Simultaneous “Click Chemistry” and Atom Transfer Radical Emulsion Polymerization and Prepared Well-Defined Cross-Linked Nanoparticles

Abstract

Simultaneous “click chemistry” and atom transfer radical emulsion polymerization (ATREP) to prepare well-defined macromolecules and cross-linked nanoparticles are first reported in this work. First, simultaneous “click chemistry” and ATREP of styrene were conducted in the presence of p-xylylene diazide, using propargyl 2-bromoisobutyrate (PBiB) as initiator, Tween-20 as emulsifier, copper(I) bromideas catalyst, and pentamethyldiethylenetriamine (PMDETA) as ligand. The simultaneous reactions sharing a same catalyst system gave rise to diblock polystyrene (PS) with controlled molecular weight and narrow molecular weight distribution. The resulting polymers were characterized by gel permeation chromatography (GPC), FT-IR, and 1H NMR spectroscopy. Then, well-defined cross-linked PS nanoparticles with diameter in the range of 50−150 nm were prepared from a simultaneous “click chemistry” and ATREP of a mixed styrene and 4-vinylbenzyl azide using 4,4-bis((2′-bromo-2′-methylpropionyloxy)methyl)-1,6-heptadiyne (BM...