In-Situ UV-Photopolymerized PVA-g-GMA Hydrogels for Biomedical Applications: I. Synthesis, Characterizations and Grafting Optimization

Abstract

This work explores the synthesis and grafting optimization of PVA-g-GMA hydrogels. The grafting of poly (vinyl alcohol) (PVA) with glycidyl methacrylate (GMA) was conducted by the trans-esterification reaction via introducing methacryloyl groups into PVA chains and glycidol was formed as by-product. The grafting reaction conditions of PVA-g-GMA e.g. GMA concentrations and reaction temperature were optimized. The kinetic parameters e.g. grafting efficiency (GE) and grafting percentage (GP%) were calculated to optimize the grafting reaction, while yield (%) was determined to monitor the hydrogels formation. The instrumental characterizations e.g. 1 H-NMR, FTIR, SEM and TGA/DSC, were investigated for verifying the grafting reaction. The UV-photopolymerization was used for photocrosslinking the water-soluble PVA-g-GMA using Irgacure 2959 (I 2959 ) as a photoinitiator. Results revealed that the grafting reaction dramatically increased with increase of both GMA concentration until 0.15M and reaction temperature at 60 o C. Also, the surface morphological of PVA-g-GMA freeze-dried gels was found more compacted, smooth and uniform due to the grafting process. A significant thermal stability was noticed, due to grafting reaction of PVA-g-GMA throughout TGA and DSC results. The obtained results are very promising and opening new area for conducting further investigations considering the very low price of the used UV crosslinking method compared to the chemical crosslinking method.