Thermoplastic molding compositions and process

Claim 2

A flame retardant thermoplastic molding composition having improved physical properties, the composition consisting essentially of an intimate mixture of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo- or copolyester resin; (b) (i) a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic polycarbonate derived from bisphenol A; or (ii) a mixture of a reinforcing amount of glass fibers and a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic polycarbonate derived from bisphenol-A; (c) a flame retardant amount of a flame retardant additive; and (d) a mineral filler selected from the group consisting of silica, mica, talc, pysophillite, wollastonite and mineral wool, and mixtures of any of the foregoing; component (d) being present in an amount of from about 5 to about 40% by weight sufficient to provide electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.

Claim 3

A composition as defined in claim 1 wherein component (a) is linear or branched.

Claim 4

A composition as defined in claim 1 wherein component (d) comprises from about 10 to 30% by weight.

Claim 5

A composition as defined in claim 1 wherein component (b) is (b) (i) and (b) (i) contains a copolymer consisting of ethylene and vinyl acetate that contains less than 50% by weight vinyl acetate, the remainder ethylene.

Claim 6

A composition as defined in claim 1 wherein, component (b) is (b) (i), and (b) (i) said copolymer is a copolymer selected from the group consisting of one derived from ethylene, vinyl acetate and carbon monoxide, ethylene, vinyl acetate and methacrylic acid, and ethylene, vinyl acetate and acrylic acid.

Claim 7

A composition as defined in claim 1 wherein flame retardant component (c) comprises a halogenated aromatic ether or a halogenated aromatic polycarbonate homo- or copolymer.

Claim 8

A composition as defined in claim 1, wherein said filler component (d) is silica, talc or mica.

Claim 9

In a process for the preparation of a flame retardant molding composition having improved physical properties comprising forming an intimate melt-blended admixture consisting essentially of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo- or copolyester resin; (b) (i) a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic polycarbonate derived from bisphenol-A; or (ii) a reinforcing amount of glass fibers and a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic polycarbonate derived from bisohenol-A and (c) a flame retardant amount of a flame retardant additive; the improvement comprising the step of including in said intimate admixture (d) a mineral filler selected from the group consisting of silica, mica, talc, pyrophillite, wollastonite and mineral wool, and mixtures of any of the foregoing in an amount of from about 5 to 40% by weight at least sufficient to provide the composition with electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.

Claim 10

In a process for the preparation of a flame retardant molding composition having improved physical properties comprising forming an intimate melt-blended admixture consisting essentially of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo- or copolyester resin; (b) (i) a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic polycarbonate derived from bisphenol-A; or (ii) a reinforcing amount of glass fibers and a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic polycarbonate derived from bisohenol-A and (c) a flame retardant amount of a flame retardant additive; the improvement comprising the step of including in said intimate admixture (d) a mineral filler selected from the group consisting of silica, mica, talc, pyrophillite, wollastonite and mineral wool, and mixtures of any of the foregoing in an amount of from about 5 to 40% by weight at least sufficient to provide the composition with electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.

Claim 11

A process as defined in claim 8 wherein component (d) is added in an amount comprising from about 10 to 30% by weight of the total weight of the composition.

Claim 12

A flame retardant thermoplastic molding composition having improved physical properties, the composition consisting of an intimate admixture of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo- or copolyester resin; (b) (i) a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic homopolycarbonate; (ii) a high molecular weight polyethylene terephthalate resin; (iii) a mixture of a reinforcing amount of glass fibers and a copolymer comprised of with an aromatic homopolycarbonate; (iv) a mixture of a reinforcing amount of glass fibers and a high molecular weight polyethylene terephthalate resin, or (v) a mixture of (i), (ii) and a reinforcing amount of glass fibers; (c) a flame retardant amount of a flame retardant additive; and (d) a mineral filler selected from the group consisting of silica, mica, talc, pyrophillite, wollastonite and mineral wool, and mixtures of the foregoing; component (d) being present in an amount of from about 5 to about 40% by weight sufficient to provide electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.

Claim 13

A flame retardant thermoplastic molding composition having improved physical properties, the composition consisting of an intimate admixture of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo- or copolyester resin; (b) (i) a copolymer comprised of ethylene and vinyl acetate in combination with an aromatic homopolycarbonate; (ii) a high molecular weight polyethylene terephthalate resin; (iii) a mixture of a reinforcing amount of glass fibers and a copolymer comprised of with an aromatic homopolycarbonate; (iv) a mixture of a reinforcing amount of glass fibers and a high molecular weight polyethylene terephthalate resin, or (v) a mixture of (i), (ii) and a reinforcing amount of glass fibers; (c) a flame retardant amount of a flame retardant additive; and (d) a mineral filler selected from the group consisting of silica, mica, talc, pyrophillite, wollastonite and mineral wool, and mixtures of the foregoing; component (d) being present in an amount of from about 5 to about 40% by weight sufficient to provide electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.

Claim 14

A flame retardant thermoplastic composition as defined in claim 10 wherein the mineral filler is silica.

Claim 15

A flame retardant thermoplastic composition as defined in claim 10 wherein the mineral filler is mica.

Claim 16

A flame retardant thermoplastic composition as defined in claim 10 wherein the mineral filler is talc.

Claim 17

A flame retardant thermoplastic molding composition as defined in claim 10 wherein the mineral filler is pyrophillite.

Claim 18

A flame retardant thermoplastic molding composition as defined in claim 10 wherein the mineral filler is wollastonite.

Claim 19

A flame retardant thermoplastic molding composition as defined in claim 10 wherein the mineral filler is mineral wool.

Claim 20

A flame retardant thermoplastic molding composition having improved physical properties, the composition consisting of an intimate admixture of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo or copolyester resin; (b) (i) a copolymer consisting of ethylene and vinyl acetate in combination with an aromatic homopolycarbonate; (ii) a high molecular weight polyethylene terephthalate resin; (iii) a mixture of a reinforcing amount of glass fibers and component (b) (i); (iv) a mixture of a reinforcing amount of amount of glass fibers and component (b) (ii); or (v) a mixture of a reinforcing amount of glass fibers, component (b) (i) and component (b) (ii); (c) a flame retardant amount of a flame retardant additive; and (d) a mineral filler selected from the group consisting of silica, mica, talc, pyrophillite, wollastonite and mineral wool, and mixtures of the foregoing; component (d) being present in an amount of from about 10 to about 30% by weight sufficient to provide electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.

Claim 21

A flame retardant thermoplastic molding composition having improved physical properties, the composition consisting of an intimate admixture of: (a) a high molecular weight poly(1,4-butylene terephthalate) homo or copolyester resin; (b) (i) a copolymer consisting of ethylene and vinyl acetate in combination with an aromatic homopolycarbonate; (ii) a high molecular weight polyethylene terephthalate resin; (iii) a mixture of a reinforcing amount of glass fibers and component (b) (i); (iv) a mixture of a reinforcing amount of amount of glass fibers and component (b) (ii); or (v) a mixture of a reinforcing amount of glass fibers, component (b) (i) and component (b) (ii); (c) a flame retardant amount of a flame retardant additive; and (d) a mineral filler selected from the group consisting of silica, mica, talc, pyrophillite, wollastonite and mineral wool, and mixtures of the foregoing; component (d) being present in an amount of from about 10 to about 30% by weight sufficient to provide electrical arc track resistance superior to that of a corresponding composition in which mineral filler component (d) is not present.