阳离子化羟乙基纤维素醚的合成与溶液性质

以工业羟乙基纤维素(HEC)和N-(2,3-环氧丙基)三甲基氯化铵(GTA)为原料,在碱催化剂下干法制备不同取代度季铵盐型阳离子羟乙基纤维素醚。用均匀设计法优化合成条件,并通过蒙特卡罗模拟得到优化工艺条件,通过实验验证得到阳离子醚化试剂的反应效率达到85%以上,取代度达到0.49。同时探讨了阳离子羟乙基纤维素醚(QHEC)在不同介质中的黏性行为。结果表明,阳离子羟乙基纤维素醚在纯水中具有典型的聚电解质黏性行为,随着QHEC浓度减小,比浓黏度增大。同一QHEC质量浓度下,NaCl溶液中QHEC的比浓黏度总大于KCl溶液中QHEC的比浓黏度;随着外加盐NaCl溶液浓度的增大,其比浓黏度减小。

Preparation of quaternary ammonium alkyl hydroxyethylcellulose ether and properties of its aqueous solution

Quaternary ammonium alkyl hydroxyethylcellulose ether(QHEC)was prepared via a dry process of reaction of(hydroxyethylcellulose) and N-(2,3-epoxypropyl)-trimethyl ammonium chloride in presence of an alkaline catalyst.The optimum reaction conditions were obtained with tests under uniform experimental design and regression with Monte Carlo(Simulation).The results showed that the yield can achieve 85% with the degree of substitution achieves 0.49.Viscosity(behavior) of the aqueous solution of QHEC was studied and the results showed that it has the characteristics of typical poly-(electrolyte).The reduced viscosity increases as the concentration of QHEC decreases.The increase of additional salt(concentration) will decrease the reduced viscosity of the QHEC solution.At the same QHEC concentration,the reduced(viscosity) of the solution will be higher as NaCl is added than that as KCl is added.