RAFT Polymerization of t-Butyl Acrylate and N-Benzophenone Acrylate

5BPA–BA: 3 g t-butyl acrylate (BA, 3 g, 24 mmol), N-benzophenone acrylate (BPA, 305 mg, 0.12 mmol), RAFT reagent BM1432 (48 mg, 0.12 mmol) and AIBN (1.9 mg, 0.01 mmol) were prepared in a N₂ purged glove box. Then, they were dissolved in 20 mL N₂ purged ethyl acetate and continued to purge for 10 minutes within the glove box. The reaction was carried out at 70 °C for 20 h. The polymer was precipitated into a methanol/water (30/70 volume ratio) mixture and dried in a vacuum. The number-average molecular weight (M_n) and polydispersity (M_w/M_n) were measured by gel permeation chromatography (GPC) using a Shimadzu Chromatography System (LC-24AD) with Ultrahydrogel 2000 and 120 columns connected in series. The molar ratio of BPA and HPA in the copolymer was determined by ¹H NMR.