Preparation And Study Of Pyraclostrobine 35% SC

The pyraclostrobin belongs to strobilurin,and its major formulation are emulsifiable concentrate(EC)and suspension concentrate(SC).But because the melting point of pyraclos-trobin is low,it is easy to be found in sanding creaming and increasing particle size in devel?opment and production process.So the study focuses on the successful development process of 35%pyraclostrobin SC.First,the four types pyraclostrobin's melting point were measured by melting point detector and the IV pyraclostrobin was selected as experimental material,which the melting point was highest.Then we have carried out the screening test recipes of pyraclostrobine 35%SC using different wetting dispersant,thickening agent,anti-freezing agent,antifoaming agent,antiputrefactiva.The optimal formula of pyraclostrobin 35%SC is pyraclostrobine 35%,the aromatic polyether phosphate 4%,high-performance sulfonate 1.5%,xanthan gum 0.2%,aluminium-magnesium 1%,propylene glycol 4%,BIT antiputrefactiva 0.2%,antifoaming agent 0.3?0.5%,up to 100%by water.After that,all indexes should be determined to the products based on the homologous technique such as partical size,viscosity,pH,suspending rate,persistent foamability.The content of effective constituent should be measured by using HPLC.And then put the formulation into thermal storage experiment under the conditions of(54±2?)for 14d,considering all elements to confirm the best formula.SC has been made on the basis of the above best formula,and finally to measure Laboratory efficacy.Compared with a commercial suspension products with propiconazole,the study tests Laboratory efficacy of Pyraclostrobine 35%SC to Blumeria graminis(DC.)Speer.The maj or results are as follows:(1)Considering all factors,the best formula has been determined in the final time after formulation screening above.The optimal formula of pyraclostrobin 35%SC is pyraclostrobine 35%,the aromatic polyether phosphate 4%,high-performance sulfonate 1.5%,xanthan gum 0.2%,aluminium-magnesium 1%,propylene glycol 4%,BIT antiputrefactiva 0.2%,antifoaming agent 0.3?0.5%,up to 100%by water(2)We prepare pyraclostrobin 35%SC according to the best formula.And we also detect the quality indicators of pyraclostrobin 35%SC,the pyraclostrobin 35%SC accorded with the criterions and requirements of the SC.Indexes in certain heat reservoir(54±2?,14d)were suspensibility 98.2%,pH 6.5,resolution ratio 1.9444%.Toxicity test results showed that the toxicity of pyraclostrobin 35%SC to Blumeria graminis(DC.)Speer was below the toxicity of propiconazole to Blumeria graminis(DC.)Speer,and the toxicity of pyraclostrobin 35%SC to Blumeria graminis(DC.)Speer was 2 times as much as the toxicity of propiconazole to Blumeria graminis(DC.)Speer.The pyraclostrobin 35%SC could use to control Blumeria graminis(DC.)Speer.(3)The determination results of laboratory show that the effect of 35%pyraclostrobin suspension of wheat powdery mildew was higher than that of the control drug propicondzole,can be used to control this disease.