Abstract
This paper investigates the swelling properties of homopolymer and copolymer hydrogels. Copolymeric hydrogels based on N, N-dimethyl acrylamide and acrylic acid (poly(DMA-co-AAc) as well as homopolymer hydrogels based on acrylic acid (polyAAc) were synthesized by radical technique in aqueous solutions using ammonium persulfate as an initiator and N, N-methylene-bis-acrylamide as a crosslinking agent. The properties of hydrogels examined including scanning electron microscopy (SEM) and FT-IR. The results indicate that the poly(DMA-co-AAc) copolymer has a high swelling ability in an aqueous solution. The swelling of hydrogels were achieved a maximum degree and diameter of 270 and 63mm in water, respectively. The swelling behavior of these hydrogels was investigated to determine function of the effect of pH and polymeric compositions.