Synthesis of Superabsorbent with High Absorbability in Saline

A superabsorbent of poly(sodium acrylate) was prepared by inverse suspension polymerization with polyhydric alcohol as crosslinking agent,NP-SP(sodium alkyl phosphate-Span) as multiplex suspension stabilizer,AA(acrylic acid)as monomer,APS(ammonium persulphate) as initiator and cyclohexane as continuous phase.The parameters which affect the physical properties and absorbability in normal saline of the product and stability of the system were studied,such as the type and mass concentration of crosslinker,the type,mass concentration and mass ratio of stabilizer,the concentration of initiator,the neutralization degree of monomer (mol percent of neutralized AA in monomer) and the reaction temperature.When ρ(crosslinker)=0.53 g/L,ρ(NP-SP)=0.008-0.01 g/mL,m(SP)∶m(NP)=(2.3-4.0)∶1.0,c(APS) =40.5 mmol/L,neutralization degree of monomer x(sodium acrylate)=79.2%,and polymerization temperature was 70-76 ℃,the polymerization system was stable,the product was of proper particles,and the absorbabilities in normal saline and distilled water were 199 mL/g and 864 mL/g respectively.This resin is superior to other crosslinked products in absorbability in normal saline.