title: Synthesis and self-assembly of thermo/pH-responsive double hydrophilic brush-coil copolymer with poly(L-glutamic acid) side chains.
abstract: We report on the synthesis and self-assembly behavior of a well-defined double hydrophilic brush-coil copolymer with poly(N-isopropylacrylamide)-b-poly(glycidly methacrylate) (PNIPAM-b-PGMA) as backbone and poly(L-glutamic acid) (PLGA) as brush. The PNIPAM-b-PGMA was firstly prepared by the sequential reversible addition-fragmentation chain transfer polymerization of N-isopropylacrylamide and glycidly methacrylate. The obtained diblock copolymer was reacted with ethylenediamine (EDA) yielding the aminated macroinitiator (PNIPAM-b-PGMA-EDA), which was then used to initiate ring-opening polymerization of γ-benzyl-L-glutamate-N-carboxyanhydride (BLG-NCA) to give PNIPAM-b-(PGMA-g-PBLG) copolymer. After the deprotection of benzyl groups on PBLG, double hydrophilic brush-coil copolymer, PNIPAM-b-(PGMA-g-PLGA), was obtained. The thermo- and pH-responsive micellization behaviors of PNIPAM-b-(PGMA-g-PLGA) in aqueous solution were investigated by fluorescence spectroscopy, (1)H NMR, dynamic light scattering, scanning electron microscopy, and circular dichroism. It can self-assemble into PNIPAM-core micelles at pH 10 and elevated temperature and PLGA-core micelles at pH 4 and room temperature. Such brush-coil copolymers have the potential applications as biomedical and intelligent materials.
authors: Anhui Key Laboratory of Functional Molecular Solids, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, China. tycang@mail.ahnu.edu.cn
authors: Yecang
authors: Y
authors: Tang
authors: Li
authors: L
authors: Liu
authors: Jianhua
authors: J
authors: Wu
authors: Jixiong
authors: J
authors: Duan
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D019344:Lactic Acid / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry*; D008823:Micelles; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer
chemical_list: D000180:Acrylic Resins; D004852:Epoxy Compounds; D008689:Methacrylates; D008823:Micelles; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; C052970:poly-N-isopropylacrylamide; D011100:Polyglycolic Acid; D019344:Lactic Acid; C007870:glycidyl methacrylate