Functional-Polymer Library through Post-Polymerization Modification of Copolymers Having Oleate and Pentafluorophenyl Pendants.

Abstract

Poly[2-(methacryloyloxy)ethyl oleate-co-pentafluorophenyl methacrylate] [P(MAEO-co-PFPMA)] random copolymers with oleate and pentafluorophenyl side-chain pendants were synthesized. These copolymers were utilized as dual-reactive polymeric scaffolds in a range of post-polymerization modification strategies involving thiol-ene and para-fluoro-thiol substitution, amidation, trans-esterification, and epoxidation followed by amidation. The 2-(methacryloyloxy)ethyl oleate (MAEO) functional handle in the copolymer is open to functionalization at its internal double bond through thermally initiated thiol-ene reaction, whereas the pentafluorophenyl moiety of the pentafluorophenyl methacrylate (PFPMA) unit undergoes para-fluoro-thiol substitution under basic conditions at room temperature. By means of these modification approaches, the P(MAEO-co-PFPMA) copolymer was orthogonally ligated with thiol compounds having, for example, alkyl, hydroxyl, and protected amine functional groups. Furthermore, different functional groups such as benzyl, allyl, methacrylate, pyrene, and water-soluble poly(ethylene glycol) were easily introduced into the side chain of the P(MAEO-co-PFPMA) copolymer by amidation, trans-esterification, and epoxidation followed by amidation. Functionalization of both the reactive pendants with the various organic substituents was confirmed by 1 H and 19 F NMR spectroscopy, gel permeation chromatography, and fluorescence spectroscopy.