title: Addition of modified bentonites in polymer gel formulation of 2,4-D for its controlled release in water and soil.
abstract: Carboxymethylcellulose (CMC) gel was used for encapsulating anionic herbicide 2,4-D for its controlled release. The slower release rate of 2,4-D in water and soil was obtained by adding in the gel formulation some modified bentonites, which were prepared by intercalating inorganic or organic cations in interlayers of Na(+)-saturated bentonite. The higher encapsulation efficiencies of 2,4-D were observed on the bentonite/CMC gel formulations due to the sorption of 2,4-D on modified bentonites. The time taken for 50% of 2,4-D to be released in water, t(50), showed a variation (8.8-19.8 h) for these gel formulations, the largest value corresponding to the formulation incorporated with hydroxy-iron intercalated bentonite that has the highest sorption capacity to 2,4-D. The gel formulations could also control the release of 2,4-D when applied to a thin soil layer and demonstrated potential to reduce leaching of such anionic herbicides in soil.
authors.affiliation: Department of Chemistry, Shaoxing University, Zhejiang 312000, China. ljf@zscas.edu.cn
authors.forename: Jianfa
authors.initials: J
authors.lastname: Li
authors.forename: Man
authors.initials: M
authors.lastname: Jiang
authors.forename: Huan
authors.initials: H
authors.lastname: Wu
authors.forename: Yimin
authors.initials: Y
authors.lastname: Li
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000008:administration & dosage* / Q000737:chemistry; D000327:Adsorption; D001546:Bentonite / Q000008:administration & dosage* / Q000737:chemistry; D002266:Carboxymethylcellulose Sodium / Q000008:administration & dosage; D003692:Delayed-Action Preparations / Q000008:administration & dosage; D005782:Gels / Q000008:administration & dosage / Q000737:chemistry; D006540:Herbicides / Q000008:administration & dosage*; D012987:Soil / Q000032:analysis; D012995:Solubility; D014867:Water / Q000737:chemistry
chemical_list: D003692:Delayed-Action Preparations; D005782:Gels; D006540:Herbicides; D012987:Soil; D014867:Water; D001546:Bentonite; D015084:2,4-Dichlorophenoxyacetic Acid; D002266:Carboxymethylcellulose Sodium