Get access

Versatility of a succinimidyl-ester functional alkoxyamine for controlling acrylonitrile copolymerizations



Styrene/acrylonitrile (S/AN) and tert-butyl methacrylate/acrylonitrile (tBMA/AN) copolymers were synthesized in a controlled manner (low polydispersity equation image with linear growth of number average molecular weight equation image vs. conversion X) by nitroxide mediated polymerization (NMP) with a succinimidyl ester (NHS) terminated form of BlocBuilder unimolecular initiator (NHS-BlocBuilder) in dioxane solution. No additional free nitroxide (SG1) was required to control the tBMA-rich copolymerizations with NHS-BlocBuilder, a feature previously required for methacrylate polymerizations with BlocBuilder initiators. Copolymers from S/AN mixtures (AN molar initial fractions fAN,0 = 0.13–0.86, T = 115°C) had equation image = 1.14–1.26 and linear equation image versus conversion X up to X ≈ 0.6. tBMA/AN copolymers (fAN,0 = 0.10–0.81, T = 90°C) possessed slightly broader molecular weight distributions ( equation image = 1.23–1.50), particularly as the initial composition became richer in tBMA, but still exhibited linear plots of equation image versus conversion X up to X ≈ 0.6. A S/AN/tBMA terpolymerization (fAN,0 = 0.50, fS,0 = 0.40) was also conducted at 90°C and revealed excellent control with equation image = 13.6 kg/mol, equation image = 1.19, and linear equation image versus conversion X up to X = 0.54. Incorporation of AN and tBMA in the final copolymer (molar composition FAN = 0.47, FtBMA = 0.11) was similar to the initial composition and represents initial designs to make tailored, acid functional AN copolymers by NMP for barrier materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013