Synthesis, characterization and swelling behavior investigation of gelatin- g-poly(acrylic acid-co-itaconic acid)

A novel pH-responsive superabsorbent hydrogel based on gelatin was prepared through crosslinking copolymerization of poly (acrylic acid) and poly (itaconic acid). The copolymerizationconditions including monomers, initiator, gelatin and crosslinker concentration, reaction temperature, and neutralization percent were systematically optimized to achieve a hydrogel with swellingcapacity as high as possible. The hydrogels structure was confirmed using Fourier-transform infrared, thermogravimetric analysis, differential scanning calorimetric and scanning electron microscopy. The swelling of the superabsorbing hydrogel was examined in buffer solutions with pH ranged 3-12. Moreover, the swelling of the hydrogel was conducted in 0.15 M aqueous solutionsof NaCl, CaCl2, and AlCl3. Due to the high swelling capacity in salt solutions, the hydrogel may be referred to as low-salt sensitive superabsorbent.

Keywords:

Superabsorbent , hydrogel , acrylic acid , itaconic acid , swelling behavior