Low density resin systems for improved filament-wound composites useful as rocket motor cases

Claim 2

A cured filament-wound composite comprising fibers and resin, said resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by comprising an aromatic vinyl hydrocarbon monomer and as its major component poly(1,2-butadiene), carboxy-terminated poly(1,2-butadiene) or mixtures thereof and by having a viscosity at 45° C. of less than 2000 cps.

Claim 3

The composite of claim 1 wherein said fibers are selected from among the group consisting of carbon (graphite) filaments, glass filaments, boron filaments and high modulus organic polymer filaments.

Claim 4

The composite of claim 1 wherein said fibers are aramid fibers.

Claim 5

The composite of claim 2 wherein said resin, in its uncured state, comprises from 50 to 90% by weight poly(1,2-butadiene), from 10 to 45% of aromatic vinyl hydrocarbon monomer and an effective curing amount in the range of from 1 to 10% of free radical generating curing agent.

Claim 6

The composite of claim 4 wherein said aromatic vinyl hydrocarbon monomer comprises a material selected from the group consisting of styrene and styrene substituted with up to two groups independently selected from alkyls and alkenyls of from 1 to 5 carbon atoms.

Claim 7

The composite of claim 5 additionally comprising from 1 to 10% by weight of a copolymerizable flexibilizing monomer.

Claim 8

The composite of claim 6 wherein said aromatic vinyl hydrocarbon monomer is t-butyl styrene and said curing agent comprises an organic peroxide.

Claim 9

The composite of claim 5 wherein said aromatic vinyl hydrocarbon monomer is t-butyl styrene and said curing agent comprises an organic peroxide.

Claim 10

The composite of claim 2 wherein said resin, in its uncured state, comprises from 60 to 80% by weight poly(1,2-butadiene), from 20 to 35% of aromatic vinyl hydrocarbon monomer selected from the group consisting of styrene and styrene substituted with up to two groups independently selected from alkyls and alkenyls of from 1 through 5 carbon atoms, from 3 to 10% of a copolymerizable flexibilizing monomer, and from 1 to 5% of an organic peroxide curing agent.

Claim 11

The composite of claim 9 wherein said flexibilizing monomer is a glycol dimethacrylate.

Claim 12

The composite of claim 10 wherein said aromatic vinyl hydrocarbon monomer is t-butyl styrene.

Claim 13

A cured filament-wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments, boron filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 63 to 68% by weight poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85%, from 26 to 30% t-butyl styrene, from 4 to 6% tetraethyleneglycol dimethacrylate, from 1 to 4% dicumyl peroxide and from 0.75 to 1.25% of dibenzoyl peroxide.

Claim 14

A cured filament-wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments, boron filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 63 to 68% by weight poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85%, from 26 to 30% t-butyl styrene, from 4 to 6% tetraethyleneglycol dimethacrylate, from 1 to 4% dicumyl peroxide and from 0.75 to 1.25% of dibenzoyl peroxide.

Claim 15

The composite of claim 12 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 16

The composite of claim 2 wherein said resin, in its uncured state, comprises a mixture of poly(1,2-butadiene) and carboxy-terminated poly(1,2-butadiene).

Claim 17

The composite of claim 14 wherein said mixture is present in an amount of from 50 to 90% of the weight of said resin in its uncured state.

Claim 18

The composite of claim 15 wherein in said mixture poly(1,2-butadiene) and carboxy-terminated poly(1,2-butadiene) are in a weight ratio of from 1:2 to 2:1 inclusive.

Claim 19

The composite of claim 2 wherein said resin in its uncured state comprises from 50 to 90% by weight of a 1:2 to 2:1 weight ratio mixtures of poly(1,2-butadiene) and carboxy-terminated poly(1,2-butadiene), from 10 to 40% of aromatic vinyl hydrocarbon monomer, an effective curing amount in the range of from 1 to 10% of free radical-generating curing agent and from 2 to 15% of liquid epoxy group-containing material, the amount of said epoxy group-containing material being selected to provide about one epoxy for each carboxy present in said carboxy-terminated poly(1,2-butadiene).

Claim 20

The composite of claim 17 wherein said fibers are aramid fibers.

Claim 21

The composite of claim 17 wherein said aromatic vinyl hydrocarbon monomer is selected from the group consisting of styrene and styrene substituted with up to two groups independently selected from alkyls and alkenyls of from 1 through 5 carbon atom.

Claim 22

The composite of claim 19 wherein said aromatic vinyl hydrocarbon monomer is t-butyl styrene.

Claim 23

The composite of claim 2 wherein said resin in its uncured state comprises from 60 to 80% by weight of an about 1:1 weight ratio mixture of poly(1,2-butadiene) and carboxy-terminated poly(1,2-butadiene), from 15 to 30% of aromatic vinyl hydrocarbon monomer selected from the group consisting of styrene and styrene substituted with up to two groups independently selected from alkyls and alkenyls of from 1 through 5 carbon atoms, an effective curing amount in the range of from 2 to 6% of free radical-generating curing agent and from 3 to 12% of liquid epoxy group-containing material, the amount of said epoxy group-containing material being selected to provide about one epoxy for each carboxy present in said carboxy-terminated poly(1,2-butadiene).

Claim 24

The composite of claim 21 wherein said epoxy group-containing material is selected from the group consisting of liquid aromatic, aliphatic and cycloaliphatic di-, tri- and poly-epoxides.

Claim 25

The composite of claim 22 wherein said curing agent comprises an organic peroxide, said monomer comprises t-butyl styrene and said epoxy group containing material is selected from the group consisting of 1,4-butanediol diglycidyl ether, vinylcyclohexane dioxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate, resorcinol diglycidyl ether, bis (3,4-epoxy-6-methylcyclohexyl-methyl) adipate, diglycidyl ether-bisphenol-A, diglycidyl ether of propylene glycol, triglycidyl ether of trimethylolpropane, triglycidyl ether of glycerine, diglycidyl ester of linoleic dimer acid, polyallylglycidyl ether, triglycidyl-p-aminophenol, diglycidyl hydantoin, epoxy novolac, and diglycidyl ether of methylene-bis-cyclohexanol.

Claim 26

The composite of claim 23 wherein the resin in its uncured state additionally comprises from 0.01 to 1% of an epoxy accelerator.

Claim 27

A cured filament wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments, boron filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 67 to 73% by weight of a 1:1 weight ratio mixture of poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85% and carboxy-terminated poly(1,2-butadiene) of molecular weight between 1000 and 3300 and of isomeric purity greater than 85%, from 19% to 23% t-butyl styrene, from 2 to 5% dicumyl peroxide and from 5.0-6.5% of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate.

Claim 28

A cured filament wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments, boron filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 67 to 73% by weight of a 1:1 weight ratio mixture of poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85% and carboxy-terminated poly(1,2-butadiene) of molecular weight between 1000 and 3300 and of isomeric purity greater than 85%, from 19% to 23% t-butyl styrene, from 2 to 5% dicumyl peroxide and from 5.0-6.5% of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate.

Claim 29

The composite of claim 25 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 30

The composite of claim 26 wherein said resin additionally consists essentially of from 0.15 to 0.25% by weight of chromium octoate.

Claim 31

A cured filament wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and, when uncured, by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 65 to 71% by weight of 1:1 weight ratio mixture of poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85% and carboxy-terminated poly(1,2-butadiene) of molecular weight between 1000 and 3300 and of isomeric purity greater than 85%, from 18 to 22% t-butyl styrene, from 2 to 5% dicumyl peroxide and from 8 to 10% of 4,4'-isopropylidene dicyclohexanol (glycidyl derivative).

Claim 32

A cured filament wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and, when uncured, by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 65 to 71% by weight of 1:1 weight ratio mixture of poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85% and carboxy-terminated poly(1,2-butadiene) of molecular weight between 1000 and 3300 and of isomeric purity greater than 85%, from 18 to 22% t-butyl styrene, from 2 to 5% dicumyl peroxide and from 8 to 10% of 4,4'-isopropylidene dicyclohexanol (glycidyl derivative).

Claim 33

The composite of claim 28 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 34

A cured filament wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments, boron filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 68 to 74% by weight of a 1:1 weight ratio mixture of poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85% and carboxy-terminated poly(1,2-butadiene) of molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85%, from 19 to 24% t-butyl styrene, from 2 to 5% dicumyl peroxide and from 3.5 to 5% by weight of trigylcidal p-aminophenol.

Claim 35

A cured filament wound composite comprising fibers selected from among the group consisting of carbon filaments, glass filaments, boron filaments and high modulus organic polymer filaments and a resin characterized when cured by a density of less than 1.05 g/cc, and by a saturation water pick-up of less than 1% by weight, and when uncured by having a viscosity at 45° C. of less than 2000 cps, and by consisting essentially of from 68 to 74% by weight of a 1:1 weight ratio mixture of poly(1,2-butadiene) of average molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85% and carboxy-terminated poly(1,2-butadiene) of molecular weight between 1000 and 3300 daltons and of isomeric purity greater than 85%, from 19 to 24% t-butyl styrene, from 2 to 5% dicumyl peroxide and from 3.5 to 5% by weight of trigylcidal p-aminophenol.

Claim 36

The composite of claim 30 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 37

The composite of claim 2 wherein said resin, in its uncured state, comprises carboxy-terminated poly(1,2-butadiene).

Claim 38

The composite of claim 2 wherein said resin in its uncured state comprises from 50 to 90% by weight of carboxy-terminated poly(1,2-butadiene), from 5 to 25% of aromatic vinyl hydrocarbon monomer, an effective curing amount in the range of from 1 to 10% of free radical-generating curing agent and from 5 to 30% of liquid epoxy group-containing material, the amount of said epoxy group-containing material being selected to provide about one epoxy for each carboxy present in said carboxy-terminated poly(1,2-butadiene).

Claim 39

The composite of claim 33 wherein said aromatic vinyl hydrocarbon monomer is selected from the group consisting of styrene and styrene substituted with up to two groups independently selected from alkyls and alkenyls of from 1 through 5 carbon atoms.

Claim 40

The composite of claim 34 wherein said aromatic vinyl hydrocarbon monomer is t-butyl styrene.

Claim 41

The composite of claim 2 wherein said resin in its uncured state comprises from 60 to 80% by weight of carboxy-terminated poly(1,2-butadiene), from 7 to 15% of aromatic vinyl hydrocarbon monomer selected from the group consisting of styrene and styrene substituted with up to two groups independently selected from alkyls and alkenyls of from 1 through 5 carbon atoms, an effective curing amount in the range of from 2 to 6% of an organic peroxy curing agent and from 6 to 28% of liquid epoxy group-containing material, the amount of said epoxy group-containing material being selected to provide about one epoxy for each carboxy present in said carboxy-terminated poly(1,2-butadiene) and said epoxy group being selected from the group consisting of 1,4-butanediol diglycidyl ether, vinylcyclohexane dioxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate, resorcinol diglycidyl ether, bis (3,4-epoxy-6-methylcyclohexyl-methyl) adipate, diglycidyl ether-bisphenol-A, diglycidyl ether of propylene glycol, triglycidyl ether of trimethylolpropane, triglycidyl ether of glycerine, diglycidyl ester of linoleic dimer acid, polyallylglycidyl ether, triglycidyl-p-aminophenol, diglycidyl hydantoin, epoxy novolac, and diglycidyl ether of methylene-biscyclohexanol.

Claim 42

The composite of claim 36 wherein said carboxy-terminated poly(1,2-butadiene) has an average molecular weight between 1000 and 3300 daltons and an isomeric purity of greater than 85%, said aromatic vinyl hydrocarbon monomer is t-butyl styrene, and said curing agent is dicumyl peroxide.

Claim 43

The composite of claim 37 wherein said resin consists of 65 to 71% by weight carboxy-terminated poly(1,2-butadiene), 9 to 12% t-butyl styrene, 2 to 4% dicumyl peroxide, and 18 to 21% 4,4'-isopropylidene dicyclohexanol glycidyl derivative.

Claim 44

The composite of claim 38 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 45

The composite of claim 37 wherein said resin consists essentially of 74 to 80% by weight carboxy-terminated poly(1,2-butadiene), 10 to 13% t-butyl styrene, 2 to 4% dicumyl peroxide, and 7.5 to 10% triglycidyl-p-aminophenol.

Claim 46

The composite of claim 40 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 47

The composite of claim 37 wherein said resin consists essentially of 65 to 71% by weight carboxy-terminated poly(1,2-butadiene), 9 to 11% t-butyl styrene, 2 to 4% dicumyl peroxide, 4.5 to 6% diglycidyl derivative of substituted hydrocarbon and 14.5 to 17.0% diglycidyl ester of linoleic dimer acid.

Claim 48

The composite of claim 42 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 49

The composite of claim 37 wherein said resin consists essentially of 64 to 69% by weight carboxy-terminated poly(1,2-butadiene), 9.5 to 10.5% t-butyl styrene, 2 to 4% dicumyl peroxide, 3.5 to 4.1% triglycidyl-p-amino-phenol and 14.5 to 17.5% diglycidyl ester of linoleic dimer acid.

Claim 50

The composite of claim 44 wherein said fibers are aramid filaments in the amount of from 70 to 80% of the composite weight.

Claim 51

The composite of claim 3 embodied as a filament-wound rocket motor case.

Claim 52

The composite of claim 9 embodied as a filament-wound rocket motor case.

Claim 53

The composite of claim 17 embodied as a filament-wound rocket motor case.

Claim 54

The composite of claim 33 embodied as a filament-wound rocket motor case.