Reversible addition-fragmentation chain transfer polymerizations of styrene with two novel trithiocarbonates as RAFT agents

Two novel reversible addition-fragmentation chain transfer (RAFT) reagents bearing functional groups, S,S′-bis(9-anthrylmethyl) trithiocarbonate (BATTC) and S,S′-bis(1-naphthylmethyl) trithiocarbonate (BNTTC) were synthesized and used for the RAFT polymerizations of styrene (St). The polymerization results showed that the RAFT polymerizations could be well controlled using BNTTC or BATTC as the RAFT agents. For example, the polymerization rates were of first-order with respect to the monomer concentration, and the molecular weights of the obtained polystyrenes (PS) with narrow molecular weight distributions increased linearly with the monomer conversions and were close to their theoretical values in the presence of BNTTC or BATTC. The successful reaction of chain extension and analysis of 1H NMR spectra confirmed the existence of the functional anthracene or naphthalene groups at the chain end of the correspondingly obtained PS. Optical properties of the obtained PS were characterized by fluorescence and UV absorption. Photochemical properties of the obtained PS end capped with anthracene were also described under irradiation of UV light.