| Abstract: | A novel superabsorbent composite from acrylamide (AM) and attapulgite (APT), polyacrylamide/attapulgite (PAM/APT), was prepared by polymerizing AM with the existence of APT in aqueous solution, and then saponified with NaOH solution. Considering the impacts of hydrophilic groups (? COONa, ? COOH, and ? CONH2) on properties of the PAM/APT composite, the effects of saponification mode, molar ratio of NaOH to AM and saponification time on water absorbency, hydrophilic group content, and surface morphology were investigated systematically. The results indicate that the two‐step adding NaOH mode is superior to that of the one‐step mode. Among the superabsorbent composite incorporated with 30 wt% APT, the composite saponified at 95°C for 2 h with the molar ratio of 0.6 for NaOH to AM acquired the highest water absorbencies of 1715g g?1 and 87.8g g?1 in distilled water and in 0.9 wt% NaCl solution, respectively. The molar ratio of various hydrophilic groups at this time was 10:3:11 for ? COONa, ? COOH, and ? CONH2 determined using linear potentiometric titration method. POLYM. ENG. SCI. 46:1762–1767, 2006. © 2006 Society of Plastics Engineers. |
