Polycarbonate-polysiloxane copolymer compositions, articles formed therefrom, and methods of manufacture thereof

摘要

A polycarbonate composition comprises: a first poly(carbonate-siloxane) copolymer comprising carbonate units and siloxane units, wherein less than 0.5 mol % of the siloxane units are directly coupled to another siloxane unit; the first poly(carbonate-siloxane) copolymer comprising siloxane units with an average block length of about 10 to about 100, and a siloxane content from 5 wt % to 8 wt %; a second poly(carbonate-siloxane) copolymer comprising carbonate units and siloxane units, wherein less than 0.5 mol % of the siloxane units are directly coupled to another siloxane unit; the second poly(carbonate-siloxane) copolymer comprising siloxane units with an average block length of 10 to 100, a siloxane content from 10 wt % to 30 wt %, and wherein the weight ratio of the first poly(carbonate-siloxane) copolymer to the second poly(carbonate-siloxane) copolymer is 2 to 20; and optionally a bisphenol polycarbonate; wherein the polycarbonate composition has a total siloxane content of 2.5 wt % to 10 wt % and a molded part of 1 mm thickness has a haze of less than 2% as measured by HazeGard (ASTM D1003-00).

主权项

1. A polycarbonate composition comprising:
a first poly(carbonate-siloxane) copolymer comprising carbonate units and siloxane units, wherein less than 0.5 mol % of the siloxane units are directly coupled to another siloxane unit;
the first poly(carbonate-siloxane) copolymer comprisingsiloxane units with an average block length of about 10 to about 100, anda siloxane content from 5 wt % to 8 wt % based on the total weight of the first poly(carbonate-siloxane) copolymer; a second poly(carbonate-siloxane) copolymer comprising carbonate units and siloxane units, wherein less than 0.5 mol % of the siloxane units are directly coupled to another siloxane unit;
the second poly(carbonate-siloxane) copolymer comprisingsiloxane units with an average block length of 10 to 100,a siloxane content from 10 wt % to 30 wt % based on the total weight of the second poly(carbonate-siloxane) copolymer, andwherein the weight ratio of the first poly(carbonate-siloxane) copolymer to the second poly(carbonate-siloxane) copolymer is 2 to 20; and
optionally a bisphenol polycarbonate different from the first poly(carbonate-siloxane) copolymer and the second poly(carbonate-siloxane) copolymer; wherein the polycarbonate composition has a total siloxane content of 2.5 wt % to 10 wt % based on the total weight of the composition and a molded part of the composition with a 1 mm thickness has a haze of less than 2% as measured by HazeGard (ASTM D1003-00).