Temperature‐responsive alginate‐ g ‐poly( N , N ‐diethylacrylamide) copolymer: Synthesis, characterization, and swelling behavior

Temperature‐responsive polymers have recently gained importance due to their applications in drug delivery. Herein, temperature‐responsive graft copolymer (Alg‐ g ‐PDEAAm) of alginate and N , N ‐diethylacrylamide was synthesized by microwave‐assisted copolymerization using potassium persulfate/ N , N , N ′, N ′‐tetramethylethylenediamine initiator system. The reaction conditions for the best grafting (331%) have been optimized by changing microwave irradiation time, temperature, N , N ‐diethylacrylamide, and alginate concentrations. The spectroscopic characteristic, thermal properties, and surface morphology of the copolymers were investigated by FTIR, 1 H‐NMR, DSC/TGA, XRD, gel permeation chromatography, and SEM. Furthermore, low critical solution temperatures of Alg‐ g ‐PDEAAm copolymers were detected by UV spectroscopy. Swelling ratio of graft microspheres was carried out at 25, 32, and 37 °C, and microspheres were found exhibiting temperature‐responsive property. Cytotoxicity test indicated the Alg‐ g ‐PDEAAm copolymer and its microsphere were biocompatible. Therefore, based on the results the synthesized temperature‐responsive copolymer could be considered as a promising biomaterial. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46688.