Study On The Preparation And Stability Of 35% Nicosulfron·Mesotrione·Atrazine OD

In 2015,the introduction of "zero growth" to a certain extent affected the future direction of pesticide industry development,the original medicine into the micro-profit period,the preparation industry growth rate slowed.At the same time,environmental friendliness remains the development theme of pesticide formulations.The development of pesticide preparation technology and process upgrading has become a hot topic.Pesticide preparations need to pay attention to new technology,new application,real innovation,need to be refined step by step,pesticide dispersible oil suspension has more advantages over other traditional dosage forms because of its high efficiency,safety,economy and environmental friendliness.However,the stability of the pesticide dispersible oil suspension has been restricting the development of the preparation for a long time.In this paper,the compounds of Nicosulfron,mesotrione and atrazine were used as research carriers.on the basis of screening 35% Nicosulfron·mesotrione·atrazine dispersible oil suspension(OD),the influence of different factors on the stability of emulsification dispersion and rheological behavior of dispersed oil suspension system in water was systematically studied,and its related mechanism was discussed.The emulsifier suitable for methyl oleate was successfully prepared and applied as emulsifier to the pesticide oil suspension for the first time.The thixotropy mechanism in Nicosulfron·mesotrione· atrazine dispersible oil suspension was investigated.The main findings are as follows:1.In this paper,35% Nicosulfron·mesotrione·atrazine dispersible oil suspension was prepared by using methyl oleate as carrier,among which emulsifier and wetting dispersant were the key to formula screening.1)The optimum process parameters are determined,the zirconia beads commonly used in the industry are selected as the grinding medium,and the self-made compound emulsifier is selected in the experiment,the amount added is 15%,the sample is prepared by sanding without adding other components,and the particle size is measured by sampling at different times.the screening sanding time of 150 min was the most reasonable.2)According to the previous emulsifier screening studies,the possibility that the emulsifier can emulsify methyl oleate when the HLB value is around 12 is more likely,and the principle of compounding anion and anion,anion and non-ion should also be followed,and the infrared structure of self-made emulsifier is analyzed according to the principle of minimum dosage,which is similar to the chemical structure of methyl oleate.The final choice of SR-08 and 500# dosage of 15% is the most appropriate.3)A series of block polyethers(L61~L65)with propylene glycol as the starting agent were selected as dispersants.The particle size data,viscosity and dispersion of L64 were clearly screened by cold and hot storage at room temperature.Finally determine L64,the dosage of 1% is the most appropriate.4)The main viscosity regulators used in the production of Nicosulfron· mesotrione·atrazine dispersible oil suspensions have been reported to be mostly organic bentonite.In this paper,three kinds of organic bentonite were selected as the research objects.the organic bentonite(zhejiang)was selected as the structural stabilizer of the preparation with a dosage of 1.5%.5)The screening of its stabilizers mainly ensures that the decomposition rate after thermal storage is less than 5%.2.The effects of different dispersants and organic bentonite on the rheological properties and thixotropy of 35% Nicosulfron·mesotrione·atrazine dispersible oil suspension were studied.The results show that:1)The apparent viscosity of 35% Nicosulfron·mesotrione·atrazine dispersible oil suspension system decreases gradually with the increase of shear rate,showing the phenomenon of shear dilution,which is characterized by pseudoplastic fluid,which accords with Herschel-Buckley rheological model.2)The addition of organic bentonite(Zhejiang)does not change the rheological type of oil suspension,but has a significant effect on viscosity and rheological parameters of the system.With the addition of organic bentonite,the network structure can be formed and the yield value and consistency index of the system become larger.