Reverse ATRP of 4-vinylpyridine with Diethyl 2,3-Dicyano-2,3-Diphenylsuccinate/ CuCl_2/5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazamacrocyclotetradecane

摘要

Diethyl 2,3-dicyano-2,3-diphenylsuccinate (DCDPS) was applied to initiate reverse atom transfer radical polymerization of 4-vinylpyridine (VP) in 2-propanol with CuCl_2 and 5,5,7.12.12,14-hexamethyl-1.4,8,11-tetraazamacrocyclotetradecane (Me_6[14]aneN_4) as catalyst and ligand for the first time. First-order kinetics of the polymerization rate with respect to the monomer concentration, linear increase of the molecular weight with monomer conversion and a polydispersity index in the range of 1.15-1.28 were indicatives of controlled radical polymerization. Use of Me_6[14]aneN_4 as the ligand had many advantages over the use of hexamethyl tris[2-(dimethylamino)ethyl]amine (Me_6-TREN) and 2,2'-bipyridine (bpy). A slower polymerization rate and a broad polydispersity index were observed using CuBr_2 instead of CuCl_2 as catalyst. The block copolymer PVP-b-PAN was obtained via a conventional ATRP process in N, N-dimethylformamide (DMF) using the resulting poly (4-vinylpyridine) as macroinitiator.