Preparation and Characterization of Polyampholytic Poly(acrylic acid acrylamide) Hydrogels and Investigation of Swelling Behavior in Different Media

摘要

Stimuli-responsive polyampholyte hydrogels were synthesized by the copolymerization of acrylic acid (AAc) and acrylamide (AAm) by thermal methods. Polyampholytic hydrogels are crosslinked networks composed of positively and negatively charged repeating units that show entirely different properties from their origins. In this work, polyampholytic poly (acrylic acid acrylamide) hydrogels prepared in different molar ratio in feed composition by thermal methods. The structures of hydrogels were characterized by FTIR analysis. Thermal stabilities of the hydrogels were investigated using TGA analysis. The swelling behavior of hydrogels investigated by some parameters such as pH, salt concentration and temperature. We determined this swelling capacity in different temperatures (25, 50 and 70 °C) and different pH (2, 7 and 12). In addition, we investigated the effects of different salts such as LiCl, CaCl2, Na2SO4 and NaCl with concentration of 0.1, 0.2 and 0.3M on swelling properties.