Silicone compositions having improved spray flammability resistance

Claim 2

A silicone composition consisting essentially of (A) from about 90 to about 99.93 parts by weight of a trimethyl end-blocked poly(dimethylsiloxane) fluid having a viscosity of about 7 to about 50 centistokes at about 25° C. and (B) from about 10 to about 0.07 parts by weight of a poly(diorganosiloxane) polymer having a weight average molecular weight of at least about 60,000 selected from the group consisting of a dimethylsiloxane homopolymer, a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units and a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units, with the proviso that said composition of (A) and (B) has a viscosity of about 20 to about 100 centistokes at about 25° C.

Claim 3

A composition as defined in claim 1, wherein said trimethyl end-blocked poly(dimethylsiloxane) fluid has a viscosity of about 10 to 30 centistokes at about 25° C.

Claim 4

A composition as defined in claim 1 wherein said silicone composition consists essentially of about 97 to about 99.85 parts by weight of said trimethyl end-blocked poly(dimethylsiloxane) fluid and about 3 to about 0.15 parts by weight of said poly(diorganosiloxane) polymer.

Claim 5

A composition as defined in claim 1, wherein said silicone composition has a viscosity of about 25 to about 50 centistokes at about 25° C.

Claim 6

A composition as defined in claim 1 wherein said silicone composition has a viscosity of about 30 to about 35 centistokes at about 25° C.

Claim 7

A composition as defined in claim 1, wherein said poly(diorganosiloxane) polymer is a dimethylsiloxane homopolymer.

Claim 8

A composition as defined in claim 1, wherein said poly(diorganosiloxane) polymer is a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units.

Claim 9

A composition as defined in claim 1, wherein said poly(diorganosiloxane) polymer is a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units.

Claim 10

A composition as defined in claim 1 wherein the trimethyl end-blocked poly(dimethylsiloxane) fluid has a viscosity of about 10 to 30 centistokes at about 25° C., wherein said silicone composition consists essentially of about 97 to about 99.85 parts by weight of said trimethyl end-blocked poly(dimethylsiloxane) fluid and about 3 to about 0.15 parts by weight of said poly(diorganopolysiloxane) polymer having a weight average molecular weight of at least about 400,000 and wherein said silicone composition has a viscosity of about 25 to about 50 centistokes at about 25° C.

Claim 11

A composition as defined in claim 9, wherein said silicone composition has a viscosity of about 30 to about 35 centistokes at about 25° C.

Claim 12

A composition as defined in claim 10, wherein said poly(diorganopolysiloxane) polymer is a dimethylsiloxane homopolymer.

Claim 13

A composition as defined in claim 10, wherein said poly(diorganopolysiloxane) polymer is a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units.

Claim 14

A composition as defined in claim 10, wherein said poly(diorganosiloxane) polymer is a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units.

Claim 15

A composition as defined in claim 1, wherein said poly(diorganosiloxane) polymer has a weight average molecular weight of at least about 400,000.

Claim 16

A process for improving the spray flammability resistance of a trimethyl end-blocked poly(dimethylsiloxane) fluid having a viscosity of about 7 to about 50 centistokes at about 25° C., said process comprising mixing about 90 to about 99.93 parts by weight of said fluid with about 10 to about 0.07 parts by weight of a poly(diorganosiloxane) polymer having a weight average molecular weight of at least about 400,000 to form a silicone composition having a viscosity of about 20 to about 100 centistokes at 25° C.

Claim 17

A process for improving the spray flammability resistance of a trimethyl end-blocked poly(dimethylsiloxane) fluid having a viscosity of about 7 to about 50 centistokes at about 25° C., said process comprising mixing about 90 to about 99.93 parts by weight of said fluid with about 10 to about 0.07 parts by weight of a poly(diorganosiloxane) polymer having a weight average molecular weight of at least about 400,000 to form a silicone composition having a viscosity of about 20 to about 100 centistokes at 25° C.

Claim 18

A process as defined in claim 15, wherein said trimethyl end-blocked poly(dimethylsiloxane) fluid has a viscosity of about 10 to 30 centistokes at about 25° C.

Claim 19

A process as defined in claim 15 wherein about 97 to about 99.85 parts by weight of said trimethyl end-blocked poly(dimethylsiloxane) fluid is mixed with about 3 to about 0.15 parts by weight of said poly(diorganosiloxane) polymer.

Claim 20

A process as defined in claim 15, wherein the formed silicone composition product has a viscosity of about 25 to about 50 centistokes at about 25° C.

Claim 21

A process as defined in claim 15, wherein the formed silicone composition product has a viscosity of about 30 to about 35 centistokes at about 25° C.

Claim 22

A process as defined in claim 15, wherein the organic pendant groups of said poly(diorganosiloxane) polymer are selected from the class consisting of hydrogen, hydrocarbon radicals free of aliphatic unsaturation, halo-substituted hydrocarbon radicals and cyano-substituted hydrocarbon radicals.

Claim 23

A process as defined in claim 15, wherein said poly(diorganosiloxane) polymer consists essentially of diorganosiloxy units selected from the class consisting of dimethylsiloxy, diethylsiloxy, diphenylsiloxy, methylethylsiloxy, methylphenylsiloxy, ethylphenylsiloxy, cyanopropyl methylsiloxy, trifluoropropyl methylsiloxy, methylvinylsiloxy, ethylvinylsiloxy, phenylvinylsiloxy and divinylsiloxy units.

Claim 24

A process as defined in claim 21, wherein said poly(diorganosiloxane) polymer is a dimethylsiloxane homopolymer.

Claim 25

A process as defined in claim 21, wherein said poly(diorganosiloxane) polymer is a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units.

Claim 26

A process as defined in claim 21, wherein said poly(diorganosiloxane) polymer is a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units.

Claim 27

A process as defined in claim 21, wherein said trimethyl end-blocked poly(dimethylsiloxane) fluid has a viscosity of about 10 to 30 centistokes at about 25° C., wherein about 97 to about 99.85 parts by weight of said trimethyl end-blocked poly(dimethylsiloxane fluid) is mixed with about 3 to about 0.15 parts by weight of said poly(diorganopolysiloxane) polymer, said polymer having a weight average molecular weight of at least about 400,000 and wherein the formed silicone composition product has a viscosity of about 25 to about 50 centistokes at about 25° C.

Claim 28

The process as defined in claim 25, wherein said formed silicone composition product has a viscosity of about 30 to about 35 centistokes at about 25° C.

Claim 29

A process as defined in claim 26, wherein said poly(diorganopolysiloxane) polymer is a dimethylsiloxane homopolymer.

Claim 30

A process as defined in claim 26, wherein said poly(diorganopolysiloxane) polymer is a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units.

Claim 31

A process as defined in claim 26, wherein said poly(diorganosiloxane) polymer is a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units.

Claim 32

In an electrical device containing a liquid dielectric composition the improvement comprising employing as the liquid dielectric composition a silicone composition having improved spray flammability resistance consisting essentially of (A) from about 90 to about 99.93 parts by weight of a trimethyl end-blocked poly(dimethylsiloxane) fluid having a viscosity of about 7 to about 50 centistokes at about 25° C. and (B) from about 10 to about 0.07 parts by weight of a poly(diorganosiloxane) polymer having a weight average molecular weight of at least about 60,000 selected from the group consisting of a dimethylsiloxane homopolymer, a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units and a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units, with the proviso that said composition of (A) and (B) has a viscosity of about 20 to about 100 centistokes at about 25° C.

Claim 33

In an electrical device containing a liquid dielectric composition the improvement comprising employing as the liquid dielectric composition a silicone composition having improved spray flammability resistance consisting essentially of (A) from about 90 to about 99.93 parts by weight of a trimethyl end-blocked poly(dimethylsiloxane) fluid having a viscosity of about 7 to about 50 centistokes at about 25° C. and (B) from about 10 to about 0.07 parts by weight of a poly(diorganosiloxane) polymer having a weight average molecular weight of at least about 60,000 selected from the group consisting of a dimethylsiloxane homopolymer, a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units and a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units, with the proviso that said composition of (A) and (B) has a viscosity of about 20 to about 100 centistokes at about 25° C.

Claim 34

An electrical device as defined in claim 30, wherein said poly(diorganosiloxane) polymer has a weight average molecular weight of at least about 400,000.

Claim 35

An electrical device as defined in claim 30, wherein said trimethyl end-blocked poly(dimethylsiloxane) fluid has a viscosity of about 10 to 30 centistokes at about 25° C.

Claim 36

An electrical device as defined in claim 30, wherein said silicone composition consists essentially of about 97 to about 99.85 parts by weight of said trimethyl end-blocked poly(dimethylsiloxane) fluid and about 3 to about 0.15 parts by weight of said poly(diorganosiloxane) polymer.

Claim 37

An electrical device as defined in claim 30, wherein said silicone composition has a viscosity of about 25 to about 50 centistokes at about 25° C.

Claim 38

An electrical device as defined in claim 30, wherein said silicone composition has a viscosity of about 30 to about 35 centistokes at about 25° C.

Claim 39

An electrical device as defined in claim 30, wherein said poly(diorganosiloxane) polymer is a dimethylsiloxane homopolymer.

Claim 40

An electrical device as defined in claim 30, wherein said poly(diorganosiloxane) polymer is a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units.

Claim 41

An electrical device as defined in claim 30, wherein said poly(diorganosiloxane) polymer is a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units.

Claim 42

An electrical device as defined in claim 30, which is a transformer.

Claim 43

An electrical device as defined in claim 30, which is a capacitor.

Claim 44

An electrical device as defined in claim 30 wherein the trimethyl end-blocked poly(dimethylsiloxane) fluid has a viscosity of about 10 to 30 centistokes at about 25° C., wherein said silicone composition consists essentially of about 97 to about 99.85 parts by weight of said trimethyl end-blocked poly(dimethylsiloxane) fluid and about 3 to about 0.15 parts by weight of said poly(diorganopolysiloxane) polymer having a weight average molecular weight of at least about 400,000 and wherein said silicone composition has a viscosity of about 25 to about 50 centistokes at about 25° C.

Claim 45

An electrical device as defined in claim 41, wherein said silicone composition has a viscosity of about 30 to about 35 centistokes at about 25° C.

Claim 46

An electrical device as defined in claim 42, wherein said poly(diorganopolysiloxane) polymer is a dimethylsiloxane homopolymer.

Claim 47

An electrical device as defined in claim 42, wherein said poly(diorganopolysiloxane) polymer is a copolymer consisting essentially of dimethylsiloxy and methylvinylsiloxy units.

Claim 48

An electrical device as defined in claim 42, wherein said poly(diorganosiloxane) polymer is a terpolymer consisting essentially of dimethylsiloxy, diphenylsiloxy and methylvinylsiloxy units.

Claim 49

An electrical device as defined in claim 42, which is a transformer.