Architecture of colloidal crystals constructed by silica hybrid nanoparticles

Abstract

Silica (SiO 2 )-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 D n ¼ 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 SiO 2 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.

When convergent syntheses of graft block copolymers diverge: The treachery of chemical images

“…The alternating copolymerization of styrene and maleimide derivatives was chosen as ideal synthetic platform. Previous reports have shown that maleimide-terminated macromonomers form alternating copolymers via copolymerization with styrene 21,22 and styrene macromonomers. [23][24][25][26][27] A BCP terminated with a maleimide should copolymerize with styrene to form a graft BCP with 50% density, and previous work has shown that copolymer composition of styrene/ maleimide copolymers can be finely tuned by adjusting the feed ratio of two different maleimides.…”