交联羧甲基瓜尔胶的制备

Study on preparation of cross-linked carboxymethyl guar gum

以植物瓜尔胶为原料、环氧氯丙烷为交联剂、氯乙酸为羧甲基化试剂,制备了交联羧甲基瓜尔胶。研究了环氧氯丙烷的用量、氯乙酸的用量、氢氧化钠的用量及反应温度对产品取代度的影响;考查了产品糊的耐温性能,并用FT-IR对产品的结构进行了表征。实验结果表明:配料质量比瓜尔胶∶环氧氯丙烷∶氢氧化钠∶氯乙酸为1.00∶0.015∶0.45∶0.40,反应温度50℃时,产品的取代度达最高0.340。FT-IR分析结果表明,瓜尔胶分子中引入了羧甲基基团,交联羧甲基瓜尔胶成功制备。与原瓜尔胶糊相比,产品糊的耐温性能得到改善。

With natural guar gum as material,epichlorohydrin as cross-linking agent,chloroacetic acid as carboxymethylating agent,cross-linked carboxymethyl guar gum was prepared. The effects of epichlorohydrin dosage,chloroacetic acid dosage,sodium hydroxide dosage,and reaction temperature on the degree of substitution of product were studied. The temperature resistance of product paste was also investigated. The maximum degree of substitution of product of 0.340 was obtained under the following conditions： the mass ratio of guar gum ：epichlorohydrin ：sodium hydroxide ：chloroacetic acid 1.00：0.015：0.45：0.40,reaction temperature 50℃. The FT-IR results showed that the group of carboxymethyl had introduced to the product,and crosslinked carboxymethyl guar gum was successfully prepared. Product paste had improved temperature resistance in contrast to native guar gum paste.