基于水凝胶体系的磷酸根响应控释农药释放行为分析  

Release Behavior of Hydrogel-based PO4^3--responsive Controlled Release Pesticide

作　　者：陈超文 刘彬 吴正岩[1] CHEN Chao-Wen;LIU Bin;WU Zheng-Yan(Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院合肥物质科学研究院,合肥230031 [2]中国科学技术大学,合肥230026

出　　处：《分析化学》2020年第11期1583-1589,共7页Chinese Journal of Analytical Chemistry

基　　金：中国科学院科技服务网络(STS)计划项目(No.KFJ-STS-QYZD-115)资助。

摘　　要：基于Fe^3+与羧甲基纤维素钠(CMC)的交联作用,制备了以凹凸棒土(ATP)为载体、吡虫啉(IM)为目标农药分子的基于水凝胶的磷酸根(PO4^3-)响应控释农药体系(PCRPH)。利用扫描电镜、X射线衍射等表征了PCRPH。结果表明,PCRPH与PO4^3-相互作用,主要发生溶胀和Fe^3+解离。随着PO4^3-浓度增大,PCRPH中分子间距增加并逐步解离,能有效促进内部IM分子向外扩散,实现农药的可控释放,提高农药利用率。释放动力学分析表明,IM在PO4^3-溶液中的释放过程属于Fickian扩散。此外,溶液中IM的释放量大小不受共存阴离子Cl-及pH值的影响,具有良好的稳定性,但提高温度能促进IM从PCRPH中释放。Phosphate anion(PO4^3-)-responsive controlled release pesticide based on hydrogel(PCRPH)was developed based on crosslinking effect between ferric ion(Fe^3+)and sodium carboxymethylcellulose(CMC).In PCRPH,attapulgite(ATP)was served as carrier for loading imidacloprid(IM).The scanning electron microscope(SEM)and X-ray diffraction(XRD)results demonstrated that PCRPH in PO4^3-solution might swell and disaggregate,which could be enhanced as the PO4^3-contents in solution increase.As a result,the controlled-release of IM inside hydrogel could occur so that the utilization rate of pesticide was improved.According to the release kinetics analysis,the release mechanism of IM from PCRPH was consistent with the Fickian diffusion law.The release amount of IM from PCRPH remained stable against the coexisting Cl-and different pH,whereas temperature displayed positive relation with the release rate of IM.

关 键 词：羧甲基纤维素钠 铁离子 凹凸棒土 吡虫啉 磷酸根离子 控释水凝胶 

分 类 号：TQ450.1[化学工程—农药化工]