Synthesis and Characterization of Functional Gradient Copolymers of 2-Hydroxyethyl Methacrylate and tert-Butyl Acrylate by Atom Transfer Radical Polymerization

摘要

Functional spontaneous gradient copolymers of 2-hydroxyethyl methacrylate (HEMA) and tert-butyl acrylate (tBA) were synthesizedby atom transfer radical polymerization (ATRP) in cyclohexanone at 50°C. The copolymers were characterized by nuclear magneticresonance spectroscopy (~1H-NMR) and gel permeation chromatograph (GPC). Comonomer conversions were determined by gaschromatograph (GC) and the kinetic behavior for HEMA/tBA copolymerization was analyzed, indicating that the copolymerizationproceeds in a controlled way. The monomer reactivity ratios rHEMA = 4.497 and r_(tBA) =0.212 were estimated using an extendedKelen-Tudos method from copolymer composition data. Atomic force microscopy (AFM) images demonstrated the changes ofsurface morphology of poly(HEMA-grad-tBA) polymerized for different times and the changes were correlated to the compositionof the copolymers.