Study On Sustained-release Insecticide With Fertilizer Of Chlorhexidine Benzamide Microcapsules

In this study,chlorantraniliprole microcapsules were prepared by in situ polymerization and melamine resin as wall material.On this basis,sustained-release insecticide with fertilizer of chlorantraniliprole microcapsules were prepared.In the process of prepare microcapsules;the best technological conditions to prepare melamine resin microcapsule were studied,chosen the optimum wall material and core material ratio.Study on factors to effect the formation of chlorantraniliprole microcapsules below:the type and the optimum preparation process of the precursor oil phase,the shear rate and the shear time of the microcapsules,the pH value of the polycondensation reaction system and the temperature of the polycondensation reaction.Evaluated the microcapsules and insecticide with fertilizer microcapsules,the decomposition rate,entrapment efficiency and drug loading of chlorantraniliprole microcapsules and microcapsules were determined.The optimal ratio of melamine and formaldehyde was 1/2.0,use melamine 6.8 g and formaldehyde solution 13.6 g,after mixing;the mixture was adjusted pH value to 8.0-9.0 with 10%sodium hydroxide solution.At 70 ? water bath temperature,stirring at 200r/min during 10min,obtained transparent fonnaldehyde-urea prepolymer solution.Preparation of microcapsule suspension:Use chlorantraniliprole 5.2 g and 25 g the mixture of dispersing solvent(S-200:S-150:5#mineral oil = 3.5:2:7),after mixing,adding emulsifier 500-LQ 2.0 g,Sanding to the original particle size D90? 5?m out of the oil phase;deionized water as the water phase.Add water 20g,the emulsification rate of 15000 rmp,high shear 6 min to form a stable O/W emulsion.The prepolymer solution mix with the emulsion under constant temperature magnetic stirring,stirred for 10 min,adjust the pH value to 4.6 with concentrated hydrochloric acid,heated as 0.5 ? to 1?/min to the optimum curing reaction temperature,50 ?,and incubated for 70 min,add 25%ammonium chloride solution 4 g,continue to react for 30min,then add wetting and dispersing agent 4g(pertoAA:D-110 = 1.0:3.0),add water to 100 g,prepared a uniform particle size,smooth surface,high encapsulation efficiency microcapsule Suspension.The optimum chromatographic condition is 220 nm and the mobile phase is(methanol:water)= 65:35,the peak shape is the best,and the separation is the highest,and peak time is about 7.436min,and the recovery rate is 99.04%-100.54%.The encapsulation efficiency of microcapsules is 90.70%and the drug loading is 9.22%.30 days can be achieved evenly release,can be added in the fertilizer to achieve the application requirements of sustained release.The stability of chlorantraniliprole microcapsule suspension and microcapsule dry powder at room temperature and thermal condition were tested.,the results showed that chlorantraniliprole was degraded 0.9%and 2.18%respectively after heat storage.The results showed that chlorantraniliprole microcapsules liquid or dry powder storage stability is good.The microcapsule suspension liquid was centrifuguged and filtered into microcapsule powder,combined with the selected compound fertilizer to prepare 0.1%chlorantraniliprole microcapsule insecticide with fertilizer granule.After storage at regular temperature for 6 months and heat storage for 14 days,the encapsulation efficiency and the drug-holding rate were decreased,the encapsulation efficiency of chlorantraniliprole was 63.1%and 53.2%,respectively.The results showed that the storage stability of low-content microcapsules need to further improvement,the stability of microcapsule sustained-release insecticide with fertilizer needs to be systematically selected in combination with the fertilizers-only used.The results of the consequent of the performance of the insecticide with fertilizer show that the heat stability of the drug is not ideal.The results of greenhouse plant test showed that 0.1%chlorantraniliprole microcapsule sustained-release insecticide with fertilizer had 10 g.ai/mu and 20 g.ai/mu,in other words,the preparation dosage is 10kg and 20kg.The sugarcane borers were fed with sugarcane stalks,which use 0.1%chlorantraniliprole microcapsule insecticide with fertilizer granule 20 days later,3 days later,the result showed the control effect on sugarcane borer was 77.37%and 93.32%respectively,generally,there was no borer harm.The field experiments of cowpea,tomato,cucumber show that,chlorantraniliprole was transmitted in plants by transpiration,chlorantraniliprole transmit in the cowpea and tomato is better,especially in the leaf.The pest control of cowpea and tomato persistence can reach nearly 1 month,and in the pods and the fruit,the residue is lower,will not cause excessive residues.The study also found that chlorantraniliprole transmit in cucumber is poor,it prove that the application of chlorantraniliprole microcapsule insecticide with fertilizer granule need to be applied to suitable crops,and exert its utmost value.