Thermoresponsive and biocompatible poly(vinyl alcohol)-graft-poly(N,N-diethylacrylamide) copolymer: Microwave-assisted synthesis, characterization, and swelling behavior

Novel thermoresponsive poly(vinyl alcohol)-graft-poly(N,N-diethylacrylamide) (PVA-g-PDEAAm) copolymers were prepared by microwave-assisted graft copolymerization using a potassium persulfate/N,N,N,N-tetramethylethylenediamine (KPS/TEMED) initiator system. The structures of PVA-g-PDEAAm copolymers were characterized by H-1-NMR, Fourier transform infrared spectroscopy, differential scanning calorimetry/thermogravimetric analysis, gel permeation chromatography, X-ray diffraction, and scanning electron microscopy. The effects of various process parameters on grafting were systematically studied: microwave power, KPS, monomer and PVA concentrations, and ultraviolet irradiation. Under optimal conditions, the maximum grafting percent and graft efficiency were 101% and 93%, respectively. Furthermore, a lower critical temperature of copolymers was measured in the range 29-31 degrees C by ultraviolet spectroscopy. The swelling behavior of graft membranes was carried out at various temperatures, and the results showed that the swelling behavior of membranes was dependent on the temperature. In vitro cell culture studies using L929 fibroblast cells confirmed cell compatibility with the PVA-g-PDEAAm copolymer and its membrane, making them an attractive candidate for drug delivery systems. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45969.