PREPARATION AND ABSORBENCY OF ACRYLIC ACID-ACRYLAMIDE SUPER ABSORBENTS BY SOLUTION POLYMERIZATION

Some superabsorbents(PAAAM)were prepared from copolymer of part-neutralized acrylic acid(AA)and acrylamide(AM) with potassium peroxydisulfate as initiator,N,N'-methylene-bis-acrylamide as crosslinking agent,by means of water solution polymerization.The polymerization conditions were optimized by orthogonal experiment method and single factor experiment method,and the absorbencies of PAAAM in distilled water and 0.9% NaCl solutions were regression-analyzed.The maximum absorbency of the superabsorbent in distilled water and 0.9% NaCl solution was 2 710 g/g and 133 g/g,respectively,when monomer concentration was 25%,mass ratio of acrylic acid and acrylamide was 6 ∶ 1,neutration of acrylic acid 60%,crosslinker concentration 0.01%,initiator concentration 0.1%,and reaction time 2 h,2 h and 3 h at 60℃,70℃ and 80℃,respectively.