Effect of Crosslinking Agent Ratio and Temperature on Degree of Swelling in Polymer Hydrogels

In the present work graft polymers PVA-U were prepared from reaction polyvinyl alcohol PVA and urea. Were blending 8% PVA-U and 5% Hydroxypropyl methylcellulose HPMC in different ratio 100:0, 75:25 and 50:50 with using glutaraldehyde as crosslinked agent in different ratio 0.5, 0.75, 1.0 and 1.25 ml/dl. The structure of PVA-U and blend PVA-U/HPMC hydrogel was characterized by Fourier transform infrared spectroscopy FTIR, differential scanning colorimeter DSC and scanning electron microscopy SEM. Studies are made on swelling behavior for all prepared samples in different media of PH (neutral, acidic and alkaline) and deionised water.. It was observed that swelling ratio of hydrogel decreased by increasing the concentration of glutaraldehyde. The swelling ratio was measured for some hydrogel in pH7 at three different temperatures (25, 37, 50) as function of time, it was observed that swelling ratio increased with increased temperatures.. Keywords: Blend polymers, Hydrogel polymers, PVA, HPMC, Glutaraldehyd