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以木薯淀粉为主要原料,环氧氯丙烷为交联剂,CS2为酯化剂,过硫酸铵/亚硫酸氢钠为引发剂,丙烯酰胺和丙烯酸为接枝单体,经交联-酯化-接枝制得交联型木薯淀粉黄原酸酯-g-AA/AM,进一步采用反相乳液聚合法得到复合变性淀粉微球。考察了诸因素对合成的影响,确定的较佳工艺条件为:酯化反应的m(NaOH)∶m(干基淀粉)=0.08∶1.00,m(CS2)∶m(干基淀粉)=0.882∶1.000,酯化时间4h,酯化温度35℃;接枝反应的m(单体)∶m(干基酯化淀粉)=0.8∶1.0,引发剂浓度0.289mol/L,接枝温度35℃,接枝时间3.5h。采用红外光谱、扫描电镜、X-射线衍射和热重分析对交联型木薯淀粉黄原酸酯-g-AA/AM微球进行了表征。通过对含铬废水的吸附研究表明,交联型木薯淀粉黄原酸酯-g-AA/AM微球对铬(Ⅵ)的去除率可高达97%以上。
Using cassava starch as main raw material, epichlorohydrin as cross-linking agent, CS2 as esterification agent, ammonium persulfate / sodium bisulfite as initiator, acrylamide and acrylic acid as grafting monomer, - graft cross-linked cassava starch xanthate-g-AA / AM, and further use of inverse emulsion polymerization obtained composite modified starch microspheres. The effects of various factors on the synthesis were investigated. The optimum technological conditions were as follows: m (NaOH): m (dry basis starch) = 0.08:1.00, m : 1.000, the esterification time is 4h and the esterification temperature is 35 ℃. The graft reaction m (monomer): m (dry esterified starch) = 0.8:1.0, initiator concentration 0.289mol / L, graft temperature 35 ℃ , Grafting time 3.5h. The crosslinked cassava starch xanthate-g-AA / AM microspheres were characterized by infrared spectroscopy, scanning electron microscopy, X-ray diffraction and thermogravimetric analysis. The adsorption of Cr (Ⅵ) on wastewater containing chromium showed that the removal rate of chromium (Ⅵ) by cross-linked cassava starch xanthate-g-AA / AM microspheres was as high as 97%.