Preparation of polymer brushes on palygorskite surfaces via RAFT polymerization

Polymer brushes on palygorskite are successfully prepared by reversible addition fragmentation chain transfer polymerization (RAFT) technique using palygorskite as a RAFT chain transfer agent (CTA) support. The dithioester groups are introduced onto the palygorskite surface and methyl methacrylate (MMA) polymerization is performed in the presence of palygorskite supported benzyl dithiopropyltrimethoxysilane (P-Si-BDPM) which is used as chain transfer agent (CTA). The observed narrow molecular weight distributions (M-w/M-n), linear kinetic plots and linear plots of molecular weight (M,,) versus conversion for the free polymer formed in solution indicate that the chain growth from the palygorskite surface is a controlled process with a "living" characteristic. The microstructures are studied by FT-IR, Scanning probe microscope (SPM) and X-ray photoelectron spectroscopy (XPS). (C) 2007 Elsevier Ltd. All rights reserved.