CN117916296A

CN117916296A - Foamable thermoplastic composition, thermoplastic foam and method of making the same

Info

Publication number: CN117916296A
Application number: CN202280060997.2A
Authority: CN
Inventors: H·阿布里瓦亚; E·布罗德里克; A·克鲁格罗夫; K·勒胡塔; 刘天宇; 罗德里戈·洛博; D·麦考维亚克; S·马丁斯; P·尼克尔; M·特里森伯格; 余斌; S·H·马哈茂德; 拉吉夫·辛格; S·希穆拉
Original assignee: Honeywell International Inc
Current assignee: Honeywell International Inc
Priority date: 2021-08-16
Filing date: 2022-08-16
Publication date: 2024-04-19
Also published as: CN117940500A; CN117940499A; CN117916295A

Abstract

The low density thermoplastic foam comprises: (a) A thermoplastic polymer pore comprising pore walls comprising a polyvinyl furan acid ester, wherein at least about 50% by volume of the pores are closed cells; and (b) at least HFO-1224yd contained in the closed cells.

Description

Foamable thermoplastic composition, thermoplastic foam and method of making the same

Cross reference

The present application relates to the following applications, each of which is incorporated by reference: U.S. provisional application 63/233,720 filed 8/16/2021, U.S. provisional application 63/252,110 filed 10/2021, and U.S. provisional application 63/278,497 filed 11/2021.

Technical Field

The present invention relates to foamable thermoplastic compositions, thermoplastic foams, foaming methods, and systems and articles made therefrom.

Background

While foams are used in a variety of applications, developing foams that have excellent performance characteristics and are cost effective to produce is a desirable but difficult goal. While achieving this goal while developing environmentally friendly foam is more difficult. Producing environmentally friendly foams is particularly difficult because they contain both a blowing agent component and a resin component that forms the foam structure, and each of these components has an impact on foam performance and environmental characteristics. Environmental considerations include not only the recyclability and sustainability of the polymeric resin forming the foam structure, but also the low environmental impact of the blowing agent used to form the foam, such as Global Warming Potential (GWP) and Ozone Depletion Potential (ODP) of the blowing agent. Thus, it is a significant challenge to develop foams that have excellent properties while being producible in a cost-effective manner from environmentally friendly blowing agents and environmentally friendly resins.

From the standpoint of recyclability and/or sustainable sources, the potential advantages of foams based on certain thermoplastic resins (including polyester resins) have been investigated. However, some difficulties are encountered in developing such materials. For example, it has been a challenge to develop polyester resins that are truly recyclable, producible from sustainable sources, and compatible with blowing agents that in combination with thermoplastic materials are capable of producing foams with good performance characteristics. In many applications, performance characteristics that are considered highly desirable include the production of high quality closed cell foams that are low density (and thus light weight when in use) and that have relatively high mechanical integrity and strength at the same time.

Regarding the selection of thermoplastic resins, EP 3,231,836 acknowledges that despite the interest in thermoplastic resins, in particular polyester-based resins, this interest has encountered difficulties in development, including difficulty in determining the proper foaming grade of such resins. Furthermore, while EP 3,231,836 notes that certain polyethylene terephthalate (PET) resins (including recycled forms of PET) can be melt extruded with suitable physical and/or chemical blowing agents to produce closed cell foams having the potential for low density and good mechanical properties, there is no disclosure that any such resin can produce foams having both good environmental properties and good performance properties, and can also be formed from sustainable sources. The' 836 application identifies several possible polyester resins for forming open cell foams, including polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, polyethylene naphthalate, polyethylene furanoate, or mixtures of two or more of these. While the use of polyester materials to produce a foam that is substantially free of closed cells may be beneficial for some applications, as required by EP'836, a disadvantage of such structures is that, in general, open cell foams will exhibit relatively poor mechanical strength characteristics.

While plastics based on 2, 5-furandicarboxylic acid based polyesters have been noted to have some potential advantages in certain applications, such as good gas barrier properties, it has also been recognized that there are some substantial problems with the formation of foam materials from such plastics materials. For example, CN108410000 teaches that 2, 5-furandicarboxylic acid based polyesters have very poor foaming properties and extremely unfavorable processing conditions. These problems are said to be solved by using a glassy (i.e., amorphous) polymer sheet, which is then exposed to a special, relatively complex and cumbersome twin blowing agent process.

The method described in CN108410000 has several drawbacks, including the need for undesirably long processing times to produce specialized, treated preforms and the use of relatively complex dual blowing agent processes. This method is also very disadvantageous because it is not readily adaptable to commercial extrusion equipment currently in use, and therefore requires an undesirably high new capital cost in implementation.

CN 108484959 also recognizes that polyesters based on 2, 5-furandicarboxylic acid (such as PEF) are poor in foamability and attempts to solve this substantial problem by blending ethylene 2, 5-furandicarboxylic acid with polyfunctional monomers selected from alcohols, esters, alkanes, carboxylic acids and anhydrides to form high melt viscosity polymers. The foaming properties of the material are said to be improved relative to PEF, but no information is provided about the foaming process.

US2020/0308363 and US2020/0308396 each disclose the production of an amorphous polyester copolymer comprising starting with recycled polyester (of which PET is the only example) as the main component, followed by a series of processing steps to obtain an amorphous copolymer, i.e. a copolymer without crystallinity. These publications indicate that it is not possible to easily form low density polyester foams from crystalline or semi-crystalline polymers, and that this problem can be solved by forming amorphous copolyester polymeric materials and using such amorphous materials to form foams. The synthesis of poly (ethylene furanoate) (PEF) using ethylene glycol and 2, 5-furandicarboxylic acid is mentioned, but not illustrated. The substantially amorphous (i.e., no crystallinity according to 0J/gΔh prior to foaming) terpolymer formed from PET, polypropylene furanate, and polycarbonate is said to have been foamed using CO2 as a blowing agent. Foam properties are not disclosed. A number of different classes of blowing agents are mentioned, including CO2, HFO-1233zd, cyclopentane, acetone, and methanol, commonly used with amorphous polymers.

US 9790342 discloses foams formed from polyphenol tannins, which can be combined with a large number of possible monomers and in the list of monomers are 2, 5-furandicarboxylic acid. These foams are said to be partially open and partially closed, with an open cell content of less than 50%. A number of potential blowing agents are disclosed, including the haloolefin HFO-1336mmz.

Regarding blowing agents, generally halogenated olefin blowing agents, including Hydrofluoroolefins (HFOs) and hydrochlorofluoroolefins (hcfcos), are known for use in several specific thermoplastic foams, as disclosed, for example, in US 2009/0305876, assigned to the assignee of the present invention and incorporated herein by reference. Although the' 876 application discloses the use of HFO and HFCO blowing agents with various thermoplastic materials, including PET, for forming foam, there is no disclosure or suggestion that any such blowing agent be used with any other type of polyester resin.

The applicant has overcome the problem of forming a high performance foam that also has advantageous environmental characteristics (i.e. high sustainability and low atmospheric impact) and in so doing has realized that these problems can be overcome and one or more unexpected advantages can be achieved by forming a thermoplastic foam, in particular an extruded thermoplastic foam, using a polyester resin as disclosed herein in combination with a blowing agent comprising one or more hydrohaloolefins as disclosed herein.

Disclosure of Invention

As mentioned above, there is a continuing need for sustainable and environmentally friendly polymeric materials, particularly polymeric foams, while there is a continuing need for such polymeric foams that are capable of providing both low density and high strength. Such a combination of characteristics is particularly important in many applications that require a foam having a low weight (i.e., having a low density) at a given volume, but that also require strength in use. One example of such use relates to the construction of wind turbine blades, where both light weight and high strength are important, and where sustainability and environmental friendliness are also important in such applications. As mentioned above, for example, previous efforts to address this need have encountered numerous technical problems and drawbacks, and no fully acceptable solution has been found so far.

The present invention meets one or more of the above-identified needs and overcomes the prior art problems and includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising cell walls comprising a polyvinyl furoate having a crystallinity of at least 15%, wherein at least 25% of the cells are closed cells; and

(B) 1224yd contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 1A1.

(B) 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 1A2.

(B) 1224yd (E) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 1A3.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising a cell wall comprising a polyvinyl furoate having a crystallinity of at least 15%, wherein at least 25% by volume of the cell is closed cell, and wherein the ethylene furoate fraction is at least 85% by weight of the thermoplastic polymer; and

(B) 1224yd contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 1B1.

The present invention includes a low density thermoplastic foam comprising:

(B) 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 1B2.

The present invention includes a low density thermoplastic foam comprising:

(B) 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 1B3.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising a cell wall comprising a polyvinyl furoate having a crystallinity of at least 15%, wherein at least 15% by volume of the cell is closed cell, and wherein the polyvinyl furoate fraction is at least 85% by weight of the thermoplastic polymer; and

(B) A gas in the closed cells, the gas comprising 1224yd, preferably 1224yd (Z).

For convenience, the foam according to this paragraph is referred to herein as foam 1C.

The present invention includes a low density thermoplastic foam comprising:

(B) A gas in the closed cells, the gas comprising at least about 25% by weight 1224yd, preferably 1224yd (Z).

For convenience, the foam according to this paragraph is referred to herein as foam 1D.

The present invention includes a low density thermoplastic foam comprising:

(B) A gas in the closed cells, the gas comprising at least about 50% by weight 1224yd, preferably 1224yd (Z).

For convenience, the foam according to this paragraph is referred to herein as foam 1E.

Reference will be made to a numbered foam (e.g., foam 1) or a numbered foam group as defined herein at various locations herein, and such reference will refer to each of such numbering systems, including each system having a numbering within the group, including any suffix numbering system. For example, reference to foam 1 includes reference to each of foams 1A, 1B, 1C, 1D, and 1E individually, and reference to foams 1 through 2 should be understood to include reference to each of foams 1A, 1B, 1C, 1D, 1E, 2A, 2B, 2C, 2D, 2E, and 2F individually. In addition, this convention is used throughout this specification for other defined materials, including blowing agents.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising pore walls comprising a polyvinyl furan acid ester, wherein at least 25% of said pores are closed cells; and

(B) 1224yd, preferably 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 2A.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising pore walls comprising a polyvinyl furanoate having a crystallinity of at least 15%, wherein at least 25% of the pores are closed cells, and wherein the thermoplastic polymer does not comprise a tannin fraction or comprises a tannin fraction in an amount of less than 20 weight%; and

(B) 1224yd, preferably 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 2B.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising cell walls comprising a polyvinyl furoate having a crystallinity of at least 35%, wherein at least 50% of the cells are closed cells; and

(B) A gas in the closed cells, wherein the gas comprises 1224yd.

For convenience, the foam according to this paragraph is referred to herein as foam 2C.

The present invention includes a low density thermoplastic foam comprising:

(B) A gas in the closed cells, wherein the gas comprises about 25wt% to 100 wt% 1224yd, preferably 1224yd (Z). For convenience, the foam according to this paragraph is referred to herein as foam 2D.

The present invention includes a low density thermoplastic foam comprising:

(B) A gas in the closed cells, wherein the gas comprises 1224yd (preferably 1224yd (Z)) and at least one co-blowing agent. For convenience, the foam according to this paragraph is referred to herein as foam 2E.

The present invention includes a low density thermoplastic foam comprising:

(B) A gas in the closed cells, wherein the gas consists essentially of 1224yd, preferably 1224yd (Z). For convenience, the foam according to this paragraph is referred to herein as foam 2F.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising a cell wall comprising a polyvinyl furoate having a crystallinity of at least 15%, wherein at least about 50% by volume of the cell is closed cell, and wherein the polyvinyl furoate fraction is at least 85% by weight of the thermoplastic polymer; and

(B) 1224yd, preferably 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 3A.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising cell walls comprising a polyvinyl furoate having a crystallinity of at least 15% and a molecular weight of from about 25,000 to about 170,000, wherein at least about 25% by volume of the cells are closed cells; and

(B) One or more HFOs having three or four carbon atoms and/or one or more HFCO having three or four carbon atoms contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 3B.

The present invention includes a low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising cell walls comprising a polyvinyl furoate having a crystallinity of at least 15% and a molecular weight of from about 80,000 to about 170,000, wherein at least about 25% by volume of the cells are closed cells; and

(B) 1224yd, preferably 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 3C.

The present invention includes a low density thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls comprising a polyvinyl furoate having a crystallinity of at least 25% and a molecular weight of from about 80,000 to about 170,000, wherein at least about 35% to about 90% by volume of the pores are closed cells; and

(B) 1224yd, preferably 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 3D.

The present invention includes a low density thermoplastic foam comprising:

(a) Thermoplastic polymer cells comprising cell walls comprising a polyvinyl furan acid ester having a crystallinity of from about 35% to about 65% and a molecular weight of from about 80,000 to about 170,000, wherein at least about 35% to about 90% by volume of the cells are closed cells; and

(B) 1224yd, preferably 1224yd (Z) contained in the closed cells.

For convenience, the foam according to this paragraph is referred to herein as foam 3E.

The present invention includes a low density closed cell thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls comprising a polyvinyl furan acid ester; and

(B) A blowing agent comprising 1224yd, preferably 1224yd (Z), contained in the closed cells, wherein the foam has a Relative Foam Density (RFD) of about 0.1 or less and a foam density of less than 0.3 g/cc. For convenience, the foam according to this paragraph is referred to herein as foam 4A.

(a) Thermoplastic closed cells comprising cell walls consisting essentially of a polyvinyl furanate that has been treated with a chain extender; and

(B) A blowing agent comprising 1224yd, preferably 1224yd (Z), contained in the closed cells, wherein the foam has an RFD of about 0.1 or less and a density of less than 0.3 g/cc. For convenience, the foam according to this paragraph is referred to herein as foam 4B.

(a) A thermoplastic polymer pore comprising pore walls forming closed cells, wherein the thermoplastic material comprises a polyvinyl furanate-based polymer having a crystallinity of at least about 15% and a molecular weight greater than 25,000; and

(B) A blowing agent contained in the closed cells, the blowing agent comprising 1224yd, preferably 1224yd (Z). For convenience, the foam according to this paragraph is referred to herein as foam 5A.

(a) A thermoplastic polymer pore comprising pore walls forming closed cells, wherein the thermoplastic material comprises a polyvinyl furanoate-based polymer having a crystallinity of at least about 25% and a molecular weight of from about 25,000 to about 170,000; and

(B) A blowing agent contained in the closed cells, the blowing agent comprising 1224yd. For convenience, the foam according to this paragraph is referred to herein as foam 5B.

(a) Thermoplastic closed cells comprising cell walls consisting essentially of a polyvinyl furan acid ester; and

(B) 1224yd contained in the closed cells,

Wherein the foam has a density of less than 0.3 g/cc. For convenience, the foam according to this paragraph is referred to herein as foam 6A.

The present invention includes a closed cell thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls consisting essentially of polyvinyl furanoate, wherein at least about 50% by volume of the cells are closed cells; and

(B) 1224yd contained in the closed cells. For convenience, the foam according to this paragraph is referred to herein as foam 6B.

The present invention includes a closed cell thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls consisting essentially of polyvinyl furanoate, wherein at least about 75% by volume of the cells are closed cells; and

(B) 1224yd contained in the closed cells. For convenience, the foam according to this paragraph is referred to herein as foam 6C.

The present invention includes a closed cell thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls consisting essentially of polyvinyl furanoate, wherein at least about 90% by volume of the cells are closed cells; and

(B) 1224yd contained in the closed cells. For convenience, the foam according to this paragraph is referred to herein as foam 6D.

The invention also provides foamable compositions, foaming methods, and additional foams as described below.

Drawings

FIG. 1 is a schematic diagram of an extrusion system and method according to one embodiment of the present invention and according to the examples herein.

Definition of the definition

1234Ze refers to 1, 3-tetrafluoropropene and there is no limitation on the isomeric forms.

Trans 1234ze and 1234ze (E) each refer to trans 1, 3-tetrafluoropropene.

Cis 1234ze and 1234ze (E) each refer to cis 1, 3-tetrafluoropropene.

1234Yf refers to 2, 3-tetrafluoropropene.

1233Zd refers to 1-chloro-3, 3-trifluoropropene, and there is no limitation on the isomeric forms.

Trans 1233zd and 1233zd (E) each refer to trans 1-chloro-3, 3-trifluoropropene.

1224Yd refers to 1-chloro-2, 3-tetrafluoropropane and there is no limitation on the isomeric forms.

Cis 1224yd and 1224yd (Z) refer to cis 1-chloro-2, 3-tetrafluoropropane.

Trans 1224yd and 1224yd (E) refer to trans 1-chloro-2, 3-tetrafluoropropane.

1336Mzz refers to 1, 4-hexafluorobutene, with no limitation on the isomeric forms.

Trans 1336mzz and 1336mzz (E) refer to trans 1, 4-hexafluorobutene, respectively.

Cis 1336mzz and 1336mzz (Z) refer to cis 1, 4-hexafluorobutene, respectively.

Closed cell foam means that a substantial percentage of the cells by volume in the foam are closed, for example, about 20% by volume or more.

Crystallinity refers to the crystallinity of a polymer as measured by Differential Scanning Calorimetry (DSC) according to ASTM D3418 and ASTM E1356.

The ethylene furanoate moiety refers to the following structure:

FDCA refers to 2, 5-furandicarboxylic acid and has the following structure:

FDME refers to dimethyl 2, 5-furandicarboxylate and has the following structure:

MEG refers to monoethylene glycol and has the following structure:

As used herein, moieties refer to different repeating units in a polymer. For clarity, a copolymer having two repeating units A and B present in a 1:1 ratio will have 50 mole% of the A moiety and 50 mole% of the B moiety.

Other moieties as used herein refer to moieties that are not ethylene furanates and are not formed from tannins.

Methylal refers to dimethoxymethane ((CH 3O) 2CH 2).

PEF homopolymer refers to a polymer consisting of ethylene furanoate moieties. For the avoidance of doubt, PEF homopolymers may comprise materials that may be present at impurity levels.

PEF copolymer refers to a copolymer having at least 50 wt% of ethylene furanate moieties and an amount of moieties other than ethylene furanate moieties.

PEF refers to poly (ethylene furanoate) and covers and is intended to reflect the description of PEF homopolymers and PEF copolymers.

SSP refers to solid state polymerization.

PMDA refers to pyromellitic dianhydride having the structure:

As used herein, a tannin moiety refers to a polymer repeat unit corresponding to a tannin used to form a polymer, including those as disclosed in U.S. patent No. 9,890,342.

Detailed Description

Poly (ethylene furan acid ester)

The present invention relates to foams and foam articles comprising cell walls comprising PEF.

The PEF forming the cell walls of the foams and foam articles of the present invention may be PEF homopolymers or PEF copolymers.

PEF homopolymer is a known material, which is known to be formed by: (a) esterification and polycondensation of FDCA with MEG; or (b) transesterification and polycondensation of FDME with MEG, for example as follows:

A detailed description of such known esterification and polycondensation synthesis processes is provided in GB patent 621971 (Drewitt, j.g.n. and Lincocoln, j., "entitled" improvement of polymer (Improvements in Polymers) ") incorporated herein by reference. A detailed description of such known transesterification and polycondensation synthetic methods is provided in Gandini, a., SILVESTRE, a.j.d., neto, c.p., sousa, a.f., and Gomes, m. (2009), "furan counterparts of polyethylene terephthalate: renewable resource based alternative materials (The furan counterpart of poly(ethylene terephthalate):an alternative material based on renewable resources.)", journal of polymer science: polymer chemistry (J.Polym.Sci.Polym.chem.) 47,295-298.Doi:10.1002/pola.23130, which is incorporated herein by reference.

Foam

The foam of the present invention is formed from PEF homopolymers, PEF copolymers, or combinations/mixtures thereof.

In preferred embodiments, the foam may be formed from PEF homopolymers, wherein the polymer has at least 99.5 wt% or at least 99.9 wt% ethylene furanate moieties.

In preferred embodiments, it is contemplated that foam may be formed from PEF copolymers, wherein the polymer (including PEF copolymers) has from about 60 wt% to about 99 wt% of ethylene furanoate moieties, or from about 70 wt% to about 99 wt% of ethylene furanoate moieties, or from about 85 wt% to about 99 wt% of ethylene furanoate moieties, or from about 90 wt% to about 99 wt% of ethylene furanoate moieties, or from about 95 wt% to about 99.5 wt% of ethylene furanoate moieties. The invention also includes a foam formed from PEF having less than 20 wt.% tannin fraction, or less than 15 wt.% tannin fraction, or less than 10 wt.% tannin fraction, or less than 5 wt.% tannin fraction, or substantially no tannin fraction.

For those embodiments of the invention involving PEF copolymers, it is contemplated that those skilled in the art, in view of the teachings contained herein, will be able to select the type and amount of copolymer material to be used within each of the ranges described herein to achieve the desired reinforcement/modification of the polymer without undue experimentation.

For those embodiments of the invention that involve the use of PEF homopolymers or PEF copolymers, it is contemplated that such materials can be formed having a variety of molecular weights and physical properties within the scope of the present invention. In a preferred embodiment, the foam (including each of foams 1-6) is formed from PEF having the characteristic ranges determined in table 1 below, these characteristic ranges being measured as described in the examples herein:

TABLE 1

	Wide range of	Intermediate range	Narrow range
				Polymer characteristics
Molecular weight	25,000-150,000	45,000-130,000	55,000-120,000
				Glass transition temperature, T _g, DEG C	75-100	75-95	75-95
Melting temperature, T _m, DEG C	180-250	190-240	200-230
				Decomposition temperature, T _d, DEG C	300-420	320-400	330-380
Crystallinity, percent	25-75	30-60	40-50

In general, given the teachings contained herein, it is expected that one of ordinary skill in the art will be able to formulate PEF polymers within the above-described characteristics without undue experimentation. However, in a preferred embodiment, one or more of the above synthetic methods are used, in combination with a variety of known complementary processing techniques, including by treatment with a chain extender such as PMDA and/or SSP processing, to obtain a general PEF homopolymer, particularly a PEF homopolymer, having these characteristics. It is believed that one skilled in the art, given the disclosure contained herein, including the polymer synthesis described in the examples below, will be able to prepare PEF polymers within the characteristics ranges set forth in the tables above and elsewhere herein.

Examples of chain extension treatment methods for polyesters are provided in the article "polyethylene terephthalate chain extension by reactive extrusion method for 16 days at (Recycled poly(ethylene terephthalate)chain extension by a reactive extrusion process)",Firas Awaja,Fugen Daver,Edward Kosior,2004, available at https:// doi.org/10.1002/pen.20155, incorporated herein by reference. As explained in US1009/0264545, which is incorporated herein by reference, chain extenders are generally at least difunctional compounds with respect to reactive groups that can react with end groups or functional groups in the polyester to extend the length of the polymer chain. In some cases, such treatments may advantageously increase the average molecular weight of the polyester to improve its melt strength and/or other important characteristics, as disclosed herein. The degree of chain extension achieved is at least partially dependent on the structure and functionality of the compound used. A variety of compounds are useful as chain extenders. Non-limiting examples of chain extenders include trimellitic anhydride, pyromellitic dianhydride (PMDA), trimellitic acid, haloformyl derivatives thereof, or compounds containing multifunctional epoxy (e.g., glycidyl) or oxazoline functional groups. Nanocomposites such as finely divided nanoclays may optionally be used to control viscosity. Commercial chain extenders include CESA-extension from Clariant, joncryl from Basf, or Lotader from Arkema. The amount of chain extender may vary depending on the type and molecular weight of the polyester component. The amount of chain extender used to treat the polymer can vary widely and in preferred embodiments is in the range of about 0.1 wt% to about 5 wt%, or preferably about 0.1 wt% to about 1.5 wt%. Examples of chain extenders are also described in U.S. patent No. 4,219,527, incorporated herein by reference.

An example of an SSP processing method for poly (vinylfuranate) is provided in the article "solid state polymeric biobased polyester of poly (vinylfuranate I: influence of catalyst type on molecular weight increase (Solid-State Polymerization of Poly(ethylene furanoate)Biobased Polyester,I:Effect of Catalyst Type on Molecular Weight Increase)",Nejib Kasmi,Mustapha Majdoub,George Z.Papageorgiou,Dimitris S.Achilias and Dimitrios n.bikiaris, incorporated herein by reference.

PEF thermoplastic polymers particularly useful in preparing the foamable compositions and foams of the invention are listed in the following thermoplastic polymer table (table 2), wherein all values in the table are understood to be preceded by the word "about".

TABLE 2 thermoplastic Polymer Table

/>

For the purpose of defining the terminology used herein, it should be noted that at various locations herein reference will be made to the thermoplastic polymers shown in the first column in each row in the above TPP table, and that reference to each of these numbers is to reference to the thermoplastic polymer as defined in the corresponding column of that row. References to a set of TPPs defined in the above table by reference to a TPP number refer to each such numbered TPP, both individually and independently, including each TPP having the indicated number, including any such number having a suffix. Thus, for example, reference to TPP1 is a separate and independent reference to TPP1A, TPP1B, TPP1C, TPP D and TPP1E. References to TPP1-TPP2 are separate and independent references to TPP1A, TPP1B, TPP1C, TPP1D, TTP1E, TPP2A, TPP2B, TPP2C, TPP1D and TTP1E. This usage convention is also used for the following foamable composition table and foam table.

Foaming agent

As explained in detail herein, the present invention includes, but is not limited to, applicants' discovery that a select set of blowing agents is capable of providing foamable PEF foamable compositions and PEF foams having a difficult to achieve and surprising combination of physical properties, including low density and good mechanical strength properties.

The blowing agent used according to the invention preferably comprises one or more hydrohaloolefins having three or four carbon atoms. For convenience, the blowing agent according to this paragraph is sometimes referred to herein as blowing agent 1.

The blowing agent used in accordance with the present invention preferably comprises one or more of 1234ze, 1234yf, 1336mzz (Z), 1336mzz (E), 1233zd and 1224yd (hereinafter blowing agent 2 for convenience); or one or more of trans 1234ze, 1336mzz (Z), 1336mzz (E), trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 3 for convenience); or one or more of trans 1234ze, 1336mzz (Z), 1336mzz (E), trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 4 for convenience); or one or more of trans 1234ze and 1224yd (hereinafter referred to as blowing agent 5 for convenience); or 1224yd (Z) (hereinafter referred to as blowing agent 6 for convenience); or 1234yf (hereinafter referred to as blowing agent 7 for convenience); or 1224yd (hereinafter referred to as blowing agent 8 for convenience); or comprises trans 1233zd (hereinafter referred to as blowing agent 9 for convenience).

It is therefore contemplated that the blowing agents of the present invention (including each of blowing agents 1 through 9) may include a co-blowing agent in addition to each of the blowing agents described above, the co-blowing agent being included in one or more optional latent co-blowing agents as described below. In a preferred embodiment, the foamable composition, foam and foaming method of the invention comprise a blowing agent as described herein, wherein the blowing agent (comprising the compound or group of compounds specifically shown in each of blowing agents 1 to 9) is present in an amount of at least about 50 wt%, or preferably at least about 60 wt%, preferably at least about 70 wt%, or preferably at least about 80 wt%, or preferably at least about 90 wt%, or preferably at least about 95 wt%, or preferably at least about 99 wt%, based on the total weight of all blowing agent components.

The blowing agent used in accordance with the present invention also preferably consists essentially of one or more of 1234ze, 1234yf, 1336mzz (Z), 1233zd and 1224yd (hereinafter referred to as blowing agent 10 for convenience); or consist essentially of one or more of trans 1234ze, 1336mzz (Z), trans 1233zd, and cis 1224yd (hereinafter referred to as blowing agent 11 for convenience); or consist essentially of one or more of trans 1234ze, 1336mzz (Z), trans 1233zd, and cis 1224yd (hereinafter referred to as blowing agent 12 for convenience); or consist essentially of one or more of trans 1234ze and 1224yd (hereinafter referred to as blowing agent 13 for convenience); or consist essentially of trans 1234ze (hereinafter blowing agent 14 for convenience); or consists essentially of 1336mzz (Z) (hereinafter referred to as blowing agent 15 for convenience); or consists essentially of 1336mzz (E) (hereinafter blowing agent 16 for convenience); or consist essentially of 1234yf (hereinafter referred to as blowing agent 17 for convenience); or consist essentially of 1224yd (hereinafter blowing agent 18 for convenience); or consist essentially of trans 1233zd (hereinafter referred to as blowing agent 19 for convenience).

It is contemplated and understood that the blowing agents of the present invention (including each of blowing agents 1 through 19) may include one or more co-blowing agents not included in the illustrated selections, provided that the amount of such co-blowing agents does not interfere with or eliminate the ability to obtain relatively low density foams (including each of foams 1 through 6) as described herein, and preferably also does not interfere with or eliminate the ability to obtain foams having mechanical strength characteristics as described herein. Thus, given the teachings contained herein, it is contemplated that one of ordinary skill in the art will be able to select, for example, one or more of the following potential co-blowing agents for a particular application without undue experimentation: one or more saturated hydrocarbons or Hydrofluorocarbons (HFCs), particularly C4-C6 hydrocarbons or C1-C4 HFCs, as known in the art. Examples of such HFC co-blowing agents include, but are not limited to, difluoromethane (HFC-32), fluoroethane (HFC-161), difluoroethane (HFC-152), trifluoroethane (HFC-143), tetrafluoroethane (HFC-134), pentafluoroethane (HFC-125), pentafluoropropane (HFC-245), hexafluoropropane (HFC-236), heptafluoropropane (HFC-227 ea), pentafluorobutane (HFC-365), hexafluorobutane (HFC-356), and one or a combination of all of the isomers of all such HFCs. Regarding hydrocarbons, in certain preferred embodiments, the blowing agent compositions of the present invention may also include, for example, isopentane, n-pentane, and/or cyclopentane, and butane and/or isobutane. Other materials may also be included such as water, CO2, CFCs such as trichlorofluoromethane (CFC-11) and dichlorodifluoromethane (CFC-12), hydrochlorocarbons such as HCC, such as ethylene dichloride (preferably trans-ethylene dichloride), ethyl chloride and chloropropane, HCFCs, C1-C5 alcohols such as ethanol and/or propanol and/or butanol, C1-C4 aldehydes, C1-C4 ketones, C1-C4 ethers including ethers such as dimethyl ether and diethyl ether, diethers such as dimethoxymethane and diethoxymethane, and methyl formate, organic acids such as but not limited to formic acid, including combinations of any of these, but such components are not necessarily preferred in many embodiments due to negative impact on environmental impact.

The blowing agent used in accordance with the present invention also preferably consists of one or more of 1234ze, 1234yf, 1336mzz (Z), 1233zd and 1224yd (hereinafter referred to as blowing agent 20 for convenience); or one or more of trans 1234ze, 1336mzz (Z), trans 1233zd, and cis 1224yd (hereinafter referred to as blowing agent 21 for convenience); or one or more of trans 1234ze, trans1336mzz (Z), trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 22 for convenience); or one or more of trans 1234ze and 1224yd (hereinafter referred to as blowing agent 23 for convenience); or 1224yd (Z) (hereinafter referred to as blowing agent 24 for convenience); or t1224yd (E) (hereinafter referred to as blowing agent 25 for convenience).

Foam and foaming method

The foams of the present invention may generally be formed from the foamable compositions of the present invention. In general, the foamable composition of the invention may be formed by combining PEF polymer with the blowing agent of the invention (including each of blowing agents 1 through 25).

Foamable compositions included within the present invention and providing particular advantages in connection with forming the foam of the present invention are described in the following foamable composition table (table 3), wherein all values in the table are understood to be preceded by the word "about", and wherein the following terms used in the table have the following meanings:

CBAG1 refers to a co-blowing agent selected from the group consisting of: 1234ze (E), 1336mzz (Z), 1233zd (E), 1234yf, and combinations of two or more of these.

CBAG2 refers to a co-blowing agent selected from the group consisting of: water, CO2, C1-C6 Hydrocarbons (HC) HCFCs, C1-C5 HFCs, C2-C4 hydrohaloolefins, C1-C5 alcohols, C1-C4 aldehydes, C1-C4 ketones, C1-C4 ethers, C1-C4 esters, organic acids, and combinations of two or more of these.

CCBAG3 refers to a co-blowing agent selected from the group consisting of: water, CO2, isobutane, n-butane, isopentane, cyclopentane, cyclohexane, trans-dichloroethylene, ethanol, propanol, butanol, acetone, dimethyl ether, diethyl ether, dimethoxymethane, diethoxymethane, methyl formate, difluoromethane (HFC-32), fluoroethane (HFC-161), 1-difluoroethane (HFC-152 a), trifluoroethane (HFC-143), 1112-tetrafluoroethane (HFC-134 a), pentafluoroethane (HFC-125), pentafluoropropane (HFC-245), hexafluoropropane (HFC-236), heptafluoropropane (HFC-227 ea), pentafluorobutane (HFC-365), hexafluorobutane (HFC-356), and combinations of any two or more of these.

NR means not required.

TABLE 3 foamable composition table

/>

Foam forming method

In view of the disclosure contained herein, any one or more of a variety of known techniques for forming thermoplastic foams may be used to form the foams of the present invention, including each of foams 1-6 and each of foams F1-F6, as well as all such techniques and all foams formed thereby or within the broad scope of the present invention. For clarity, it should be noted that the definition of Foam in the following table all starts with the letter F only, in contrast to Foam which starts with the capitalized word Foam as defined in the paragraph in the summary of the invention above.

Generally, the forming step involves first introducing the inventive blowing agent including each of blowing agents 1 through 31 into the inventive PEF polymer including each of TPP1 through TPP6 to form a foamable PEF composition comprising PEF and blowing agent. One example of a preferred method of forming the foamable PEF composition of the invention is plasticizing the PEF, preferably comprising heating the PEF to, preferably above, its melting temperature, and then exposing the PEF melt to a blowing agent under conditions effective to incorporate (preferably by dissolution) the desired amount of blowing agent into the polymer melt.

In a preferred embodiment, the foaming method of the present invention comprises providing a foamable composition of the present invention comprising each of FC1 to FC6 and foaming the provided foamable composition. In a preferred embodiment, the foaming process of the present invention comprises providing a foamable composition of the present invention comprising each of FC1 to FC6 and extruding the provided foamable composition to form a foam of the present invention comprising each of foams 1 to 6 and each of foams F1 to F6.

The foaming process of the present invention may include batch, semi-batch, continuous processes, and combinations of two or more of these processes. Batch processes generally involve preparing at least a portion of the foamable polymer composition in a storable state, including each of FC1 to FC6, and then using that portion of foamable polymer composition to prepare a foam at some future point in time. The semi-batch process involves preparing at least a portion of a foamable polymer composition comprising each of FC1 to FC6, and intermittently expanding the foamable polymer composition into a foam comprising each of foams 1 to 6 and each of foams F1 to F6, all in a single process. For example, U.S. Pat. No. 4,323,528, which is incorporated herein by reference, discloses a method for preparing thermoplastic foam by a cumulative extrusion process. Accordingly, the present invention includes a method comprising: 1) Mixing a PEF thermoplastic polymer comprising each of TPP1 to TPP6 with a blowing agent of the present invention comprising each of blowing agents 1 to 31 under conditions to form a foamable PEF composition; 2) Extruding a foamable PEF composition comprising each of FC1 to FC6 into a holding zone maintained at a temperature and pressure that does not allow the foamable composition to foam, wherein the holding zone preferably comprises a die defining an orifice to a low pressure zone at which the foamable polymer composition comprising each of FC1 to FC6 foams, the holding zone further comprising an openable door that closes the orifice of the die; 3) Periodically opening the door while applying mechanical pressure to the foamable polymer composition comprising each of FC1 to FC6 through the movable ram to expel it from the holding zone through the die orifice into the low pressure zone, and 4) expanding the expelled foamable polymer composition under the influence of the blowing agent to form a foam comprising each of foams 1 to 6 and each of foams F1 to F6.

The invention may also be used with a continuous process to form foam. For example, such continuous processes involve forming a foamable PEF composition, including each of FC1 to FC6, and then expanding the foamable PEF composition without substantial interruption. For example, a foamable PEF composition comprising each of FC1 to FC6 can be prepared in an extruder as follows: heating a selected PEF polymer resin (including each of TPP1 through TPP 6) to form a PEF melt, incorporating a blowing agent of the present invention (including each of blowing agents 1 through 31) into the PEF melt, preferably by dissolving the blowing agent into the PEF melt at an initial pressure, to form a foamable PEF composition comprising a combination of substantially uniform PEF and blowing agent (including each of FC1 through FC 6), and then extruding the foamable PEF composition into a zone through a die at a selected blowing pressure, and allowing the foamable PEF composition to expand into a foam under the influence of the blowing agent, including each of foams 1 through 6 and each of foams F1 through F6 described below. Optionally, the foamable PEF composition comprising PEF polymer (including each of FC1 to FC 6) and incorporated blowing agent (including each of blowing agents 1 to 31) may be cooled prior to extruding the composition through a die to enhance certain desired characteristics of the resulting foam (including each of foams 1 to 6 and each of foams F1 to F6).

The process may be carried out, for example, using extrusion equipment of the general type disclosed in fig. 1. In particular, the extrusion apparatus may include a raw material feed hopper 10 for containing the PEF polymer 15 of the present invention (including each of TPP1 to TPP 6) and one or more optional components (which may be added with the PEF in the hopper or optionally elsewhere in the process, depending on the specific needs of the user). The feed 15, in addition to the blowing agent, may be charged into a hopper and delivered to the screw extruder 10. Extruder 20 may include thermocouples (not shown) at three points along its length and a pressure sensor (not shown) at the discharge end 20A of the extruder. The mixer portion 30 may be located at the discharge end 20A of the extruder for receiving the blowing agent components of the present invention (including each of blowing agents 1-31) via one or more metering pumps 40A and 40B and mixing those blowing agents into the PEF melt in the mixer portion. Sensors (not shown) may be included for monitoring the temperature and pressure of the mixer portion 30. Mixer portion 30 may then discharge the foamable composition melt of the invention (including each of FC1 to FC 6) into a pair of melt coolers 50 oriented in series, with a temperature sensor (not shown) located in each cooler to monitor the melt temperature. The melt is then extruded through a die 60 which also has temperature and pressure sensors (not shown) for monitoring the temperature and pressure at the die. The die pressure and temperature may vary depending on the needs of each particular extrusion application for which the foam 70 of the present invention is produced, including each of foams 1-6 (defined above) and each of foams F1-F6 (defined below), as described below. The foam may then be carried away from the extrusion apparatus by conveyor 80.

The foamable polymer composition of the invention (including each of FC1 to FC 6) may optionally contain additional additives such as nucleating agents, pore control agents, glass fibers and carbon fibers, dyes, pigments, fillers, antioxidants, extrusion aids, stabilizers, antistatic agents, flame retardants, IR attenuators, and thermal insulation additives. Nucleating agents include, inter alia, materials such as talc, calcium carbonate, sodium benzoate, chemical blowing agents such as azodicarbonamide or sodium bicarbonate and citric acid. IR attenuators and thermally insulating additives may include carbon black, graphite, silica, metal flakes or powders, and the like. Flame retardants may include brominated materials such as hexabromocyclodecane and polybrominated diphenyl ethers, among others. Each of the additional optional additives described above may be introduced into the foam at different times and locations in the process, according to known techniques, and all such additives and methods of addition are within the broad scope of the present invention.

Foam

In a preferred embodiment, the foam of the present invention is formed in a commercial extrusion apparatus and has the characteristics shown in table 4 below, wherein the values are measured as described in the examples herein:

TABLE 4 Table 4

Foams that are included in the present invention and that provide particular advantages are described in table 5 below, and wherein all values in the table are understood to be preceded by the word "about", and wherein the designation NR means "not required".

TABLE 5 foam Table

/>

The foams of the present invention have a wide range of uses. The foams of the present invention (including each of foams 1-6 and foams F1-F6) have unexpected advantages in applications where low density and/or good compression and/or tensile and/or shear properties, and/or long term stability, and/or sustainable sources, and/or being made of recycled materials and being recyclable are required. In particular, the foams of the present invention (including each of foams 1 to 6 and each of foams F1 to F6) have unexpected advantages in the following applications: wind energy applications (wind turbine blades (shear webs, shells, cores and nacelle), marine applications (hulls, decks, superstructure, bulkheads, chords and interior trim), industrial low weight applications, automotive and transportation applications (interior and exterior of automobiles, trucks, trains, airplanes and spacecraft).

Examples

Example 1 preparation of PEF with molecular weight of 114,000 with PMDA chain extender and SSP

The bio-based polyethylene furanate homopolymer was prepared by esterification and polycondensation of 2, 5-furandicarboxylic acid with monoethylene glycol according to known methods for producing PEF homopolymers, then treated with 0.6 wt.% chain extender PMDA according to techniques corresponding to those detailed in examples 47, 49 and 51 below, and then solid state polymerized according to known techniques to produce PEF homopolymers. PEF polymers were tested and found to have the following characteristics ¹:

molecular weight of-114,000

Density (g/cc) -1.43

Glass transition temperature of-86 DEG C

The temperature of the solution is-214 DEG C

Decomposition temperature of-347 DEG C

Crystallinity of-46%

The PEF polymer so produced is referred to as PEX1 in these examples.

Example 1B-preparation of closed cell PEF foam from PEX1 under a range of relative Density and blowing agent conditions

The present invention includes the advantage of forming PEF foam with a high percentage of closed cell volume over a range of Relative Foam Densities (RFD) and with a range of blowing agents. While applicants are not bound by any theory of operation, it is believed that one or more of the advantageous foam properties of the present invention result, at least in part, from the ability to form foams having a high closed cell content. In particular, table E1B below shows the percentage of closed cell volume of several foams prepared by the applicant:

TABLE E1B foam closed cell content

* Closed cell volume% is determined herein by ASTM D6226.

Comparative example 1-preparation of PEF foam using PEX1 and CO2 as blowing agent

1 Gram of PEX1 in a glass vessel was charged into a 60cc autoclave and then dried under vacuum at 130℃for six (6) hours. The dried polymer was then cooled to room temperature and placed in a glass vessel in an autoclave. About 0.25 moles (11 grams) of CO2 blowing agent was then pumped into the autoclave containing the dried polymer, and the autoclave was then heated at a temperature of about 240 ℃ and a pressure above about 610psig to bring the polymer to a molten state. The polymer/CO ₂ blowing agent is maintained in this molten state for about 1 hour, then the temperature and pressure of the melt/blowing agent are reduced to about 190 ℃ and 610psig (hereinafter referred to as prefoaming temperature and prefoaming pressure, respectively, for convenience) within about 5 to 15 minutes, and then maintained at about that temperature and pressure for about 30 minutes to allow the amount of blowing agent incorporated into the melt to reach equilibrium under such conditions. The temperature and pressure in the autoclave were then rapidly reduced (reduced pressure over a period of about 10 seconds and reduced temperature over a period of about 1 to 10 minutes using cold water) to ambient conditions (about 22 ℃ and 1 atmosphere), and foaming occurred. The foam thus produced was tested to determine the following characteristics:

Compressive Strength ("CS") (measured perpendicular to the plane (which is in direct contact with the blowing agent) according to ISO 844)

Compression modulus ("CM") (measured perpendicular to the plane (which is in direct contact with the blowing agent) according to ISO 844)

Tensile Strength ("TS") (measured perpendicular to the plane (which is in direct contact with the blowing agent) according to ASTM C297)

Tensile modulus ("TM") (measured perpendicular to the plane (which is in direct contact with the blowing agent) according to ASTM C297)

Relative foam density ("RFD").

As used herein, RFD is the density of the foam produced divided by the density of the starting polymer. The density was measured in these examples using a method generally corresponding to ASTM D71, except that hexane was used instead of water for the displacement.

The foam produced in this comparative example 1 was tested and found to have the characteristics reported in table C1 below:

Table C1

RFD	0.25
		TS, megapascals (Mpa)	0.74
CS，Mpa	0.5
		TM，Mpa	32
CM，Mpa	8

As described above, the foam prepared using CO ₂ under the reported conditions had an RFD of 0.25, i.e., a density of only 25% of the starting polymer density. The foam density is too high for many important applications.

Example 2-preparation of PEF foam using PEX1 and cis 1224yd as blowing agent

Comparative example 1 was repeated except that the CO ₂ blowing agent was replaced with cis 1224yd in the process and the process conditions were modified so that the RFD of the foam produced was within about 15 relative percent of the RFD produced in comparative example 1 using CO ₂. The resulting foam was tested to determine various properties, including strength and modulus properties compared to CO2, and was found to be significantly superior in each of the measured properties, as reported in table E2 below:

Table E2

* The comparative strength and modulus results in this table are reported based on CO ₂ as baseline value 1 and are identified as RTS, RCS, RTM and RCM.

As can be seen from table E2 above, based on each of the physical strength and modulus characteristics tested, foams prepared using cis 1224yd were surprisingly better than foams prepared using CO ₂. For example, foams prepared with cis 1224yd have a tensile modulus and a compressive modulus twice the value produced using CO ₂, while having compressive and tensile strengths greater than 60% that of CO ₂. This result is unexpected.

Comparative example 2-preparation of PEF foam using PEX1 and cyclopentane as blowing agent

1 G of PEX1 in a glass vessel was charged into an autoclave and then dried under vacuum at 130℃for six (6) hours. The dried polymer was then cooled to room temperature and placed in a glass vessel in an autoclave. About 0.25 moles (32.9 grams) of cyclopentane blowing agent was then pumped into the autoclave containing the dried polymer, and the autoclave was then heated at a temperature of about 240 ℃ and a pressure above about 320psig to bring the polymer to a molten state. The polymer/isopentane blowing agent was maintained in this molten state for about 1 hour, then the temperature and pressure of the melt/blowing agent were reduced to about 190 ℃ and 320psig (hereinafter referred to as prefoaming temperature and prefoaming pressure, respectively, for convenience) within about 5 to 15 minutes, and then maintained at about that temperature and pressure for about 30 minutes to allow the amount of blowing agent incorporated into the melt to reach equilibrium under such conditions. The temperature and pressure in the autoclave were then rapidly reduced (reduced pressure over a period of about 10 seconds and reduced temperature over a period of about 1 to 10 minutes using cold water) to ambient conditions (about 22 ℃ and 1 atmosphere) and foam developed. The resulting foam had a relatively acceptable foam structure and was tested to determine Relative Foam Density (RFD) as well as strength and modulus characteristics. The foam had an RFD of 0.2.

Example 3-preparation of PEF foam using PEX1 and cis 1224yd as blowing agent

Comparative example 2 was repeated except that: (i) In this process cis 1224yd was used instead of cyclopentane blowing agent; and (ii) altering the process conditions such that the RDF value of the resulting foam is within about 15% of the RFD produced using cyclopentane in comparative example 2. The resulting foam was tested to determine various properties, including strength and modulus properties, and was found to be significantly superior in each of the measured properties, as reported in table E3 below:

Table E3

As can be seen from table E3 above, the foams prepared using cis 1224yd were surprisingly and significantly better than the foams prepared using cyclopentane with respect to all physical strength and modulus properties tested. For example, foams prepared with cis 1224yd have tensile and compressive moduli and strengths that are more than 2 times the value obtained using cyclopentane. The results indicate that significant and unexpected improvements in the physical properties of the foam can be achieved in accordance with the present invention.

Examples 4-8-preparation of PEF foams using PEF having a molecular weight of 25,000 to 125,000

Comparative example 1 was repeated except that the conditions and materials were changed as shown in the following tables E5 to E9, and the foaming agents shown in the tables were used on a molar equivalent basis (i.e., within 15%) (all values were understood to be "about" as indicated).

Tables E4 to 8

* Weight% of PEF fraction in Polymer

* A-acceptable

Table E5

* Weight% of PEF fraction in Polymer

* A-acceptable

Table E7

* Weight% of PEF fraction in Polymer

* A-acceptable

Table E8

* Weight% of PEF fraction in Polymer

* A-acceptable

Table E9

In each of the above tables E4 to E8 9, the thermoplastic polymer used to prepare the foam had characteristics (measured according to the same procedure as shown above in comparative example 1) within the ranges shown below:

glass transition temperature of-75-95 DEG C

Melt temperature of 190 ℃ below zero to 240 DEG C

The decomposition temperature is-320 ℃ to 400 DEG C

Crystallinity of-30% -60%

All foams produced according to these examples were observed to be acceptable quality foams.

Examples 9-20-preparation of PEF foam Using PEF having a molecular weight of 25,000 to 125,000 and a blowing agent comprising cis 1224yd and a co-blowing agent

Example 11 was repeated to prepare a foam having a closed cell volume of 90% or more with 1224yd (Z) except that a blowing agent consisting of 1224yd (Z) was not used, but a co-blowing agent as shown in the following table was used instead of the portion 1224yd (Z) in the range of 5% to 45% by mole as shown in the following tables E9-20 (all values are understood to be "about" values).

Tables E9 to 20

/>

* Butane refers to isobutane and n-butane separately and independently.

* Pentane individually and independently refers to each of isopentane, n-pentane, neopentane, and cyclopentane

* A-acceptable

EXAMPLE 24 preparation of PEF with molecular weight 43,500 Using PMDA chain extender and SSP

The bio-based polyethylene furanate homopolymer was prepared by esterification and polycondensation of 2, 5-furandicarboxylic acid with monoethylene glycol according to known methods for producing PEF homopolymers, then treated with 0.7 wt.% chain extender PMDA according to techniques generally corresponding to those described in detail in example 1 below, and then solid state polymerized according to known techniques to produce PEF homopolymers having a molecular weight of about 43,500. PEF polymers were tested and found to have the following characteristics:

Molecular weight-43,500

Density (g/cc) -1.43

Glass transition temperature of-90.4 DEG C

Solution temperature-219 DEG C

Decomposition temperature-344 DEG C

Crystallinity of-41.9%

The PEF polymer so produced is referred to as PEX20 in these examples.

Example 21-preparation of PEF foam Using PEX20 and cis 1224yd as blowing agent

Using a procedure generally corresponding to that described in comparative example 1, a foam was formed by placing 1 gram of PEX20 in a glass container, charging it into a 60cc autoclave, and then vacuum drying at 130℃for six (6) hours. The dried polymer was then cooled to room temperature and placed in a glass vessel in an autoclave. About 38 grams of 1224yd (Z) blowing agent was then pumped into the autoclave containing the dry polymer, and the autoclave was then heated at a temperature of about 240℃and a pressure above the pre-foaming pressure to bring the polymer to a molten state. The polymer/1224 yd (Z) blowing agent was maintained in the molten state for about 1 hour, then the temperature and pressure of the melt/blowing agent were reduced to about 190℃and 573psig (hereinafter referred to as prefoaming temperature and prefoaming pressure, respectively, for convenience) within about 5 to 15 minutes, and then maintained at about that temperature and pressure for about 30 minutes to allow the amount of blowing agent incorporated into the melt to equilibrate under such conditions. The temperature and pressure in the autoclave were then rapidly reduced (reduced pressure over a period of about 10 seconds and reduced temperature over a period of about 1 to 10 minutes using cold water) to ambient conditions (about 22 ℃ and 1 atmosphere) and foam developed. The foam thus produced was tested and found to have the characteristics reported in table E21 below:

Table E21

From the results reported in Table E21, it can be seen that the use of 1224yd (Z) blowing agent produced a foam having a density significantly and unexpectedly improved over the foam prepared with CO ₂ of comparative example 1, even though the foam was prepared from a polymer having a much higher molecular weight. In particular, the density value of the foam produced with 1224yd (Z) of this example averages about 2/7 of the density of the CO ₂ expanded foam of comparative example 1.

EXAMPLE 22 preparation of PEF with molecular weight 160,000 with PMDA chain extender and SSP

The bio-based polyethylene furanate homopolymer was prepared by esterification and polycondensation of 2, 5-furandicarboxylic acid with monoethylene glycol according to known methods for producing PEF homopolymers, then treated with 0.7 wt.% chain extender PMDA according to techniques generally corresponding to those described in detail in example 1 below, and then solid state polymerized according to known techniques to produce PEF homopolymers having a molecular weight of about 160,000. PEF polymers were tested and found to have the following characteristics:

Molecular weight-160,500

Density (g/cc) -1.43

Glass transition temperature-91.4 DEG C

The temperature of the solution is 216 DEG C

Decomposition temperature-344 DEG C

Crystallinity of-34%

The PEF polymer so produced is referred to in these examples as PEX22.

Example 23-preparation of PEF foam Using PEX22 and cis 1224yd as blowing agent

Using a procedure generally corresponding to that described in comparative example 1, a foam was formed by placing 1 gram of PEX22 in a glass container, charging it into a 60cc autoclave, and then vacuum drying at 130℃for six (6) hours. The dried polymer was then cooled to room temperature and placed in a glass vessel in an autoclave. About 38 grams of 1224yd (Z) blowing agent was then pumped into the autoclave containing the dry polymer, and the autoclave was then heated at a temperature of about 240℃and a pressure above the pre-foaming pressure to bring the polymer to a molten state. The polymer/1224 yd (Z) blowing agent was maintained in the molten state for about 1 hour, then the temperature and pressure of the melt/blowing agent were reduced to about 190℃and 573psig (hereinafter referred to as prefoaming temperature and prefoaming pressure, respectively, for convenience) within about 5 to 15 minutes, and then maintained at about that temperature and pressure for about 30 minutes to allow the amount of blowing agent incorporated into the melt to equilibrate under such conditions. The temperature and pressure in the autoclave were then rapidly reduced (reduced pressure over a period of about 10 seconds and reduced temperature over a period of about 1 to 10 minutes using cold water) to ambient conditions (about 22 ℃ and 1 atmosphere), and foaming occurred. The foam thus produced was tested and found to have the characteristics reported in table E23 below:

Table E23

From the results reported in Table E23, it can be seen that the use of 1224yd (Z) blowing agent produced a foam having a density significantly and unexpectedly improved over the foam prepared with CO ₂ of comparative example 1, even though the foam was prepared from a polymer having a much higher molecular weight. In particular, the density values of the foams produced with 1224yd (Z) of this example averaged about 1/3 of the density of the CO ₂ blown foam of comparative example 1, while achieving better tensile strength and modulus values than the foam blown with CO ₂.

The following clauses provide a description that is within the scope of the present invention.

Clause 1. A low density thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls forming closed pores, wherein ethylene furanoate moieties are at least 50 wt% of the thermoplastic polymer; and

Clause 2. The foam of clause 1, wherein the cell walls consist essentially of a polyvinyl furoate that has been treated with a chain extender.

Clause 3 the foam of clause 1, wherein the cell walls consist essentially of a polyvinyl furoate having a molecular weight greater than 25,000.

Clause 4 the foam of clause 1, wherein the ethylene furanoate moiety is at least 70 weight percent of the thermoplastic polymer.

Clause 5 the foam of clause 1, wherein the ethylene furanoate moiety is at least 90 weight percent of the thermoplastic polymer.

Clause 6 the foam of clause 1, wherein the foam has a Relative Foam Density (RFD) of about 0.2 or less.

Clause 7 the foam of clause 1, wherein the foam has a foam density of less than 0.4 g/cc.

Clause 8 the foam of clause 1, wherein the foam has a foam density of less than 0.2 g/cc.

Clause 9 the foam of clause 1, wherein the one or more blowing agents contained in the closed cells comprise one or more of 1224yd, 1233zd (E), 1234yf, 1234ze (E), 1336mzz (E), and 1336mzz (Z).

Clause 10 the foam of clause 9, wherein the cell walls consist essentially of a polyvinyl furoate having a molecular weight greater than 100,000.

Clause 11. The foam of clause 1, wherein the one or more blowing agents contained in the closed cells comprise at least 1234ze (E).

Clause 12 the foam of clause 11, wherein the cell walls consist essentially of a polyvinyl furoate having a molecular weight greater than 100,000, and wherein the foam has a Relative Foam Density (RFD) of about 0.2 or less.

Clause 13 the foam of clause 1, wherein the one or more blowing agents contained in the closed cells comprise at least 1336mzz (Z).

Clause 14 the foam of clause 13, wherein the cell walls consist essentially of a polyvinyl furoate having a molecular weight greater than 100,000, and wherein the foam has a Relative Foam Density (RFD) of about 0.2 or less.

Clause 15 the foam of clause 1, wherein the one or more blowing agents contained in the closed cells comprise at least 1336mzz (Z) and/or 1234ze (E).

Clause 16 the foam of clause 15, wherein the cell walls consist essentially of a polyvinyl furoate having a molecular weight greater than 100,000, and wherein the foam has a Relative Foam Density (RFD) of about 0.2 or less.

Clause 17. A wind energy turbine blade and/or nacelle comprising the foam according to any of clauses 1 to 16.

Clause 18. An automotive wall comprising the foam of any of clauses 1 to 16.

Clause 19. A vessel comprising the foam of any of clauses 1 to 16.

Clause 20 an aircraft or aerospace vehicle comprising the foam of any of clauses 1 to 16.

Clause 21. A low density thermoplastic foam comprising:

Clause 22. A low density thermoplastic foam comprising:

(a) A thermoplastic closed cell comprising cell walls forming closed cells, the cell walls consisting essentially of a polyvinyl furanoate that has been treated with a chain extender and has a molecular weight greater than 25,000; and

Clause 23. A low density thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls comprising a polyvinyl furan acid ester having been treated with a chain extender and having a molecular weight greater than 25,000, wherein the ethylene furan acid ester moiety is at least 70% by weight of the thermoplastic polymer; and

Clause 24. A low density closed cell thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls comprising a polyvinyl furan acid ester having been treated with a chain extender and having a molecular weight greater than 25,000, wherein the polyvinyl furan acid ester moiety is at least 90% of the thermoplastic material comprising the polyvinyl furan acid ester moiety; and

Clause 25A. A low density closed cell thermoplastic foam comprising:

(B) A foaming agent contained in the closed cells,

Wherein the foam has a Relative Foam Density (RFD) of about 0.2 or less and a foam density of less than 0.3 g/cc.

Clause 25B. A low density thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls, wherein at least about 50% by volume of the pores are closed cells, and wherein ethylene furanoate moieties are at least 50% by weight of the thermoplastic polymer; and

Clause 25C, a low density thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising a pore wall comprising a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 25,000, wherein the polyvinyl furan acid ester moieties are at least 50% of the thermoplastic material, and wherein at least about 50% by volume of the pores are closed cells; and

Clause 25D. A low density thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising a pore wall comprising a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 25,000, wherein the polyvinyl furan acid ester moieties are at least 50% of the thermoplastic material, and wherein at least about 75% by volume of the pores are closed cells; and

Clause 25E, a low density thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising a pore wall comprising a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 25,000, wherein the polyvinyl furan acid ester moieties are at least 50% of the thermoplastic material, and wherein at least about 90% by volume of the pores are closed cells; and

Clause 26, a low density closed cell thermoplastic foam comprising:

(B) A foaming agent contained in the closed cells,

Wherein the foam has an RFD of about 0.2 or less and a density of less than 0.3 g/cc.

Clause 27. A low density closed cell thermoplastic foam comprising:

(B) A foaming agent contained in the closed cells,

Wherein the foam has a density of less than 0.25 g/cc.

Clause 28A. A low density closed cell thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising a pore wall comprising a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 50,000, wherein the polyvinyl furan acid ester moieties are at least 50% of the thermoplastic material, and wherein at least about 50% by volume of the pores are closed cells; and

Clause 28B, a low density closed cell thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising a pore wall comprising a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 50,000, wherein the polyvinyl furan acid ester moieties are at least 50% of the thermoplastic material, and wherein at least about 75% by volume of said pores are closed cells; and

Clause 28C, a low density closed cell thermoplastic foam comprising:

(a) Thermoplastic closed cells comprising cell walls consisting essentially of a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 100,000; and

(B) A blowing agent contained in the closed cells, wherein the foam has a density of less than 0.3 g/cc.

Clause 29, a low density closed cell thermoplastic foam comprising:

(B) A foaming agent contained in the closed cells and comprising one or more HFOs having three or four carbon atoms and/or one or more HFCO having three or four carbon atoms, wherein the foam has a density of less than 0.3 g/cc.

Clause 30. A low density closed cell thermoplastic foam comprising:

(B) A foaming agent contained in the closed cells and comprising one or more HFOs having three or four carbon atoms and/or one or more HFCO having three or four carbon atoms, wherein the foam has a density of less than 0.25 g/cc.

Clause 31. A low density closed cell thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls forming closed pores, wherein ethylene furanoate moieties are at least 50 wt% of the thermoplastic polymer, and wherein the thermoplastic material comprises a polyethylene furanoate-based polymer that has been treated with a chain extender and has a molecular weight greater than 25,000; and

(B) One or more blowing agents contained in the closed cells, the blowing agents comprising one or more of 1224yd, 1233zd (E), 1234yf, 1234ze (E), 1336mzz (E), and 1336mzz (Z).

Clause 32. A low density closed cell thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls forming closed pores, wherein ethylene furanoate moieties are at least 70 weight percent of the thermoplastic polymer, and wherein the thermoplastic material comprises a polyethylene furanoate-based polymer that has been treated with a chain extender and has a molecular weight greater than 100,000; and

Clause 33 is a low density closed cell thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls forming closed pores, wherein ethylene furanoate moieties are at least 90 wt% of the thermoplastic polymer, and wherein the thermoplastic material comprises a polyethylene furanoate-based polymer that has been treated with a chain extender and has a molecular weight greater than 100,000; and

Clause 34. A low density closed cell thermoplastic foam comprising:

(a) Thermoplastic polymer pores comprising pore walls forming closed pores, wherein ethylene furanoate moieties are at least 90 wt% of the thermoplastic polymer, and wherein the thermoplastic material has a molecular weight greater than 100,000; and

(B) One or more blowing agents contained in the closed cells, the blowing agents comprising one or more of 1234ze (E), 1336mzz (E), and 1336mzz (Z).

Clause 35 is a low density closed cell thermoplastic foam comprising:

(B) One or more blowing agents contained in said closed cells, said blowing agents consisting essentially of 1234ze (E).

Clause 36 a low density closed cell thermoplastic foam comprising:

(B) One or more blowing agents contained in the closed cells, the blowing agents consisting essentially of 1336mzz (E).

Clause 37, a low density closed cell thermoplastic foam comprising:

(B) Trans-1234 ze contained in the closed cells,

Wherein the foam has a density of less than 0.3 g/cc.

Clause 38 is a low density closed cell thermoplastic foam comprising:

(B) HFO-1234yf contained in the closed cells,

Wherein the foam has a density of less than 0.3 g/cc.

Clause 39 a low density closed cell thermoplastic foam comprising:

(B) 1336mzz (E) contained in the closed cells,

Wherein the foam has a density of less than 0.3 g/cc.

Clause 40. A low density closed cell thermoplastic foam comprising:

(B) 1336mzz (Z) contained in the closed cells,

Wherein the foam has a density of less than 0.3 g/cc.

Clause 41 a low density closed cell thermoplastic foam comprising:

(B) 1224yd contained in the closed cells,

Wherein the foam has a density of less than 0.3 g/cc.

Clause 42. A foamable thermoplastic composition comprising:

(a) A thermoplastic material consisting essentially of a polyvinyl furan acid ester that has been treated with a chain extender and has a molecular weight greater than 25,000, wherein at least 50% of said thermoplastic material contains a polyvinyl furan acid ester moiety; and

(B) One or more HFOs having three or four carbon atoms and/or one or more HFCO having three or four carbon atoms.

Clause 43. A foamable thermoplastic composition comprising:

(a) A thermoplastic material consisting essentially of a polyvinyl furan acid ester having a molecular weight greater than 100,000, wherein at least 50% of said thermoplastic material contains a polyvinyl furan acid ester moiety;

Clause 44. A foamable thermoplastic composition comprising:

(a) A thermoplastic material consisting essentially of chain extended polyvinyl furanate having a molecular weight greater than 100,000, wherein at least 90% of the thermoplastic material contains ethylene furanate moieties; and

Clause 45. A method of forming a thermoplastic foam, the method comprising foaming the foamable composition of the invention comprising each of clauses 42 to 44.

Clause 46. A method of forming an extruded thermoplastic foam, the method comprising extruding the foamable composition of the invention comprising each of clauses 42 to 44.

Claims

1. A low density thermoplastic foam comprising:

(a) A thermoplastic polymer cell comprising cell walls comprising a polyvinyl furan acid ester, wherein at least about 50% by volume of the cells are closed cells; and

(B) At least 1224yd contained in the closed cells.

2. The foam of claim 1, wherein the foam has a density of about 0.05g/cc to less than 0.2g/cc.

3. The foam of claim 2, wherein the tensile strength of the foam is from about 1.5Mpa to about 3.5Mpa.

4. The foam of claim 2, wherein the foam has a compressive strength of about 0.65Mpa to about 1.5Mpa.

5. The foam of claim 3, wherein the foam has a compressive strength of about 0.65Mpa to about 1.5Mpa.

6. The foam of claim 2, wherein the foam has a density of about 0.05g/cc to less than 0.1 g/cc.

7. The foam of claim 5, wherein the foam has a density of about 0.05g/cc to less than 0.1 g/cc.

8. The foam of claim 2, wherein ethylene furanoate moieties are at least 50 wt% of the thermoplastic polymer.

9. The foam of claim 2 wherein the cell walls consist essentially of polyvinyl furoate.

10. The foam of claim 2 wherein the cell walls consist essentially of a polyvinyl furan acid ester having a molecular weight of at least about 90,000.

11. The foam of claim 2, wherein ethylene furanoate moieties are at least 85% by weight of the thermoplastic polymer.

12. The foam of claim 2 wherein at least about 75% of the cells are closed cells.

13. A thermoplastic foam comprising:

(a) A thermoplastic polymer pore comprising pore walls comprising a polyvinyl furanoate having a crystallinity of at least 10%, wherein at least about 50% by volume of the pores are closed cells, and wherein the thermoplastic polymer does not comprise a tannin fraction or comprises a tannin fraction in an amount of less than 20 weight%; and

(B) A gas in the closed cells, the gas comprising 1224yd contained in the closed cells.

14. The foam of claim 13, wherein the gas in the closed cells further comprises one or more of 1234ze (E), 1336mzz (Z), 1233zd (E), 1234yf, and combinations of two or more of these.

15. The foam of claim 14, wherein at least about 75% of the cells are closed cells.

16. The foam of claim 13 wherein the gas in the closed cells comprises at least 60 wt% 1224yd, and wherein the cell walls consist essentially of a polyvinyl furanoate having a molecular weight of at least about 90,000.

17. The foam of claim 13 wherein the gas in the closed cells consists essentially of 1224 yd.

18. A wind energy turbine blade and/or nacelle, or an automotive wall, or an aircraft or aerospace vehicle, comprising the foam according to any one of claims 1 to 17.

19. A foamable composition comprising:

(a) A thermoplastic polymer comprising a polyvinyl furanoate containing no tannin moieties or containing tannin moieties in an amount of less than 20 weight percent; and

(B) A blowing agent comprising 1224 yd.

20. The foamable composition of claim 19 wherein said blowing agent comprises from about 5% to about 95% of said 1224yd.

21. The foamable composition of claim 19 wherein said polyvinyl furoate has a molecular weight of from about 25,000 to about at least about 180,000 and has a crystallinity of from 30 to 60 percent by volume.

22. The foamable composition of claim 19 wherein said polyvinyl furoate has a molecular weight of from about 80,000 to about at least about 130,000 and has a crystallinity of from 30% to 60% by volume.

23. The foamable composition of claim 20 wherein said polyvinyl furoate has a molecular weight of from about 80,000 to about at least about 130,000 and has a crystallinity of from 30% to 60% by volume.

24. The foamable composition of claim 23 wherein said polyvinyl furoate has a molecular weight of from about 90,000 to about at least about 120,000 and has a crystallinity of from 30% to 60% by volume, and wherein said blowing agent comprises at least about 60% by weight 1224yd.

25. The foamable composition of claim 20 wherein said polyvinyl furoate has a molecular weight of from about 25,000 to about at least about 180,000 and has a crystallinity of from 30 to 60 percent by volume.

26. The foamable composition of claim 29 wherein said polyvinyl furoate has a molecular weight of from about 80,000 to about at least about 130,000 and has a crystallinity of from 30 to 60 percent by volume.

27. The foamable composition of claim 20 wherein said polyvinyl furoate has a molecular weight of from about 80,000 to about at least about 130,000 and has a crystallinity of from 30% to 60% by volume.

28. The foamable composition of claim 20 wherein said polyvinyl furoate has a molecular weight of from about 90,000 to about at least about 120,000 and has a crystallinity of from 30% to 60% by volume, and wherein said blowing agent comprises at least about 60% by weight 1224yd.

29. The foam of any one of claims 1-12, wherein the 1224yd comprises 1224yd (Z).

30. The foamable composition of any of claims 13 to 28 wherein said 1224yd comprises 1224yd (Z).