화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.55, No.2, 263-273, 2017
Surface Functionalized Nano-Objects from Oleic Acid-Derived Stabilizer via Non-Polar RAFT Dispersion Polymerization
Surface functionalization in a nanoscopic scaffold is highly desirable to afford nano-particles with diversified features and functions. Herein are reported the surface decoration of dispersed block copolymer nano-objects. First, side-chain double bond containing oleic acid based macro chain transfer agent (macroCTA), poly(2-(methacryloyloxy) ethyl oleate) (PMAEO), was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and used as a steric stabilizer during the RAFT dispersion block copolymerization of benzyl methacrylate (BzMA) in n-heptane at 70 degrees C. We have found that block copolymer morphologies could evolve from spherical micelles, through worm to vesicles, and finally to large compound vesicles with the increase of solvophobic poly(BzMA) block length, keeping solvophilic chain length and total solid content constant. Finally, different thiol compounds having alkyl, carboxyl, hydroxyl, and protected amine functionalities have been ligated onto the PMAEO segment, which is prone to functionalization via its reactive double bond through thiol-ene radical reactions. Thiol-ene modification reactions of the as synthesized nano-objects retain their morphologies as visualized by field emission-scanning electron microscopy. Thus, the facile and modular synthetic approach presented in this study allowed in situ preparation of surface modified block copolymer nanoobjects at very high concentration, where renewable resource derived oleate surface in the nanoparticle was functionalized. (C) 2016 Wiley Periodicals, Inc.