Reactivity ratios of controlled/living copolymerization of styrene and acrylonitrile in ionic liquid microemulsion

Abstract

In this work, reverse atom transfer radical copolymerization of styrene and acrylonitrile was investigated at 65 C in ionic liquid microemulsion using 2,2'-azobis(isobutyronitrile) (AIBN) as initiator, FeCl3· 6H2O/succnic acid as catalyst complex, and hexadecyl trimethyl ammonium bromide as surfactant. The copolymers of styrene and acrylonitrile (SAN) with predetermined molecular weights and narrow molecular weight distribution were obtained. Results showed that the polymerization proceeded in a controlled/'living' process in which the molecular weight of SAN increased with increasing the monomer conversion. The size of the resulting SAN particle was investigated. The monomer reactivity ratios increased with increasing the molar ratio of acrylonitrile to styrene. The obtained polymer was characterized by 13C nuclear magnetic resonance and gel permeation chromatography. The living characteristics were demonstrated by chain extension experiment. © 2013 The Author(s).