Yun, JP Park, YH Lee, S Park, KH Lee, CJ 2024-01-21T09:12:03Z 2024-01-21T09:12:03Z 2022-01-10 2003-03 0379-153X https://pubs.kist.re.kr/handle/201004/138781 For the purpose of obtaining surface-anionized poly(vinyl alcohol) (PVA) hydrogel beads, vinyl acetate(VAc) and methacrylic acid(MAA) were copolymerized by the suspension polymerization technique and followed by the saponification. It was confirmed by H-1-NMR that the copolymerized microspheres contained carboxylic acid groups in their surface. poly(VAc-co-MAA) microspheres were completely saponified in the heterogeneous system. The saponification reaction was faster than that of PVAc microspheres. We observed the swelling property of saponified PVA microspheres treated in the acidic solution and in the alkaline solution successively. Saponified microspheres shrank in acidic solution and swelled in alkaline solution respectively, which was reversible. From the result, saponified microspheres were highly water-absorbing hydrogel beads and were certified -COOH group at their surface by H-1-NMR and FT-IR. Korean POLYMER SOC KOREA COPOLYMER MEMBRANES Preparation of surface-anionized poly(vinyl alcohol-co-methacrylic acid) hydrogel beads Article 1 POLYMER-KOREA, v.27, no.2, pp.159 - 166 POLYMER-KOREA 27 2 159 166 scie scopus kci ART000900256 000181989700010 2-s2.0-33644660182 Polymer Science Polymer Science Article COPOLYMER MEMBRANES poly(vinyl alcohol) poly(methacrylic acid) microspheres saponification hydrogel