哒螨灵-层状双金属氢氧化物杂化物的合成及表征

在乙醇-水混合溶剂中采用共沉淀法将非离子型疏水性农药哒螨灵插入镁铝层状双金属氢氧化物(layered double hydroxides,LDHs)层间,制备出哒螨灵-LDHs杂化物。依据哒螨灵分子大小和杂化物的层间通道高度推测,哒螨灵分子是沿长轴方向与层板成一定倾斜角度以单层方式排列于LDHs层间。释放动力学研究表明,释放过程符合准二级动力学方程,LDHs颗粒内扩散是释放控制步骤;哒螨灵-LDHs杂化物具有明显的农药缓释性能,有望成为一种新型农药缓释剂。

Synthesis of pyridaben-layered double hydroxides hybrids using coprecipitation method

A non-ionic and poorly water-soluble pesticide, pyridaben, was intercalated into the gallery of layered double hydroxides (LDHs) using coprecipitation method in ethanol-water mixed solvent medium, obtaining pyridaben-LDHs hybrids. According to the gallery height of pyridaben-LDHs and sizes of pyridaben molecule, a probably morphology of pyridaben molecules in the gallery of LDHs was suggested that pyridaben molecules arranged as monolayer with the long axis tilted to the LDHs layers. The release kinetics of pyridaben from the hybrids was investigated in ethanol-water solution, and it was found that the release process may fit to the pseudo-second-order release kinetics and the diffusion through the LDHs particle of pyridaben played an important role in controlling the drug release rate. The hybrids could control the release of pyridaben, showing that the hybrids will be a potential pesticide controlled-release formulation.