公开(公告)号：US11384216B2

公开(公告)日：2022-07-12

申请号：US16435716

申请日：2019-06-10

Applicant: Arkema Inc.

Inventor： Lily Liu ,  Wayne Devonport ,  Daniel Edward Stark, Sr. ,  Matthew F. Boudreaux

IPC: C08J9/24 ,  C08J9/28 ,  C08J9/16 ,  C08J9/224 ,  C08F285/00 ,  C08F6/00

Abstract: A process for forming voided latex particles is improved by combining swelling and polymerization of an outer shell into a single step. The process includes contacting multi-stage emulsion polymer particles comprising a core, at least one intermediate shell, with a swelling agent, and polymerizing an outer shell after said contacting with swelling agent wherein the core and the at least one intermediate shell are contacted with swelling agent in the presence of less than 0.5% monomer based on the weight of the multi-stage emulsion polymer particles, and substantially all of the swelling occurs during polymerization of the outer shell.