SYNTHESIS OF WATER-ABSORBENT RESIN WITH HIGH SALINE-ABSORBABILITY AND PENETRABILITY BY INVERSE SUSPENSION COPOLYMERIZATION

A water absorbent resin with high absorbability in saline and high absorption rate was synthesized by inverse suspension copolymerization, with cyclohexane as continuous phase, AA and AMPS as monomers, stearic phosphate as dispersing agent, N,N mythylene bisacrylamide as crosslinker and APS(ammonium persulphate) as initiator The effects of monomers composition, copolymerization temperature, neutralization degree of AA( Dn ), initiator concentration, type and concentration of crosslinker and ratio of oil to water on the absorbability and absorption rate,and physical properties of the resin were studied When w (AMPS)=40%, c (MBAM)=1 62mmol·L -1 , Dn = 75%, c (APS)=24 70mmol·L -1 , T =65℃ and V (oil)∶ V (water)=1 5∶1 0, the absorbency of the resin is 264 ml ·g -1 and 1200ml·g -1 respectively for normal saline and distilled water, and the ultimate degree of absorption in deionized water will be approached within 15min It was found by thermal analysis that raising the link density would improve the water preservation of the resin