Preparation of Poly(AA-AM) Water Superabsorbent by Inverse Microemulsion Polymerization

A copolymer superabsorbent was prepared by inverse microemulsion polymerization, using cyclohexane as the continuous phase, water as the dispersed phase, N,N-methylene bisacrylamide as the crosslinking agent, ammonium persulfate (APS) as the initiator and OP-10 and SDS as complex surfactants. The synthetic variables (amount of crosslinking agent and initiator, water/oil ratio, monomer/surfactant ratio, and AA/AM ratio), and their effects on the absorbencies of the synthesized superabsorbents were studied. The relationships between the water absorbency and absorption time as well as the water retention capacity of the water superabsorbent were studied. The experimental results of superabsorbent polymers (SAPs) showed the maximum water absorbency of 1432 g/g, and the water absorbency of 722 g/g within 15 min. The water retention in the soil was greatly enhanced using the above superabsorbents. SEM indicated an irregular, undulant, and microporous surface of the superabsorbent, which was convenient for the penetration of water into the polymeric network. SAPs can be considered for water-managing materials for agriculture and horticulture purposes in desert and drought-prone areas. (C) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 110: 3859-3864, 2008