Radical polymerization of styrene mediated by 9-(1-phenylethyl)-9-((1-phenylethyl)thio)-9<italic>H</italic>-thioxanthene

Abstract

Rapid progress in controlled/living radical polymerization (CLRP) has been achieved since the end of the last century. However, the demerits and limitations of existed methods impede their industrial applications on a large scale. Therefore, it is prominent to develop new CLRP methods that are better in controlled/living features, more simple, feasible and environmental-friendly. In this article, a new thioether, 9-(1-phenylethyl)-9-((1-phenylethyl)thio)-9 H -thioxanthene (DPETTX) was synthesized. Then, the polymerization behavior of St initiated by DPETTX and both DPETTX and a small amount of 2,2′-azobisisoheptonitrile (ABVN) was studied. Results show that DPETTX can initiated the polymerization of St at a high temperature ( 100 °C ) with low initiation efficiency, while St polymerization at a low temperature ( 55 °C ) was possible in the presence of a small amount of ABVN and number average molecular weight ( M n) increased continuously with increasing conversion of St. M n increased from 27 k to 46 k when a molar ratio of ABVN/DPETTX=0.05/1 was adopted. This co-initiating system based on DPETTX and a small amount of ABVN paves a new way for developing new CLRP methods.