吡唑醚菌酯悬浮剂流变性与稳定性的关系研究

Study on the Relationship between Rheology and Stability of Pyraclostrobin Suspension Concentrate

吡唑醚菌酯因其熔点低、晶型多,其悬浮剂在贮存过程中易出现膏化、析晶的现象。本文通过使用4种原药产品、3种助剂产品制备得到12个25%吡唑醚菌酯SC样品,在25℃下,测试其基本理化性能,并通过高级流变仪测定其流变曲线、屈服应力、触变性、G′/G"-γ曲线、G′/G"-ω曲线、|η*|/tanδ-ω曲线、η-T曲线等。试验结果表明,流变曲线、触变性测试结果可以反映吡唑醚菌酯SC的部分物理特性;G′/G"-γ曲线反映出吡唑醚菌酯SC的常温物理稳定性;G′/G"-ω曲线、|η*|/tanδ-ω曲线反映了吡唑醚菌酯SC倾倒、灌装过程中的流动性。由于吡唑醚菌酯低熔点的性质,η-T曲线可以更快、更直接地反映出吡唑醚菌酯SC在热贮后是否粒径增长、膏化变稠。本研究结果对吡唑醚菌酯SC的研发生产过程具有一定的指导意义。

Due to its low melting point and many crystal forms,pyraclostrobin is prone to creaming and crystallization in its suspension concentrate during storage.In this paper,12 kinds of 25%pyraclostrobin SC samples were prepared by using 4 kinds of pyraclostrobin technical drugs and 3 kinds of pesticide additives.Their basic physical and chemical properties were tested at 25℃.The rheological curve,yield stress,thixotropy,G′/G"-γcurve,G'/G"-ωcurve,|η*|/tanδ-ωcurve,η-T curve of 25%pyraclostrobin SC were tested with the modular compact rheometer.The test results showed the rheological curve and thixotropy test results could show some physical characteristics of pyraclostrobin SC.The G′/G"-γcurve reflected the physical stability of pyraclostrobin SC stored at normal temperature.The G'/G"-ωcurve and|η*|/tanδ-ωcurve reflected the fluidity of pyraclostrobin SC during pouring and filling.Due to the low melting point of pyraclostrobin,theη-T curve could quickly and directly reflect whether pyraclostrobin SC grows in particle size and became thickened after thermal storage.The findings had certain guiding significance in development and production of pyraclostrobin SC.