γ-环糊精对二甲戊灵的包合作用

以γ-环糊精(γ-CD)为主体, 采用饱和水溶液法对客体二甲戊灵进行包合. 采用紫外光谱以等摩尔连续变化法确定包合物的包合比为1∶1; 红外光谱证明二甲戊灵的部分苯环结构可能进入了γ-CD的空腔; 热分析结果证明包合作用提升了二甲戊灵的熔点; 粉末X射线衍射谱图中新衍射峰的出现说明形成了新物相; 扫描电镜则直观展现了包合物的外观. 以上结果均表明形成了γ-CD-二甲戊灵包合物, 其包合平衡常数K=1123.99 L/mol. 包合作用使二甲戊灵的熔点从54 ℃升至75 ℃, 溶解度提高了约11.5倍, 包合物热贮稳定性达标, 为进一步将其加工成其它水基化农药剂型提供了可能.

Inclusion Complexes of γ-Cyclodextrin with Pendimethalin†

Through the saturated water solution method, the guest body pendimethalin was tried to be inclu-ded by the host body γ-cyclodextrin(γ-CD). Ultraviolet spectrum was used to determine the inclusion ratio in accordance with the Job’s method, clarified that the inclusion molar ratio was 1∶1. Infrared spectrum proved that the benzene ring structure of the pendimethalin could be entered into the γ-CD’s hydrophobicity cavity. The melting point of the pendimethalin was proved to be increased after the inclusion by thermal analysis. The emergence of the new diffraction peaks in powder X-ray diffraction atlas was attributed to the formation of new phase. The appearance of the inclusion was intuitively showed by the scanning electron microscopy(SEM). All of the results above indicated that the γ-CD-pendimethalin inclusion complex were obtained, and the equilibrium constant K was 1123.99 L/mol. Both the melting point and the solubility of the pendimethalin were significantly improved by including, therefore, pendimethalin could be processed into water-based pesticide formulations in the form of the inclusion.