The Release Kinetics Research And Preparation Of Starch Based Slow-rese Mincrocapsule Fungicide

Starch, existing in the plant kingdom, is a natural organic polymer which isbiodegradable, renewable, resourceful and cheap. However, its stucture difficiency andproperty defects restrict its application field. Therefore, the human beings create thestarch degeneration technology based on its characteristic in structure and property forbetter service.This topic studies in starch degeneration by graft copolymerization method. That is,under the enviroment of benzoyl peroxide, heating to85℃,the grafting rate is up to23.6%while do graft copolymerization by mixing starch and butyl acrylic monomersaccording to3:2ratio.The mechanical properties of modified starch completely meet thestandard of making Microcapsules Wall Material,so do the film forming and pencilrigidity.The satisfactory results also have been obtained in its hygroscopicity anddegradability. By seperating the modified starch and its carbendazim,we get pesticidemicrocapsule as well as active ingredient release law in PH buffer solvent:at the theinitial stage,when in the PH=9buffer solvent the active ingredient releases slowly whilein PH=4and PH=7buffer solvent releases quickly;at the late stage, the active ingredientrelease is incresed sharply when in PH=9buffer solvent, the released quantity achieved41.01mg,and in PH=7buffer solvent, the released quantity is up to115.20mg. As oresult of that, the microcapsule can released in different PH condition and through theabove experiments.