Patent ID: 6828363
Filing Date: 2004-12-07
Classification: C08F,C09D,Y02P

Abstract:
A process for preparing a polymer powder comprising:(a) reacting at least two copolymerizable ethylenically unsaturated monomers with an initiator in the presence of a supercritical fluid having a critical temperature and a critical pressure to form a homogeneous reaction mixture containing at least one polymer, at least one of the at least two monomers and supercritical fluid, wherein said homogenous reaction mixture has a temperature and pressure above the critical temperature and critical pressure of the supercritical fluid; (b) separating the homogenous reaction mixture into at least two supercritical phases by adjusting at least one process parameter selected from temperature, pressure, supercritical fluid, and combinations thereof, said at least two supercritical phases comprising a supercritical phase I containing the at least one polymer and supercritical fluid and a supercritical phase II containing the at least one monomer and supercritical fluid; (c) separating said supercritical phase I from said supercritical phase II; and (d) converting said supercritical phase I into a polymer powder by depressurizing and removing the supercritical fluid from said supercritical phase I.