Patent ID: 8668980
Filing Date: 2014-03-11
Classification: C08J,C08K,C08L,C09D,C09J,Y10T

Abstract:
1. A filled polyimide film obtained by a method comprising; a) contacting with sufficient mixing: wherein: the polyimide precursor is derived from at least 50 mole percent of an aromatic dianhydride, based upon a total dianhydride content of the polyimide precursor, and at least 50 mole percent of an aromatic diamine based upon a total diamine content of the polyimide precursor; the polyacrylonitrile domains have an average size of 2 microns or less; the polyacrylonitrile has a loading of from about 1 weight percent to about 50 weight percent, based on the weight of the polyimide obtainable from the polyimide precursor; and the loading of cellulosic polymer is from about 1 weight percent to about 40 weight percent, based on the weight of the polyimide obtainable from the polyimide precursor; b) forming a film from the polyacrylonitrile/cellulosic polymer/polyimide precursor blend; and c) heating the polyacrylonitrile/cellulosic polymer/polyimide precursor blend film to a temperature of about 300° C. to about 500° C. to convert the polyacrylonitrile domains to substantially amorphous carbon domains, the cellulosic polymer domains to dispersed closed voids having an average longest dimension of about 0.1 microns to about 10 microns and containing substantially amorphous carbon, and the polyimide precursor to polyimide.