阅读说明：本技术 可固化含氟弹性体组合物 (Curable fluoroelastomer compositions ) 是由 朴志英 福士达夫 米格尔·A·格拉 凯坦·P·亚里瓦拉 克劳斯·辛策 于 2019-02-13 设计创作，主要内容包括：本发明公开了一种可固化组合物,其包含氟化无定形含氟聚合物和R<Sub>f</Sub>-[(CH<Sub>2</Sub>)<Sub>y</Sub>-OH]<Sub>x</Sub>的氟化多元醇交联剂,其中R<Sub>f</Sub>表示化合价x的全氟烷亚基基团,下标y为1或2；并且下标x为2至4。(A curable composition comprising a fluorinated amorphous fluoropolymer and R f ‑[(CH 2 ) y ‑OH] x Wherein R is f Represents a perfluoroalkylidene group of valence x, with subscript y being 1 or 2; and subscript x is 2 to 4.)

1. A curable composition comprising:

a partially fluorinated amorphous fluoropolymer having a high degree of fluorination,

optionally organic

an acid acceptor; and

a curing agent for a fluorinated polyol curing agent of the formula

R_f-[(CH₂)_y-O-(CH₂-CH(OH)-CH₂-O)_zH]_xWherein

R_fDenotes a perfluorinated group, including a perfluoroalkylidene group or perfluoroether group of valence x,

subscript y is 1 to 8;

subscript x is 2 to 4;

z is 0 or 1.

2. The curable composition of claim 1, wherein R_fIs C₂-C₆A perfluoroalkylene group.

3. The curable composition of claim 1, wherein R_fSelected from divalent-C_nF_2n ^-trivalent-C_nF_2n-1And tetravalent-C_nF_2n-2-, where n is 3 to 8.

4. The curable composition of claim 1, wherein the fluorinated polyol has the formula:

[R_f ¹³-O-R_f ¹⁴-(R_f ¹⁵)_q]-[(CH₂)_y-OH]_xwherein

[R_f ¹³-O-R_f ¹⁴-(R_f ¹⁵)_q]Having a structure derived from said R_f ¹³、R_f ¹⁴Or R_f ¹⁵A valence x obtained by extracting two or more F atoms from any one of the groups,

R_f ¹³represents a perfluoroalkylene group, and represents a perfluoroalkyl group,

R_f ¹⁴represents a perfluoroalkyleneoxy group and a perfluoroalkyleneoxy group,

R_f ¹⁵represents a perfluoroalkylene group and q is 0 or 1;

subscript y is 1 to 8; and is

Subscript x is 2 to 4.

5. The curable composition of claim 1, wherein the fluorinated polyol has the formula:

R_f-[(CH₂)_y-OH]_xII, wherein

R_fA perfluoroalkylene group or perfluoroether group having a valence x,

subscript y is 1 to 8; and is

Subscript x is 2 to 4.

6. The curable composition of claim 1 wherein the amorphous fluoropolymer is partially fluorinated.

7. The curable composition of any one of the preceding claims, wherein the amorphous fluoropolymer is derived from vinylidene fluoride.

8. The curable composition of any one of the preceding claims, wherein the fluoropolymer comprises at least one of carbon-carbon double bonds or units capable of forming carbon-carbon double bonds along the amorphous fluoropolymer chain.

9. The curable composition of any one of the preceding claims, wherein the amorphous fluoropolymer is a copolymer of: (i) hexafluoropropylene, tetrafluoroethylene, and vinylidene fluoride; (ii) hexafluoropropylene and vinylidene fluoride; (iii) vinylidene fluoride and perfluoromethyl vinyl ether; (iv) vinylidene fluoride, tetrafluoroethylene, and perfluoromethyl vinyl ether; (v) (vii) vinylidene fluoride, tetrafluoroethylene, and propylene, or (vi) ethylene, tetrafluoroethylene, and perfluoromethyl vinyl ether, and (vii) blends thereof.

10. The curable composition of any one of the preceding claims, wherein the fluoropolymer comprises: from 10 to 50 mol% of recurring units derived from tetrafluoroethylene; 15 to 40 mol% of recurring units derived from hexafluoropropylene; 25 to 59 mole% of recurring units derived from vinylidene fluoride; 1 to 20 mol% of recurring units derived from chlorotrifluoroethylene; and optionally e.one or more repeating units derived from a fluorinated monomer other than tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride, and chlorotrifluoroethylene.

11. The curable partially fluorinated polymer composition of any one of the preceding claims, wherein the partially fluorinated amorphous fluoropolymer comprises: (i) adjacent copolymerized units of VDF and HFP; (ii) (ii) copolymerized units of VDF and a fluorinated comonomer having an acidic hydrogen atom; (iii) copolymerized units of TFE and a fluorinated comonomer having an acidic hydrogen atom; and (iv) combinations thereof.

12. The curable partially fluorinated polymer composition of claim 8, wherein the fluorinated comonomer having an acidic hydrogen atom is selected from the group consisting of: trifluoroethylene; vinyl fluoride; 3,3, 3-trifluoropropene-1; pentafluoropropene; and 2,3,3, 3-tetrafluoropropene.

13. The curable partially fluorinated polymer composition of any one of the preceding claims, wherein the partially fluorinated amorphous fluoropolymer is derived from (i) vinylidene fluoride, tetrafluoroethylene, and propylene; (ii) vinylidene fluoride, tetrafluoroethylene, ethylene, and perfluoroalkyl vinyl ethers such as perfluoro (methyl vinyl ether); (iii) vinylidene fluoride and hexafluoropropylene; (iv) hexafluoropropylene, tetrafluoroethylene, and vinylidene fluoride; (v) hexafluoropropylene and vinylidene fluoride; (vi) vinylidene fluoride and perfluoroalkyl vinyl ethers; (vii) vinylidene fluoride, tetrafluoroethylene, and perfluoroalkyl vinyl ether; (viii) vinylidene fluoride, perfluoroalkyl vinyl ether, hydropentafluoroethylene and optionally tetrafluoroethylene; (ix) tetrafluoroethylene, propylene and 3,3, 3-trifluoropropene; (x) Tetrafluoroethylene and propylene; (xi) Ethylene, tetrafluoroethylene, and a perfluoroalkyl vinyl ether, and optionally 3,3, 3-trifluoropropene; (xii) Vinylidene fluoride, tetrafluoroethylene, and perfluoroalkyl allyl ether, (xiii) vinylidene fluoride, and perfluoroalkyl allyl ether; (xiv) Vinylidene fluoride, tetrafluoroethylene, and perfluoroalkylallylether; (xv) Vinylidene fluoride and perfluoroalkylallyl ethers; (xvi) Vinylidene fluoride, tetrafluoroethylene, and perfluoroalkylallylether; (xv) Vinylidene fluoride and perfluoroalkylallyl ethers; and (xvi) combinations thereof.

14. The curable composition of any one of the preceding claims, wherein the organic is

15. The curable composition according to any one of the preceding claims, further comprising a secondary crosslinking agent selected from the group consisting of polyol compounds, polythiol compounds, polyamine compounds, amidine compounds, bisaminophenol compounds, and oxime compounds.

16. A molded article comprising a cured composition of any one of claims 1-15.

17. A method of making a shaped article, the method comprising the steps of:

providing a curable composition according to any one of claims 1-15;

heating the composition to a temperature sufficient to cure the composition; and

recovering the shaped article.

Background

Fluoropolymers are a commercially important class of materials, including, for example, crosslinked and uncrosslinked fluorocarbon elastomers, as well as semi-crystalline or glassy fluorocarbon plastics.

Fluorocarbon elastomers, particularly copolymers of vinylidene fluoride with other ethylenically unsaturated halogenated and non-halogenated monomers (such as hexafluoropropylene), have particular utility in high temperature applications, such as seals, gaskets, and liners. See, e.g., r.a. bruulo, "fluoroelastomer rubbers for automotive applications", automotive elastomers and designs, 6 months 1985, "future of fluoroelastomer sealed automobiles", materials engineering, 10 months 1988, and w.m. glautat et al, "fluorocarbon elastomers," kork-Othmer (Kirk-Othmer), "encyclopedia of chemical technology", volume 8, page 990-once 1005 (4 th edition, John Wiley)&Sons 1993) (R.A. Brullo, "Fluoroelastomer Rubber for automatic applications," automatic Elastomer&Design,June 1985,“Fluoroelastomer Seal UpAutomotive Future,”Materials Engineering,October 1988,and W.M.Grootaert,etal.,“Fluorocarbon Elastomers,”Kirk-Othmer,Encyclopedia of ChemicalTechnology,Vol.8,pp.990-1005(4^thed.,John Wiley&Sons,1993))。

Disclosure of Invention

There is a need for new cure systems that identify partially fluorinated fluoropolymers. In one aspect, a curable partially fluorinated polymer composition is disclosed, comprising:

(i) partially fluorinated fluoropolymer, wherein the partially fluorinated amorphous fluoropolymer contains carbon-carbon double bonds or is capable of forming carbon-carbon double bonds along the partially fluorinated amorphous fluoropolymer; and

(ii) a curing agent comprising a fluorinated polyol compound (and salts thereof) of the formula:

R_f-[(CH₂)_y-O-(CH₂-CH(OH)-CH₂-O)_zH]_xi and conjugate bases thereof, wherein

R_fDenotes a perfluorinated group, including a perfluoroalkylidene group or perfluoroether group of valence x,

subscript y is 1 to 8;

subscript x is 2 to 4;

z is 0 or 1.

It is understood that the polyols of formula I include alkali metal salts, alkaline earth metal salts, and other salts thereof. Such salts may be prepared as described in US5681881 (sting et al), which is incorporated herein by reference.

In another aspect, an article comprising the cured composition described above is disclosed.

In yet another aspect, a method of making a partially fluorinated elastomer is disclosed that includes curing the curable partially fluorinated polymer composition disclosed above.

As used herein, "alkyl" and "alkylidene" refer to the monovalent and divalent residues remaining after removal of one and two hydrogen atoms, respectively, from a straight or branched chain hydrocarbon having from 1 to 20 carbon atoms. Examples of "alkyl" as used herein include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, n-pentyl, isobutyl, tert-butyl, isopropyl, n-octyl, n-heptyl, ethylhexyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, and the like. Unless otherwise specified, an alkyl group can be monovalent or polyvalent.

"fluorinated" refers to hydrocarbon compounds having one or more C-H bonds substituted with C-F bonds;

"fluoroalkyl" has essentially the same meaning as "alkyl," except that one or more of the hydrogen atoms of the alkyl group are replaced with fluorine atoms.

"fluoroalkylene" has essentially the same meaning as "alkylene," except that one or more of the hydrogen atoms of the alkyl group are replaced with fluorine atoms.

"perfluoroalkyl" essentially has the same meaning as "alkyl" except that all or substantially all of the hydrogen atoms of the alkyl group have been replaced with fluorine atoms, e.g., perfluoropropyl, perfluorobutyl, perfluorooctyl, and the like.

"perfluoroalkylene" has essentially the same meaning as "alkylene," except that all or substantially all of the hydrogen atoms of the alkylene group are replaced with fluorine atoms, e.g., perfluoropropylene, perfluorobutylene, perfluorooctylene, and the like.

Detailed Description

In the present disclosure, it has been found that partially fluorinated fluoropolymers can be cured with fluorinated polyol compounds of formula I and their conjugate bases.

The fluoropolymers of the present disclosure are partially fluorinated polymers. As disclosed herein, an amorphous partially fluorinated polymer is a polymer comprising at least one carbon-hydrogen bond and at least one carbon-fluorine bond in the polymer backbone. In one embodiment, the partially fluorinated polymer is highly fluorinated wherein at least 60%, 70%, 80% or even 90% of the polymer backbone comprises C-F bonds.

The fluoropolymers of the present disclosure also contain carbon-carbon double bonds and/or are capable of forming carbon-carbon double bonds along the polymer chain. In one embodiment, the partially fluorinated fluoropolymer contains carbon-carbon double bonds along the backbone of the partially fluorinated fluoropolymer or is capable of forming carbon-carbon double bonds along the backbone of the partially fluorinated fluoropolymer. In another embodiment, the partially fluorinated fluoropolymer contains carbon-carbon double bonds, or is capable of forming carbon-carbon double bonds in pendant groups other than the backbone of the partially fluorinated fluoropolymer.

The fluoropolymer being capable of forming carbon-carbon double bonds means that the fluoropolymer comprises units capable of forming double bonds. Such units include, for example, two adjacent carbons along the polymer backbone or pendant side chain, where a hydrogen is attached to the first carbon and a leaving group is attached to the second carbon. During the elimination reaction (e.g., thermal reaction and/or use of an acid or base), the leaving group and hydrogen leave, forming a double bond between the two carbon atoms. Exemplary leaving groups include: fluoride, alkoxide, hydroxide, tosylate, methanesulfonic acid, amine, ammonium, sulfide, sulfonium, sulfoxide, sulfone, and combinations thereof. Those fluoropolymers capable of forming carbon-carbon bonds typically have a structure of-CH-CX-wherein X is a leaving group such that when treated with a base, the desired degree of unsaturation will be provided. In many embodiments, the polymer has a-CH-CF-in the backbone, which can be dehydrofluorinated.

The fluoropolymer contains a plurality of these groups (carbon-carbon double bonds or groups capable of forming double bonds) to achieve sufficient cure. Typically, this means at least 0.1 mol%, 0.5 mol%, 1 mol%, 2 mol% or even 5 mol%; up to 7 mol%, 10 mol%, 15 mol% or even 20 mol% (i.e. the number of moles of these carbon-carbon double bonds or precursors thereof per mole of polymer).

In one embodiment, the amorphous partially fluorinated polymer is derived from at least one hydrogen-containing monomer, such as vinylidene fluoride.

In one embodiment, the amorphous fluoropolymer comprises: adjacent copolymerized units of vinylidene fluoride (VDF) and Hexafluoropropylene (HFP); copolymerized units of VDF (or tetrafluoroethylene) and a fluorinated comonomer capable of delivering acidic hydrogen atoms to the polymer backbone, such as trifluoroethylene; vinyl fluoride; 3,3, 3-trifluoropropene-1; pentafluoropropenes (e.g., 2-hydropentafluoropropene and 1-hydropentafluoropropene); 2,3,3, 3-tetrafluoropropene; and combinations thereof.

In some embodiments, a small amount (e.g., less than 10, 5,2, or even 1 weight percent) of additional monomer may be added, so long as the amorphous fluoropolymer is capable of being cured using the curing agent disclosed herein.

In one embodiment, the amorphous fluoropolymer is additionally derived from hydrogen-containing monomers comprising: pentafluoropropene (e.g., 2-hydrogenated pentafluoropropene), propylene, ethylene, isobutylene, and combinations thereof.

In one embodiment, the amorphous fluoropolymer is additionally derived from a perfluorinated monomer. Exemplary perfluorinated monomers include: hexafluoropropylene; tetrafluoroethylene; chlorotrifluoroethylene; perfluoro (alkyl vinyl ether), such as perfluoromethyl vinyl ether, CF₂＝CFOCFCF₂CF₂OCF₃、CF₂＝CFOCF₂OCF₂CF₂CF₃、CF₂＝CFOCF₂OCF₂CF₃、CF₂＝CFOCF₂OCF₃And CF₂＝CFOCF₂OC₃F₇Perfluoro (alkylallyl ether) such as perfluoromethylallyl ether, perfluoro (alkoxyallyl ether) such as perfluoro-4, 8-dioxa-1-nonene (i.e., CF)₂＝CFCF₂O(CF₂)₃OCF₃) (ii) a And combinations thereof.

Exemplary types of polymers include those comprising interpolymerized units derived from: (i) vinylidene fluoride, tetrafluoroethylene, and propylene; (ii) vinylidene fluoride, tetrafluoroethylene, ethylene, and perfluoroalkyl vinyl ethers such as perfluoro (methyl vinyl ether); (iii) vinylidene fluoride and hexafluoropropylene; (iv) hexafluoropropylene, tetrafluoroethylene, and vinylidene fluoride; (v) hexafluoropropylene and vinylidene fluoride, (vi) vinylidene fluoride and perfluoroalkyl vinyl ethers; (vii) (viii) vinylidene fluoride, tetrafluoroethylene, and perfluoroalkyl vinyl ether, (viii) vinylidene fluoride, perfluoroalkyl vinyl ether, hydropentafluoroethylene, and optionally tetrafluoroethylene; (ix) tetrafluoroethylene, propylene and 3,3, 3-trifluoropropene; (x) Tetrafluoroethylene and propylene; (xi) Ethylene, tetrafluoroethylene, and a perfluoroalkyl vinyl ether, and optionally 3,3, 3-trifluoropropene; (xii) Vinylidene fluoride, tetrafluoroethylene, and perfluoroalkyl allyl ether, (xiii) vinylidene fluoride, and perfluoroalkyl allyl ether; (xiv) Ethylene, tetrafluoroethylene, and a perfluoroalkyl vinyl ether, and optionally 3,3, 3-trifluoropropene; (xv) (xvi) vinylidene fluoride, tetrafluoroethylene, and perfluoroalkyl allyl ether, (xvi) vinylidene fluoride, and perfluoroalkyl allyl ether; (xvii) Vinylidene fluoride, tetrafluoroethylene, and perfluoroalkylallyl ether, (xviii) vinylidene fluoride, and perfluoroalkylallyl ether; (xiv) Vinylidene fluoride, tetrafluoroethylene, and perfluoroalkylallyl ether, (xv) vinylidene fluoride, and perfluoroalkylallyl ether; and (xvi) combinations thereof.

Advantageously, by using the curing agents disclosed herein, the amorphous fluoropolymers of the present disclosure can be cured without the need for side bromine, iodine, or nitrile cure sites along the polymer backbone. In general, iodine and bromine containing cure site monomers that polymerize to fluoropolymers and/or chain ends can be quite expensive.

The amorphous fluoropolymers of the present disclosure are substantially free of iodine, bromine, and nitrile groups, wherein the amorphous fluoropolymer comprises less than 0.1, 0.05, 0.01, or even 0.005 mole%, relative to the total polymer.

In one embodiment, the amorphous fluoropolymer of the present disclosure is a non-grafted polymer, that is, it does not contain pendant groups including vinyl, allyl, acrylate, amido, sulfonate, pyridine, carboxylate, sterically hindered silanes (which are aliphatic or aromatic tri-ethers or triesters). In one embodiment, the amorphous fluoropolymer does not contain monophenol grafts.

The amorphous fluoropolymers described above may be blended with one or more additional crystalline fluoropolymers. Using the curing compounds of the present invention, crystalline fluoropolymers can be cured into amorphous fluoropolymer matrices

Commercially available crystalline fluoropolymers include those fluoropolymers such as: such as those sold under the trade name "THV" (e.g., "THV 200", "THV 400", "THVG", "THV 610" or "THV 800") by tylane corporation of st paul, Minn, minnesota; "KYNAR" (e.g., "KYNAR 740") sold by Atofina, Philadelphia, Pa.); "HYLAR" (e.g., "HYLAR 700") sold by Ausimont of Morisdun, N.J.); and "FLUOREL" sold by Taihang corporation (e.g., "FLUOREL FC-2178").

Useful fluoropolymers also include copolymers of HFP, TFE, and VDF (i.e., THV). These polymers can have, for example, in the range of at least about 2 wt%, 10 wt%, or 20 wt% up to 30 wt%, 40 wt%, or even 50 wt% VDF monomeric units, and in the range of at least about 5 wt%, 10 wt%, or 15 wt% up to about 20 wt%, 25 wt%, or even 30 wt% HFP monomeric units, with the remaining weight of the polymer being TFE monomeric units. Examples of commercially available THV polymers include those sold by tylan under the trade names "dynamics THV 2030 gfluoroto chemiptitic", "dynamics THV 220 fluor chemiptitic", "dynamics THV 340 cfluoroto chemiptitic", "dynamics THV 415 fluor chemiptitic", "dynamics THV 500 afluoracousthelioptitic", "dynamics THV 610G fluor chemiptitic" or "dynamics THV 810 gfluorotohermitiatic".

Useful fluoropolymers also include copolymers of ethylene, TFE and HFP. These polymers can have, for example, in the range of at least about 2 wt%, 10 wt%, or 20 wt% up to 30 wt%, 40 wt%, or even 50 wt% ethylene monomer units, and in the range of at least about 5 wt%, 10 wt%, or 15 wt% up to about 20 wt%, 25 wt%, or even 30 wt% HFP monomer units, with the remaining weight of the polymer being TFE monomer units. Such polymers are sold by the company Tyron, for example under the trade name "DYNEON FLUOROTHERMOPLASTIC HTE" (e.g., "DYNEON FLUOROTHERMOPLASTIC HTE X1510" or "DYNEON FLUOROTHERMOPLASTIC HTE X1705").

Useful fluoropolymers also include copolymers of tetrafluoroethylene and propylene (TFE/P). These polymers can have, for example, in the range of at least about 20, 30, or 40 to at most about 50, 65, or even 80 weight percent TFE monomer units, with the remaining weight of the polymer being propylene monomer units. Such polymers are commercially available, for example, from tai, under the trade designation "AFLAS" (e.g., "AFLAS TFE ELASTOMER FA 100H", "AFLAS TFEELASTOMER FA 150C", "AFLAS TFE ELASTOMER FA 150L", or "AFLAS TFE ELASTOMER FA 150P"), or from e.i. dupont de Nemours & Company, Wilmington, Del, wil., wilton, dalton, dela, e.g., "VITON VTR-7480" or "VITON VTR-7512".

Useful fluoropolymers also include copolymers of ethylene and TFE (i.e., "ETFE"). These polymers can have, for example, in the range of at least about 20, 30, or 40 to at most about 50, 65, or even 80 weight percent TFE monomer units, with the remaining weight of the polymer being propylene monomer units. Such polymers are commercially available, for example, from Thailand under the trade names "DYNEON FLUOROTHERMOPLASTIC ET 6210J", "DYNEON LUOROTHERMOPLASTIC ET 6235" or "DYNEON FLUOROTHERMOPLASTIC ET 6240J".

VDF-containing fluoropolymers may be prepared using emulsion polymerization techniques as described, for example, in US 4,338,237(Sulzbach et al) or US5,285,002 (Grooinert), the disclosures of which are incorporated herein by reference.

The curable composition also includes a fluorinated polyol curing agent of the formula:

R_f-[(CH₂)_y-O-(CH₂-CH(OH)-CH₂-O)_zH]_xi (and conjugate bases thereof), wherein

R_fA perfluoroalkylene group or perfluoroether group having a valence x,

subscript y is 1 to 8;

subscript x is 2 to 4;

z is 0 or 1.

It is understood that formula I includes compounds of the formula:

R_f-[(CH₂)_y-OH]_xII, wherein

R_fA perfluoroalkylene group or perfluoroether group having a valence x,

subscript y is 1 or 2;

and is

Subscript x is 2 to 4.

R_fThe groups may comprise linear, branched, or cyclic multivalent perfluorinated groups in any combination and have the general formula:

for divalent radicals is-C_nF_2n ^-For the trivalent radical-C_nF_2n-1-for tetravalent radicals-C_nF_2n-2-and the like. A divalent group in which n-3 to 8 is more preferable, and a divalent group in which n-2 to 5 is most preferable. The compounds of formula I will include the corresponding salts or conjugate bases.

Minute amount of hydrogenOr a chlorine atom may also be present as a substituent, provided that there is no more than one atom for every two carbon atoms. Preferably R_fThe groups are fully perfluorinated.

The perfluoroalkylene group can contain 1 to 10 carbon atoms, preferably 2 to 6 carbon atoms. A typical divalent perfluoroalkylene group is-CF₂-CF₂-、-CF₂-CF₂-CF₂-、-CF(CF₃)-CF₂-、-CF₂-、-CF₂-CF₂-CF₂-CF₂-CF₂-CF₂-, cyclic C₆F₁₂-or-CF (CF)₃)-。

In some embodiments, R_fThe groups may be selected from perfluoroether groups:

[R_f ¹³-O-R_f ¹⁴-(R_f ¹⁵)_q]-[(CH₂)_y-OH]_xIV, wherein

[R_f ¹³-O-R_f ¹⁴-(R_f ¹⁵)_q]Having a structure from R_f ¹³、R_f ¹⁴Or R_f ¹⁵A valence x obtained by extracting two or more F atoms from any one of the groups,

R_f ¹³represents a perfluoroalkylene group, and represents a perfluoroalkyl group,

R_f ¹⁴represents a perfluoroalkyleneoxy group and a perfluoroalkyleneoxy group,

R_f ¹⁵represents a perfluoroalkylene group and q is 0 or 1

Subscript y is 1 to 8; and is

Subscript x is 2 to 4.

The corresponding carboxylic acid derivative R is reacted with sodium borohydride or lithium aluminum hydride using standard techniques_f-(COX)_x(wherein X is halide, OH OR, wherein R ═ methyl OR ethyl, and subscript X is 2 to 8) to obtain the perfluorinated polyol of formula I wherein subscript y ═ 1. Perfluorinated alcohols of the formula VIII in which y-2 can be reacted with ethylene from the corresponding iodide and then hydrolyzed to the so-called telomer alcoholsThus obtaining the product. This method is described in US 5491261(Haniff et al), which is incorporated herein by reference. The higher idomrsd can be prepared by reacting a perfluoroiodo compound with an unsaturated alcohol, followed by reduction of the iodine adduct:

R_f-I+CH₂＝CH-(CH₂)_y-2-OH→

in some embodiments, the fluorinated polyol may be the reaction product of a polyol of formula II:

R_f-[(CH₂)_y-OH]_x+X-CH₂-epoxy → R_f-[(CH₂)_y-O-CH₂-CH(OH)-CH₂OH]_x，III

Wherein X is a leaving group such as halide or tosylate. It is to be understood that the perfluoroether compound of formula IV can be reacted with the glycidyl compound in a similar manner as shown for III.

The amount of curing agent used should be sufficient to cause the amorphous fluoropolymer to cure as indicated by the increase in torque on the rotorless rheometer. For example, at least 0.5 parts to 20 parts of crosslinking agent per 100 parts of amorphous fluoropolymer is used. If too little curative is used, the amorphous fluoropolymer will not cure. If too much curative is used, the amorphous fluoropolymer may become brittle. For example, no more than 20 millimoles of curative are used per 100 parts of amorphous fluoropolymer. One or a blend of polyol compounds having formula I may be used.

In addition to the polyol curing agent of formula I, the curable composition may optionally include a second optional crosslinker. Examples of the optional crosslinking agent include polyol compounds, polythiol compounds, polyamine compounds, amidine compounds, bisaminophenol compounds, oxime compounds, and the like. In some embodiments, the second crosslinker may comprise a non-fluorinated hydrocarbyl polyol similar to formula I.

In general, depending on the type of polymer, examples are not limited to the selection of a specific combination of sulfonamide of formula I with secondary crosslinker and/or crosslinking facilitator, but typical examples are shown below. For example, for vinylidene fluoride systems (binary systems or ternary systems), polyol compounds, polyamine compounds, polythiophene compounds are preferable. For the tetrafluoroethylene-propylene-vinylidene fluoride-based fluororubber (ternary) system, a polyol compound, a polyamine compound, a polythiol compound, or the like is preferable.

Examples of preferred polyol compounds include 2, 2-bis (4-hydroxyphenyl) hexafluoropropane, 4 '-dihydroxydiphenylsulfone, 4' -diisopropylidenediphenol, and the like.

Examples of preferred polythiol compounds include 2-dibutylamino-4, 6-dimercapto-s-triazine, 2,4, 6-trimercapto-s-triazine, and the like.

Examples of preferred polyamine compounds include hexamethylene diamine carbamate, N '-diphenylene allyl-1, 6-hexamethylene diamine, 4' -methylene bis (cyclohexylamine) carbonate, and the like.

Examples of preferred amidine compounds include p-toluenesulfonate salt of 1, 8-diazabicyclo [5.4.0] undec-7-ene, and the like.

Examples of preferred bisaminophenol compounds include 2, 2-bis (3-amino-4-hydroxyphenyl)) -hexafluoropropane, 2-bis [ 3-amino-4- (N-phenylamino) phenyl ] hexafluoropropane and the like.

In some embodiments, the combination of polyols of formula I may be with a compound of formula Z-Q-R_f-O-(R_fo)R_f-Q-Z, as described in US 5384374 and US 5266650(Guerra et al), each of which is incorporated herein by reference.

If an optional second crosslinker is used, the molar ratio of the polyol curative of formula I to the second crosslinker can be from 5:1 to 1: 1.

The curable composition may further comprise an acid acceptor comprising an organic acid acceptor, an inorganic acid acceptor, or a blend thereof. Examples of inorganic acceptors include magnesium oxide, lead oxide, calcium hydroxide, dibasic lead phosphate, zinc oxide, barium carbonate, strontium hydroxide, calcium carbonate, hydrotalcite, and the like. Organic acceptors include amines, epoxides, sodium stearate, and magnesium oxalate. Particularly suitable acid acceptors include calcium hydroxide, magnesium oxide, and zinc oxide. Blends of acid acceptors may also be used. The amount of acid acceptor will generally depend on the nature of the acid acceptor used.

If the presence of extractable metal compounds is not desired (such as in semiconductor applications), the use of inorganic acid acceptors should be minimized, and preferably these should not be used at all. For example, the hardening composition having a formulation that does not use an inorganic acid acceptor is particularly useful for a sealing material and gasket for manufacturing semiconductor elements, a sealing material that comes into contact with water, hot water, or the like, and a sealing material for high-temperature areas such as automotive applications.

Examples of preferred acid acceptors commonly used include zinc oxide, calcium hydroxide, calcium carbonate, magnesium oxide, hydrotalcite, silicon dioxide (silica), lead oxide, and the like. These compounds are generally used in order to bond to HF and other acids. These acids may be generated at high temperatures encountered during hardening when molding a molded article using the fluoropolymer composition, or at temperatures at which the function of the fluoropolymer, etc., is exhibited.

In one embodiment, at least 0.5 parts, 1 part, 2 parts, 3 parts, or even 4 parts of acid acceptor is used per 100 parts of amorphous fluoropolymer. In one embodiment, no more than 10, 7, or even 5 parts of acid acceptor are used per 100 parts of amorphous fluoropolymer.

The curable composition may also contain an organic compoundCompound, organic

The compounds are added to the composition as phase transfer catalysts to assist in crosslinking the amorphous fluoropolymer and/or may be used to generate double bonds on the fluoropolymer by dehydrofluorination. Such organic compoundsThe compound comprises quaternary ammonium hydroxide or salt thereof, quaternary phosphoniumHydroxides or salts thereof and ternary sulfonium hydroxides or salts thereof.

In short,and ammonium salts or compounds containing a central atom of phosphorus or nitrogen, respectively, covalently bonded to the four organic moieties by way of a carbon-phosphorus (or carbon-nitrogen) covalent bond and associated with an anion. The organic moieties may be the same or different.

Briefly, sulfonium compounds are sulfur-containing organic compounds in which at least one sulfur atom is covalently bonded by means of a carbon-sulfur covalent bond to three organic moieties having from 1 to 20 carbon atoms and associated with an anion. The organic moieties may be the same or different. The sulfonium compounds may have more than one relatively positive sulfur atom, e.g., [ (C)₆H₅)₂S⁺(CH₂)₄S⁺(C₆H₅)₂]₂Cl^-And the two carbon-sulfur covalent bonds may be between carbon atoms of the divalent organic moiety, that is, the sulfur atom may be a heteroatom in a cyclic structure.

A number of organic compounds useful in the present invention are describedCompounds and are known in the art. See, for example, U.S. Pat. No.4,233,421 (work), U.S. Pat. No.4,912,171(Grootaert et al), U.S. Pat. No.5,086,123(Guenthner et al), and U.S. Pat. No.5,262,490(Kolb et al), U.S. Pat. No.5,929,169, the descriptions of which are incorporated herein by reference. Another useful class of organic compounds

Compounds include those having one or more pendant fluorinated alkyl groups. Generally, the most useful fluorination

The compounds are disclosed by Coggio et al in U.S. Pat. No.5,591,804.

Exemplary organic CompoundsThe compound comprises: c₃-C₆Symmetric tetraalkylammonium salts, asymmetric tetraalkylammonium salts, wherein the total number of alkyl carbons is between 8 and 24; and benzyltrialkylammonium salts in which the total number of alkyl carbons is between 7 and 19, (e.g., tetrabutylammonium bromide, tetrabutylammonium chloride, benzyltributylammonium chloride, benzyltriethylammonium chloride, tetrabutylammonium hydrogen sulfate, and tetrabutylammonium hydroxide, phenyltrimethylammonium chloride, tetrapentylammonium chloride, tetrapropylammonium bromide, tetrahexylammonium chloride, and tetraheptylammonium tetramethylammonium bromide); season

Salts, such as tetrabutylSalt, tetraphenyl chloride

Benzyl triphenyl chlorideTributylallyl chloride

Tributylbenzyl chlorideTributyl-2-methoxypropyl Chlorination

Benzyldiphenyl (dimethylamino) chloride

8-benzyl-1, 8-diazobicyclo [ 5.4.0%]7-undecene

Chloride, benzyl tris (dimethylamino) chlorideAnd bis (benzyldiphenylphosphine) iminium chloride. Other suitable organic compoundsThe compound comprises 1, 8-diazabicyclo [5.4.0]Undec-7-ene and 1, 5-diazabicyclo [4.3.0]Non-5-ene. Phenates being quaternary ammonium salts and quaternary phosphonium salts

Preferred anions of the salts.

In one embodiment, organic

The compound is used in an amount between 1 and 5 millimoles (mmhr) per 100 parts of amorphous fluoropolymer.

In addition to the above components, the fluoropolymer composition may also contain various additives. Examples of the additives include a crosslinking aid and/or a crosslinking promoting aid which are favorably combined with a crosslinking agent and/or a crosslinking promoter used, a filler such as carbon black, spangle, silica, diatomaceous earth, a silicate compound (clay, talc, wollastonite, etc.), calcium carbonate, titanium oxide, precipitated barium sulfate, alumina, mica, iron oxide, chromium oxide, a fluoropolymer filler, etc., a plasticizer, a lubricant (graphite, molybdenum disulfide, etc.), a mold release agent (fatty acid ester, fatty acid amide, fatty acid metal, low molecular weight polyethylene, etc.), a coloring agent (cyanine green, etc.), and a processing aid which is commonly used when compounding a fluoropolymer composition, and the like. However, these additives are preferably sufficiently stable under the intended use conditions.

In addition, carbon black can be used to achieve a balance between fluoropolymer composition properties such as tensile stress, tensile strength, elongation, hardness, abrasion resistance, conductivity, processability, and the like. Preferred examples include MT carbon blacks (medium thermal blacks) with product numbers N-991, N-990, N-908 and N-907; FEF N-550; and large diameter furnace black, etc. If carbon black is used, the amount is preferably about 0.1 parts by mass to about 70 parts by mass (phr), based on 100 parts by mass of the total amount of the polymer containing a fluorinated olefin unit and the additional polymer. This range is particularly preferred for the case where large particle furnace black is used.

The curable amorphous fluoropolymer composition may be prepared as follows: the amorphous fluoropolymer, curative, along with other components (e.g., acid acceptor, hardener, plasticizer, etc.) are mixed in conventional rubber processing equipment,

Compound and/or additional additives) to provide a solid mixture, i.e., a solid polymer comprising additional ingredients, also referred to in the art as a "compound. This method of mixing ingredients to produce such solid polymer compositions comprising other ingredients is commonly referred to as "compounding". Such equipment includes rubber mills, internal mixers (e.g., banbury mixers), and mixing extruders. The temperature of the mixture during mixing typically does not rise above about 120 c. During mixing, the components and additives are uniformly distributed throughout the resulting fluorinated polymer "compound" or polymer sheet. The "compound" may then be extruded or pressed into a mold (e.g., a cavity or transfer mold) and subsequently oven cured. In an alternative embodiment, curing may be carried out in an autoclave.

Curing is typically accomplished by heat treating the curable amorphous fluoropolymer composition. Heat treatment is conducted at an effective temperature and for an effective time to produce a cured fluoroelastomer. The optimum conditions can be tested by examining the mechanical and physical properties of the cured fluoroelastomer. Curing is typically carried out at a temperature greater than 120 ℃ or greater than 150 ℃. Typical curing conditions include curing at a temperature between 160 ℃ and 210 ℃ or between 160 ℃ and 190 ℃. Typical cure cycles include 3 to 90 minutes. Curing is preferably carried out under pressure. For example, a pressure of 10 bar to 100 bar may be applied. A post cure cycle may be applied to ensure that the curing process is fully completed. The post-curing may be carried out at a temperature between 170 ℃ and 250 ℃ for a time of 1 to 24 hours.

The partially fluorinated amorphous fluoropolymer in the curable composition has a mooney viscosity determined according to ASTM D1646-06 type a by MV 2000 instrument (available from alpha technologies, Ohio, USA) using a large rotor (ML 1+10) at 121 ℃. Upon curing, using the curatives disclosed herein, the amorphous fluoropolymer becomes an elastomer, becomes a nonflowable fluoropolymer, and has an infinite viscosity (and thus no measurable mooney viscosity).

The above curable compositions may be compounded or mixed in one or more steps, and the mixture may then be processed and shaped, for example, by extrusion (e.g., in the form of a hose or hose liner) or molding (e.g., in the form of an O-ring). The shaped article can then be heated to cure the composition and form a cured elastomeric article.

In some embodiments, the desired amounts of conventional additive adjuvants or ingredients can be added to the uncured composition and intimately blended or compounded by employing any of the usual rubber mixing devices such as a banbury mixer, roll mill, or any other convenient mixing device. The temperature of the mixture on the mill does not typically rise above about 120 c. During milling, the components and adjuvants are uniformly distributed throughout the gum. The curing process typically includes extruding or pressing the compounded mixture into a mold (e.g., a cavity or transfer mold), and subsequent oven curing. The compounded mixture is typically pressed (press cured) at a temperature of from about 95 ℃ to about 230 ℃, preferably from about 150 ℃ to about 205 ℃, for a period of from 1 minute to 15 hours, typically from 5 minutes to 30 minutes. Typically, a pressure of between about 700kPa and about 20,600kPa is applied to the compounded mixture in the mold. The mold may first be coated with a release agent such as silicone oil and pre-baked. The molded vulcanizate is then post-cured (oven cured) typically at a temperature typically between about 150 ℃ and about 315 ℃ for a period of time from about 2 hours to 50 hours or more, depending on the cross-sectional thickness of the article.

The compositions of the present invention are useful in forming seals, O-rings, and gaskets. The cured fluorocarbon elastomer mixture has excellent low temperature flexibility while maintaining the desired physical properties, such as tensile strength and elongation, of conventionally compounded and cured compositions. Particularly useful articles that can be made from the fluorocarbon elastomer compositions of the present invention are particularly useful as seals, gaskets, and mold parts in automotive, chemical processing, semiconductor, aerospace, and petroleum industry applications, among others.