ACRYLIC ACID/METHYL METHACRYLATE HYDROGELS. I. EFFECT OF COMPOSITION ON MECHANICAL AND THERMODYNAMIC PROPERTIES.

The mechanical and thermodynamic properties of poly(acrylic acid-co-methyl methacrylate) hydrogels with varying ratios of AA/MMA are reported. Swelling capacity increases but elasticity decreases as the content of AA in the hydrogels increases. Thermodynamic analysis indicates that swelling is an unfavorable and endothermic process. Both thermodynamic quantities increase with increasing hydrophobic nature of the hydrogel. The amount of freezing and non-freezing water in the hydrogels was determined by DSC. The ratio of non freezing to total water content increases with the increasing hydrophobic nature of the hydrogels. [ABSTRACT FROM AUTHOR]