A novel dithiocarbamate bearing azobenzene group, 2-(phenylazo-phenoxy-carbonyl) prop-2-yl 9H-carbazole-9-carbodithioate (A-PCDT), was synthesized and used as a RAFT agent in the polymerization of methyl methacrylate (MMA). The results showed that the controllability to the polymerization of MMA was promoted with A-PCDT as RAFT agent compared to 2-(ethoxycarbonyl) prop-2-yl 9H-carbazole-9-carbodithioate (EPCDT) under the same experimental conditions. The reason was attributed to the higher chain transfer constant of APCDT than that of EPCDT in the presence of more bulkier and more electrophilic azobenzene moiety. In addition, the RAFT polymerizations of St and methylacrylate (MA) using APCDT as the RAFT agent were also carried out. The ultraviolet spectrum and fluorescence spectrum of the obtained polymers were investigated. (c) 2007 Wiley Periodicals, Inc.