糯小麦羧甲基淀粉的微波合成及性质研究

Studies on the properities and microwave synthesis of waxy wheat carboxymethyl starch

以中糯2号糯小麦淀粉为原料,采用微波辐射的方法进行糯小麦羧甲基淀粉的合成,分别考察了微波辐射时间、分散剂乙醇用量、NaOH用量、CH2ClCOOH用量四个因素对取代度的影响,实验结果表明,欲得到取代度大的糯小麦羧甲基淀粉可采取的工艺条件为:辐射时间2mim、乙醇用量为60ml、NaOH用量4.0g、一氯乙酸用量5.0g。采用红外扫描技术对其合成效果进行鉴定,在1602cm-1,1419cm-1和1328cm-1处出现-COO-的特征吸收峰。其中1602cm-1处为C-O的对称与不对称伸缩振动的吸收峰。表明已发生羧甲基化反应。并对所得糯小麦羧甲基淀粉的理化性质包括透明度、冻融稳定性、抗老化能力及抗生物降解能力进行研究。结果表明,微波合成糯小麦羧甲基淀粉具有高透明度、良好冻融稳定性、强抗老化能力及强抗生物降解能力等优良品质。

Using waxy wheat（zhongnuo2#）as material,waxy wheat carboxymethyl starch is prepared through microwave.The effect of Microwave irradiation time,ethanol consumption,NaOH consumption and CH2ClCOOH consumption on the degree of substitution was investigated.The experimental results show that a high degree of substitution will be acquired under the following conditions：irradiation time 2min,ethanol dosage of 60ml,NaOH dosage of 4.0g,CH2ClCOOH dosage of 5.0g.And the preparation results are analyzed by IR.We can observe that characteristic absorption peaks of-COO-appear in 1602cm^-1,1419cm^-1and 1328cm^-1,and the C-O absorption peak in1602cm^-1is formed by stretching vibration and antisymmetric stretching vibration,which shows carboxymethylation reaction is finished.The properities of waxy wheat carboxymethyl starch are also studied,the results shows that waxy wheat carboxymethyl starch are of good properities including higer clarity,freeze-thaw stability,stronger anti-aging ablity and anti-biodegradability.