Helical nanocomposites from chiral block copolymer templates

Abstract

Three-dimensional hexagonally packed PLLA nanohelices in the PS matrix were formed in the self-assembly of PS-PLLA chiral block copolymer. After hydrolysis of the PLLA blocks, PS with hexagonally packed helical nanochannels can be fabricated and treated as the template for the following sol-gel process. Subsequently, silica precursor mixture was introduced into the PS template by a pore-filling process. Well-defined helical nanocomposites with SiO2 inorganic nanohelices orderly dispersed in polymeric matrix can be successfully obtained after the sol-gel process. As a result, with the combination of the self-assembly of degradable block copolymers and sol-gel chemistry, we suggest a novel method for the preparation of the helical nanocomposites with ordered texture. Copyright © 2009 American Chemical Society.