| CPC C08L 69/00 (2013.01) [C08G 64/186 (2013.01); C08G 77/448 (2013.01); C08K 2003/2241 (2013.01); C08L 2203/20 (2013.01); C08L 2205/025 (2013.01); C08L 2205/035 (2013.01); C08L 2207/53 (2013.01)] | 16 Claims |
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1. A polycarbonate composition comprising:
75 to 99 wt % of one or more bisphenol A polycarbonate homopolymers based on the total weight of the polycarbonate composition;
a poly(carbonate-siloxane) comprising a siloxane content of 35 wt % to 65 wt % based on the total weight of the poly(carbonate-siloxane) and comprising a weight average molecular weight of 32,000 to 45,000 Da, measured by gel permeation chromatography using a crosslinked styrene-divinyl benzene column, at a sample concentration of 1 milligram per milliliter, and as calibrated with bisphenol A polycarbonate standards, wherein the polycarbonate composition comprises 4 to 10 wt % siloxane content; and
wherein a sample of the composition has improved chemical resistance as compared to a reference composition,
wherein a molded sample of the polycarbonate composition has
a tensile strength retention of 80% and higher after exposure of the bar for 168 hours to SANI-CLOTH AF3 at a temperature of 23° C. under 0.5% or 1% strain compared to a non-exposed molded sample of a reference composition tested at the same temperature, and
a tensile elongation retention of 65% and higher after exposure of the bar for 168 hours to SANI-CLOTH AF3 at a temperature of 23° C. under 0.5% or 1% strain compared to a non-exposed molded sample of a reference composition tested at the same temperature,
wherein the reference composition is the same as the polycarbonate composition, except that the reference composition comprises a reference poly(carbonate-siloxane) comprising a siloxane content of 20 wt %, based on the total weight of the reference poly(carbonate-siloxane).
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