CN110709494A

CN110709494A - Working fluid composition

Info

Publication number: CN110709494A
Application number: CN201880036936.6A
Authority: CN
Inventors: G.博卡莱蒂; S.罗文蒂; U.德巴图
Original assignee: Solvey Special Polymer Italy Ltd
Current assignee: Solvey Special Polymer Italy Ltd
Priority date: 2017-04-03
Filing date: 2018-03-30
Publication date: 2020-01-17
Also published as: US20210324291A1; JP2020515697A; WO2018185026A1; EP3607033A1

Abstract

The present invention relates to a composition suitable for use as a working fluid, said composition being in the form of a solution and comprising at least one (per) fluoropolyether polymer [ polymer (P) ] and at least one amorphous polymer [ polymer (F) ].

Description

Working fluid composition

Cross Reference to Related Applications

This application claims priority to european application No. 17164462.8 filed on 2017, 03, 4.03, the entire contents of which are incorporated by reference into this application for all purposes.

Technical Field

The present invention relates to a composition suitable for use as a working fluid.

Background

The working fluid is a gas or liquid that when pressurized actuates the machine. Typical examples include steam in steam engines, air in hot air engines, and hydraulic fluid in hydraulic motors or cylinders. More generally, in thermodynamic systems, the working fluid is a liquid or a gas that absorbs or transmits energy.

The working fluid properties are essential for a comprehensive description of the thermodynamic system. Among the large number of suitable physical properties, their viscosity is particularly important for use in applications such as fluid coupling, notably viscous coupling and damping.

Working fluids suitable for the above applications and comprising organopolysiloxanes as base OILs have been disclosed, for example, in US 4959166 (COSMO OIL cp., LTD., etc.), EP 0397507 a (eastern co., LTD. (TONEN CORPORATION)) and EP 0599251 a (COSMO OIL co., etc.).

More recently, WO 2016/150941 (SOLVAY speciallylummesmerizers italy.p.a.) discloses a method for counteracting vibrations and/or shocks in a device, wherein the method comprises:

there is provided an apparatus comprising a damper device comprising at least one (per) fluoropolyether copolymer [ polymer (P) ] having a viscosity higher than 2,000mm/s and comprising recurring units derived from a (per) fluoropolyether and recurring units derived from at least one olefin, the viscosity being measured at 20 ℃ according to standard method ASTM D445, or at 1rad/s and at 25 ℃ with an Anton Paar MCR 502 rheometer equipped with a parallel plate 25mm dynamic mechanical spectrometer.

The present teachings provide a fluid suitable for use in a damper device, wherein the fluid is obtained by reacting a (per) fluoropolyether polymer and at least one olefin.

Compositions comprising a (per) fluoropolyether (PFPE) polymer as base oil and at least one perfluoropolymer, typically in the form of a suspension or dispersion, have been disclosed in the art.

For example, US 6100325 (ausemont s.p.a.) discloses a composition in the form of a dispersion comprising 0.1-30 wt.% of polytetrafluoroethylene or Tetrafluoroethylene (TFE) copolymer, 50-90 wt.% of a fluorinated liquid, 0.01-5 wt.% of a surfactant and a polar agent (water and/or alcohol) in an amount to make up to 100 wt.%. US 6025307 (osjomont company) discloses a fluorinated grease in the form of a dispersion comprising 15-50 wt.% of polytetrafluoroethylene or tetrafluoroethylene copolymer, 30-84.5 wt.% of a perfluoropolyether oil having a viscosity at 20 ℃ comprised between 20 and 4000 cSt; 0.5-10 wt.% of a surfactant or dispersant having a perfluoropolyether or perfluoroalkyl chain; and optionally an anti-corrosion or anti-wear additive.

Lubricant compositions comprising (per) fluoropolyether (PFPE) polymers characterized by high viscosity (e.g. in paste form) are also disclosed in the art.

US 5032302 (exflu RESEARCH CORPORATION) discloses a lubricant comprising a perfluoropolyether oil containing perfluoropolyether solids as a filler, which can be prepared by mixing the perfluoropolyether solids with the perfluoropolyether oil. The compositions are said to be stable and do not exhibit phase separation because the oil and the solid, which have the same chemical composition, are extremely compatible.

Further, JP H0673370(NTN CORP.)) discloses a damper sealant which is brought into contact with a slidable member to prevent leakage of an energy absorbing fluid in a shock absorber or a damper, and which is made of a lubricating rubber composition containing (a) a thermoplastic fluororesin, (B) a fluororubber and (C) a low-molecular fluoropolymer. In the specification, as examples of component (C), the following are mentioned: tetrafluoroethylene polymers, fluoropolyethers, and polyfluoroalkyl groups. Fluoropolyethers notably have the following structure:

CF₃O(C₂F₄)_m(CF₂O)_n-CF₃

CF₃O(CF₂CF(CF₃)O)_m(CF₂O)_n-CF₃

CF₃O(CF(CF₃)CF₂O)_m(CF₂O)_n-CF₃。

disclosure of Invention

The applicant believes that in a working fluid comprising two different phases (typically a solid phase dispersed or suspended in a liquid phase), phase separation can occur when the working fluid is used under severe conditions.

Furthermore, the applicant believes that the highly viscous silicone oils currently used as damping fluids suffer from some drawbacks, such as sensitivity to acids, bases and moisture, and in particular thermal instability. Indeed, due to prolonged exposure to high temperatures (200 ℃ or even higher), highly viscous silicone oils gradually harden over time until they become inoperable and must be replaced. Furthermore, the applicant has noted that the thermal instability of highly viscous silicone oils becomes more pronounced as the viscosity of the silicone oil increases.

The applicant has therefore faced the problem of providing a composition intended to be used as a working fluid in several applications. To this end, the applicant faced the problem of providing a composition which can be prepared by a simple process, so that a wide range of viscosities can be provided depending on the final intended use.

The applicant has surprisingly found that compositions in the form of solutions can be obtained by contacting at least one (per) fluoropolyether polymer and at least one amorphous polymer.

Advantageously, the applicant has found that the compositions of the invention are capable of retaining their viscous properties over a wide temperature range without showing degradation even after prolonged use in harsh environments.

Thus, in a first aspect, the present invention relates to a composition [ composition (C) ] comprising at least one (per) fluoropolyether polymer [ polymer (P) ] and at least one amorphous polymer [ polymer (F) ], wherein said composition (C) is in the form of a solution.

Advantageously, the polymer (F) is in the amorphous stateSelected from the group consisting of polymers characterized by a glass transition temperature (T) in the range of from-100 ℃ to 250 ℃ measured according to ASTM D3418_g). It will be clear to the person skilled in the art that the amorphous polymer (F) does not show a melting point (T) when analyzed by thermal analysis following ASTM D3418_m)。

As mentioned above, the applicant has noted that it is possible to prepare compositions (C) according to the invention having a wide range of viscosities, which can be adjusted on the basis of the end use for which said compositions (C) are intended.

Advantageously, said composition (C) is characterized by a particle size ranging from 100mm²A/s and up to 2,000,000mm²Viscosity in the range/s (measured at 20 ℃ according to standard methods (such as ASTM D445) or with an Anton PaarMCR 502 rheometer equipped with parallel plates 25mm at 1rad/s and at 25 ℃).

Thus, the composition (C) can be used as a working fluid in several applications, which has the advantage that no phase separation occurs in a homogeneous solution even after exposure to high temperatures.

Detailed Description

For the purposes of this specification and the claims that follow:

the use of parentheses around the symbol or number of the identification formula, for example in expressions like "polymer (P)" or the like, has the purpose of only better distinguishing this symbol or number from the rest of the text, and therefore said parentheses can also be omitted;

the acronym "PFPE" stands for "(per) fluoropolyether" and, when used as the real noun, is intended to mean, depending on the context, in the singular or plural form;

the prefix "(per)" in the term "(per) fluoropolyether" or in the term (per) fluoropolymer is intended to indicate that the polyether or fluoropolymer may be fully or partially fluorinated;

the term "solution" is intended to indicate a homogeneous mixture consisting of at least two components, i.e. at least one solute (preferably an amorphous polymer) dissolved in a solvent (preferably a (per) fluoropolyether polymer);

the term "homogeneous" is intended to indicate that, throughout a given amount of mixture, the mixture has its components in the same proportions;

the term "amorphous" is intended to indicate showing a glass transition (T) when subjected to Differential Scanning Calorimetry (DSC) according to ASTM D3418_g) But does not show a melting transition (T)_m) The one or more polymers of (a).

Preferably, said polymer (P) is a polymer comprising a (per) fluoropolyether chain [ chain (R) having the formula_pf)](per) fluoropolyether polymer of (a):

-(CFX)_aO(R_f)(CFX′)_b-

wherein

a and b, equal to or different from each other, are equal to or greater than 1, preferably from 1 to 10, more preferably from 1 to 3;

x and X', equal to or different from each other, are-F or-CF₃Provided that when a and/or b is greater than 1, X and X' are-F;

(R_f) Comprises, preferably consists of, a recurring unit R °, said recurring unit being independently selected from the group consisting of:

(i) -CFXO-, wherein X is F or CF₃；

(ii) -CFXCFXO-, wherein X, the same or different at each occurrence, is F or CF₃Provided that at least one X is-F;

(iii)-(CF₂) j-CFZ-O-, wherein j is an integer from 0 to 3 and Z is of the formula-O-R_(f-a)A group of-T, wherein R_(f-a)Is a fluoropolyoxyalkylene chain comprising a number of repeating units from 0 to 10, said repeating units being selected among: -CFXO-, -CF₂CFXO-, wherein each X is independently F or CF₃And T is C₁-C₃A perfluoroalkyl group.

Preferably, the chain (Rf) is selected from chains having the formula:

(R_f-I)-[(CF₂CF₂O)_b1(CF₂O)_b2(CF(CF₃)O)_b3(CF₂CF(CF₃)O)_b4]-

wherein:

b1, b2, b3, b4 are independently integers ≧ 0 such that the number average molecular weight is between 400 and 20,000, preferably between 1,000 and 10,000; preferably b1 is 0, b2, b3, b4 is > 0, wherein the ratio b4/(b2+ b3) is ≧ 1;

(R_r-II)-[(CF₂CF₂O)_c1(CF₂O)_c2(CF₂(CF₂)_cwCF₂O)_c3]-

wherein:

cw ═ 1 or 2;

c1, c2 and c3 are independently integers ≧ 0 selected such that the number average molecular weight is between 400 and 20,000, preferably between 1,000 and 10,000; preferably c1, c2 and c3 are all > 0, wherein the ratio c3/(c1+ c2) is generally lower than 0.2;

(R_f-III)-[(CF₂CF(CF₃)O)_d]-

wherein:

d is an integer > 0, such that the number average molecular weight is between 1,000 and 20,000, preferably between 400 and 10,000;

(R_f-IV)-[(CF₂O)_c2(CF₂(CF₂)_cwCF₂O)_c3]-

wherein:

cw ═ 1 or 2;

c2 and c3 are independently integers > 0, chosen such that the number average molecular weight is between 400 and 20,000, preferably between 1,000 and 10,000; preferably, the ratio c3/c2 is generally lower than 0.2;

(R_f-V)-[(CF₂CF₂C(Hal*)₂O)_e1-(CF₂CF₂CH₂O)_e2-(CF₂CF₂CH(Hal*)O)_e3]-

wherein:

-Hal, equal or different at each occurrence, is a halogen selected from fluorine and chlorine atoms, preferably a fluorine atom;

-e1, e2 and e3, equal to or different from each other, are independently integers ≧ 0, such that the sum (e1+ e2+ e3) is comprised between 2 and 300.

When the chain (R)_f) Good results have been obtained when at least one repeating unit comprising 3 carbon atoms is included.

According to a particularly preferred embodiment, the chain (R)_f) In accordance with the formula (R)_f-VI-a) to (R)_f-VI-c)：

(R_f-VI-a)-[(CF₂CF(CF₃)O)_f1-(CF₂O)_f2]-

Wherein

f1 and f2 are independently integers ≧ 0 such that the number average molecular weight is between 400 and 20,000, preferably between 1,000 and 10,000; preferably both f1 and f2 are integers greater than 0, wherein the ratio f1/f2 ≧ 1, more preferably greater than 1;

(R_f-VI-b)-(CF(CF₃)CF₂O)f₃-

wherein

f3 is an integer greater than 0, so that the number average molecular weight is between 400 and 20,000, preferably between 1,000 and 10,000;

(R_f-VI-c)-(CF₂CF₂CF₂O)_f4-

wherein

f4 is an integer greater than 0, so that the number average molecular weight is between 400 and 20,000, preferably between 1,000 and 10,000.

According to a preferred embodiment, the chain (Rpf) has two chain ends comprising a perfluorooxyalkyl group, more preferably comprising from 1 to 3 carbon atoms.

Suitable polymers (P) are those under the trade name

From Suweiter, Italy under the trade name

From Chemours Co., Ltd., and under the trade name

Commercially available from Daikin Ind., Ltd.

Preferably, said polymer (F) is selected in the group comprising, more preferably consisting of:

styrene polymers and copolymers, such as Polystyrene (PS), acrylonitrile/butadiene/styrene (ABS), styrene/acrylonitrile (SAN), styrene/acrylic acid (S/a), styrene/maleic anhydride (SMA);

vinyl polymers and copolymers, such as polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC);

acrylic polymers and copolymers, such as Polymethylmethacrylate (PMMA) and PVC/acrylic blends;

- (per) fluoropolymers, more preferably perfluoropolymers;

polyesters, such as glycol-modified polyethylene terephthalate (PETG) and Polyarylates (PAR);

polyamide imides (PAI) and Polyetherimides (PEI);

polyethers, such as Polycarbonate (PC), polyphenylene oxide blends (PPO);

sulfur-containing polymers, such as Polysulfone (PSF), Polyethersulfone (PES) and Polyarylsulfone (PAS);

-polyurethanes (TPU), fluorinated polyurethanes and acrylonitrile polymers.

Good results have been obtained by selecting said polymer (F) among perfluoropolymers.

In this specification and the following claims:

the term "perfluoropolymer" is intended to indicate a polymer consisting essentially of recurring units derived from at least one perfluorinated monomer;

the expression "perfluorinated monomer" is intended to indicate a fully fluorinated monomer free of hydrogen atoms;

the expression "consisting essentially of" is intended to indicate that minor amounts of end chains, defects, irregularities and monomer rearrangements are tolerated in the perfluoropolymer;

the expression "at least one perfluorinated monomer" is intended to indicate that the perfluorinated polymer contains repeating units derived from one or more perfluorinated monomers.

Suitable perfluoropolymers according to the present invention comprise at least one repeating unit comprising at least one perfluorinated monomer selected in the group comprising, more preferably consisting of:

(A) a cyclic monomer corresponding to one of the following formulae (A1) to (A3):

(A1)

wherein R is_f4、R_f5、R_f6Each independently of the other, being the same or different from each other, is a fluorine atom, C₁-C₆Perfluoroalkyl, optionally containing one or more oxygen atoms, e.g. -CF₃、-C₂F₅、-C₃F₇、-OCF₃、-OCF₂CF₂OCF₃；

(A2)

Wherein n is 1 or 2;

(A3)

wherein n is 1 or 2;

(B)C₂-C₈perfluoroolefins such as Tetrafluoroethylene (TFE) and Hexafluoropropylene (HFP);

(C)CF₂＝CFOR_f1wherein R is_f1Selected from:

(R_f1*)C₁-C₆perfluoroalkyl radicals, e.g. -CF₃、-C₂F₅、-C₃F₇(ii) a Or

(R_f1**)-CF₂O(CF₂)_tOR_f2

Wherein t is an integer equal to 1 or 2 and R_f2Is straight-chain or branched C₁-C₆Perfluoroalkyl radicals, e.g. -CF₃、-C₂F₅、-C₃F₇(ii) a Cyclic C₅-C₆Perfluoroalkyl, or a linear or branched C comprising one or more ether groups₁-C₁₂(per) fluorooxyalkyl radicals, e.g. -CF₂CF₂OCF₃and-CF (CF)₃)OCF₃。

According to a first preferred embodiment, said polymer (F) is a copolymer of Tetrafluoroethylene (TFE), i.e. it comprises recurring units derived from TFE and recurring units derived from at least one perfluorinated monomer [ comonomer (F) ] different from TFE.

The term "copolymer" is also intended to indicate TFE terpolymers and TFE tetramers comprising repeating units derived from TFE and repeating units derived from two and three perfluorinated monomers other than TFE, respectively.

According to a first variant of the first preferred embodiment, said at least one comonomer (F) is selected from the group consisting of:

(A1)

wherein R is_f4、R_f5、R_f6Each independently of the other, being the same or different from each other, is a fluorine atom, C₁-C₆Perfluoroalkyl, optionally containing one or more oxygen atoms, e.g. -CF₃、-C₂F₅、-C₃F₇、-OCF₃、-OCF₂CF₂OCF₃(ii) a More preferably, R_f4is-OCF₃Or F and R_f5And R_f6Both are fluorine atoms or both are methyl groups;

(A2)

wherein n is 1 or 2;

(A3)

wherein n is 1 or 2; and

-combinations thereof.

According to this first variant, polymer (F) preferably comprises more than 50% by moles, more preferably more than 75% by moles of recurring units derived from said at least one comonomer selected from those of formulae (a1) to (A3) above.

According to this first variant, polymer (F) preferably comprises up to 99% by moles, more preferably up to 95% by moles of recurring units derived from said at least one comonomer selected from those of formulae (a1) to (A3) above.

According to this first variant, polymer (F) preferably comprises from 77% by moles to 95% by moles of recurring units derived from said at least one comonomer selected from those having formulae (a1) to (A3) above and recurring units derived from TFE, so that the sum of the percentages of recurring units of said monomer and TFE equals 100% by moles.

According to a second variant of the first preferred embodiment, said at least one comonomer (F) is chosen in the group consisting of:

(C)CF₂＝CFOR_f1wherein R is_f1Selected from:

(R_f1*)-CF₃、-C₂F₅and-C₃F₇That is to say that,

perfluoromethyl vinyl ether (having the formula CF)₂＝CFOCF₃PMVE) of,

Perfluoroethyl vinyl ether (having the formula CF)₂＝CFOC₂F₅PEVE of (A),

Perfluoropropyl vinyl ether (having the formula CF)₂＝CFOC₃F₇PPVE) of (A), and

combinations thereof;

(R_f1**)-CF₂OR_f2，

wherein R is_f2Is straight-chain or branched C₁-C₆Perfluoroalkyl, cyclic C₅-C₆Perfluoroalkyl, straight-chain or branched C₂-C₆A perfluorooxyalkyl group; more preferably, R_f2is-CF₂CF₃(MOVE1)、-CF₂CF₂OCF₃(MOVE2)、-CF(CF₃)OCF₃(MOVE2a) or-CF₃(MOVE 3); and

-combinations thereof.

According to this second variant, polymer (F) preferably comprises more than 5% by moles, more preferably more than 15% by moles of recurring units derived from said at least one comonomer selected from those having formula (C).

According to this second variant, the polymer (F) preferably comprises up to 50% by moles, more preferably up to 45% by moles of recurring units derived from said at least one comonomer selected from those of formula (C) above.

According to this second variant, polymer (F) preferably comprises from 15% by moles to 45% by moles of recurring units derived from said at least one comonomer selected from those having formula (C) above and recurring units derived from TFE, so that the sum of the percentages of said recurring units of comonomer and TFE equals 100% by moles.

According to a second preferred embodiment, said polymer (F) is a homopolymer, i.e. it consists essentially of recurring units having the formula

(A1)

Wherein R is_f4、R_f5、R_f6Each, equal to or different from each other, is as defined above; more preferably, R_f4is-OCF₃Or F and R_f5And R_f6Both being fluorine atoms or both being formazanAnd (4) a base.

According to a third preferred embodiment, the polymer (F) is a homopolymer or a copolymer comprising recurring units having the formula:

(C**i)CF₂＝CFO-CF₂O-CF₂CF₃(MOVE1)；

(C**ii)CF₂＝CFO-CF₂O-CF₂CF₂OCF₃(MOVE2)；

(C**iii)CF₂＝CFO-CF₂O-CF(CF₃)OCF₃(MOVE2a)；

(C**iv)CF₂＝CFO-CF₂O-CF₃(MOVE3)；

and combinations thereof.

In the present invention, from the trade nameAD、

PFR-LT (both commercially available from Suweiter polymers, Italy),AF (commercially available from Kemu corporation) and

the selection of the polymer (F) from the polymers commercially available from cyanogen specialty industries, Inc. (Cytec Ind. Inc.) has yielded unexpected results.

Composition (C) can be prepared according to techniques known in the art. Preferably, the composition according to the invention is prepared by solvent mixing or dry mixing.

According to a first preferred embodiment, at least one polymer (F) is dissolved in at least one solvent [ solvent (S) ], preferably a (per) fluorinated solvent, and mixed with a blender machine.

The at least one solvent (S) is preferably chosen from those having a formula different from that of the polymer (P)(per) fluoropolyethers (e.g. from Suweiter polymers of Italy under the trade name Per @

Commercially available ones), perfluoroalkanes (e.g., perfluorohexane, perfluoroheptane, etc.), hydrofluoroethers, and mixtures thereof.

Then, the heating step is performed at a temperature lower than the boiling point of the solvent (S). More preferably, the heating step is carried out at a temperature between 20 ℃ and 100 ℃. Even more preferably, the heating step is carried out for at least 1 hour.

Then, a step of cooling to room temperature is carried out, thereby obtaining a composition [ composition (C) in the form of a solution comprising said polymer (F) and said at least one solvent (S)^∧]。

Then, the composition (C)^∧) With at least one polymer (P) to form a composition [ composition (C)^∧∧)]And a mixing step is performed. Preferably, the mixing step is performed at room temperature, more preferably for about 1 hour. Then, heating the composition (C)^∧∧) To remove said at least one solvent (S), preferably by treatment under vacuum, to obtain the composition (C) according to the invention.

According to a second preferred embodiment, the at least one polymer (P) and the at least one polymer (F) are first brought into contact and then mixed together with a stirrer machine. The heating step is then carried out at a temperature of about 150 ℃ to 200 ℃, preferably for more than 1 hour, even more preferably from 2 to 5 hours.

Preferably, the composition (C) comprises at least one polymer (P) in an amount of above 50 wt.% and up to 99.99 wt.%, more preferably from 60 wt.% to about 99.95 wt.%, even more preferably from 70 wt.% to 99.90 wt.%, based on the total weight of the composition (C).

Preferably, the composition (C) comprises at least one polymer (F) in an amount of from 0.01 to less than 50 wt.%, more preferably from 0.05 to 40 wt.%, even more preferably from 0.10 to 30 wt.%, based on the total weight of the composition (C).

According to a particularly preferred embodiment, the composition (C) comprises at least one polymer (F) in an amount of from 0.1 to 20 wt.%, based on the total weight of the composition (C).

Composition (C) according to the invention has a viscosity at 1rad/s measured at 20 ℃ according to standard methods (such as ASTM D445) or at from 100mm measured at 25 ℃ with an Anton Paar MCR 502 rheometer equipped with parallel plates 25mm²S to 2,000,000mm²Viscosity in the range of/s.

The composition (C) according to the present invention may further comprise additional ingredients selected from the group consisting of heat resistance improvers, antioxidants, anti-wear agents, and the like.

Typically, each of the additional ingredients is added to the composition in an amount of from 0.0001 wt.% and up to 5 wt.%, based on the total weight of composition (C).

Advantageously, the composition (C) according to the invention can be used as hydraulic fluid in viscous couplings, shock absorbers, pumps, brake cylinders; speed regulators, fluid clutches (e.g., for fans), marine and aeronautical instruments, gyroscopic compasses, shock-absorbing struts, recording instruments, time regulators, pneumatic valves, overload relays, damping media in pickups; a lubricant; and (3) a release agent.

According to a preferred embodiment, composition (C) is used as the working fluid in the viscous coupling.

A viscous coupler is a mechanical device typically composed of a housing, a hub, and several tens of annular thin plates attached to each of the housing and the hub. When the composition (C) according to the present invention is used, there is provided an adhesive coupler further comprising the composition (C) in a housing.

According to a preferred embodiment, the composition (C) is used as a working fluid in a damper device.

Suitable damper means are selected from the group consisting of: a buffer cylinder; shock absorbers, such as twin-tube or single-tube shock absorbers, Positive Sensitive Damping (PSD) shock absorbers, Acceleration Sensitive Damping (ASD); a rotary damper; a tuned mass damper; a viscous coupler; viscous fan clutches and torsional viscous dampers.

Typical devices in which the damper means may be used are selected from the group consisting of: mechanical or electrical devices for wheeled vehicles (e.g. suspension devices, gasifiers, internal combustion devices, engines, transmissions, crankshafts), for work vessels (e.g. engines), for aircraft and spacecraft (e.g. aircraft carrier decks), for power transmission lines, for wind turbines, for consumer electronics (e.g. mobile phones and personal computers), for offshore drilling, for oil and gas distribution systems (e.g. pumps); compressors (e.g., reciprocating compressors for gas piping); devices for buildings and civil structures (such as bridges, towers, elevated highways).

According to another embodiment, the invention relates to a method for increasing the viscosity of at least one polymer (P) as defined above, comprising contacting said at least one polymer (P) with at least one polymer (F) as defined above.

If the disclosure of any patent, patent application, and publication incorporated by reference herein conflicts with the description of the present application to the extent that terminology may become unclear, the description shall take precedence.

The invention will be explained in more detail below with the aid of examples contained in the experimental section below; these examples are merely illustrative and are in no way to be construed as limiting the scope of the invention.

Examples of the invention

Material

Base oils 1 to 3, polymers A to E and

HT55 perfluoropolyether polymers are available from Suweiter polymers, Italy.

Base oil (P1):

Y06 PFPE

a branched PFPE oil having the formula:

CF₃O-[(CF₂CF(CF₃)O)_m-(CF₂O)_n]-CF₃

wherein m/n is 40/1 and has an average molecular weight of about 1, 800 Da.

Base oil (P2):

YPL1500 PFPE

a branched PFPE oil having the formula:

CF₃O-[(CF₂CF(CF₃)O)_m-(CF₂O)_n]-CF₃

wherein m/n is 40/1 and has an average molecular weight of about 6,600 Da.

Base oil (P3):

PFPE

a branched PFPE oil having the formula:

CF₃O-[(CF₂CF(CF₃)O)_m-(CF₂O)_n]-CF₃

wherein m/n is 40/1 and has an average molecular weight of about 8,500 Da.

Polymer (F)^A)：

PFR LT

Low temperature perfluoroelastomers

Polymer (F)^B)：

AD 40L

Amorphous perfluorinated copolymers of 2, 2, 4-trifluoro-5-trifluoromethoxy-1, 3-dioxide (TTD) and Tetrafluoroethylene (TFE)

Having a glass transition temperature of 95 ℃ (measured according to ASTM D3418) and an intrinsic viscosity of 0.40dl/g at 30 ℃ (measured according to ASTM D2857).

Polymer (F)^C)：

AD 40H

Having a glass transition temperature of 95 ℃ (measured according to ASTM D3418) and an intrinsic viscosity of 1.3dl/g at 30 ℃ (measured according to ASTM D2857).

Polymer D:

L203

PTFE powder

Polymer E:

5000

PVDF powder

Method of producing a composite material

Kinematic viscosity at a given temperature was determined according to ASTM D445 using a Cannon-Fenske capillary viscometer.

Viscosity Index (VI) was determined according to ASTM D2270.

The compositions according to the invention were prepared according to the following procedure.

Polymers FA, F were weighed in the amounts provided in the following table^BAnd F^CAnd dissolving it in a solvent having 40g as solvent

HT55 glass flask. The mixture was left at 40 ℃ for one hour with stirring. At the end of the stirring, the mixture was analyzed by visual inspection. The solution was homogeneous.

Then, 98g of base oil P3 was added and the mixture was heated to reflux of the solvent for one hour with stirring (700 rpm). The thus obtained solution, which appeared clear and homogeneous, was heated up to 150 ℃ under vacuum in order to remove the solvent.

The final composition consisted of a single phase that was clear, viscous and tacky.

Such compositions were subjected to further characterization and analysis.

All compositions according to the invention were prepared following the procedure described above by using the base oils, polymers provided in table 1 below.

Table 1 also shows the properties of each base oil by way of comparison.

TABLE 1

Comparative

By way of further comparison, a composition comprising base oil (P3) and each of polymer D and polymer E was prepared following the same procedure described above for the composition according to the invention.

The composition thus obtained was analyzed by visual inspection and found to be completely milky white.

The composition thus obtained was centrifuged for about 5 minutes in order to improve its mixing. After this centrifugation, two phases appear showing separation between the solid polymer and the base oil.

Due to this phase separation, the kinematic viscosity cannot be measured and the viscosity index cannot be calculated.

Further analysis confirmed that both phases contained the original components.

Claims

1. A composition [ composition (C) ] comprising at least one (per) fluoropolyether polymer [ polymer (P) ] and at least one amorphous polymer [ polymer (F) ], wherein said composition (C) is in the form of a solution.

2. The composition according to claim 1, wherein the polymer (P) comprises a (per) fluoropolyether chain [ chain (R) having the formula_pf)]：

-(CFX)_aO(R_f)(CFX′)_b-

Wherein

(R_f) Comprising a repeating unit R^oPreferably consisting of, said repeating units are independently selected from the group consisting of:

(i) -CFXO-, wherein X is F or CF₃；

(iii)-(CF₂)_j-CFZ-O-, wherein j is an integer from 0 to 3 and Z is of the formula-O-R_(f-a)A group of-T, wherein R_(f-a)Is a fluoropolyoxyalkylene chain comprising a number of repeating units from 0 to 10, said repeating units being selected among: -CFXO-, -CF₂CFXO-, wherein each X is independently F or CF₃And T is C₁-C₃A perfluoroalkyl group.

3. The composition according to claim 2, wherein the chain (R)_f) Selected from chains having the formula:

(R_f-I)-[(CF₂CF₂O)_b1(CF₂O)_b2(CF(CF₃)O)_b3(CF₂CF(CF₃)O)_b4]-

wherein:

(R_f-II)-[(CF₂CF₂O)_c1(CF₂O)_c2(CF₂(CF₂)_cwCF₂O)_c3]-

wherein:

cw ═ 1 or 2;

(R_f-III)-[(CF₂CF(CF₃)O)_d]-

wherein:

(R_f-IV)-[(CF₂O)_c2(CF₂(CF₂)_cwCF₂O)_c3]-

wherein:

cw ═ 1 or 2;

(R_f-V)-[(CF₂CF₂C(Ha1*)₂O)_e1-(CF₂CF₂CH₂O)_e2-(CF₂CF₂CH(Ha1*)O)_e3]-

wherein:

-Ha1, equal or different at each occurrence, is a halogen selected from fluorine and chlorine atoms, preferably a fluorine atom;

4. The composition according to claim 3, wherein the chain (R)_f) Selected from the group consisting of compounds of the formula (R)_f-VI-a) to (R)_f-chain of VI-c):

(R_f-VI-a)-[(CF₂CF(CF₃)O)_f1-(CF₂O)_f2]-

wherein

(R_f-VI-b)-(CF(CF₃)CF₂O)_f3-

wherein

(R_f-VI-c)-(CF₂CF₂CF₂O)_f4-

wherein

5. Composition according to claim 1, wherein said polymer (F) is selected in the group consisting of amorphous polymers characterized by a glass transition temperature (T) in the range from-100 ℃ to 250 ℃, measured according to ASTM D3418_g)。

6. The composition according to claim 5, wherein the polymer (F) is selected from the group consisting of:

-styrene polymers and copolymers;

-vinyl polymers and copolymers;

-acrylic polymers and copolymers;

- (per) fluoropolymers;

-a polyester;

polyamide imides (PAI) and Polyetherimides (PEI);

-a polyether;

-a sulfur-containing polymer;

-polyurethanes (TPU), fluorinated polyurethanes and acrylonitrile polymers.

7. The composition according to claim 6, wherein the polymer (F) is a perfluoropolymer.

8. The composition according to claim 7, wherein the polymer (F) is a perfluoropolymer comprising recurring units derived from at least one perfluorinated monomer chosen in the group comprising:

(A1)

wherein R is_f4、R_f5、R_f6Each independently of the other, being the same or different from each other, is a fluorine atom, C₁-C₆A perfluoroalkyl group, optionally containing one or more oxygen atoms;

(A2)

wherein n is 1 or 2;

(A3)

wherein n is 1 or 2;

(C)CF₂＝CFOR_f1wherein R is_f1Selected from:

(R_f1*)C₁-C₆perfluoroalkyl group and

(R_f1**)-CF₂OR_f2

wherein

t is an integer equal to 1 or 2 and

R_f2is straight-chain or branched C₁-C₆Perfluoroalkyl, cyclic C₅-C₆Perfluoroalkyl, or a linear or branched C comprising one or more ether groups₁-C₁₂A perfluorooxyalkyl group.

9. The composition according to claim 8, wherein said polymer (F) comprises recurring units derived from Tetrafluoroethylene (TFE) and from at least one perfluorinated monomer [ comonomer (F) ] different from TFE.

10. The composition according to claim 9, wherein said at least one comonomer (F) is selected from the group consisting of:

(A1)

(A2)

wherein n is 1 or 2;

(A3)

wherein n is 1 or 2; and

-a combination thereof;

or selected from the group consisting of:

(C)CF₂＝CFOR_f1wherein R is_f1Selected from:

(R_f1*)-CF₃、-C₂F₅and-C₃F₇And combinations thereof;

(R_f1**)-CF₂OR_f2wherein R is_f2Is straight-chain or branched C₁-C₆Perfluoroalkyl, cyclic C₅-C₆Perfluoroalkyl, straight or branched C₂-C₆A perfluorooxyalkyl group; and

-combinations thereof.

11. The composition of claim 8, wherein the polymer (F) consists essentially of repeat units having the formula:

(A1)

wherein R is_f4、R_f5、R_f6Each, equal to or different from each other, is as defined above; more preferably, R_f4is-OCF₃Or F and R_f5And R_f6Both are fluorine atoms or both are methyl groups.

12. The composition of claim 8, wherein the polymer (F) comprises a repeat unit having the formula:

(D**i)CF₂＝CFO-CF₂O-CF₂CF₃(MOVE1)；

(D**ii)CF₂＝CFO-CF₂O-CF₂CF₂OCF₃(MOVE2)；

(D**iii)CF₂＝CFO-CF₂O-CF(CF₃)OCF₃(MOVE2a)；

(D**iv)CF₂＝CFO-CF₂O-CF₃(MOVE3)；

and combinations thereof.

13. Composition according to any one of the preceding claims, wherein the composition (C) comprises at least one polymer (P) in an amount higher than 50 wt.% and up to 99.99 wt.%, more preferably from 60 wt.% to about 99.95 wt.%, even more preferably from 70 wt.% to 99.90 wt.%, based on the total weight of the composition (C).

14. Composition according to any one of the preceding claims, wherein the composition (C) comprises at least one polymer (F) in an amount of from 0.01 to less than 50 wt.%, more preferably from 0.05 to 40 wt.%, even more preferably from 0.10 to 30 wt.%, based on the total weight of the composition (C).

15. Use of the composition (C) according to any one of claims 1 to 14 as a hydraulic fluid, a damping medium, a lubricant or a release agent.

16. A process for increasing the viscosity of at least one polymer (P) according to claims 3 and 4, comprising contacting said at least one polymer (P) with at least one polymer (F) as defined in any one of claims 5 to 12.