US3929934A — Novel fluoroelastomers in powder form

Claim 1

Independent Claim 106 words

COPOLYMERIZING IN AN AQUEOUS EMULSION IN THE FIRST STAGE OF A TWO-STAGE POLYMERIZATION PROCESS AND IN THE PRESENCE OF A FREE RADICAL CATALYST TO AT LEAST ABOUT 90% MONOMER CONVERSION A MIXTURE OF MONOMERS WHICH WILL RESULT IN A COPOLYMER OF ABOUT A. 65-100 WEIGHT PERCENT VINYLIDENE FLUORIDE AND A SECOND MONOMER SELECTED FROM THE GROUP CONSISTING OF PENTAFLUOROPROPENE, HEXAFLUOROPROPENE, CHLOROTRIFLUOROETHYLENE AND A PERFLUORINATED C2-C4 ALKYL VINYL ETHER, THE WEIGHT RATIO OF VINYLIDEND FLUORIDE TO THE SECOND MONOMER BEING WITHIN THE RANGE OF 0.67:1 TO 3:1, AND B. 0-35 WEIGHT PERCENT TETRAFLUOROETHYLEN, THE RESULTING FIRST-STAGE COPOLYMER HAVING A CRYSTALLINE MELTING POINT OF LESS THAN ABOUT 60*C.;

Claim 2

Dependent Claim 106 words

COPOLYMERIZING IN AN AQUEOUS EMULSION IN THE FIRST STAGE OF A TWO-STAGE POLYMERIZATION PROCESS AND IN THE PRESENCE OF A FREE RADICAL CATALYST TO AT LEAST ABOUT 90% MONOMER CONVERSION A MIXTURE OF MONOMERS WHICH WILL RESULT IN A COPOLYMER OF ABOUT A. 65-100 WEIGHT PERCENT VINYLIDENE FLUORIDE AND A SECOND MONOMER SELECTED FROM THE GROUP CONSISTING OF PENTAFLUOROPROPENE, HEXAFLUOROPROPENE, CHLOROTRIFLUOROETHYLENE AND A PERFLUORINATED C2-C4 ALKYL VINYL ETHER, THE WEIGHT RATIO OF VINYLIDEND FLUORIDE TO THE SECOND MONOMER BEING WITHIN THE RANGE OF 0.67:1 TO 3:1, AND B. 0-35 WEIGHT PERCENT TETRAFLUOROETHYLEN, THE RESULTING FIRST-STAGE COPOLYMER HAVING A CRYSTALLINE MELTING POINT OF LESS THAN ABOUT 60*C.;

Claim 3

Dependent Claim 19 words

A PROCESS FOR THE PREPARATION OF AN ELASTOMERIC, FLUORINATED COPOLYMER IN POWDER FORM, SAID PROCESS COMPRISING THE FOLLOWING STEPS:

Claim 4

Dependent Claim 19 words

A PROCESS FOR THE PREPARATION OF AN ELASTOMERIC, FLUORINATED COPOLYMER IN POWDER FORM, SAID PROCESS COMPRISING THE FOLLOWING STEPS:

Claim 5

Dependent Claim 42 words

polymerizing in the second stage in the same emulsion at least one of the same monomers as in the first stage but in such proportions that the second stage polymer, if made separately, would have a crystalline melting point above about 120*C.;

Claim 6

Dependent Claim 42 words

polymerizing in the second stage in the same emulsion at least one of the same monomers as in the first stage but in such proportions that the second stage polymer, if made separately, would have a crystalline melting point above about 120*C.;

Claim 7

Dependent Claim 42 words

PLYMERIZING IN THE SECOND STAGE IN THE SAME EMULSION AT LEAST ONE OF THE SAME MONOMERS AS IN THE FIRST STAGE BUT IN SUCH PROPORTIONS THAT THE SECOND STAGE POLYMER, IF MADE SEPARATELY, WOULD HAVE A CRYSTALLINE MELTING POINT ABOVE ABOUT 120*C.;

Claim 8

Dependent Claim 42 words

PLYMERIZING IN THE SECOND STAGE IN THE SAME EMULSION AT LEAST ONE OF THE SAME MONOMERS AS IN THE FIRST STAGE BUT IN SUCH PROPORTIONS THAT THE SECOND STAGE POLYMER, IF MADE SEPARATELY, WOULD HAVE A CRYSTALLINE MELTING POINT ABOVE ABOUT 120*C.;

Claim 9

Dependent Claim 48 words

10-35 weight percent, based on the total polymer, of a second-stage polymer of at least one of the monomers of the first-stage copolymer made in the presence of an emulsion of the first-stage copolymer, said second-stage polymer having a crystalline melting point of more than about 120*C.; and

Claim 10

Dependent Claim 48 words

10-35 weight percent, based on the total polymer, of a second-stage polymer of at least one of the monomers of the first-stage copolymer made in the presence of an emulsion of the first-stage copolymer, said second-stage polymer having a crystalline melting point of more than about 120*C.; and

Claim 11

Dependent Claim 14 words

The process of claim 1 wherein the spray-drying step is carried out at 138*-157*C.

Claim 12

Dependent Claim 29 words

The process of claim 1 wherein the only fresh monomers added to the emulsion in the second stage are selected from the group consisting of vinylidene fluoride and tetrafluoroethylene.

Claim 13

Dependent Claim 5 words

flocculating the resulting dispersion; and

Claim 14

Dependent Claim 5 words

flocculating the resulting dispersion; and

Claim 15

Dependent Claim 13 words

about 0-2 weight percent, based on the total polymer, of an anti-tack agent.

Claim 16

Dependent Claim 13 words

about 0-2 weight percent, based on the total polymer, of an anti-tack agent.

Claim 17

Dependent Claim 5 words

FLOCCULATING THE RESULTING DISPERSION; AND

Claim 18

Dependent Claim 5 words

FLOCCULATING THE RESULTING DISPERSION; AND

Claim 19

Dependent Claim 35 words

SPRAY-DRYING THE DISPERSION AT A TEMPERATURE OF ABOUT 121*-177*C.; THE RELATIVE PROPORTIONS OF THE COMPONENTS IN THE RESULTING POLYMER BEING 65-90 WEIGHT PERCENT OF THE FIRST-STAGE COPOLYMER AND 10-35 WEIGHT PERCENT OF THE SECOND-STAGE COPOLYMER.

Claim 20

Dependent Claim 35 words

SPRAY-DRYING THE DISPERSION AT A TEMPERATURE OF ABOUT 121*-177*C.; THE RELATIVE PROPORTIONS OF THE COMPONENTS IN THE RESULTING POLYMER BEING 65-90 WEIGHT PERCENT OF THE FIRST-STAGE COPOLYMER AND 10-35 WEIGHT PERCENT OF THE SECOND-STAGE COPOLYMER.

Claim 21

Dependent Claim 35 words

spray-drying the dispersion at a temperature of about 121*-177*C.; the relative proportions of the components in the resulting polymer being 65-90 weight percent of the first-stage copolymer and 10-35 weight percent of the second-stage copolymer.

Claim 22

Dependent Claim 35 words

spray-drying the dispersion at a temperature of about 121*-177*C.; the relative proportions of the components in the resulting polymer being 65-90 weight percent of the first-stage copolymer and 10-35 weight percent of the second-stage copolymer.

Claim 23

Dependent Claim 13 words

The process of claim 1 which is conducted batchwise in the same reactor.

Claim 24

Dependent Claim 14 words

The process of claim 3 which is conducted in a continuous, cascade, two-reactor system.

Claim 25

Dependent Claim 103 words

The process of claim 5 which is conducted At a temperature of about 50*-130*C. and a pressure of about 250-1500 psig at such a flow rate that at least about 90% of conversion of monomers is obtained in the first reactor; the polymer produced in the second reactor containing more than 80 weight percent of vinylidene fluoride or more than 50 weight percent of tetrafluoroethylene; the concentration of the free radical catalyst in the first reactor being about 0.001-2 weight percent based on total monomers; the emulsion being introduced into the second reactor as soon as it is withdrawn from the first reactor.

Claim 26

Dependent Claim 17 words

The process of claim 6 wherein no additional free radical catalyst is added to the second reactor.

Claim 27

Dependent Claim 12 words

A fluoroelastomer in powder form prepared by the process of claim 1.

Claim 28

Dependent Claim 12 words

A fluoroelastomer in powder form prepared by the process of claim 2.

Claim 29

Dependent Claim 12 words

A fluoroelastomer in powder form prepared by the process of claim 6.

Claim 30

Dependent Claim 10 words

A vulcanizable fluoroelastomeric composition in powder form consisting essentially of

Claim 31

Dependent Claim 10 words

A vulcanizable fluoroelastomeric composition in powder form consisting essentially of

Claim 32

Dependent Claim 16 words

A composition of claim 11 wherein the amount of anti-tack agent is about 0.5-2 weight percent.

Claim 33

Dependent Claim 11 words

A composition of claim 12, wherein the anti-tack agent is silica.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-12-29	1979-06-30	1979-12-30	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-12-29	1983-06-30	1983-12-30	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-12-29	1987-06-30	1987-12-30	$7700.00	Window Closed / Lapsed

Novel fluoroelastomers in powder form

Abstract

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