[Study on the stability of pesticide WDG suspension by TURBISCAN LAB].

ABSTRACT

TURBISCAN LAB has been applied to analyze the stability of pesticide WDG (water dispersible granule)suspension. With the application of poly (styrene sulfonic acid -co- acrylic acid) sodium salt dispersant made by ourselves in a formula of 75 wt% tribenuron WDG, and by measuring the change in the intensity of transmission and backscattering light in pesticide WDG suspension with time, the dynamic sedimentation process of pesticide WDG suspension with time can be described in-situ, reflecting the stability of pesticide suspension system. It was found that when the contents of polymer dispersant were about 6 wt% in the WDG, and the average molecular weight was about 15 000, the stability of WDG suspension system was relativelygood. Through studying the thickness of sedimentation, the settling rate of particles, the particle size, and the increasing rate of particle diameter in the suspension system in various kinds and contents of polymer dispersant, it has been made more convenient and efficient to sift the accessory ingredient in the formula of dosage form as well as to optimize the formula of pesticide WDG.