啶虫脒/希夫碱改性凹凸棒土缓释体系的制备与性能

Preparation and Properties of Slow-released System of Acetamiprid/Schiff Base Modified Attapulgite

摘要:

采用后接枝方法制备希夫碱铜离子配合物改性凹凸棒土（Cu2 -Sal-ATP），采用浸渍法制备啶虫脒/凹凸棒土（ATP）缓释体系。利用FTIR、XRD、N2吸附-脱附、SEM和DSC 对改性凹凸棒土的结构进行了表征，并探究了改性凹凸棒土对农药啶虫脒的吸附行为和缓释体系的释药行为。结果表明，啶虫脒是以非晶相存在于改性凹凸棒土中，药物装载未改变载体的结构。有机改性提高了凹凸棒土对药物的载药量，且经希夫碱铜离子配位改性体系的载药量最高，其吸附行为符合准二级动力学模型。希夫碱铜离子配位改性凹凸棒土载药体系的缓释效果优于相应的希夫碱改性凹凸棒土（Sal-ATP）体系，载药体系的释药行为可用Korsmeryer-Pappas动力学模型来描述。

Abstract:

Schiff base copper ion complex modified attapulgite (Cu2 -Sal-ATP) was prepared by post-grafting method. Acetamiprid loading into the pores of attapulgite(ATP) was performed by the immersion method. The modified Attapulgite were characterized by fourier transform infrared spectroscopy(FTIR), N2 adsorption-desorption, scanning electron microscopy(SEM), X-ray diffraction (XRD) and differential scanning calorimeter(DSC). The drug loading content and drug release kinetic were also systematically studied. The results showed that the loaded acetamiprid was apparently in amorphous form, and that the loading process did not change the structure of the carrier. The loading content of acetamiprid was increased with the organic modification of ATP, Cu2 -Sal-ATP has the highest loading content among the unmodified and organically modified ATP. The adsorption process for acetamiprid follows the pseudo-second-order kinetic model. The Cu2 -Sal-ATP/acetamiprid system exhibits better slow-release properties than schiff base modified ATP(Sal-ATP)/acetamiprid system, and their releasing curves could be described by Korsmeyer-Peppas equation.