amount of from about 20 mol% to about 40 mol%. In an even further aspect, the end group is present in an amount of from about 30 mol% to about 40 mol%. In a still further aspect, the end group is present in an amount of from about 10 mol% to about 30 mol%. In yet a further aspect, the end group is present in an amount of from about 15 mol% to about 25 mol%.

[00159] In a further aspect, the end group is present in an amount of about 5 mol%. In a still further aspect, the end group is present in an amount of about 10 mol%. In yet a further aspect, the end group is present in an amount of about 15 mol%. In an even further aspect, the end group is present in an amount of about 20 mol%. In a still further aspect, the end group is present in an amount of about 25 mol%. In yet a further aspect, the end group is present in an amount of about 30 mol%. In an even further aspect, the end group is present in an amount of about 35 mol%. In a still further aspect, the end group is present in an amount of about 40 mol%.

[00160] In a further aspect, the end group is selected from phenylacetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine. In a still further aspect, the end group is a phenylacetylene end group.

[00161] In a further aspect, the residue having the phenylacetylene end group has a structure represented by a formula selected from the group consisting of:

[00162] In a further aspect, the residue having the phenylacetylene end group has a structure represented by a formula:

[00163] In a further aspect, the support is an alumina support.

[00164] In a further aspect, the support consists essentially of a top layer and a bottom layer, wherein the top layer is in-between the polymer layer and the bottom layer, wherein the top layer and the bottom layer differ in one or more of thickness, pore size, and porosity. In a still further aspect, the top layer and the bottom layer differ in one or more of thickness and pore size. In yet a further aspect, the top layer and the bottom layer differ in one or more of pore size and porosity. In an even further aspect, the top layer and the bottom layer differ in one or more of thickness and porosity. In a still further aspect, the top layer and the bottom layer differ in thickness. In yet a further aspect, the top layer and the bottom layer differ in pore size. In an even further aspect, the top layer and the bottom layer differ in porosity.

[00165] In a further aspect, the top layer has a thickness of from about 2 pm to about 4 pm, and wherein the bottom layer has a thickness of about 3 mm or less. In a still further aspect, the top layer has a thickness of from about 2 pm to about 3.5 pm, and wherein the bottom layer has a thickness of about 3 mm or less. In yet a further aspect, the top layer has a thickness of from about 2 pm to about 3 pm, and wherein the bottom layer has a thickness of about 3 mm or less. In an even further aspect, the top layer has a thickness of from about 2 pm to about 2.5 pm, and wherein the bottom layer has a thickness of about 3 mm or less. In a still further aspect, the top layer has a thickness of from about 2.5 pm to about 4 pm, and wherein the bottom layer has a thickness of about 3 mm or less. In yet a further aspect, the top layer has a thickness of from about 3 pm to about 4 pm, and wherein the bottom layer has a thickness of about 3 mm or less. In an even further aspect, the top layer has a thickness of from about 3.5 pm to about 4 pm, and wherein the bottom layer has a thickness of about 3 mm or less.

[00166] In a further aspect, the top layer has a thickness of from about 2 pm to about 4 pm, and wherein the bottom layer has a thickness of about 2.5 mm or less. In a still further aspect, the top layer has a thickness of from about 2 pm to about 4 pm, and wherein the bottom layer has a thickness of about 2 mm or less. In yet a further aspect, the top layer has a thickness of from about 2 pm to about 4 pm, and wherein the bottom layer has a thickness of about 1.5 mm or less.

[00167] In a further aspect, the top layer has a thickness of about 3 pm and wherein the bottom layer has a thickness of about 2 mm or less.

[00168] In a further aspect, the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm. In a still further aspect, the top layer has a pore size of from about 2 nm to about 3.5 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm. In yet a further aspect, the top layer has a pore size of from about 2 nm to about 3.0 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm. In an even further aspect, the top layer has a pore size of from about 2 nm to about 2.5 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm. In a still further aspect, the top layer has a pore size of from about 2.5 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm. In yet a further aspect, the top layer has a pore size of from about 3 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm. In a still further aspect, the top layer has a pore size of from about 3.5 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm.

[00169] In a further aspect, the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 110 nm. In a still further aspect, the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 100 nm. In yet a further aspect, the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 90 nm. In an even further aspect, the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 90 nm to about 110 nm. In a still further aspect, the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 100 nm to about 120 nm.

[00170] In a further aspect, the top layer has a pore size of about 3 nm and wherein the bottom layer has a pore size of about 100 nm.

[00171] In a further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 40%. In a still further aspect, the top layer has a porosity of from about 30% to about 45% and wherein the bottom layer has a porosity of from about 20% to about 40%. In yet a further aspect, the top layer has a porosity of from about 30% to about 40% and wherein the bottom layer has a porosity of from about 20% to about 40%. In an even further aspect, the top layer has a porosity of from about 30% to about 35% and wherein the bottom layer has a porosity of from about 20% to about 40%. In a still further aspect, the top layer has a porosity of from about 35% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 40%. In yet a further aspect, the top layer has a porosity of from about 40% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 40%. In an even further aspect, the top layer has a porosity of from about 45% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 40%.

[00172] In a further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 35%. In a still further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 30%. In yet a further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 25%. In an even further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 25% to about 40%. In a still further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 30% to about 40%. In yet a further aspect, the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 35% to about 40%.

[00173] In a further aspect, the top layer has a porosity of about 40% and wherein the bottom layer has a porosity of about 30%. [00174] In a further aspect, the membrane is prepared via solution casting.

[00175] In a further aspect, the membrane is a hollow fiber membrane.

[00176] In a further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 300 °C. In a still further aspect, the membrane has a glass transition temperature (T_g) of from about 180 °C to about 250 °C. In yet a further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 200 °C. In an even further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 300 °C. In a still further aspect, the membrane has a glass transition temperature (T ) of from about 200 °C to about 300 °C. In yet a further aspect, the membrane has a glass transition temperature (T ) of from about 250 °C to about 300 °C. In an even further aspect, the membrane has a glass transition temperature (T ) of from about 200 °C to about 250 °C.

G. METHODS OF MAKING MEMBRANES

[00177] In one aspect, disclosed are methods for making a disclosed membrane. Thus, in various aspects, disclosed are methods for making a disclosed membrane, the method comprising the steps of: (a) providing a composition comprising the hyperbranched polymer network; and (b) coating the composition onto the support; thereby forming the membrane.

[00178] In a further aspect, the membrane is a hollow fiber membrane.

[00179] In a further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 300 °C. In a still further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 250 °C. In yet a further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 200 °C. In an even further aspect, the membrane has a glass transition temperature (T ) of from about 180 °C to about 300 °C. In a still further aspect, the membrane has a glass transition temperature (T ) of from about 200 °C to about 300 °C. In yet a further aspect, the membrane has a glass transition temperature (T ) of from about 250 °C to about 300 °C. In an even further aspect, the membrane has a glass transition temperature (T ) of from about 200 °C to about 250 °C.

H. GAS SEPARATION METHODS USING THE MEMBRANES

[00180] In one aspect, disclosed are methods for separating a first gas species from a second gas species in a gas mixture, wherein the first gas species is different from the second gas species, the method comprising the step of passing the gas mixture through or alongside a disclosed membrane. In a further aspect, the membrane has a support and a polymer layer comprising a hyperbranched polymer network, wherein the polymer layer has a thickness of from about 100 nm to about 2 pm, wherein the hyperbranched polymer network comprises a hyperbranched polymer, wherein the hyperbranched polymer comprises a

[00181] Poly(etheretherketone)s are chemically and thermally very stable and are potentially useful but hardly explored for gas separation purposes. This is due to the semi crystalline nature of the polymer and limited solubility in organic solvents, resulting in a complex processing process and reduced flux. As detailed herein, hyperbranched poly(aryletherketone)s (HBPAEKs) have the desired solubility and have an amorphous nature. Moreover, as exemplified below, HBPAEKs can be spin-coated on a substrate to demonstrate their gas separation properties.

[00182] Polymer dense membranes for gas separation work under the solution-diffusion principle where the size of gas molecules are typically in the range of a few angstrom (A). In a solution-diffusion mechanism the gases are dissolved in the polymer membrane after which they are separated by diffusion. The polymers have no pores but the transport of the gasses take place through the small spaces in between the polymer chains: the excess fractional free volume.

[00183] The permeate is the gas that has passed the membrane and can be collected after. The so-called flux is the amount of gas transported per unit area per unit time. When the flux is corrected for pressure and thickness, it is referred to as the permeability of the membrane. According to the solution-diffusion model, the permeability depends on both the solubility (S) and diffusivity (D) and gives the following equation for gas /:

Pi = S; x D; (1)

A difference in either S or D gives selectivity, a, which is defined as:

[00184] The diffusion in polymer dense membranes is slow and therefore these membranes are often very thin to maintain an acceptable flux. When striving for membranes that have both high selectivity and high permeability, one runs into a dilemma. A more permeable membrane will be less selective, while a more selective membrane will be less permeable. This classical trade-off is to be considered in the design of membranes. Another consideration is that many industrial processes take place at elevated temperatures (> 150 °C), which makes it desirable to separate gases at the processing temperatures used as this will lower the overall energy consumption. Typical polymer membranes show an increase in chain mobility at elevated temperature, compromising their performance. To overcome this temperature restriction, several high temperature polymers were developed, of which poly(benzoxazole)s and poly(benzoxazole-co-imides)s are examples (Jo, H. J. el al.

Thermally Rearranged Poly(benzoxazole- co -imide) Membranes with Superior Mechanical Strength for Gas Separation Obtained by Tuning Chain Rigidity. Macromolecules 48, 2194- 2202 (2015)).

[00185] Another approach is the use of inorganic-organic membranes. Ammonium functionalized polyhedral oligomeric silsesquioxane (POSS) cages can linked together with dianhydrides forming a hyper-cross-linked polyamic acid network that was imidized in an additional thermal treatment step (Raaijmakers, M. J. T., Kappert, E. J., Nijmeijer, A. & Benes, N. E. Thermal Imidization Kinetics of Ultrathin Films of Hybrid Poly(POSS-imide)s. Macromolecules 48, 3031-3039 (2015)). Although ultra-thin homogeneous films could be prepared via interfacial polymerization, the prolonged thermal stability is still low, as the amino groups on the POSS are linked with relatively thermally unstable sp³ carbons.

[00186] Considering PEEK, modified PEEK with a so-called cardo group also increases the solubility, while maintaining the good thermal and mechanical properties (Jansen, J. C., Buonomenna, M. G., Figoli, A. & Drioli, E. Ultra-thin asymmetric gas separation membranes of modified PEEK prepared by the dry-wet phase inversion technique. Desalination 193, 58- 65 (2006)). Increased fluxes for N2 and CH4 were observed, while the ¾ flux remained unchanged. PEEK-WC (with cardo) has a benzolactone group attached that introduces a spiro block into the polymer backbone. The drawback of this approach is that spiro building blocks are often very expensive and therefore not desirable for industrial applications. From the described approaches, branched PEEK, i.e. , HBPAEK, appear to be a desirable way to get a large free volume and use the amorphous nature that is desired for gas separation membranes and keep the excellent thermal and mechanical properties.

[00187] In a further aspect, the poly(aryletherketone) backbone is a polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a polyetherketoneketone (PEKK) backbone. [00188] In a further aspect, the hyperbranched polymer comprises repeating units having a structure represented by a formula:

[00189] In a further aspect, the membrane has a combination of permeability and selectivity that is about equal to or above Robeson's upper limit. In a still further aspect, the membrane has a combination of permeability and selectivity that is about equal to Robeson's upper limit. In yet a further aspect, the membrane has a combination of permeability and selectivity that is above Robeson's upper limit.

[00190] In a further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 2. In a still further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 2.5. In yet a further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 3. In an even further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 3.5. In a still further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 4. In yet a further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 4.5. In an even further aspect, the membrane has a selectivity for the first gas species over the second gas species of at least about 5.

[00191] In a further aspect, the first gas species and the second gas species are

independently selected from the group consisting of CO2, He, ¾, CH4, N2, and O2.

[00192] In a further aspect, the membrane is selective for ¾ over CO2, He, CH4, N2, and/or O2.

[00193] In a further aspect, the membrane is stable at a temperature of about 200 °C or less for fourteen days or less. In a still further aspect, the membrane is stable at a temperature of about 200 °C for at least about fourteen days.

I. EXAMPLES

[00194] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the devices and/or methods claimed herein are made and evaluated, and are intended to be purely exemplary of the invention and are not intended to limit the scope of what the inventors regard as their invention. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in °C or is at ambient temperature, and pressure is at or near atmospheric.

[00195] The Examples are provided herein to illustrate the invention, and should not be construed as limiting the invention in any way. Examples are provided herein to illustrate the invention and should not be construed as limiting the invention in any way.

1. THERMOMECHANICAL PROPERTIES OF CURED PHENYLETHYNYL END- CAPPED HBPAEK REACTIVE PRECURSORS

[00196] Herein, a HBPAEK series in which the phenylethynyl end-group concentration is varied has been disclosed. HBPAEK-69 was used and 10, 20, or 40% of the fluorine (-F) functionalities were replaced with PEP. The samples were labeled HBPAEK-69K-10PEP, HBPAEK-69K-20PEP, and HBPAEK-69K-40PEP, respectively. It was previously demonstrated that neat HBPAEK-69K gives the poorest crosslinking and if the crosslinking for this molecular weight can be promoted with PEP, other molecular weights are envisioned to display a similar effect. The reactive PEP end-group was synthesized via a Sonogashira coupling using 4-iodophenol and phenylethynyl (Yuan, W. Z. et al. Disubstituted

Polyacetylenes Containing Photopolymerizable Vinyl Groups and Polar Ester Functionality: Polymer Synthesis, Aggregation-Enhanced Emission, and Fluorescent Pattern Formation. Macromolecules 40, 3159-3166 (2007)). This specific end-group has an alcohol functionality that allows for the attachment of the phenylethynyl functionality to the polymer backbone in the same fashion as the polymerization of AB2 monomers, namely via a nucleophilic aromatic substitution, as shown in Scheme 1 below. The triple bond will remain dormant until its thermal cure temperature is reached.

SCHEME 1.

HBPAEK-69K HBPAEK-69K-10PEP

HBPAEK-69K-20PEP

HBPAEK-69K-40PEP a. MATERIALS AND EQUIPMENT

[00197] HBPAEK-69K was prepared according to the procedure described above. 4- Iodophenol was purchased from TCI and used as received. Pd(PPh3)2Ch and PPh3 were purchased from Sigma Aldrich and used as received. Phenylethynyl was also purchased from Sigma Aldrich and vacuum distilled before use. Triethylamine was purchased from Alfa Aesar. Dry NMP and dry toluene were obtained from Acros Organics and used as received. A reference PEKK film sample was obtained from Solvay (Ajedium film CYPEK FC).

[00198] Differential Scanning Calorimetry (DSC) curves were measured on a TA instruments 2500 series at 10 °C/min (heating and cooling) under nitrogen atmosphere in crimped aluminium sample pans. Thermal gravimetric analysis (TGA) measurements were performed with a TA instruments 5500 TGA at 10 °C/min under nitrogen purge in aluminium pans. Ή NMR (400 MHz) and ¹³C-NMR (100 Hz) spectra were recorded on a Varian AS- 400 spectrometer and chemical shifts are given in ppm (d) relative to tetramethylsilane (TMS) as an internal standard. The 'H NMR splitting patterns are designated as follows: s (singlet), d (doublet), dd (double doublet), t (triplet), q (quartet), m (multiplet) and b (broad signal). The coupling constants, if given, are reported in Hertz. GPC measurements were performed using a Shimadzu GPU DHU-20A3 equipped with two Shodex LF-804 column and refractive index detector; polystyrene standards were used for calibration of the instrument. All samples were dissolved at a 1 mg/mL concentration in NMP and filtered over a 0.45 pm PTFE filter prior to use. Samples for mass spectrometry were analysed on a Shimadzu GC/MS-QP2010S in electron-impact ionization (El) mode, equipped with an Optic-3 injector and SGE capillary column (PBX5, 30m, 0.25mm). Data were acquired and processed using GCMS solution software. IR spectra were recorded from powdered samples on a Perkin Elmer Spectrum 100 FT-IR Spectrometer, measuring from 600-4000 cm ¹.

[00199] Films were casted in a Petri dish and held under vacuum for lh at r.t, lh at 30 °C, lh at 45 °C, lh at 60 °C, lh at 100 °C, lh at 200 °C, lh at 300 °C, and lh at 350 °C.

Rheology experiments were performed with a Perkin Elmer HAAKE instrument in a parallel plate geometry (8 mm plates) and frequency of 1 Hz with 2% strain. Dynamic mechanical thermal analysis (DTMA) was performed on the HBPAEKs films (approximately 20x3x0.05 mm) at a frequency of 0.1, 1 and 10 Hz at a heating rate of 2 °C/min under nitrogen with a Perkin Elmer Diamond DMTA. Only the storage modulus (E’) and loss modulus (E”) data collected at 1 Hz is reported. The thermal gravimetric analysis (TGA) measurements were done with a Perkin Elmer TGA 4000 at 10 °C/min under nitrogen purge in aluminium pans. Tensile testing was performed on an Instron 3365 at a rate of 0.1 mm/min with thin film samples. Coefficients of thermal expansion (CTE) were measured with a PerkinElmer Diamond Thermal Mechanical Analyser (TMA) between -50 and 50 °C at a heating rate of 5°C/min. b. SYNTHESES OF 4-(PHENYLETHYNYL)PHENOL (PEP)

[00200] The synthetic method reported by Tang et al. was adopted with a slightly modified work-up procedure (Yuan, W. Z. et al. Disubstituted Polyacetylenes Containing

Photopolymerizable Vinyl Groups and Polar Ester Functionality: Polymer Synthesis, Aggregation-Enhanced Emission, and Fluorescent Pattern Formation. Macromolecules 40, 3159-3166 (2007)). To a 1 L 1-neck round-bottom flask was added Pd(PPli₃)Cl₂ (0.8 g, 1 mmol), Cul (0.43 g, 2 mmol) and PPI13 (0.30 g, 1 mmol). The flask was placed under vacuum and subsequently back-filled with Argon. 4-Iodophenol (25 g, 0.11 mmol) in 650 ml Et3N and phenylacetylene (16.35 ml, 0.15 mol) in 150 ml Et3N were added. This was stirred for 24 h before the yellow suspension was filter, washed with Et3N and concentrated. The resulting dark oil was purified via column chromatography over silica in DCM (Rf = 0.2) to give the desired product, 4-(phenylethynyl)phenol (PEP) as a slightly orange product (19 g, 87%). MS (El), m/z: 194 (M). FT-IR (cm ¹): 3400-3000, 2225, 1608, 1590, 1509, 1440, 1371. MP: 125 °C. ¾ NMR (CDCb): d = 7.53-7.51 (d, 2H), 7.44-7.42 (d, 2H), 7.34-7.33 (d, 3H), 6.82-6.80 (d, 2H), 5.2-4.6 (b, 1H). ¹³C NMR (CDCb): 155.57, 133.27, 131.44, 128.31, 127.99, 123.48, 115.67, 115.50, 89.20 (acetylene), 88.09 (acetylene). c. SYNTHESIS OF HBPAEK-69K-20PEP

[00201] To a 100 ml flask was added 2 g of neat HBPAEK-69K (8.54 mmol) and this was dissolved in 30 ml NMP. K2CO3 (0.47 g, 3.4 mmol) and PEP (0.33 g, 1.7 mmol) were added and the solution was stirred at 140 °C for 4 h. The traces of water formed during the reaction are expected to not influence the reaction at this temperature and therefore no Dean-Stark trap was used. The dark solution was precipitated in ice-cold water and neutralized with 1 M HC1. The precipitate was collected, dried in vacuo at 60 °C overnight, dissolved in THF and precipitated in methanol. The pale yellow/white solid was dried in vacuo at 60 °C for 24 h. The yield was quantitative. ¾ NMR (400 MHz, CDCb), d = 7.90-7.50 (m, 2H), 7.30-6.50 (m, 5H). ¹³C NMR (CDCb): 192.88, 162.89, 160.30, 140.72, 132.61, 118.88, 116.48, 112.78, 107.70, 94.47 (acetylene), 89.03 (acetylene). HBP AEK-69K- 10PEP and HBPAEK-69K- 40PEP were prepared in a similar fashion. d. SIZE EXCLUSION CHROMATOGRAPHY

[00202] The HBPAEK-69K precursor end-capped with 10, 20, and 40% end-cap are labelled HBP AEK-69K- 10PEP, HBPAEK-69K-20PEP, and HBPAEK-69K-40PEP and the obtained GPC curves are summarized in FIG. 1 and contrasted with neat HBPAEK-69K start material.

[00203] Referring to FIG. 1 , SEC data of HBPAEK-69K with and without PEP end-cap in NMP at a concentration of 1 mg/ml. With 10% and 20% PEP the MW distribution remains virtually the same. For HBPAEK-69K-40PEP (orange) the MW distribution broadens and shifts towards lower molecular weights.

[00204] Increasing the end-group concentration did not change the MW for the 10 and 20% derivatives, however, when the PEP concentration is increased to 40%, the molecular weight shifts from an Mw of 69K to 20K, as shown in Table . TABLE 1.

[00205] Replacing a large fraction of the electronegative fluorine atoms with non-polar phenyl acetylene functionalities most likely impacts the polymer solubility, /. e.. affect the polymer-solvent interaction, which in turn may account for the observed shift in molecular weight and MW broadening. e. RAMAN SPECTROSCOPY

[00206] Several spectroscopic methods allow for the identification of PEP in our

HBPAEK series. ¹³C NMR has limitations as the acetylene carbon atoms are quaternary and therefore difficult to detect. Visualisation with infrared (IR) spectroscopy is also difficult due to the symmetry of the acetylene triple bond in the PEP end-group. The carbon-carbon symmetric stretch vibration typically results in a very weak signal around 2100 cm ¹. In contrast, Raman spectroscopy is capable of detecting functional groups that have such a symmetric stretch. The Raman spectra of the HBPAEK-69K PEP series are summarized in FIG. 2.

[00207] Referring to FIG. 2, Raman spectra of neat HBPAEK-69K and PEP end-capped HBPAEK-69K series are shown. The signal that corresponds with the carbon-carbon triple bond is visible at 2240 cm ¹ and increases with an increasing concentration of PEP.

[00208] The intensity of the alkyne signal at 2240 cm ¹ increases with an increased concentration of PEP end-cap, while the ketone signal at 1660 cm ¹ remains constant. The resolution is quite poor, which is mainly the result of the background fluorescence caused by the high aromatic content of the polymer. The resolution was unfortunately too poor to allow quantification of the PEP end-groups in the polymer, so we used elemental analysis to further quantify to which extent the fluorine groups on HBPAEK-69K were replaced by PEP. f. NUCLEAR MAGNETIC RESONANCE

[00209] The degree of branching (DB) of a hyperbranched polymer can be determined by nuclear magnetic resonance (NMR) and gives information on the architecture of the polymer. In our case all HBPAEK polymers have a degree of branching of 0.5, which is typical for a randomly branched polymer. NMR can also be used to monitor the number of fluorine end- groups replaced by PEP. ¹⁹F-NMR shows the two different fluorine end-groups in the polymer, belonging to the fluorine atoms on the linear units and terminal units. As they become replaced with the reactive PEP end-group, the intensity of both signals decreases.

This is shown in FIG. 3, where the decrease in NMR signal intensity confirms a decrease in fluorine as the concentration of PEP increases, effectively displacing fluorine in the polymer.

[00210] Referring to FIG. 3, ¹⁹F NMR spectrum of the neat and PEP end-capped

HBPAEK-69K, measured at a concentration of 40 mg/0.6 ml in CDCT is shown. The concentration of fluorine end-groups decreases with increasing amount of PEP end-cap. T = terminal fluorine units, L = linear fluorine units.

[00211] The area under the NMR curve can be calculated by integration and was taken as an absolute area with a straight line mode baseline with Origin Pro 2016 software. The calculated values for both the linear and terminal units are shown below in Table Referring to Table 2, integrated areas under the NMR curve for neat and PEP end-capped HBPAEK- 69K are shown. The area of the terminal (T) units and linear (L) units of the HBPAEK-69K is set as 100%, combined they are set as 100% for the total decrease in area in the 4^th column. The decrease is compared with reduction of fluorine from elemental analysis (EA).

TABLE 2.

[00212] From Table that the total decrease in area for all PEP end-capped HBPAEK does not correspond with the intended amount of PEP that was desired to be replaced. Without wishing to be bound by theory, a possible explanation for this could be that -F groups are replaced for -OH groups during the addition of the PEP end-group, as water is formed during the conversion of the PEP end-group to its corresponding potassium salt. g. ELEMENTAL ANALYSIS

[00213] With NMR measurements a trend in decreasing fluorine content was clearly observed, which could also be confirmed with elemental analysis, where the fluorine content is directly measured by combustion ion chromatography and the results are listed in Table 3. The measured content of fluorine for the neat polymer is lower than calculated by Chemdraw 15 software, where the most probable explanation was found to be hydrolysis of some of the fluorine groups. For the PEP end-capped HBPAEKs a clear trend in reduction of the fluorine content of the PEP functionalized polymer is seen. This is additional proof that the fluorine groups can be replaced by the reactive PEP end-groups in a controlled way. The percentage decrease in fluorine content is shown in Table 3 and compared to the reduced area under the curve from the NMR spectra. Both methods show that more fluorine is replaced than intended and this is probably related to additional dehalogenation during synthesis. Elemental analysis is very sensitive, requires a less sensitive sample preparation and errors in the integration of the NMR curves are avoided. That makes it less prone to error and is thus more reliable.

TABLE 3.

a Calculated using Chemdraw 15 software; ^b Measured by elemental analysis; ^c Uncured from DSC, 20 °C/min under nitrogen; ^d Determined by DTMA, as max in G”; ^e From initial slope tensile test, at r.t; ^f M_e=pRT/G’, with p=1.3 kg/m³ at 623K.

h. GLASS TRANSITION TEMPERATURE

[00214] The glass transition temperatures (T ) of the PEP -functionalized HBPAEK series were measured with differential scanning calorimetry (DSC). The DSC scans of the first heat are shown in Referring to FIG. 4, and the results are summarized in Table 3. [00215] Referring to FIG. 4, first heat of the DSC curves of HBPAEK-69 and PEP end- capped HBPAEK-69K, measured with a heating rate of 20 °C/min under nitrogen, are shown. The effect of PEP end-group on the T is most apparent for HBPAEK-69K-40PEP.

[00216] All polymers remain amorphous, there is no indication that (high concentrations of) PEP induces crystallization. Introducing PEP does not seem to have a major effect on the T_g. The T_g of HBPAEK-69K is 151 °C and introducing 10% PEP or 20% PEP increases the T_g to 152 and 154 °C, respectively. The exception is HBPAEK-69-40PEP where the T_g drops by ~20 °C to 132 °C. This is the result of a dramatic change in polarity going from a

HBPAEK with a high content of electronegative fluorine atoms at the periphery to a

HBPAEK with a high content of non-polar phenylacetylene functionalities. This is in line with earlier reported T_g changes for HBPAEKs. Hawker et al. showed that replacing the polar -F end-group for the less polar benzophenone end-group results in a T_g drop from 162 °C to 117 °C. i. RHEOLOGICAL BEHAVIOUR AND CROSSLINKING

[00217] The viscoelastic behaviour of neat HBPAEK-69K and the PEP end-capped HBPAEKs were evaluated using parallel-plate rheology and the results are summarized in Referring to FIG. 5,. Whereas HBPAEK-69K shows a gradual decrease in storage modulus (G’) over the whole temperature range up to 350 °C, the PEP terminated analogs show a minimum in G’ at around 250 °C. More specifically, HBPAEK-69- 10PEP and HBPAEK-69- 20PEP show a minimal G’ value of 500 Pa and HBPAEK-69-40PEP shows a G’ as low as 10 Pa. The crosslinking event for the PEP end-capped HBPAEK-69K series starts around 250 °C, which is evident by a rapid increase in G‘. This is much earlier than the reported crosslink temperature of the phenylethynyl bond in literature, which is around 300 °C (Roberts, C. C., Apple, T. M. & Wnek, G. E. Curing chemistry of phenylethynyl-terminated imide oligomers: Synthesis ofl3C-labeled oligomers and solid-state NMR studies. J. Polym. Sci. Part A Polym. Chem. 38, 3486-3497 (2000)). Neat HBPAEK-69K lacks PEP reactive end-groups and shows a slow increase of G’ during the 350 °C lh. hold, which is the result of thermal induced post condensation chemistry. Crosslinking of the PEP terminated HBPAEKs is almost complete when the hold temperature of 350 °C is reached. The moderate increase in G’ during the lh. hold can be attributed to additional crosslinking of the PEP functionalities and/or crosslinking via any remaining free -OH and -F functionalities. For all PEP terminated HBPAEKs a similar rubber plateau level of 500 KPa is obtained after a lh. hold at 350 °C. The reference polymer, HBPAEK-69K, does not reach a plateau and in fact G’ is still increasing after the 1 h. hold.

[00218] Referring to FIG. 5, rheology curves of HBPAEK-69K and HBPAEK-69K with 10, 20 and 40% PEP are shown; 8 mm pellets under nitrogen, 5 °C/min ramp to 350 °C followed by an isothermal hold of lh. at 350 °C.

[00219] The molecular weight of entanglement (M_e) can be calculated from the G’ plateau value at 350 °C after a 25 min hold and is calculated to be in the range of 11-18K for HBPAEKS with PEP and 373K for the neat HBPAEK-69K without PEP, as shown in Table 3. This means the crosslinking density is much higher for the HBPAEKs with PEP. The crosslinking density u can be calculated by using the following equation (Jiang, H., Su, W., Mather, P. T. & Bunning, T. J. Rheology of highly swollen chitosan/poly acrylate hydrogels ): u = G7RT (1) where G’ is the shear storage modulus at 350 °C (623 K) and R is the universal gas constant (8.3 m³ Pa/Kmol). The calculated values are displayed in Table 4.

TABLE 4.

with p=1.3 kg/m³ at 623K.

[00220] The crosslink density from the neat HBPAEK-69k (Table 4, entry 1) is the result of the coupling of -F and -OH and is at least a factor 50 lower than the PEP end-capped HBPAEK-69Ks. From the rheology experiments it was concluded that the HBPAEK-69K can cure by its existing end-groups but the process is slow and the crosslink density is much lower. Adding reactive PEP end-groups speeds up the crosslinking reaction and additionally gives a higher crosslinking density. j. THERMAL GRAVIMETRIC ANALYSIS

[00221] The thermal gravimetric analysis of the cured HBPAEKs showed a <2% weight loss at 450 °C with a char yield of >90% at 550 °C. The plots are shown in FIG. 6.

[00222] Referring to FIG. 6, thermogravimetric analysis results for HBPAEK-69K and HBPAEK-69K with 10, 20, and 40% PEP cured at 350 °C for 1 h are shown. Included is LPEEK for reference purposes; nitrogen atmosphere and a heating rate of 10 °C/min.

[00223] The cured neat and PEP end-capped HBPAEK-69K show a higher weight loss than the linear PEEK reference and the HBPAEK-69 start material, probably the result of outgassing of smaller weight fractions that were trapped within the polymer branches. All the weight loss values are listed in Table 5.

TABLE 5.

a T_d2% is reported at the 2% weight loss under N2 using a heating rate of 10 °C/min b T_d5% is reported at the 5% weight loss under N2 using a heating rate of 10 °C/min k. FILM CASTING

[00224] The HBPAEKs films were casted from a 10 wt./wt.% solution in NMP onto glass petri dishes with a diameter of 6 cm. Light brown coloured transparent films were obtained by applying a stepwise temperature program under vacuum. Without wishing to be bound by theory, it was found that the HBPAEK films adhere strongly to the glass substrate, which often resulted in cracked films upon cooling due to the large difference in coefficient of thermal expansion (CTE). The CTE of the cured HBPAEK with PEP films is about 20* 10 ⁶ °C '. which is about 5 times higher than the CTE of the Petri Dish (Pyrex glass). The CTE of the crosslinked HBPAEK with PEP is slightly lower than that of linear PEKK (Solvay) reference sample, which is reported as 25.5* 10 ^{6 0}C '. Applying mould release agent significantly reduced the adhesion of the HBPAEKs to the glass substrate and the films with PEP reactive end-groups could easily be removed after the temperature treatment. The HBPAEK-69K without PEP end-groups remained too brittle for any mechanical testing. The HBPAEKs are more effectively crosslinked with PEP, compared to a post-condensation process. HBPAEK-based films, with and without PEP end-groups, are shown FIG. 7.

[00225] Referring to FIG. 7, pictures of cast HBPAEK-69K films after curing at 350 °C are shown. HBPAEK-69K, cast on a glass Petri dish (6 cm diameter), already cracks upon cooling in the oven after thermal curing (square (A)). Free-standing films cannot be obtained from the HBPAEK-69K film as the material is too brittle (square (B)). HBPAEK-69K with PEP (40% PEP shown here) does give a homogeneous transparent film without cracks (square (C)). A free standing flexible film could be removed from the glass and exhibits excellent handleability/flexibility (square (D)). The films are 50 +/- 1 pm thick.

[00226] As expected, the cured HBPAEK films are too brittle and do not result in free standing films. The lack of chain entanglements and low crosslink density result in films that cannot carry any mechanical load. The contrast with PEP end-capped HBPAEK is significant, as the increased crosslink density results in films that can even be bend 180° without breaking.

1. SOL/GEL FRACTION

[00227] The sol/gel fraction of the neat and end-capped-HBPAEK-69K polymers films, after being cured at 350 °C, was determined by soaking pieces of film (lxl cm) for 24 h. at room temperature in chloroform, which is a good solvent for the polymer. Neat HBPAEK- 69K gives a significant lower gel fraction than the PEP end-capped HBPAEKs, which show gel fractions of up to 98%, as shown in Table 6.

[00228] Referring to Table 6, sol/gel fraction of neat and PEP end-capped HBPAEK-69K are detailed. Chloroform was used as solvent to soak a piece of film (lxl cm) for 24 h, after which the film was collected, dried in a vacuum oven for 3 days at 60 ^°C and weighed.

TABLE 6.

[00229] Without wishing to be bound by theory, this supports the hypothesis that the neat HBPAEK-69K polymer globules are not well-connected and slightly crosslinked only. This may explain why soluble fractions could be removed from this polymer. In other words, introducing PEP in this series HBPAEKs is an effective method towards improving the crosslink density and hence the film mechanical properties. m. MECHANICAL TESTING

[00230] Dynamic mechanical thermal analysis. The flexible and transparent cured HBPAEK films were tested using a DMT A, which allowed for the glass transition and thermal behaviour to be monitored over a temperature range, and the results are shown in FIG. 8A and FIG. 8B. The initial storage modulus is in the 3-4 GPa range, which is in line with reported values for all-aromatic high-performance polymers and is also in the same range as the reference sample (linear PEKK, Solvay). The glass transition is marked by a sudden drop in E’, typically observed for amorphous polymers. The films are robust and do not break over the whole temperature range with an increase in E’ from 325 °C due to post curing of unreacted phenylethynyl groups and/or cure via remaining -F/-OH groups. The rubbery plateau of the PEP end-capped HBPAEKs is increased with the amount of crosslinker.

[00231] Referring to FIG. 8A, DMTA curves of partially PEP end-capped HBPAEKs, under nitrogen, 2 °C per min, 1 Hz, are shown. The PEKK reference measurements terminates at 175 °C (above T_g), as the film softens and elongates too much. An increase in G’ after 300 °C is observed for all HBPAEK samples.

[00232] Referring to FIG. 8B, G” from DMTA for end-capped HBPAEKs, the T_g is measured as maximum of G”.

[00233] The T_g’s of the HBPAEKs are much higher than that of linear PEKK. PEKK became too soft and stretched too much so the measurement terminated at 180 °C. The T_g’s of the HBPAEKs are visible around 200 °C and all films remain intact over the whole temperature range as a result of network formation.

[00234] The crosslinking density u can be calculated by using the following equation: u = E73RT (2) where E’ is the storage modulus of the cured film at 350 °C (623 K) and R is the universal gas constant (8.3 m³ Pa/Kmol).¹⁴ The calculated values are displayed in Table . TABLE 7.

calculated using Eq. (2); ^c From DMT A, M_e=pRT/(E73), with p=1.3 kg/m³; ^d From rheology, as the films are too brittle for mechanical testing.

[00235] The storage modulus at 350 °C increases with the percentage of PEP added to the HBPAEK-69K and this also results in an increased crosslinking density. The crosslink densities that are calculated from the DMTA results are higher than from the rheology results displayed in Table 4. This is probably the effect of the cure temperature program, as the HBPAEK films for DMTA were solution-casted and cured stepwise in a vacuum oven and were exposed to a higher temperature for a longer period of time in between the temperature stages.

[00236] The HBPAEKs curves in FIG. 8A and FIG. 8B show an increase in G’ after the rubbery plateau, between 225-325 °C, indicating a post-curing event. To further explore this, a HBPAEK-69K-20PEP film was measured three times in a row and the results are displayed in FIG. 9 A and FIG. 9B.

[00237] Referring to FIG. 9A, storage modulus against temperature of three consecutive runs on 1 sample of HBPAEK-69K-20PEP is shown; N2 atmosphere, 2 °C per min, 1 Hz. Referring to FIG. 9B, loss modulus of the corresponding curves in FIG. 9A is shown.

[00238] The T_g for the HBPAEK-69K-20PEP in FIG. 9A and FIG. 9B shifts from 187 to 252 °C and the rubbery plateau increases an order of magnitude from 3 MPa to 22 MPa to even 40 MPa (at 350 °C). This indicates that the post-curing results in a network with a higher crosslink density, as also calculated and shown in entries 2, 3 and 4 in Table . An increase in crosslink density directly relates to a lower M_e value, which is confirmed and also shown in Table . The samples showed increased brittleness after being exposed repeatedly to the thermal cure program.

[00239] Tensile testing. In order for HBPs to form networks that carry mechanical loads, the individual polymer globules need to be connected, hereby also taking the packing efficiency in mind and the chance of end-groups finding each other to connect. FIG. 10A-D summarizes the stress-strain results of the PEP end-capped HBPAEK-69K series, including a commercial PEKK reference sample. The elastic modulus can be calculated from the initial slope and adopts a value of ~2-4 GPa, as also displayed in Referring to Table 8.

[00240] Referring to FIG. 10A-D, Tensile data on PEP end-capped HBPAEK-69Ks, measured against linear PEKK (Solvay) as a reference with a strain rate of 0.1 mm/min are shown. Specifically, stress/strain behaviour of the PEP end-capped HBPAEK-69Ks and the PEKK reference are shown in FIG. 10A. All HBPAEK films were cured at 350 °C for 1 h. Elongation at break is shown in FIG. 10B, elastic modulus is shown in FIG. IOC, and maximum tensile stress is shown in FIG. 10D. The error bars shown represent the upper and lower values obtained from 3 film samples.

[00241] The HBPAEK have a higher initial storage modulus, compared to the linear PEKK. The maximum tensile stress, maximum tensile strain and toughness are lower, due to the large difference in polymer backbone architecture.

[00242] Referring to Table 8, tensile data of cured HBPAEK films is shown. Solvay PEKK is included for reference purposes. Applied strain rate is 0.1 mm/min.

TABLE 8.

a obtained from initial slope; ^b measured up to 5% elongation; ^c sample did not break

[00243] The toughness of these HBPAEKs can be calculated from the stress-strain curve in FIG. 11A by integrating the area under the curve and a value of -0.3 kJ/m³ was obtained, which is in the range of typical epoxide thermosets (Cambridge University Engineering Department. Materials data sources. Mater. Des. 9, 305 (1988)). In terms of stress-strain behaviour, the HBPAEKs also behave like typical epoxide thermosets that also have a relatively low elongation at break (<5%) (Goodman, S. H. Handbook of thermoset plastics. (Elsevier Science, 1998)). The concentration of PEP does not result in a significant change in mechanical properties. A concentration of 10% PEP is already enough to effectively crosslink the HBPAEK-69K and any additional connections that are made via the crosslinks do not contribute to the overall strength. [00244] The crosslinked HBPAEK films show brittle fracture and different behaviour than the linear PEKK sample. In the linear PEKK sample, plastic deformation is shown after 2% elongation, while no plastic deformation is visible with HBPAEKs. The fact that HBPAEKs only show elastic deformation probably comes directly from the difference in architecture, as the HBPAEK do not have chain entanglements and have a lot of branches. This is schematically represented in FIG. 11 A and FIG. 1 IB.

[00245] Referring to FIG. 11 A, a schematic representation of the elongation of a linear polymer is shown. Linear polymer chains tend to align in the direction of the applied stress field when stretched and slowly start to disentangle.

[00246] Referring to FIG. 1 IB, a schematic representation of the elongation of a crosslinked hyperbranched polymer is shown. Crosslinked hyperbranched polymers hardly elongate, as the chains are fixed and have limited mobility.

[00247] Typically, linear amorphous polymers go through several phases when being stretched (Ward, I. M. & Sweeney, J. Mechanical properties of solid polymers. John Wiley & Sons (1983)). Firstly, there is elastic deformation where the polymer is able to recover its shape after the stress is released. Secondly, the polymer reaches its yield point after which it enters a plastic deformation region and no recovery to its original shape is possible anymore. This yield point often involves a slight drop in stress due to the formation of a so-called neck. Thirdly, upon further stretching the polymer chains start to disentangle, followed by a drawing region where the tensile strength increases dramatically due to alignment of the chains. Lastly, the polymer fractures.

[00248] Crystallinity, crosslinking or branching can influence the tensile behaviour, as the polymer network will be limited in its movement. When a semi-crystalline polymer is stretched, the drawing region is limited and no dramatic gain in tensile stress is observed. Semi-crystalline polymers such as polyethylene typically display necking behaviour and a yield point in tensile stress-strain curves. Yield points are associated with a deformation mechanism which absorbs energy. For semi-crystalline polymers the mechanism involves orientation and destruction of micron to colloidal scale semi-crystalline morphologies.

[00249] When a polymer is crosslinked, the polymer chains cannot stretch as easily as they are fixed, resulting in a very different stress-strain behaviour, where brittle fracture occurs even before the yield point. A un-crosslinked hyperbranched polymer does not have chain entanglements and thus cannot elongate, which often makes them too brittle to even confirm this behaviour on a tensile tester. In contrast, a crosslinked hyperbranched polymer shows structural similarities with a crosslinked epoxide polymer network and therefore similar tensile behaviour is expected. This is also what we observed from the obtained stress-strain curves. Competing mechanical properties is not the only benefit of these solution- processable and thermally stable PEP end-capped HBPAEKs, as they could serve as membranes for gas separation at high temperatures.

[00250] In sum, it has been demonstrated that reactive PEP end-groups (10, 20, and 40%) can be added to hyperbranched poly(aryl ether ketone)s (HBPAEKs) to get access to solution-processable polymers that give flexible and transparent films that were mechanically tested. The T_g was increased from 151 to 187 °C after curing, and even to 252 °C with additional curing time and increased temperature. Rheology experiments revealed a rapid increase in storage modulus between 250-350 °C, confirming that the PEP end-groups are effective crosslinking functionalities. The M_e was calculated for the neat and PEP end-capped HBPAEK-69K, with values of 11 -18 kg/mol for the PEP end-capped HBPAEK, compared to 1100 kg/mol for the neat HBPAEK-69K. An increased concentration of PEP resulted in an increase in crosslink density and a corresponding decrease in M_e.

[00251] All PEP end-capped HBPAEK-69K were capable of forming free-standing films that could be mechanically tested; a direct result of the increased crosslink density.

Crosslinked films exhibited a maximum tensile strength of ~40 MPa at 2% elongation, which translates to a toughness of -0.3 kJ/m³. The obtained storage modulus from DMA on the HBPAEKs films at r.t. is 3-4 GPa and outperforms the reference linear PEKK (2.5 GPa).

[00252] Without wishing to be bound by theory, the results show that a reactive hyperbranched polymer precursor approach results in an easy processable polymer with low viscosity that can be cured to give competing properties compared to regular thermosetting, i.e., epoxide, polymer systems.

2. CROSSLINKED HBPAEK MEMBRANES FOR GAS SEPARATION

APPLICATIONS

[00253] While polymers like linear PEK or PEEK are often insoluble, HBPAEKs are soluble at room temperature in solvents such as THF, CHCb and NMP (Morikawa, A.

Comparison of Properties among Dendritic and Hyperbranched Poly(ether ether ketone)s and Linear Poly(ether ketone)s. Molecules 21, (2016)), which offer significant advantages in terms of solution-based thin film processing, as shown in FIG. 12. These thin films can be used as membranes for the gas separation of, for example, ¾ and CO2. A benefit of the HBPAEKs is their amorphous nature due to their high degree of branching (DB=0.5).

Additionally, branching increases the excess free volume (EFFY) of the polymer network, which is an important parameter for a membrane (Lederer, A. & Burchard, W.

Hyperbranched Polymers . (The Royal Society of Chemistry, 2015).

doi: 10.1039/9781782622468). To improve the mechanical properties of the HBPAEK and to increase the EFFV and T of the final membranes, the following possibilities were explored: (1) crosslinking the polymers via self-condensation; and (2) crosslinking the polymers by adding reactive end-groups in the form of phenylacetylene (Mu, J., Zhang, C., Wu, W., Chen, J. & Jiang, Z. Synthesis, Characterization, and Functionalization of Hyperbranched

Poly(ether ether ketone)s with Phenoxyphenyl Side Group.

doi: 10.1080/10601320802222707). Without wishing to be bound by theory, the resulting rigid polymer network is also envisioned to provide resistance against plasticization by CO2, a frequently occurring phenomenon for membranes where the gas separation capabilities are significantly reduced or even lost due to increased mobility of the polymer chains. a. MATERIALS AND EQUIPMENT

[00254] Dry NMP was obtained from Acros Organics and used as received. Phenyl acetylene was purchased from Sigma Aldrich and vacuum distilled before use. Glass transition temperatures of the HBPAEKs before cure were measured at mid-point with differential scanning calorimetry (DSC) using a TA instruments 2500 series with a rate of 10 °C/min under nitrogen atmosphere. The thermal gravimetric analysis (TGA) measurements were done with a TA instruments 5500 TGA at 10 °C/min under nitrogen purge in aluminium pans.

[00255] Ή NMR (400 MHz) and ¹³C NMR (100 Hz) spectra were recorded on a Varian AS-400 spectrometer and chemical shifts are given in ppm (d) relative to tetramethyl silane (TMS) as an internal standard. The 'H NMR splitting patterns are designated as follows: s (singlet), d (doublet), dd (double doublet), t (triplet), q (quartet), m (multiplet) and b (broad signal). The coupling constants, if given, are in Hertz.

[00256] Size exclusion chromatography (SEC) spectra were obtained using Waters 2695 separations module liquid chromatograph, Waters 2414 refractive index detector at room temperature, and Waters 2996 photodiode array detector with styragel HR columns.

Tetrahydrofuran was the mobile phase and the flow rate was set to 1 mL/min. The instrument was calibrated using polystyrene standards in the range of 580 to 892,800 Da. All samples were dissolved at a 1 mg/mL concentration in THF and filtered over a 0.45 pm PTFE filter prior to use. [00257] The density of HBPAEKs was measured using an AccuPyc II 1340 gas displacement density analyser (Micrometries, USA), using helium as gas source. For each sample, 150 individual density measurements were performed, where only the last 50 measurements were used to obtain the average density. b. SYNTHESES

[00258] Three batches of similar MW fluorine-terminated HBPAEKs were synthesized as detailed above: HBPAEK-33K, HBPAEK-28K, and HBPAEK-25K. The differences in MW come from slight deviations in reaction time and are not expected to be of influence for this study. From these 3 batches, HBPAEK-28K was end-capped with 10% PEP and HBPAEK- 25K was end-capped with 20% PEP. The PEP end-capped HBPAEKs were synthesized via the method described in this section.

[00259] HBPAEK-28K-10PEP. To a 100 ml flask was added 2 g of 28K HBPAEK and this was dissolved in 30 ml NMP. K2CO3 (0.24 g, 1.7 mmol) and PEP (0.17 g, 0.85 mmol) were added and the solution stirred at 160 °C overnight. The dark solution was precipitated in ice-cold water and the solid was collected, washed in a Soxhlet apparatus for 24 h with MeOH and dried in vacuo at 60 °C. The yield was quantitative. 'H NMR (400 MHz, CDCh), 5 = 7.88-7.51 (m, 2H), 7.31-6.50 (m, 5H). ¹³C NMR (CDCh): 192.80, 162.90, 160.32,

140.69, 132.61, 118.91, 116.51, 112.78, 107.70, 94.49 (alkyne), 89.05 (alkyne).

[00260] HBPAEK-25K-20PEP. To a 100 ml flask was added 2 g of 25K HBPAEK and this was dissolved in 30 ml NMP. K2CO3 (0.47 g, 3.4 mmol)) and PEP (0.33 g, 1.7 mmol) were added and the solution stirred at 160 °C overnight. The dark solution was precipitated in ice-cold water and the solid was collected, washed in a Soxhlet apparatus for 24 h with MeOH and dried in vacuo at 60 °C. The yield was quantitative. 'H NMR (400 MHz, CDCh), 5 = 7.90-7.50 (m, 2H), 7.30-6.50 (m, 5H). ¹³C NMR (CDCh): 192.88, 162.89, 160.30,

140.72, 132.61, 118.88, 116.48, 112.78, 107.70, 94.47 (alkyne), 89.03 (alkyne). c. ELLIPSOMETRY

[00261] Film preparation. Thin HBPAEKs films with a thickness of -150 nm were spin- coated (Laurell WS-400B-6NPP-Lite) on a silicon wafer (100, front side polished, CZ test grade, Silchem). Depending on the wafer size, 40-120 pL of HBPAEK (1.5 wt% in CHCh or 3 wt% in cyclopentanone) was deposited with a spin-coating speed of 4000 rpm for 30 seconds. Films were annealed for 30 minutes at 200 °C under nitrogen atmosphere. [00262] T measurements by in-situ spectroscopic elliysometry. The thickness and refractive index of HBPAEKs films on silicon wafers were measured as function of time and temperature by in-situ spectroscopic ellipsometry (SE). Measurements were performed on a M2000-XI ellipsometer (J.A. Woolam Co., USA) equipped with a heat stage (THMSEL600, Linkam, UK), calibrated as described elsewhere (Kappert, E. J. et al. Temperature calibration procedure for thin film substrates for thermo-ellipsometric analysis using melting point standards. Thermochim. Acta 601, 29-32 (2015)). Measurements were conducted at a fixed angle of 70°, in the full wavelength range of 210-1000 nm under a 100 mL/min dry nitrogen flow. The initial T_g before thermal treatment was measured by heating the samples to 200 °C with 5 °C /min, where the samples were held for 15 min and sequentially cooled down again with 5 °C /min. The T_g was determined according to a literature reported procedure

(Ogieglo, W., Wormeester, EL, Wessling, M. & Benes, N. E. Effective medium

approximations for penetrant sorption in glassy polymers accounting for excess free volume. Polymer (Guildj). 55, 1737-1744 (2014)).

[00263] Thermal cure programs. The two different temperature programs that were used to crosslink the HBPAEKs are shown in FIG. 13A and FIG. 13B. Program“lh@280 °C” has a heating and cooling rate of 5 °C /min, and a lh dwell temperature of 280 °C to target only the post-condensation process of the HBPAEKs. Program“lh@280°C+lh@350°C” has a heating and cooling rate of 5 °C /min and a dwell of lh at 280 and lh 350 °C to target both the post-condensation and the phenylacetylene crosslinking. At least two different samples were measured for each temperature program.

[00264] Referring to FIG. 13A and FIG. 13B, the thermal crosslink profile used for this study as a function of temperature versus time is shown. Specifically, the temperature profile with an isothermal hold at 280 °C for lh is shown in FIG. 13A and the temperature profile with a isothermal hold at 280 °C for lh and 350 °C for lh is shown in FIG. 13B. MAAK ER 1H280 en 3501H.

[00265] The obtained spectra were analysed using CompleteEASE (v4.86, J.A. Woollam Co., USA). The HBPAEK film was modelled as an isotropic Cauchy layer fitted in the wavelength range from 500-1000 nm (fit parameters: thickness, A, B, and k, the Urbach absorption tail), on top of a Silicon wafer with a 2 nm native oxide layer. The temperature dependent optical parameters of the silicon wafer are taken from the literature (Herzinger, C. M., Johs, B., McGahan, W. A., Woollam, J. A. & Paulson, W. Ellipsometric determination of optical constants for silicon and thermally grown silicon dioxide via a multi-sample, multi wavelength, multi-angle investigation. J. Appl. Phys. 83, 3323-3336 (1998)). [00266] ( '() sorption by in-situ spectroscopic elliysometry. CO2 sorption experiments were conducted at elevated gas pressures with an Alpha-SE ellipsometer® (J.A. Woollam Co. Inc.). All measurements were performed at a fixed angle of 70° and a wavelength range of 370-900 nm. A home-built cell stainless steel cell (Pmax=200 bar, Tmax=200 °C) equipped with a temperature and pressure control system was used. The pressure was controlled and stabilized using a syringe pump (Teledyne ISCO, 500D), and the temperature of the pump was kept constant using a water bath at 35 °C. A correction for pressure-induced

birefringence of the cell windows was performed using a high-pressure CO2 calibration measurement on a 500 nm SiCh/Si wafer.

[00267] The obtained spectra were modelled using CompleteEASE (v4.86, J.A. Woollam Co., USA). The HBPAEK film was modelled as an isotropic Cauchy layer fitted in the wavelength range from 500-900 nm (fit parameters: thickness, A, B, and k, the Urbach absorption tail). The ambient was fitted as a Cauchy dispersion with the pressure dependent refractive index of CO2 (Obriot, J., Ge, J., Bose, T. K. & St-Amaud, J.-M. Determination of the density from simultaneous measurements of the refractive index and the dielectric constant of gaseous CH4, SF6, and C02. Fluid Phase Equilib. 86, 314-350 (1993))_. From the film thickness and the refractive index the concentration of sorbed CO2 can be calculated using the Clausius-Mosotti equation (Horn, N. R. & Paul, D. R. Carbon Dioxide Sorption and Plasticization of Thin Glassy Polymer Films Tracked by Optical Methods. Macromolecules 45, 2820-2834 (2012); Simons, K. et al. C02 sorption and transport behavior of ODPA- based polyetherimide polymer films. Polymer (Guildf). 51, 3907-3917 (2010)). d. MEMBRANE PREPARATION AND CHARACTERIZATION

[00268] HBPAEK membranes for gas separation experiments were prepared by dynamically spin-coating the polymer on an a-alumina porous support with a 3 pm thick g- alumina top-layer (Pervatech, the Netherlands). HBPAEKs were dissolved in c-pentanone (3 wt%) overnight. 0.15 mL of polymer solution was spun for 10 seconds at 500 rpm, followed by 5 minutes at 1000 rpm. The membranes were annealed directly after their synthesis to remove anisotropy induced by spin-coating. All membranes were heated to 200 °C with a heating rate of 10 °C/min for 30 minutes in a chamber furnace under a nitrogen atmosphere (Carbolite HTMA 5/28 500 °C). The membranes were cured by using the cross-link programs described in the previous section. The membrane thickness, used to calculate permeability, was assumed to be constant for all membranes, due to the identical spin-coating conditions. e. CONTACT ANGLE MEASUREMENTS

[00269] Static contact angle measurements on spin-coated HBPAEK films on silicon wafers were performed by the sessile drop method (2 pL, Mili-Q water) with an OCA 15 (Dataphysics, Germany). The contact angle was determined 3s after applying the water droplet to the surface with Python (v3.5) software using the scipy.ndimage package (vO.18.1). f. H₂O SORPTION BY IN SITU SPECTROSCOPIC ELLIPSOMETRY

[00270] SE measurements with varying humidity were performed on a M2000-X (J.A. Woollam Co., USA) ellipsometer equipped with a heated liquid cell (J.A. Woollam Co., USA) at a fixed angle of 75°. The temperature of the liquid cell was set to 35 °C. Nitrogen gas was bubbled through two bubblers in series filled with water, and mixed with dry nitrogen. The sum of the two flows was kept constant at 300 mL/min. A humidity sensor (Sensirion digital humidity sensor, SHTW2) was placed at the outlet of the cell, and the humidity in the cell was calculated from the humidity and temperature measured at the outlet of the cell by using the Buck equation (Buck, A. L. New Equations for Computing Vapor Pressure and Enhancement Factor. J. Appl. Meteorol. 20, 1527-1532 (1981)). The maximum humidity for this set-up was 50%. g. SIZE EXCLUSION CHROMATOGRAPHY

[00271] The molecular weight of the investigated HBPAEKs are all in the same range to exclude possible effects of molecular weight on the polymers properties. The SEC curves are shown in FIG. 14.

[00272] Referring to FIG. 14, SEC data of HBPAEK-33K, HBPAEK-28K- 10-PEP, and HBPAEK-25K-20PEP in THF at a concentration of 1 mg/ml are shown. All samples show a broad distribution and low MW fractions are visible towards the tail of the curves at a retention time close to 40 min.

[00273] The obtained M_n, M_w and polydispersity (PDI) from the SEC curves are listed in Table 9. There is no effect of adding the 10 and 20% PEP on the molecular weight. The PDI values of all polymers are relatively high, characteristic for randomly branched

hyperbranched polymers. The degree of branching for all HBPAEKs was around the theoretical value of 0.5 and was determined as previously described (Hawker, C. J. & Chu, F. Hyperbranched Poly(ether ketones): Manipulation of Structure and Physical Properties. Macromolecules 29, 4370-4380 (1996)). TABLE 9.

Obtained with size exclusion chromatography in THF (1 mg/ml); ^b Obtained with DSC as mid-point value, 20 °C/min under nitrogen; ^c 2% weight loss; ^d Obtained by helium pycnometry for uncross-linked HBPAEKs, error represents the standard deviation; ^e Error represents the 95% confidence interval h. THERMAL PROPERTIES

[00274] HBPAEKs are, like their linear analogue, thermally very stable. In FIG. 15A-C, the weight loss as function of temperature of the uncross-linked and crosslinked HBPAEKs is shown. All HBPAEKs show an initial weight loss starting around 270 °C, which corresponds to the post-condensation process, where fluorine and hydroxyl groups react and release HF. Outgassing of small MW fractions start at temperatures above 400 °C, shown by the decrease in mass. Without wishing to be bound by theory, the degradation of small MW fractions is proposed to cause the difference amongst the three compounds, where the HBPAEK having the highest amount of PEP groups also shows the highest abundance of lower molecular weight molecules, which is supported by the SEC curves of FIG. 14.

[00275] In FIG. 15A-C, an increase in thermal stability is observed for the HBPAEK-28K- 10PEP and HBPAEK-25K-20PEP when these materials are cured at 280-350 °C, whereas the neat HBPAEK did not show an improvement in thermal stability upon curing. Without wishing to be bound by theory, this is probably caused by the crosslinking of the lower molecular weight fractions which are, after curing, part of the network structure.

[00276] Referring to FIG. 15A-C, weight loss as function of temperature for HBPAEK- 33K (FIG. 15 A), HBPAEK-28K-10PEP (FIG. 15B), and HBPAEK-25K-20PEP (FIG. 15C) are shown. The solid lines represent the uncured polymers, and the dashed lines the cured polymers (cured under program lh@280°C+lh@350°C). [00277] Glass transition temperature. The glass transition temperature, T , of the uncross- linked HBPAEKs was measured by DSC and the curves are shown in FIG. 16. The T_g for the neat HBPAEK is 155 °C. Introducing PEP end-groups results in a significant increase (up to 46 °C) in T . A change in T when the end-groups are replaced is recurrently observed for HBPs in literature. For example, Hawker demonstrated a T_g range of 97-290 °C with hyperbranched poly(ether ketones) (Hawker, C. J. & Chu, F. Hyperbranched Poly(ether ketones ): Manipulation of Structure and Physical Properties. Macromolecules 29, 4370-4380 (1996)) and Webster a range of 96-238 °C hyperbranched polyphenylenes (Kim, Y. H. & Webster, O. W. HYPERBRANCHED POLYPHENYLENES. Macromolecules 25, 5561- 5572 (1992); Kim, Y. H. & Beckerbauer, R. Role of End Groups on the Glass Transition of Hyperbranched Polyphenylene and Triphenylbenzene Derivates. Macromolecules 27, 1968- 1971 (1994)).

[00278] Referring to FIG. 16, DSC curves (endo down) showing the glass transition temperatures of uncross-linked HBPAEK-33K, HBP AEK-28K- 10PEP, and HBPAEK-25K- 20PEP, as first heat, 20 °C/min under N2 atmosphere are shown.

[00279] This increase is in sharp contrast with the properties of the end-capped HBPAEK described herein above; however, the synthesis route is different and an increased amount of intra molecular bonding (loops) from the prolonged reaction time and higher reaction temperature might be the reason for this. i. FILM THICKNESS AND REFRACTIVE INDEX AS FUNCTION OF HEAT TREATMENT

[00280] FIG. 17A shows the relative thickness and FIG. 17B the refractive index as a function of time for HBPAEK-28K-10PEP cross-linked at 280-350 °C. The thickness of the polymer film increases during heating to 280 °C due to thermal expansion. The temperature at which the change in the slope occurs, represents the T_g. While the temperature is constant at 280 °C, the polymer shows a little overshoot in the thickness due to the thermal expansion directly followed by a decrease in thickness because of densification during cross-linking.

The same effect is visible while heating to 350 °C, but more pronounced due to the higher temperature. Upon cooling, the material shrinks, and shows a T_g at a much higher temperature due to the cross-linking of the material. The final film thickness has decreased by 3% after cross-linking due to compaction.

[00281] Opposite to the thickness, the refractive index of the HBPAEK film decreases upon heating due to thermal expansion. While the refractive index is more or less constant during the first isothermal hold at 280 °C, it increases by 0.5% at the 350 °C isothermal hold due to cross-linking of the phenylethynyl functionalities. The final refractive index is unchanged compared to the index of the uncross-linked polymer. The changes in the thickness are relatively small, and the refractive index data is less accurate than the thickness, therefore small structural changes are not shown in the refractive index data. The data for HBPAEK-33K and HBPAEK-25K-20PEP were collected using a similar procedure and the graphs are shown in FIG. 18A-B and FIG. 19A-B, respectively.

[00282] Referring to FIG. 17A and FIG. 17B, the thermal behaviour of HBPAEK-28K- 10PEP using the 280-350 °C temperature program is shown. Specifically, relative thickness as function of time (FIG. 17 A) and relative refractive index as function of time (FIG. 17B) are shown. The second y-axis represents the temperature for both graphs.

[00283] Referring to FIG. 18A and FIG. 18B, the thermal behaviour of HBPAEK-33K using the 280-350 °C temperature program is shown. Specifically, relative thickness as function of time (FIG. 18 A) and relative refractive index as function of time (FIG. 18B) are shown. The second y-axis represents the temperature for both graphs.

[00284] Referring to FIG. 19A and FIG. 19B, the thermal behaviour of HBPAEK-25K- 20PEP using the 280-350 °C temperature program is shown. Specifically, relative thickness as function of time (FIG. 19A) and relative refractive index as function of time (FIG. 19B) are shown. The second y-axis represents the temperature for both graphs.

[00285] The linear coefficient of thermal expansion (CTE) can be calculated using:

where a is the linear coefficient of thermal expansion (°C ¹ ). d the initial thickness (m), d d the change in thickness (m), and d T the change in temperature (°C). The CTE can be extracted from the slope of the thickness versus time when above the T_g. The values of the thickness and temperature were obtained for both the heating and cooling phase. The initial temperature was defined as 7_max-80. and the final temperature as 7-_ma -5. The initial and final thicknesses were obtained at these temperatures. FIG. 20 shows an example of the data points chosen. All red points represent the data for the CTE at heating, and the blue points at cooling. The squares correspond to the thickness data, and the circles to the temperature data.

[00286] Referring to FIG. 20, the determination of the data points used to calculate the linear coefficient of thermal expansion. The initial temperature was defined 80 degrees below the maximum temperature, and the final temperature 5 degrees below the maximum temperature.

[00287] Although there is a relative large spread in the CTE between the three HBPAEKs studied, the CTE is always significantly larger upon cooling compared to heating (Referring to Table 10,). Without wishing to be bound by theory, this indicates that during the heating phase, there is already compaction of the material because of crosslinking, and thus that cross-linking is already occurring during heating of the polymer.

[00288] Referring to Table 10, the linear coefficient of thermal expansion of HBPAEK- 33K, HBP AEK-28K- 10PEP, and HBPAEK-25K-20PEP, measured by SE is detailed. The average of two samples was taken.

TABLE 10.

J· SPECTROSCOPIC ELLIPSOMETRY

[00289] To study the effect of post-condensation and cross-linking of PEP on the T and EFFV, the change in film thickness and refractive index of HBPAEK films were measured by in-situ spectroscopic ellipsometry (SE) equipped with a heating stage. The polymers were heated using two different temperature programs, which enabled the investigation of how the cross-linking temperature affects the thermal and optical properties. The films were either heated to 280 °C, with a 1 hour dwell or heated to subsequently 280 °C and 350 °C with a 1 hour dwell at both isothermal stages. The temperature profiles are plotted as a function of time in FIG. 13A and FIG. 13B. Additionally, the coefficients of thermal expansion were derived with SE, using the thickness versus temperature slope. The glass transition temperature (T_g) and excess free fractional volume (EFFV) of the polymers can be obtained from these SE data (Ogieglo, W., Wormeester, H., Wessling, M. & Benes, N. E. Effective medium approximations for penetrant sorption in glassy polymers accounting for excess free volume. Polymer (Guildj). 55, 1737-1744 (2014)). [00290] FIG. 21 graphically illustrates the dependence of the T for all HBPAEKs upon cross-linking. The values shown are the average taken of at least two individual

measurements, where the absolute difference in T_g between the measurements was always smaller than 3 °C.

[00291] Referring to FIG. 21, the change in T_g as a function of the cross-link temperature for the different HBPAEKs studied measured by in situ SE is shown. The arrows indicate the change in T_g before and after cross-linking. The temperature program is mentioned above the corresponding arrow and refers to an isothermal hold at that temperature.

[00292] The T_g of all polymers increases with cross-linking due to the reduced chain mobility and is clearly related to the amount of PEP cross-linker. Introducing alkyne end- groups increases the T_g to 172 °C and can reach values of up to 250 °C after curing. The initial values of the T_g for the uncross-linked HBPAEKs obtained by ellipsometry are lower compared to those obtained by DSC (FIG. 16), although the trend is similar. This difference originates from the difference in measurement technique, since the absolute value of the T_g is dependent on this.

[00293] When the polymers are heated to 280 °C, a post-condensation process starts, resulting in a relatively small increase in T for all polymers. This curing starts around 270 °C, based on rheology data detailed herein above, and will continue with increasing the temperature. At temperatures above 300 °C, the alkyne groups of the PEP end-groups start to cross-link. The temperature program towards 350 °C results in a more pronounced effect on the T , as the T increases at least 35% compared to the uncross-linked polymer. The effect on the HBPAEKs without the alkyne groups is limited, as the T_g will only increase marginally due to the post-condensation, as no alkyne groups are present. When comparing polymers with and without PEP, it is concluded that alkyne cross-linking has the largest contribution to the increase in T_g.

[00294] Similar to the T_g, the EFFV of the polymers could be calculated from the SE temperature dependent data by using the following equation:

where ho_G is the glassy thickness and h*_DL (D for dilation) the extrapolated liquid thickness (Ogieglo, W., Wormeester, H., Wessling, M. & Benes, N. E. Effective medium

approximations for penetrant sorption in glassy polymers accounting for excess free volume. Polymer (Guildj). 55, 1737-1744 (2014)). FIG. 22 shows the EFFV for all polymers before and after thermal treatment. The same trend is observed for the EFFV as for the T : cross- linking the HBPAEK results in an increase in EFFV.

[00295] Referring to FIG. 22, the change in EFFV as a function of the cross-link temperature for the different HBPAEKs studied measured by in situ SE is shown. The arrows indicate the change in EFFV before and after cross-linking. The temperature program is indicated above the corresponding arrow and refers to an isothermal hold at that temperature.

[00296] A more significant increase in EFFV is observed when HBPAEKs with alkyne end-groups are cross-linked. When the T_g is increased due to cross-linking, the polymer will be in the glassy state at a higher temperature, thus at an earlier point in time when cooling down. Therefore, the EFFV will be higher when cooled down to room temperature, as schematically shown in FIG. 23. PEP containing HBPAEKs that are cured at 280 °C are found to have a higher EFFV as compared to cured neat HBPAEKs, which stresses the effect of introducing different end-groups on the EFFV of a hyperbranched polymer.

[00297] Referring to FIG. 23, a simplified schematic representation of the excess fractional free volume (EFFV) of a polymer is shown. Without wishing to be bound by theory, this volume is considered as the space between polymer chains.

[00298] HBPAEKs bearing PEP end-groups have an EFFV of up to 9.5% after curing at 280-350 °C. This is relatively high compared to other glassy polymers such as polyetherimide (7%) and polysulfone (6.6%), but lower than Matrimid (12%) (data from unpublished work). Due to their high T_g and EFFV, the PEP containing HBPAEKs were further analysed for their CO2 sorption behaviour and gas separation performance.

[00299] CO sorption. The high T_g and high EFFV of the HBPAEK-28K- 10PEP and HBPAEK-25K-20PEP that were discussed in the previous paragraph, showed that these compounds had the highest potential to be used as gas separation membranes. High-pressure CO2 sorption measurements were conducted on these materials to measure the effect of CO2 gas on these membranes. FIG. 24A-C shows the swelling (FIG. 24A), relative refractive index (FIG. 24B), and adsorbed concentration of CO2 as a function of the CO2 pressure (FIG. 24C) for HBPAEK-28K-10PEP that was cross-linked at 280-350 °C prior to the sorption measurements. Similar results were obtained for the HBPAEK-25K-20PEP and are presented in FIG. 25A-C.

[00300] Referring to FIG. 24A-C, CO2 sorption (O) and desorption (□) for HBPAEK- 28K-10PEP, at pressures up to 60 bar are shown. Specifically, the swelling degree (FIG. 24A), the relative refractive index (FIG. 24B), and the concentration of CO2 as function of pressure (FIG. 24C) are shown.

[00301] Referring to FIG. 25A-C, CO2 sorption (O) and desorption (□) for HBPAEK- 25K-20PEP, at pressures up to 60 bar are shown. Specifically, the swelling degree (FIG.

25 A), the relative refractive index (FIG. 25B), and the concentration of CO2 as function of pressure (FIG. 25C) are shown.

[00302] The obtained CO2 induced swelling isotherm has a typical shape for a glassy polymer (Visser, T., Koops, G. H. & Wessling, M. On the subtle balance between competitive sorption and plasticization effects in asymmetric hollow fiber gas separation membranes. J. Memb. Sci. 252, 265-277 (2005)) with swelling degrees in the same order as linear sulfonated PEEK (SPEEK) (4% at 50 bar) but lower than Matrimid® (6.5% at 50 bar) (Simons, K. et al. C02 sorption and transport behavior of ODPA-based polyetherimide polymer films. Polymer (Guildf). 51, 3907-3917 (2010)). The relative refractive index of the HBPAEK films initially increases with increasing CO2 pressures up to 60 bar, followed by a decrease in index with decreasing CO2 pressure. This initial increase in refractive index can be attributed to the filling of the EFFV by CO2 molecules, while at higher pressures the dilation of the polymer matrix results in a decrease (Ogieglo, W., Madzarevic, Z. P.,

Raaij makers, M. J. T., Dingemans, T. J. & Benes, N. E. High-Pressure Sorption of Carbon Dioxide and Methane in All-Aromatic Poly ( etherimide ) -Based Membranes. J. Polym. Sci. Part B Polym. Phys. 54, 986-993 (2016); Raaijmakers, M. J. T. et al. Sorption Behavior of Compressed C02 and CH4 on Ultrathin Hybrid Poly(POSS-imide) Layers. ACSAppl. Mater. Interfaces 7, 26977-26988 (2015)). To what extent the index initially increases seems to be dependent on the EFFV. For example, HBPAEK-28K-10PEP that is uncured has a lower EFFV and, therefore, a lower initial increase in refractive index. It is noted that the absolute changes in refractive index are extremely low, and in combination with a low sensitivity towards the refractive index, the data displays a trend instead of accurate numbers.

[00303] From the thickness and refractive index, the concentration of CO2 in the polymer matrix was derived, as shown in FIG. 24C. There is an initial steep increase in CO2 concentration due to filling of the EFFV, while at higher CO2 pressures the sorption is limited by the dilation of the polymer network, and therefore the slope decreases.

[00304] The HBPAEK-28K-10PEP shows a strong hysteresis between sorption and desorption for both the swelling and refractive index data. This originates from polymer chain reorganizations at the time scale of the measurements despite the cross-linking of the polymer. The relative refractive index drops below 1 at vacuum after desorption, indicating that the polymer structure is changed due to dilation. The same behaviour is found in, for example, Matrimid® (Raaijmakers, M. J. T. et al. Sorption Behavior of Compressed C02 and CH4 on Ultrathin Hybrid Poly(POSS-imide) Layers. ACSAppl. Mater. Interfaces 7, 26977- 26988 (2015)) and other poly(ether imide)s (Ogieglo, W., Madzarevic, Z. P., Raaijmakers,

M. J. T., Dingemans, T. J. & Benes, N. E. High-Pressure Sorption of Carbon Dioxide and Methane in All- Aromatic Poly ( etherimide ) -Based Membranes. J. Polym. Sci. Part B Polym. Phys. 54, 986-993 (2016)).

[00305] Plasticization. The glass transition temperature (T_g) of a polymer greatly affects the performance as a membrane. Above the T_g, the chains become more mobile, often resulting in a loss of selectivity. The frequently used polyimides have, among various other good properties, very high T_gs and are therefore the best performing materials to date.

However, a process called plasticization is affecting the performance in a negative way and this happens not only in polyimides, but also in poly(ether imide)s. In the presence of CO2, these polymers tend gain mobility this reduces the selectivity. A method to reduce this effect was the introduction of crosslinked polymers. By crosslinking the chain mobility is significantly reduced and it was found to have a positive effect on stability, physical ageing and plasticization. The downside of this method is that it is often accompanied with a decrease in permeability.

[00306] From the sorption isotherm the onset of plasticization could be determined as the point where the isotherm shows a steep linear increase with CO2 pressure. In addition to this steep linear increase, no hysteresis between sorption and desorption is observed in the case of plasticization. The sorption isotherms for the HBPAEKs show no increase in slope up to pressures of 50 bar CO2 and, thus, it is concluded that no plasticization occurs at CO2 pressures up to at least 50 bar (see FIG. 24A-C). After this point the slope of the sorption isotherm seems to increase, however, the signal noise and therefore errors at these extreme pressures are relatively large, making it impossible to conclude from this data the presence or absence of plasticization at pressures above 50 bar. This lack of plasticization is in great contrast to often used linear polymers for gas separation (Bos, a., Punt, I. G. M., Wessling,

M. & Strathmann, H. C02 -induced plasticization phenomena in glassy polymers. J. Memb. Sci. 155, 67-78 (1999)). k. CONTACT ANGLE MEASUREMENTS

[00307] FIG. 26 shows the contact angle results for the 3 HBPAEK films on silicon wafers measured with the sessile drop method using Mili-Q water. From these data it cannot be concluded that there is a difference in contact angle between the different HBPAEKs and the uncross-linked or cross-linked state. The average contact angle varies between 95° and 103°, indicating the hydrophobic character of the HBPAEKs. The values are similar to earlier reported contact angles for comparable aromatic hyperbranched polymers with fluorine groups (Mueller, A., Kowalewski, T. & Wooley, K. L. Synthesis, characterization, and derivatization of hyperbranched polyfluorinated polymers. Macromolecules 31, 776-786 (1998)).

[00308] Referring to FIG. 26, the contact angle of uncross-linked and cross-linked (temperature program 280-350 °C) HBPAEK films on silicon wafers is shown. The error bars represent the 95% confidence interval determined over 5 measurements.

1. WATER SORPTION

[00309] Gas separation membranes can suffer from the presence of water vapour in the feed stream. Water can swell a polymer and this will reduce the selectivity. FIG. 27A and FIG. 27B shows the relative thickness (FIG. 27A) and relative refractive index (FIG. 27B) for HBPAEKs containing 10% PEP (□) and 20% PEP (O) cross-linked at 350 °C as a function of relative humidity, measured by SE. The PEP end-capped HBPAEKs show very little swelling in water vapour. There is a slight increase in relative refractive index, due to the replacement of void ( n = 1.00) with water (n = 1.33).

[00310] The experimental set-up was limited to 50% relative humidity, but the relative thickness is not expected from the data to exceed 0.3%.

[00311] In sum, it has been demonstrated that it is possible to spin-coat the soluble neat and PEP end-capped HBPAEKs on a alumina substrate to give access to very thermally stable and robust polymer thins films with potential as gas separation membranes. These all aromatic hyperbranched polymers are completely amorphous and the absence of crystallinity aids the processing and potential membrane flux. Thermally crosslinking the PEP end-groups significantly increased the T_g from 150 to 250 °C and the EFFV from 4 to 9.5%. The films showed very little swelling in CO2 or water and no signs of plasticization were visible up to 50 bars of CO2. Furthermore, remaining fluorine end-groups can be used for further modification and tuning of the final properties of the hyperbranched polymer network. This hyperbranched polymer approach reveals a pathway to use high performance polymers in membrane science due to the increased solubility and processability.

3. GAS SEPARATION PERFORMANCE OF CROSSLINKED HBPAEK MEMBRANES

[00312] Here, the activation energies for ¾, He, N2, CO2 and CH4 were measured, the selectivity for the commonly used gas mixtures H2/CO2, H2/N2, H2/CH4 and CO2/CH4 for both the uncured and cured HBPAEK-28K-10PEP and HBPAEK-25K-20PEP were determined, and the selectivity measured at an elevated temperature (200 °C) for a prolonged period of time. This is graphically shown in FIG. 28.

[00313] Without wishing to be bound by theory, a wide operating temperature range for membranes is desirable, as energy can be saved if gases no longer need to be cooled before the separation to match the operating parameters of the membranes (Li, X., Singh, R. P., Dudeck, K. W., Berchtold, K. A. & Benicewicz, B. C. Influence of polybenzimidazole main chain structure on H 2 /CO 2 separation at elevated temperatures. J. Memb. Sci. 461, 59-68 (2014)). a. MEMBRANE PREPARATION AND ANALYSIS

[00314] HBPAEK-28K-10PEP and HBPAEK-25K-20PEP were used and their syntheses as described herein above. They were annealed at 200 °C for 30 minutes before they were cured according to the temperature profile show in FIG. 29. Referring to FIG. 29, the spin- coated HBP AEK-28K- 10PEP and HBPAEK-25K-20PEP films were cured for lh at 280 °C and lh at 350 °C.

[00315] Membrane Sinsle Gas Permeation Measurements. Single gas (He, H2, CO2, N2, and CH4) permeation measurements were performed using a custom build setup

(Convergence, the Netherlands). All experiments were performed in dead-end mode at a transmembrane pressure of 2 bar. The membrane module was heated to temperatures between 50 and 200 °C. At least two individual membranes were measured for each polymer and cross-link program.

[00316] Long-term stability test. The long-term stability of a cured HBPAEK-28K-10PEP membrane was tested by measuring alternating the hydrogen and nitrogen permeance at 200 °C for two weeks. The nitrogen permeance was measured for 5.5 hours, after which the feed gas was switched to hydrogen for 30 minutes. The reported permeance was defined as the average permeance during the last 5 minutes for every step. b. SINGLE GAS PERMEATION THROUGH THE ALUMINA SUPPORT

[00317] The gas permeation through the alumina support must be determined before the gas separation properties of the crosslinked HBPAEK films can be measured. FIG. 30A and FIG. 30B show the single gas permeation characteristics of the alumina support. The pore size of the g-alumina allows for separation by Knudsen diffusion (Uhlhom, R. J. R., Keizer, K. & Burggraaf, A. J. Gas and surface diffusion in modified g-alumina systems. J. Memb. Sci. 46, 225-241 (1989)). Knudsen diffusion describes molecules passing through very narrow pores with a diameter of <50 nm. This results in a condition where gas molecules more often collide with the pore walls than with each other, a process that is also called Knudsen flow. The size of the molecules determines the amount of interaction with the pore wall, resulting in a gradient in flow and thus opportunity for separation.

[00318] Referring to FIG. 30A and FIG. 30B, single gas permeation results for the bare alumina membrane support are shown. The difference in kinetic diameter gives a difference in permeance (FIG. 30A). The selectivity for the bare substrate is temperature independent (FIG. 30B).

[00319] The selectivity in the case of Knudsen diffusion can be calculated by:

where _a/b is the selectivity (-) of the membrane and M_a and A are the molar mass of the gas molecules a and b (g/mol), respectively. All values are in good agreement with the theoretical Knudsen selectivity that are shown in Table 11, except that of H2/CO2. Without wishing to be bound by theory, this may be due to the condensability of CO2.

TABLE 11.

[00320] The adsorbed CO2 molecules onto the pore wall can move by surface diffusion, resulting in an increased CO2 permeability and therefore reduced selectivity (Richardson, J. J., Bjommalm, M., Caruso, F. & Baker, R. W. Membrane Technology and Applications . Membrane Technology 348, (John Wiley & Sons, Ltd, 2012)). c. PREPARING CROSSLINKED HBPAEK MEMBRANES

[00321] The HBPAEK polymers were spin-coated onto a porous alumina support and thermally crosslinked before they were tested for their membrane performance. FIG. 31 shows a scanning electron micrograph of the cross-section of such a cross-linked HBPAEK- 28K-10PEP film. Three layers can be distinguished: the bottom layer is >2 mm thick a- alumina layer (pore size -100 nm, porosity -30%), the middle later with approximately 3 pm thick g-alumina (pore size -3 nm, porosity -40%) and the top layer is a -700 nm thick HBPAEK film. The film thicknesses of all samples are assumed to be 700 nm, due to the identical spin-coating procedure for all samples. To remove anisotropy induced by spin coating, all samples were heated to 200 °C for 30 minutes. Uncross-linked membranes as well as cross-linked membranes that were cured for lh at 280 °C and lh at 350 °C were tested for their single gas permeation characteristics.

[00322] Referring to FIG. 31, cross-section scanning electron micrograph of a cross-linked HBPAEK-28K-10PEP film atop of a ceramic support is shown. The ceramic support is made of an a-alumina support with a 3 pm thick g-alumina layer. A top of this g-alumina layer sits the 700 nm thick HBPAEK film. d. GAS SEPARATION PERFORMANCE OF CROSSLINKED HBPAEK MEMBRANES

[00323] The gas separation performance for HBPAEK-28K-10PEP and HBPAEK-25K- 20PEP are shown in FIG. 32 and FIG. 33, respectively. The single gas permeance as a function of gas kinetic diameter for the uncured HBPAEKs is given in panels (a), and for the HBPAEKs cured for lh at 280 °C and lh at 350 °C in panels (d). Due to the lower T_g of the uncured HBPAEKS, the maximum temperature was set to 150 °C instead of 200 °C. For both HBPAEK-28K-10PEP and HBPAEK-25K-20PEP it was found that the single gas permeance decreases with increasing gas kinetic diameter. This is a typical trend observed for glassy polymers, indicating a sieving mechanism. With increasing temperature, the permeance increased due to the increased mobility of a gas at higher temperatures.

[00324] The Arrhenius plot of the ln(permeance) as a function of T ¹ is shown in FIG. 32 and FIG. 33, panels (b). The activation energy of the gas transport could be derived from the slope of this plot for every measured gas. Table 12 shows the values of the activating energy for all HBPAEKs and gases. The constant slopes of the activating energy suggest that the HBPAEK films do not suffer from temperature induced chain mobility.

[00325] Referring to FIG. 32, gas permeation for uncross-linked HBPAEK-28K-10PEP (panels (a)-(c)) and cross-linked HBPAEK-28K-10PEP (lh at 280 °C and lh at 350 °C) (panels (d)-(f)) are shown. Specifically, permeance as function of the gas kinetic diameter is shown in panels (a) and (d), an Arrhenius plot of single gas permeances is shown in panels (b) and (e), and ideal selectivity of Eh/CEE, H2/N2, H2/CO2, and CO2/CH4 as function of temperature is shown in panels (c) and (1). All error bars represent the standard error.

[00326] Referring to FIG. 33, gas permeation for uncross-linked HBPAEK-25K-20PEP (panels (a)-(c)) and cross-linked HBPAEK-25K-20PEP (lh at 280 °C and lh at 350 °C) (panels (d)-(f)) are shown. Specifically, permeance as function of the gas kinetic diameter is shown in panels (a) and (d), an Arrhenius plot of single gas permeances is shown in panels (b) and (e), and ideal selectivity of H2/CH4, H2/N2, H2/CO2, and CO2/CH4 as function of temperature is shown in panels (c) and (1). All error bars represent the standard error.

[00327] In general, the activation energy is similar for all gases and membranes. Typically used fluorine rich polymers, e.g., polyimides containing trifluoromethyl (CF3) groups, show a low activation energy for CO2 transport due to the high solubility of CO2 in the membrane matrix at lower temperatures. At higher temperatures the CO2 solubility decreases, while the diffusivity increases. The permeability is the product of solubility and diffusivity and, therefore, this effect is cancelled out at elevated temperatures. Studies on 6FDA-based polyimides show that the CO2 permeability was constant or even decreases with increasing temperature while for other gases the permeability increases with temperature (Duthie, X. et al. Operating temperature effects on the plasticization of polyimide gas separation membranes. J. Memb. Sci. 294, 40-49 (2007); Lin, W. H. & Chung, T. S. Gas permeability, diffusivity, solubility, and aging characteristics of 6FDA-durene polyimide membranes. J. Memb. Sci. 186, 183-193 (2001)). Polyimides without these CF3 groups showed also an increase in permeability with temperature for CO2 (Villaluenga, J. P. G., Seoane, B., Hradil,

J. & Sysel, P. Gas permeation characteristics of heterogeneous ODPA-BIS P polyimide membranes at different temperatures. J. Memb. Sci. 305, 160-168 (2007)). The activating energy for CO2 transport does not differ from the other gases for the HBPAEK films measured in this study. The fluorine groups of the HBPAEKs show no increased affinity for CO2 in the gas separation measurements, hinting that fluorine atoms only display an effect when employed as bulky groups (e.g., in -CF3 groups). However, there is still a lot of debate on the nature of the CO2-F interaction (Raveendran, P. & Wallen, S. L. Exploring C02- philicity: Effects of stepwise fluorination. J. Phys. Chem. B 107, 1473-1477 (2003); Singley, E. J., Liu, W. & Beckman, E. J. Phase behaviour and emulsion formation of novel fluoroether amphiphiles in carbon dioxide. Fluid Phase Equilib. 128, 199-219 (1997)).

[00328] The ideal selectivity (Ra/Rb) of H2/CH4, H2/N2, H2/CO2, and CO2/CH4 gas pairs as function of temperature is shown in FIG. 32 and FIG. 33, panels (c). Without wishing to be bound by theory, it is theorized that all membranes are still selective at higher temperatures up to 200 °C. Independent of temperature, the selectivity of H₂/CH₄ and H₂/N₂ is higher compared to that of H₂/CO₂ and CO₂/CH₄, which agrees with the molecular sieving mechanism. The selectivity of uncured HBPAEK over the cured HBPAEKs is minimal, with the exception of CO₂/CH₄. The advantage though is the increased temperature window, as the T_g of the cured polymers is higher.

[00329] The selectivity of HBPAEK-28K-10PEP is comparable to the HBPAEK-25K- 20PEP, which indicates that addition of the 10% PEP crosslinker is beneficial for the T_g, but an increased amount, i.e., 20%, does not contribute to a better gas separation performance.

TABLE 12.

[00330] The performance was compared with Matrimid®, one of the polyimides that are currently the best performing gas separation membranes and are relatively easy to prepare form diamines and dianhydrides. The T_g of Matrimid® easily exceeds 250 °C, while additional bulky side groups prevent efficient chain packing and, thus, reduce crystallinity and increase free volume. The disadvantage of Matrimid® is the susceptibility to

plasticization, an issue that is envisioned to be less of a problem for HBPAEKs, as the branched systems will be crosslinked and very rigid. Matrimid® is often used as a bench mark and, therefore, useful to put the performances into perspective. [00331] When the performance of the HBPAEKs measured at 50 °C was compared with the linear polyimide Matrimid®, measured at 35 °C there are some interesting differences. While the selectivity of H2/CH4 and H2/N2 of our HBPAEKs are comparable to those found for Matrimid® (64 and 56, respectively), the CO2/CH4 selectivity is lower compared to Matrimid® (36). Additionally, the selectivity of H2/CO2 is much higher as compared to Matrimid® (1.8) (Sanders, D. F. et al. Energy-efficient polymeric gas separation membranes for a sustainable future : A review. Polymer (Guildj). 54, 4729-4761 (2013)). Fang et al. (2001) reported the synthesis and membrane performance of hyperbranched polyimide membranes (Fang, I, Kita, H. & Okamoto, K. Gas permeation properties of hyperbranched polyimide membranes. J. Memb. Sci. 182, 245-256 (2001)). The authors report that besides the end-groups, the cross-linking mechanism of a hyperbranched polymer has a great influence on the membrane performance. In general, their measured CO2 permeabilitiy is comparable (1-4 Barrer) up to significantly higher (65 Barrer) as compared to the HBPAEKs (1-4 Barrer). The relatively low CO2 permeability found for our HBPAEKs fit very well with the low swelling degrees measured by in situ SE as detailed herein above.

[00332] In addition, their CO2/CH4 selectivity is much higher (41-61) compared to that of the HBPAEKs (4-19) (Fang, J., Kita, H. & Okamoto, K. Gas permeation properties of hyperbranched polyimide membranes. J. Memb. Sci. 182, 245-256 (2001)). The work of Suzuki et al. (2004) showed the CO2 permeability of another hyperbranched polyimide. They report either comparable or up to 3 times better CO2 permeability compared to the best disclosed HBPAEK (Suzuki, T., Yamada, Y. & Tsujita, Y. Gas transport properties of 6FDA- TAPOB hyperbranched polyimide membrane. Polymer (Guildf). 45, 7167-7171 (2004)). To compare the performance of the HBPAEKs membranes to other membranes available, their performance was plotted in the Robeson plots. e. ROBESON PLOTS

[00333] Robeson plots are used in membrane science to display the trade-off relationship between selectivity and permeability (Robeson, L. M. The upper bound revisited. J. Memb. Sci. 320, 390-400 (2008)). This empirical upper bound relationship is displayed in a plot where the permeability (=permeance*thickness) is reported on the x-axis and the selectivity on the y-axis (Koros, W. J. & Woods, D. G. Elevated temperature application of polymer hollow-fiber membranes. J. Memb. Sci. 181, 157-166 (2001)). The permeances were measured at 50 °C and the thickness was assumed to be 700 nm for each membrane. From the Robeson plots in FIG. 34 it can be seen that the disclosed HBPAEKs are far below the present upper limit for CO2/CH4 and H2/N2 gas pairs. However, the H2/CH4 gas pair is close to the 1991 upper bound, and the H₂/CO₂ gas pair is even at the present upper bound for the cross-linked HBPAEK-28K-1 OPEP and HBPAEK-25K-20PEP membranes.

[00334] Referring to FIG. 34, Robeson plots for CO2/CH4 (panel (a)), H2/N2 (panel (b)), H2/CO2 (panel (c)), and H2/CH4 (panel (d)) gas pairs with their permeabilities, obtained from the permeances measured at 50 °C are shown. The thickness of the separating layer was assumed to be 700 nm for all membranes. The theoretical upper bound as in 1991 (dashed line) and 2008 (solid line) (Robeson, L. M. The upper bound revisited. J. Memb. Sci. 320, 390-400 (2008)) were plotted as reference. The symbols represent: HBPAEK-28K-10PEP uncross -linked (0), HBPAEK-28K- 1 OPEP cross-linked (□), HBPAEK-25K-20PEP uncross- linked (^), and HBPAEK-25K-20PEP cross-linked (°). f. LONG-TERM PERFORMANCE AT HIGH TEMPERATURE

[00335] Most state-of-the-art polymeric membranes show a decline in membrane performance at elevated temperatures caused by an increase in macromolecular dynamics (Koros, W. J. & Woods, D. G. Elevated temperature application of polymer hollow-fiber membranes. J. Memb. Sci. 181, 157-166 (2001)). The development of a membrane stable at elevated temperatures would be of great interest to industry. Because of their excellent thermal stability, HBPAEK membranes showed to be still selective at temperatures up to 200 °C (the experimental limit of the apparatus used). To further study their excellent thermal stability, the gas separation performance of a cured HBPAEK-28K-10PEP was taken as an example and was studied for 2 weeks at 200 °C. As can be concluded from FIG. 35A and FIG. 35B, HBPAEK-28K-10PEP did not show any sign of degradation by the loss of performance, indicating the great potential of these materials for gas separation at elevated temperatures.

[00336] Referring to FIG. 35A and FIG. 35B, the long-term thermal stability of cured HBPAEK-28K-10PEP, kept at 200 °C is shown. Specifically, FIG. 35A shows the permeance of H2 and N2 as a function of time and FIG. 35B shows the H2/N2 selectivity as function of time. No decrease in selectivity was observed after 14 days.

[00337] In sum, HBPAEK-28K-1 OPEP and HBPAEK-25K-20PEP were evaluated for their gas separation performance. The HBPAEK films were spin-coated on an alumina substrate and were visualized with scanning electron microscopy, showing a layer thickness of 700 nm. The activation energy for the used gasses, i.e., He, ¾, N₂, CH₄ and CO₂, showed minor differences between them and ranged from 14-29 KJ/mol. The first membranes performance results of the HBPAEK membranes show a moderate overall selectivity for the used gas mixtures, where the H2/CO2 selectivity is already competitive with other commonly used membranes. The selectivity of the uncured polymer could be measured to 150 °C, whereas the cured polymers could be measured at 200 °C as well due to a higher initial T . The cured hyperbranched PAEK backbones show excellent stability at elevated temperatures for a prolonged period of time, as the selectivity and permeance remain unaffected at 200 °C for up to 2 weeks with no indication of a decrease after this time.

4. CROSSLINKED HYPERBRANCHED PAEKS GAS TRANSPORT DATA

[00338] Robeson upper bound plots for H2/CO2 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-69K end-capped with 10% PEP and 20% PEP are illustrated in FIG. 36A and FIG. 36B, respectively, and the corresponding data is detailed in Tables 13A and 13B below.

TABLE 13A.

TABLE 13B.

[00339] Robeson upper bound plots for H₂/CH₄ gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-69K end-capped with 10% PEP and 20% PEP are illustrated in FIG. 37A and FIG. 37B, respectively, and the corresponding data is detailed in Tables 14A and 14B below.

TABLE 14A.

TABLE 14B.

[00340] Robeson upper bound plots for H2/N2 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-69K end-capped with 10% PEP and 20% PEP are illustrated in FIG. 38A and FIG. 38B, respectively, and the corresponding data is detailed in Tables 15A and 15B below. TABLE 15A.

TABLE 15B.

[00341] Robeson upper bound plots for N₂/CH₄ gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-69K end-capped with 10% PEP and 20% PEP are illustrated in FIG. 39A and FIG. 39B, respectively, and the corresponding data is detailed in Tables 16A and 16B below.

TABLE 16A.

TABLE 16B.

[00342] Robeson upper bound plots for CO₂/CH₄ gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-69K end-capped with 10% PEP and 20% PEP are illustrated in FIG. 40A and FIG. 40B, respectively, and the corresponding data is detailed in Tables 17A and 17B below.

TABLE 17A.

TABLE 17B.

[00343] Robeson upper bound plots for CO2/N2 gas pairs illustrating permeation for uncrosslinked and crosslinked HBPAEK-69K end-capped with 10% PEP and 20% PEP are illustrated in FIG. 41 A and FIG. 41B, respectively, and the corresponding data is detailed in Tables 18A and 18B below.

TABLE 18A.

TABLE 18B.

[00344] In sum, the H2/CO2 data exceeds the Robeson 2008 Upper Bound, H2/CH4 and H2/N2 are competitive with other materials near the upper bound, and N2/CH4, CO2/CH4, and CO2/N2 are somewhat far from the upper bound. The permeability’s generally increase with temperature. In addition, selectivity’s generally decrease with temperature, with a few exceptions.

[00345] The foregoing is illustrative of the present invention, and is not to be construed as limiting thereof. The invention is defined by the following claims, with equivalents of the claims to be included therein.

[00346] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. Other aspects of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

Claims

CLAIMS What is claimed is:

1. A hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having a phenylacetylene end group.

2. The polymer of claim 1, wherein the polymer has at least one residue having a halide end group.

3. The polymer of claim 2, wherein the halide end group is a fluoride end group.

4. The polymer of claim 1, wherein the hyperbranched polymer has at least one residue having a hydroxyl end group.

5. The polymer of claim 1, wherein the hyperbranched polymer has repeating units having a structure represented by a formula:

wherein n is the overall degree of polymerization and wherein n is an integer selected from 10-300; wherein R^x is selected from the group consisting of halogen and -OH; and wherein each of Ar^la and Ar^lb is independently selected from the group consisting of 6- membered aryl substituted with a phenylacetylene group, 6-membered heteroaryl substituted with a phenylacetylene group, and a structure represented by a formula:

6. The polymer of claim 1, wherein the poly(aryletherketone) backbone is a

polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a

polyetherketoneketone (PEKK) backbone.

7. The polymer of claim 1, wherein the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of from about 5 mol% to about 40 mol%.

8. The polymer of claim 1, wherein the at least one occurrence of Ar^la, Ar^lb, and Ar² is present in an amount of about 10 mol%.

9. The polymer of claim 1, wherein the at least one occurrence of Ar^la, Ar^lb, and Ar² is a structure represented by a formula selected from the group consisting of:

10. The polymer of claim 1, wherein the at least one occurrence of Ar^la, Ar^lb, and Ar² is a structure represented by a formula:

11. The polymer of claim 1 , wherein the polymer has a degree of branching of from about

0.3 to about 0.7.

12. The polymer of claim 1, wherein the polymer has a degree of branching of about 0.5.

13. The polymer of claim 1, wherein the polymer is amorphous.

14. The polymer of claim 1, wherein the polymer has a glass transition temperature (T_g) of from about 130 °C to about 200 °C.

15. The polymer of claim 1, wherein the polymer is at least 80% soluble at a temperature of from about 20 °C to about 25 °C in a solvent selected from tetrahydrofuran, chloroform, and N-methylpyrrolidinone.

16. The polymer of claim 1, wherein the polymer has an excess free fractional volume (EFFV) of up to about 10%.

17. The polymer of claim 1, wherein the poly(aryletherketone) backbone is a

polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a

polyetherketoneketone (PEKK) backbone, the at least one occurrence of Ar^la, Ar^lb, and Ar² is a structure represented by a formula:

18. A hyperbranched polymer network comprising the hyperbranched polymer of claim 1, wherein the hyperbranched polymer network is crosslinked via the phenylacetylene end group.

19. The hyperbranched polymer network of claim 18, wherein the hyperbranched polymer network has a crosslinking density of from about 50 mol/m³ to about 90 mol/m³.

20. The hyperbranched polymer network of claim 18, wherein the hyperbranched polymer network has a crosslinking density of from about 55 mol/m³ to about 80 mol/m³.

21. A method for making the hyperbranched polymer of claim 1 , the method comprising:

(a) providing a hyperbranched poly(aryletherketone) having at least one halide end group; and (b) reacting the hyperbranched poly(aryletherketone) with a monomer having a phenylacetylene group.

22. The method of claim 21, wherein providing is via polymerization of a monomer having a structure selected from the group consisting of:

23. The method of claim 21, wherein providing is via polymerization of a monomer having a structure:

24. A method for making the hyperbranched polymer network of claim 18, the method comprising crosslinking the hyperbranched polymer of claim 1.

25. The method of claim 24, wherein crosslinking is via applying heat.

26. The method of claim 25, wherein applying heat is applying a temperature of from about 200 °C to about 400 °C.

27. The method of claim 25, wherein applying heat is applying a temperature gradient ranging from about 200 °C to about 400 °C.

28. A hyperbranched polymer having a poly(aryletherketone) backbone and at least one residue having an end group selected from the group consisting of phenylacetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine, wherein the end group is present in an amount of from about 5 mol% to about 40 mol%.

29. The hyperbranched polymer of claim 28, wherein the end group is phenylacetylene.

30. The hyperbranched polymer of claim 28, wherein the end group is present in an amount of about 10 mol%.

31. A hyperbranched polymer network comprising the hyperbranched polymer of claim 28, wherein the hyperbranched polymer is crosslinked via the end group.

32. An article comprising the hyperbranched polymer network of claim 18 or claim 31, wherein the article is selected from a polymer film, a thermoset, a polymer coating, an adhesive, and a thermoplastic resin.

33. The article of claim 32, wherein the article is a polymer film.

34. The article of claim 33, wherein the polymer film has a crosslinking density of from about 0.10 kmol/m³ to about 3.0 kmol/m³.

35. The article of claim 33, wherein the polymer film has a crosslinking density of from about 0.20 kmol/m³ to about 2.5 kmol/m³.

36. The article of claim 33, wherein the polymer film has a maximum tensile strength of from about 35 MPa to about 45 MPa at from about 1.5% to about 2.5% elongation.

37. The article of claim 33, wherein the polymer film has a maximum tensile strength of about 40 MPa at about 2% elongation.

38. The article of claim 33, wherein the polymer film has a storage modulus of from about 3 GPa to about 4 GPa at a temperature of from about 18 °C to about 25 °C.

39. The article of claim 33, wherein the polymer film has a thickness of from about 125 nm to about 175 nm.

40. The article of claim 33, wherein the polymer film has a thickness of about 150 nm.

41. The article of claim 33, wherein the polymer film is prepared via spin-coating.

42. The article of claim 32, wherein the article is a thermoset.

43. A membrane having a support and a polymer layer comprising a hyperbranched polymer network, wherein the polymer layer has a thickness of from about 100 nm to about 2 pm, wherein the hyperbranched polymer network comprises a hyperbranched polymer, wherein the hyperbranched polymer comprises a poly(aryletherketone) backbone and at least one residue having an end group, and wherein the hyperbranched polymer is crosslinked via the end group.

44. The membrane of claim 43, wherein the polymer layer has a thickness of from about 600 nm to about 800 nm.

45. The membrane of claim 43, wherein the support is an alumina support.

46. The membrane of claim 43, wherein the support consists essentially of a top layer and a bottom layer, wherein the top layer is in-between the polymer layer and the bottom layer, wherein the top layer and the bottom layer differ in one or more of thickness, pore size, and porosity.

47. The membrane of claim 46, wherein the top layer has a thickness of from about 2 pm to about 4 pm, and wherein the bottom layer has a thickness of about 3 mm or less.

48. The membrane of claim 46, wherein the top layer has a thickness of about 3 pm and wherein the bottom layer has a thickness of about 2 mm or less.

49. The membrane of claim 46, wherein the top layer has a pore size of from about 2 nm to about 4 nm and wherein the bottom layer has a pore size of from about 80 nm to about 120 nm.

50. The membrane of claim 46, wherein the top layer has a pore size of about 3 nm and wherein the bottom layer has a pore size of about 100 nm.

51. The membrane of claim 46, wherein the top layer has a porosity of from about 30% to about 50% and wherein the bottom layer has a porosity of from about 20% to about 40%.

52. The membrane of claim 46, wherein the top layer has a porosity of about 40% and wherein the bottom layer has a porosity of about 30%.

53. The membrane of claim 43, wherein the polymer layer has a thickness of about 700 nm.

54. The membrane of claim 43, wherein the poly(aryletherketone) backbone is a polyetherketone (PEK) backbone, a polyetheretherketone (PEEK) backbone, or a polyetherketoneketone (PEKK) backbone.

55. The membrane of claim 43, wherein the hyperbranched polymer comprises repeating units having a structure represented by a formula:

56. The membrane of claim 43, wherein the end group is present in an amount of from about 5 mol% to about 20 mol%.

57. The membrane of claim 43, wherein the end group is present in an amount of about

10 mol%.

58. The membrane of claim 43, wherein the end group is selected from phenylacetylene, ethynyl, propargylether, maleimide, cyanate ester, phthalonitrile, and benzoxazine

59. The membrane of claim 43, wherein the end group is a phenylacetylene end group.

60. The membrane of claim 59, wherein the residue having the phenylacetylene end group has a structure represented by a formula selected from the group consisting of:

61. The membrane of claim 59, wherein the residue having the phenylacetylene end group has a structure represented by a formula:

62. The membrane of claim 43, wherein the membrane is prepared via solution casting.

63. The membrane of claim 43, wherein the membrane is a hollow fiber membrane.

64. The membrane of claim 43, wherein the membrane has a glass transition temperature (T_g) of from about 180 °C to about 300 °C.

65. A method for making the membrane of claim 43, the method comprising the steps of:

(a) providing a composition comprising the hyperbranched polymer network; and

(b) coating the composition onto the support; thereby forming the membrane.

66. A method for separating a first gas species from a second gas species in a gas mixture, wherein the first gas species is different from the second gas species, the method comprising the step of passing the gas mixture through or alongside the membrane of claim 43.

67. The method of claim 66, wherein the membrane has a combination of permeability and selectivity that is about equal to or above Robeson's upper limit.

68. The method of claim 66, wherein the membrane has a selectivity for the first gas species over the second gas species of at least about 4.

69. The method of claim 66, wherein the first gas species and the second gas species are independently selected from the group consisting of CO₂, He, ¾, CH₄, N₂, and O₂.

70. The method of claim 66, wherein the membrane is selective for ¾ over CO2, He,

CH₄, N₂, and/or O₂.

71. The method of claim 66, wherein the membrane is stable at a temperature of about 200 °C or less for fourteen days or less.

72. The method of claim 66, wherein the membrane is stable at a temperature of about 200 °C for at least about fourteen days.