Synthesis of well-defined comb-like amphiphilic copolymers with protonizable units in the pendent chains:: 2.: Poly(2-(dimethylamino)ethyl methacrylate) grafted poly(methylmethacrylate-co-2-hydroxyethyl methacrylate) copolymers and their association behavior in aqueous solution

Narrow-distribution, well-defined comb-like amphiphilic copolymers are reported in this work. The copolymers are composed of poly(methyl methacrylate-co-2-hydroxyethyl methacrylate) (P(MMA-co-HEMA)) as the backbones and poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) as the grafted chains, with the copolymer backbones being synthesized via atom-transfer radical polymerization (ATRP) and the grafted chains by oxyanionic polymerization. The copolymers were characterized by gel permeation chromatography (GPC), Fourier-transform infrared (FT-IR) spectroscopy and H-1 NMR spectroscopy. The aggregation behavior in aqueous solutions of the comb-like amphiphilic copolymers was also investigated. H-1 NMR spectroscopic and surface tension measurements all indicated that the copolymers could form micelles in aqueous solutions and they possessed high surface activity. The results of dynamic light scattering (DLS) and scanning electron microscopy (SEM) investigations showed that the hydrodynamic diameters of the comb-like amphiphilic copolymer aggregates increased with dilution. Because of the protonizable properties of the graft chains, the surface activity properties and micellar state can be easily modulated by variations in pH. (C) 2004 Society of Chemical Industry.