Graft copolymerization and characterization of 2-hydroxyethyl methacrylate (HEMA) onto sodium alginate using...

In this study, Alginate-g-poly(2-hydroxyethyl methacrylate) (ALG-g-PHEMA) copolymer was synthesized by the free radical addition copolymerization method to enhance the weak mechanical properties of the sodium alginate (ALG) polymer. The graft copolymer was synthesized with cerium ammonium nitrate (CAN), azobisisobutyronitrile (AIBN), benzoyl peroxide (BP), and ammonium persulfate (APS) initiators in the formation of the copolymer. The optimal grafting conditions were determined by varying the initiator, monomer, polymer, and N, N, N', N'-tetramethylethylenediamine (TEMED) concentration, and time based on the AIBN initiator, which provided the highest grafting efficiency. As a result of the optimization process, the highest grafting yield (59.12 ± 2.8 %) and grafting efficiency (32.55 ± 2.2 %) values were observed under the conditions of 150 min of grafting time, 0.4 M 2-hydroxyethyl methacrylate (HEMA) concentration, 0.03 M AIBN concentration, 0.45 × 10^-3 M TEMED concentration, and 1.75 g/dL ALG concentration. The structures of the graft copolymers were characterized using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Size Exclusion Chromatography (SEC) methods. Additionally, the in vitro cytotoxicity of the graft copolymer was assessed using the MTT assay to investigate its biocompatibility.