Completely non-halogenated flame retardant polycarbonate compounds
View Patent ↗A completely non-halogenated flame retardant polycarbonate compound includes polycarbonate, non-halogenated termini-functional chemical such as vinyl-terminated siloxane and non-halogenated hydride-functional polysiloxane as non-halogenated drip suppressant ingredients which react in the presence of heat to form a drip suppressant adduct, and potassium 3-(phenylsulfonyl)benzenesulfonate as a non-halogenated char former. The compound can achieve a UL 94 rating of V-0 at a thickness of at least 3.2 mm and otherwise achieves no dripping/igniting of the cotton indicator during that test.
1. A completely non-halogenated flame retardant polycarbonate compound, comprising:
(a) from about 91.58 to about 93.51 weight percent, by weight of the compound, of polycarbonate homopolymer;
(b) from at least 1 to about 3 weight percent, by weight of the compound, of non-halogenated termini-functional chemical, wherein the non-halogenated termini-functional chemical is vinyl-terminated polydimethyl siloxane;
(c) from at least 1 to about 1.29 weight percent, by weight of the compound, of non-halogenated hydride-functional polysiloxane, wherein the non-halogenated hydride-functional polysiloxane is selected from the group consisting of poly(methyl hydrosiloxane) homopolymer, methylhydrosiloxane-dimethylsiloxane copolymer, and combinations thereof; and
(d) potassium 3-(phenylsulfonyl)benzenesulfonate;
wherein the compound is formulated with completely non-halogenated ingredients; and
wherein the compound achieves a V-1 rating or better when tested according to UL 94 at a thickness of 3.2 mm.
2. The compound of claim 1 , further comprising platinum catalyst.
3. The compound of claim 1 , further comprising a non-halogenated flame retardant.
4. The compound of claim 3 , wherein the non-halogenated flame retardant is selected from the group consisting of bisphosphate esters, polyphosphonates, polyphosphazenes, and combinations thereof.
5. The compound of claim 1 , further comprising talc.
6. The compound of claim 1 , further comprising stabilizers.
7. The compound of claim 1 , wherein the polycarbonate homopolymer is a mixture of a branched polycarbonate of virginal source, recycled source, or both, and a linear polycarbonate of virginal source, recycled source, or both.
8. An article shaped from the compound of claim 1 .