Polydiorganosiloxane-polycarbonate block cocondensates based on specific dihydroxydiphenylcyclohexanes

摘要

Polydiorganosiloxane-polycarbonate block copolymers based on dihydroxydiphenylcycloalkanes of the formula (I) <IMAGE> in which R<1> and R<2>, independently of one another, are hydrogen, halogen, preferably chlorine or bromine, C1-C8-alkyl, C5-C6-cycloalkyl, C6-C10-aryl or C7-C12-aralkyl, preferably phenyl-C1-C4-alkyl, in particular benzyl, m is an integer from 4 to 7, preferably 4 or 5, R<3> and R<4>, individually selectable for each X, are, independently of one another, hydrogen or C1-C12-alkyl, and X is carbon, with the proviso that R<3> and R<4> on at least one atom X are simultaneously alkyl, having a mean molecular weight Mw (weight average) of from 10,000 to 300,000, a content of aromatic carbonate structural units of from 75 to 99.5% by weight and a content of polydiorganosiloxane structural units of from 25 to 0.5% by weight.