Patent ID: 6365691
Filing Date: 2002-04-02
Classification: C08F,Y02P

Abstract:
A continuous, solvent-free process for obtaining solvent-free, fine white powders of high molecular weight alternating terpolymers of maleic anhydride, a C1-C4 alkyl vinyl ether and isobutylene, without odor or taste, having the molecular structure (A-B)n, where A is maleic anhydride, B is an alkyl vinyl ether or isobutylene, and n is an integer indicative of the molecular weight of the copolymer, which comprises feeding alkyl vinyl ether and isobutylene as reactants and solvents in excess over the desired 1:1 mole ratio of A:B in the copolymer, molten maleic anhydride and a free radical initiator, continuously and at predetermined feeding rates into a reactor heated at a reaction temperature of about 50Â° to 100Â° C., holding the reactants in the reactor for a predetermined average residence time, withdrawing reaction product, residual alkyl vinyl ether, isobutylene and initiator at the same rate as the feed rate of reactants into the reactor, stripping residual alkyl vinyl ether and isobutylene from the reaction product, drying the terpolymer obtained of any remaining traces of alkyl vinyl ether, and recycling recovered alkyl vinyl ether and isobutylene back into reactor as reactants and solvents.