文献类型：期刊文献

英文题名：Carboxylmethylcellulose/Bentonite Composite Gels: Water Sorption Behavior and Controlled Release of Herbicide

作者：Li, Jianfa[1];Lu, Jinhong[1];Li, Yimin[1]

机构：[1]Shaoxing Univ, Dept Chem, Shaoxing 312000, Zhejiang, Peoples R China

年份：2009

卷号：112

期号：1

起止页码：261

外文期刊名：JOURNAL OF APPLIED POLYMER SCIENCE

收录：SCI-EXPANDED(收录号：WOS:000263332200031)、、EI(收录号：20091612038598)、Scopus(收录号：2-s2.0-64249104423)、WOS

语种：英文

外文关键词：cellulose; clay; hydrogel; controlled release; herbicide

外文摘要：The composite gels were prepared by adding bentonite or its acid-activated derivative into the carboxylmethylcellulose (CMC) gel, and the resulted products were characterized with infrared spectroscopy. Different from ordinary swellable hydrogels, the CMC/bentonite hydrogel beads shrinked in water. The water sorption of dried gels was limited below 120% of their own weight, and a sorption equilibrium reached quickly within 20-40 min. The water of swollen gels exists mainly in bound status according to the DSC analysis. The release experiments in water were carried out to evaluate the release of herbicide metolachlor from gel formulations. The release mechanism dominated by a Fickian diffusion might be related to the quick and limited swelling of dried gels. Addition of bentonites in CMC gel is beneficial for slowing the release of metolachlor, especially when the acid-activated bentonite was added. The time taken for 50% of metolachlor to be released, t(50) was prolonged to 158 h for the composite gel formulation based on acid-activated bentonite from the 61.1 h for pore CMC gel formulation. (c) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 112: 261-268, 2009