Metal-free ATRP “grafting from” technique for renewable cellulose graft copolymers

Abstract

Photoinduced metal-free “grafting from” atom transfer radical polymerization (ATRP) has been successfully applied to the fabrication of renewable cellulose graft copolymers with the aid of 2-bromo-2-phenylacetyl ester-modified ethyl cellulose as the macroinitiator. In the presence of an organic-based photoredox catalyst, “grafting from” polymerization of lauryl methacrylate from ethyl cellulose was efficiently activated and deactivated with UV irradiation, resulting in good control over molecular weight. ¹H NMR and MALDI-TOF MS confirmed highly preserved Br chain-end functionality. Furthermore, cellulose graft copolymers with a block side chain architecture were successfully prepared through chain extension by metal-free “grafting from” ATRP. We believe that this work will provide a novel approach to design well-defined cellulose graft copolymers and further expand their application fields.