| Starch microspheres as a new type of functional polymer microspheres,it has been extensively and practically used as targeted drug carrier in the medical field. Starch microspheres can also be used as an absorbent and embedding agent to absorb or embed other substances,and it can achieve control-released effect. It can also be broadly used in metal ions adsorption separation or wastewater treatment. Composing starch with other materials(such as CD etc)to prepare microspheres usually was considered much better than single material.The composite starch microspheres was prepared by inverse-suspension polymerization with soluble starch as the main material at the same time adding a certain amountβ-cyclodextrin(β-CD),as the water phase after pasting,and soybean oil as oil phase,Span60 and Tween60 mixture as emulsifier,epichlorohydrin as cross-linked agent,and with the adsorption capacity of Methylene Blue as an index,the adsorption effect were investigated by starch concentration, starch andβ-cyclodextrin weight ratio, oil-water volume ratio and the amount of the cross-linking agent. The Preparation Technology of starch microspheres were optimized by a single factor experiment , Box-behnken experimental design and response surface methodology. The predicted model of the quadratic polynomial regression equation were optimumed: Y=5.41+0.074x1-1.08x2-0.43x3-0.098x4-0.11x1x2+0.19x1x3-0.44x1x4-0.67x2x3-0.14x2x4-0.43x3x4-0.83x12-1.29x22-0.71x32-0.80x42The optimum conditions was obtained as follows:starch concentration(x1)15.09%(the total amount of starch &β-CD was 3.018g in 20mL),starch &β-CD weight ratio(x2) 2.62:1,oil-water volume ratio(x3)3.84:1(the amount of oil was 76.8mL) and the amount of the cross-linking agent(x4)6.13mL.The microspheres morphology characterization,spectral,physical and chemical properties were analyzed by SEM,IR and other means. The result showed that it was a ball spherical shape,more regular shape,rough surface,with a larger surface area,and the diameter of microspheres in SEM was about 20μm;starch had success with the role of cross-linking agent,crosslinked starch microspheres reduced the solubility,and was still in the boiling water bathsolution,this also showed that crosslinking reaction occurred at least part of the starch and crosslinking agent;swelling test showed that crosslinking may be inhibited from swelling.The adsorption behavior of kiwifruit fragrance by composite starch microspheres which were used as a carrier was studied,and the release behavior and its kinetics of the obtained controlled-released fragrance compounds were also characterised .The results showed that the better adsorption condition of kiwifruit fragrance was the concentration of fragrance 7%,reaction time 2h,35℃,under these conditions,the adsorption capacity of kiwifruit fragrance was 540.3μL/g. And the fragrance compounds can achive a nice control-released effect in 3 days.There were two stages in the release of the control-released fragrance compounds:the initial release stage of microsphere surface and post-release of micropore phase,the release experiments also found that the former stage meets with classâ… k inetic process,and the latter meets with classâ…¡k inetic process.The adsorption behavior of Cu2+ and its kinetics model of the adsorption behavior were studied also.The results showed that in 120min the compound starch microspheres could reach the adsorption equilibrium state,the static adsorption experiment founded that at pH 6,35℃,0.10mol/L(initial concentration of Cu2+)the adsorption capacity of Cu2+ was higher. And the adsorption behavior may follow pseudo-second order kinetics model well,the adsorption process may be jointly controlled by a variety of mechanisms.
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