Patent ID: 7662909
Filing Date: 2010-02-16
Classification: C08G,C08K,C08L,G02B

Abstract:
1. A method for preparing a composition comprising a polysulfone polymer with low yellow coloration, the method comprising: reacting 2,2-bis(4-hydroxyphenyl)propane with at least one diarylsulfone compound to form a low-color content polysulfone polymer, and blending the formed low-color content polysulfone polymer with at least one additive selected from the group consisting of an organic phosphorous-comprising melt stabilizer, a blue to violet dye, an organic optical brightener, and mixtures thereof, to form a low-color content polysulfone polymer blend, wherein the 2,2-bis(4-hydroxyphenyl)propane comprises less than 0.27% by total weight of 2-(4-hydroxyphenyl)-2-(2-hydroxyphenyl)propane and 2,2-bis(2-hydroxyphenyl)propane.