公开(公告)号：WO1991018929A1

公开(公告)日：1991-12-12

申请号：PCT/US1991002763

申请日：1991-04-24

Applicant: ISP INVESTMENTS INC.

Inventor： ISP INVESTMENTS INC. ,  SHIH, Jenn, S. ,  SMITH, Terry, E. ,  ZAMORA, John ,  ECONOMIDIS, Minas

IPC: C08F02/14

CPC classification number: C08F226/10

Abstract: What is described herein is an improved precipitation polymerization process and copolymer products produced thereby. The process herein is carried out by charging a reactor with a solvent in which the copolymer product is substantially insoluble over the entire compositional range of the copolymer, preferably heptane or cyclohexane, and a polymerization initiator, heating to 50° to 150 °C, agitating, and then simultaneously feeding selected amounts of a vinyl lactam and a polymerizable carboxylic acid into said reactor below the surface of the solvent while continuing to agitate the mixture to precipitate the copolymer from solution as a fine, white powder, and recovering the copolymer of defined composition.