Synthesis of Block Copoly(styrene-b-p-nitrophenyl methacrylate) and Its Derivatives by Atom Transfer Radical Polymerization

Abstract

The preparation of block poly(styrene-b-p-nitrophenyl methacrylate) (PSt-b-PNPMA) and its hydrolysis and amino substitution products, poly(styrene-b-methacrylic acid) (PSt-b-PMAA) and poly(styrene-b−N-butyl methacrylamide) (PSt-b-PBMAD), were described. Polystyrene macroinitiator (PSt-Br) with narrow molecular weight distribution (MWD; Mw/Mn = 1.18, Mn = 14 730) was prepared by ATRP using ethyl 2-bromobutyrate (EBB) as initiator and CuBr/2,2‘-bipyridine(bpy) as catalyst. Then, (PSt-b-PNPMA)s were synthesized by ATRP of NPMA using PSt-Br as initiator and CuBr/bpy as catalyst. GPC and NMR studies showed that the plot of ln([NPMA]0/[NPMA]) against polymerization time was linear, molecular weight (Mn) increased linearly with conversion, and the molecular weight distributions were narrow (1.26−1.38) and became narrower as Mn increased. PSt-b-PNPMA formed micelles in chloroform with PSt as shell and PNPMA as core but formed inverse micelles in dimethyl sulfoxide. PSt-b-PMAA and PSt-b-PBMAD were characterized by...