Abstract Poly (N-acryloxysuccinimide)(PNAS) and poly (N-acryloxysuccinimide-co-N- vinylpyrrolidone)(P (NAS-co-NVP)) of adjustable molecular weights and narrow polydispersities were prepared by nitroxide-mediated polymerization (NMP) in N, N- dimethylformamide in the presence of free SG1 (N-tert-butyl-N-1-diethylphosphono-(2, 2- dimethylpropyl) nitroxide), with MAMA-SG1 (N-(2-methylpropyl)-N-(1-diethylphosphono-2, ...