Process for preparation of fluorosilicon polymer

1. A process for producing a crosslinked fluorinated polymer comprising the steps of:

A) providing an iodinated oligomer consisting essentially of:

1) 40 to 90 mole percent copolymerized units of a first monomer selected from the group consisting of vinylidene fluoride and tetrafluoroethylene;

2) 10 to 60 mole percent copolymerized units of a second monomer of the formula CF 2 ═CFOR f where R f is a perfluoroalkylene group of 1-5 carbon atoms;

3) 0 to 10 mole percent copolymerized units of a comonomer selected from the group consisting of hexafluoropropylene and tetrafluoroethylene, with the proviso that said comonomer can only be tetrafluoroethylene when said first monomer is vinylidene fluoride and said comonomer can only be hexafluoropropylene when said first monomer is tetrafluoroethylene;

4) 0 to 10 mole percent copolymerized units of a perfluoro(vinyl ether) of formula CF 2 ═CFO(R f′ O) n (R f″ O) m R f , where R f′ and R f″ are different linear or branched perfluoroalkylene groups of 2-6 carbon atoms, m and n are independently 0-10, and R f is a perfluoroalkyl group of 1-6 carbon atoms, with the proviso that said perfluoro(vinyl ether) is different from said second monomer; and

5) 0 to 10 mole percent copolymerized units of a functional fluorovinyl ether selected from the group consisting of a functional fluorovinyl ether selected from the group consisting of

a) propanoic acid, 3-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-, methyl ester;

b) ethanesulfonyl fluoride, 2-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-1,1,2,2-tetrafluoro-;

c) 1-propanol, 3-[1-[difluoro[(trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-;

d) propanenitrile, 3-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-;

e) hexanenitrile, 2,2,3,3,4,4,5,5,6,6-decafluoro-6-[(1,2,2-trifluoroethenyl)oxy]-;

f) propanenitrile, 2,3,3,3-tetrafluoro-2-[1,1,2,2,3,3-hexafluoro-3-[(trifluoroethenyl)oxy]propoxy]-;

g) propanamide, 3-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-;

h) 1-propanol, 3-[1-[difluoro[(trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-, dihydrogen phosphate; and

i) propanoic acid, 3-[1-[difluoro[(trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-

wherein said diiodinated oligomer has a number average molecular weight of 1000 to 25,000 g/mole and wherein said oligomer has an iodine group at each chain end;

B) contacting said iodinated oligomer with a vinyl silane of the formula

CH 2 ═CY—(CH 2 ) n —SiRR′R″

where Y is a hydrogen atom or a C 1 -C 3 alkyl group, R is a methoxy or ethoxy group, and R′ and R″ are independently selected from the group consisting of methyl groups, methoxy groups and ethoxy groups, under conditions wherein the molar ratio to form a silicon-containing polymeric adduct that is a composition of the formula

PC—[CH 2 CYI—(CH 2 ) n SiRR′R″] m

where PC is the polymer chain of said iodinated oligomer, n is 0-2 and m is 2; and

C) contacting said silicon-containing polymeric adduct with an acid to form a crosslinked fluorinated polymer.

2. A process of claim 1 wherein the first monomer is vinylidene fluoride.

3. A process of claim 1 wherein the first monomer is tetrafluoroethylene.

4. A process of claim 1 wherein the second monomer perfluoromethyl vinyl ether.

5. A process of claim 1 wherein the mol ratio of iodinated oligomer to vinyl silane is 7.5-10.

6. A process of claim 1 wherein the acid utilized in step C is selected from the group consisting of methanesulfonic acid, triflic acid, paratoluenesulfonic acid, hydrochloric acid, nitric acid and sulfuric acid.

7. A process for producing a crosslinked fluorinated polymer comprising the steps of:

A) providing an iodinated oligomer consisting essentially of:

1) 40 to 90 mole percent copolymerized units of a first monomer selected from the group consisting of vinylidene fluoride and tetrafluoroethylene;

2) 10 to 60 mole percent copolymerized units of a second monomer of the formula CF 2 ═CFOR f where R f is a perfluoroalkylene group of 1-5 carbon atoms;

3) 0 to 10 mole percent copolymerized units of a comonomer selected from the group consisting of hexafluoropropylene and tetrafluoroethylene, with the proviso that said comonomer can only be tetrafluoroethylene when said first monomer is vinylidene fluoride and said third monomer can only be hexafluoropropylene when said first monomer is tetrafluoroethylene;

4) 0 to 10 mole percent copolymerized units of a perfluoro(vinyl ether) of the formula CF 2 ═CFO(R f′ O) n (R f″ O) m R f , where R f′ and R f″ are different linear or branched perfluoroalkylene groups of 2-6 carbon atoms, m and n are independently 0-10, and R f is a perfluoroalkyl group of 1-6 carbon atoms, with the proviso that said perfluoro(vinyl ether) is different from said second monomer; and

5) 0 to 10 mole percent copolymerized units of a functional fluorovinyl ether selected from the group consisting of a functional fluorovinyl ether selected from the group consisting of

a) propanoic acid, 3-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-, methyl ester;

b) ethanesulfonyl fluoride, 2-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-1,1,2,2-tetrafluoro-;

c) 1-propanol, 3-[1-[difluoro[(trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-;

d) propanenitrile, 3-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-;

e) hexanenitrile, 2,2,3,3,4,4,5,5,6,6-decafluoro-6-[(1,2,2-trifluoroethenyl)oxy]-;

f) propanenitrile, 2,3,3,3-tetrafluoro-2-[1,1,2,2,3,3-hexafluoro-3-[(trifluoroethenyl)oxy]propoxy]-;

g) propanamide, 3-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-;

h) 1-propanol, 3-[1-[difluoro[(trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-, dihydrogen phosphate; and

i) propanoic acid, 3-[1-[difluoro[(trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro-

wherein said iodinated oligomer has a number average molecular weight of 1000 to 25,000 g/mole and wherein said oligomer has an iodine group at each chain end;

B) contacting said iodinated oligomer with a vinyl silane of the formula

CH 2 ═CY—(CH 2 ) n —SiRR′R″

where Y is a hydrogen atom or a C 1 -C 3 alkyl group, R is a methoxy or ethoxy group, and R′ and R″ are independently selected from the group consisting of methyl groups, methoxy groups and ethoxy groups, under conditions wherein the molar ratio of said iodinated oligomer to said vinyl silane is 1 to at least 2.5 to form a silicon-containing polymeric adduct that is a composition of the formula

PC—[CH 2 CYI—(CH 2 ) n SiRR′R″] m

where PC is the polymer chain of said iodinated oligomer, n is 0-2 and m is 2;

C) contacting said silicon-containing polymeric adduct with a reducing agent to form a non-iodinated silicon-containing polymeric adduct; and

D) contacting said non-iodinated silicon-containing polymeric adduct with an acid to form a crosslinked fluorinated polymer.

8. A process of claim 7 wherein the first monomer is vinylidene fluoride.

9. A process of claim 7 wherein the first monomer is tetrafluoroethylene.

10. A process of claim 7 wherein the second monomer perfluoromethyl vinyl ether.

11. A process of claim 7 wherein the molar ratio of iodinated oligomer to vinyl silane is 1 to 7.5-10.

12. A process of claim 7 wherein the acid utilized in step C is selected from the group consisting of methanesulfonic acid, triflic acid, paratoluenesulfonic acid, hydrochloric acid, nitric acid and sulfuric acid.

13. A process of claim 7 wherein the reducing agent is selected from the group consisting of tributyltin hydride, zinc in non-protonic solvents, lithium aluminum hydride, sodium borohydride, sodium amalgams, diborane and hydrogen over a catalyst.