| Abstract: | A series of xerogels based on sodium acrylate, nonionic monomers such as 2‐hydroxyethyl methacrylate (HEMA) and poly(ethylene glycol) methacrylate (PEGMA), and N,N′‐methylene bisacrylamide were prepared by inverse suspension polymerization. The results indicate that the water absorbencies for these two gel series were effectively improved by the addition of a small amount of nonionic monomer (HEMA or PEGMA). The initial absorption rates in deionized water were faster for the PEGMA gels than for the HEMA gels. Scanning electron microscopy showed that the spherical particle size was smaller for the PEGMA gels than for the HEMA gels. In addition, the water absorbency of the gels in various salt solutions decreased with increasing ionic strength, especially for the multivalent salt solutions. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3666–3674, 2004 |
