丙烯酸-丙烯酰胺的反相悬浮聚合及吸水性能的研究

THE PREPARATION OF HIGH WATER-ABSORBING POLY (SODIUM ACRYLATE-ACRYLAMIDE) BY INVERSE SUSPENSION POLYMERIZATION

以环己烷为连续相,十六烷基磷酸单酯为悬浮稳定剂,N,N＇-亚甲基双丙烯酰胺为交联剂,过硫酸盐为引发剂,采用反相悬浮聚合法合成了高吸水性丙烯酸钠-丙烯酰胺交联共聚物。研究了共聚物吸水性能与交联剂、引发剂用量、丙烯酸中和度、共聚单体组成、水中所含电解质浓度以及共聚物粒度的关系。制得的共聚物吸去离子水可达700g/g以上,吸0.9％NaCl溶液70g/g以上。

The high water-absorbing resins consisting of crosslinked acrylamide, acrylic acid and its sodium sait copolymer (PAM-PAA-PAANa) were prepared by inverse suspension polymerization. The advantage of our method gets rid of evaporating solvent and dispersing medium, the granular products may be obtained directly by filtering. The water-absorption power of the resins were determined. In the polymerizing reaction system, water soluble monomers were polymerized by using potassium persulfate as initiator, cyclo-hexane as the continuous phase, N, N' -methylenebisacrylamide as the cross linking agent, and monohexadecyl phosphate as the dispersant. Under a fixed polymerization condition, the average particle size of dryed product was 100-350μm in diameter and decreases with increasing stirring speed and amount of dispersant used respectively. The effects of the amount of initaitor, crosslinking agent used, monomer composition and degree of neutralization on the water-absorption capacities of the copolymer were also studied. The experimental results show that the enchanced water-absorption power of the copolymer resin is notable, especially that in aqueous solution containing Ca2+, Mg2+, and Fe3+ comparing with the cross-linking homopolymer poly (sodium acrylate). The absorption amount of the resin can over 700g/g and over 70g/g in case of deionking water and 0. 9% Nad solution, respectively.