Architecture of colloidal crystals constructed by silica hybrid nanoparticles

Abstract

Silica (SiO2)-crosslinked polystyrene (PS) particles possessing photofunctional N,N-diethyldithiocarbamate (DC) groups on their surface were prepared by the free-radical emulsion copolymerization of a mixture of SiO 2 (diameter Dn = 192 nm), styrene, divinyl benzene, 4-vinylbenzyl N,N-diethyldithiocarbamate (VBDC), and 2-hydroxyethyl methacrylate with a radical initiator under UV irradiation. In this copolymerization, the inimer VBDC had the formation of a hyperbranched structure by a living radical mechanism. These particles had DC groups on their surface. Subsequently, poly(methyl methacrylate) brushes encapsulated SiO2 particles were synthesized by the grafting from a photoinduced atom transfer radical polymerization (ATRP) approach of methyl methacrylate initiated by SiO 2-crosslinked PS particles as a macroinitiator. We constructed the colloidal crystals using these photofunctional particles. Moreover, the SiO 2 particle array of colloidal crystals was locked by radical photopolymerization with vinyl monomer as a matrix. © 2010 Wiley Periodicals, Inc.