乳液体系中的RAFT可控/活性自由基聚合研究进展

可逆加成-断裂链转移聚合(RAFT)是新近发展起来的可控/活性自由基聚合方法。由于该方法具有适用单体范围广、反应条件温和、可采用多种聚合实施方法等优点,已成为一种有效的分子设计手段。本文总结了近几年文献报道的在乳液和细乳液体系中实施RAFT聚合反应的研究进展,对非均相体系的稳定性、聚合反应过程中的动力学特点、以及聚合产物的分子量及其分布等方面的研究进行了综述。

Reversible Addition-Fragmentation Chain Transfer Polymerization in Emulsion System

This review deals with recent progress in reversible addition-fragmentation chain transfer(RAFT) polymerization in heterogeneous phases,such as emulsion and miniemulsion systems.RAFT polymerization has been a versatile routine to synthesize a wide variety of functional monomers with controlled molecular weight and narrow MWD.Most of RAFT polymerizations have been achieved in bulk and solution systems.However,there are some issues of mass transfer and latex stability in RAFT/emulsion and RAFT/miniemulsion polymerization,leading to the failure of controlled molecular weight,the destabilization of colloidal polymers,and the formation of an intractable oily layer.The intrinsical reasons of these phenomena and improved methods have been proposed in literatures.The relationship between the mechanism of RAFT and the nucleation of latex particles in both emulsion and miniemulsion polymerization is also summarized in this article.