Synthesis of ABCD 4-Miktoarm star-shaped quarterpolymers by combination of the click chemistry with multiple polymerization mechanism.
writer：Guowei Wang, Xiaolan Luo, Chao Liu, Junlian Huang*
keywords：Click chemistry
source：期刊
specific source：J. Polym. Sci. Part A: Polym. Chem. 2008, 46, 2154–2166.
Issue time：2008年
Well-defined ABCD 4-Miktoarm star-shaped quarterpolymers of [poly(styrene)-poly(tert-butyl acrylate)-poly(ethylene oxide)-poly(isoprene)] [star(PS-PtBAPEO-PI)] were successfully synthesized by the combination of the ‘‘click’’ chemistry and multiple polymerization mechanism. First, the poly(styryl)lithium (PSLiþ) and the polyisoprene)lithium (PILiþ) were capped by ethoxyethyl glycidyl ether (EEGE) to form the PS and PI with both an active x-hydroxyl group and an x0-ethoxyethylprotected hydroxyl group, respectively. After these two hydroxyl groups were selectively modified to propargyl and 2-bromoisobutyryl group for PS, the resulted PS was used as macroinitiator for ATRP of tBA monomer and the diblock copolymer PS-b-PtBA with a propargyl group at the junction point was achieved. Then, using the functionalized PI as macroinitiator for ROP of EO monomer and bromoethane as blocking agent, the diblock copolymer PI-b-PEO with a protected hydroxyl group at the conjunction point was synthesized. After the hydrolysis, the recovered hydroxyl group of PI-b-PEO was modified to bromoacetyl and then azide group successively. Finally, the ‘‘click’’ chemistry between them was proceeded smoothly. The obtained star-shaped quarterpolymers and intermediates were characterized by 1H NMR, FT-IR, and SEC in detail.