화학공학소재연구정보센터
Journal of Applied Polymer Science, Vol.66, No.3, 499-507, 1997
Superabsorbent Polymeric Materials .4. Swelling Behavior of Cross-Linked Poly(Sodium Acrylate-Co-N,N-Dimethyl(Acrylamidopropyl) Ammonium Propane Sulfonate) in Aqueous Salt Solution
A series of xerogels based on sodium acrylate ( SA), N,N-dimethyl(acrylamidopropyl) ammonium propane sulfonate (DMAAPS), and N,N’-methylene bisacrylamide (NMBA) were prepared by inverse suspension polymerization. The water absorbency or swelling behavior for these xerogels in water or various saline solutions was investigated. Results obtained from this study revealed a water absorbency of 721 g H2O/g sample in deionized water and 83 g H2O/g sample in 0.9 wt % NaCl solution for a gel containing a 1.50 x 10(-2) molar fraction of DMAAPS. The absorbency in the chloride salt solutions decreased with an increase in the ionic strength of the salt. For the same ionic strength of various salt solutions, the swelling amount had the following tendency : Co2+ > Ni2+ > Cu2+ for the higher ionic strength of 2.44 x 10(-5)-1.8 x 10(-2) M. The Co2+, Ni2+, and Cu2+ solutions induce approximately the same degree of swelling at the lower ionic strength of <2.44 x 10(-5) M. The pH effect on the water absorbency for these xerogels was also investigated.