New Self-Assembling Polyaspartamide-Based Brush Copolymers Obtained by Atom Transfer Radical Polymerization

Abstract

A simple and efficient method for the synthesis of polyaspartamide-based brush copolymers using Atom Transfer Radical Polymerization (ATRP) is here presented. The syntheses were performed by using two subsequent steps. In the first step the macroinitiator was obtained by the conjugation of a proper number of 2-bromoisobutyryl bromide (BIB) residues to the α,β-poly(N-2-hydroxyethyl)-d,l-aspartamide (PHEA) side chains, obtaining the PHEA−BIB copolymer. PHEA−BIB copolymer was used as “multi-functional macroinitiator” for the polymerization via ATRP of hydrophilic methacrylic monomers, such as methacrylic acid (MA), obtaining PHEA−IB−poly(MA) copolymer, sodium methacrylate (MANa+), obtaining PHEA−IB−poly(MANa+) copolymer, or hydrophobic monomer such as butyl methacrylate (BMA), obtaining PHEA−IB−poly(BMA) copolymer. BMA was also homopolymerized subsequently MANa+ polymerization, extending the poly(MANa+) chains by poly(BMA) chains arising PHEA−IB−poly(MANa+)-block-poly(BMA) copolymer. Different solvent and te...