文献类型：期刊文献

英文题名：Controlled release of herbicide acetochlor from clay/carboxylmethylcellulose gel formulations

作者：Li, Jianfa[1];Li, Yimin[1];Dong, Huaping[1]

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

年份：2008

卷号：56

期号：4

起止页码：1336

外文期刊名：JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

收录：SCI-EXPANDED(收录号：WOS:000253321200025)、、Scopus(收录号：2-s2.0-40549104081)、WOS

语种：英文

外文关键词：acetochlor; controlled release; clay; carboxylmethylcellulose; gel

外文摘要：Controlled-release formulations of the herbicide acetochlor were prepared by using carboxylmethylcellulose (CMC) gel and different types of clay, which were obtained by acid activation, pillared with metal hydroxides, or saturated with organic cations. The effect of formulation parameters (amount and type of clay used, cross-linking time, and drying of the hydrogel formulations) on the acetochlor release rate from different formulations was evaluated by water-release studies. The time taken for 50% of acetochlor to be released, t(50), showed a wide variation (151 -522 h) for dried gel formulations, the largest value corresponding to the formulation incorporating aluminum hydroxide pillared clay into CMC gels. The release rate of acetochlor from clay/CMC hydrogel formulations decreased with the increase of the hydrogels' cross-linking time (t(50) values ranged from 2.18 to 14.0 h for cross-linking times ranging from 2.0 to 120 min). The performance of inorganic clays in dried gel formulations on slowing the release of acetochlor is related to their sorption capacities, but the addition of organic clay did not lead to the slowest release despite its highest sorption capacity. According to the parameters of an empirical equation used to fit herbicide-release data, the release of acetochlor from clay/CMC gel formulations is controlled by diffusion mechanism.