混合介质中羟乙基纤维素的阳离子化反应

摘要

在乙醇(Et.)和异丙醇(iPA)混合介质中,采用3-氯-2-羟丙基三甲基氯化铵(CTA)为醚化剂进行了羟乙基纤维素(HEC)的活化.阳离子化反应,对影响产物阳离子化取代度(Cds)和阳离子化效率(Cre)的因素进行了研究,并采用<'1>H NMR对产物的结构进行确认.结果表明,按m(HEC):m(Et.):m(iPA):m(25%NaOH):m(69%CTA):m(Ea)=20:20:70:13:15:8的配比,25℃时用胺碱活化30 min,60℃恒温反应4 h,产物的Cds为0.50,Cre达到75%.%In the mixed solvents of ethanol and isopropanol, 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CTA) was used as etherifying agent to achieve the cationic reaction of hydroxyethyl cellulose ( HEC ) . The factors affecting the degree of substitution ( Cds ) and reaction efficiency (Cre ) were investigated, and the structure of the product was identified by 1H NMR. Cds of the product was 0.50 and the Cre reached 75％, with mass ratio m(HEC)∶m(Et.)∶m(iPA)∶m(25％NaOH)∶ m(69％CTA): m(Ea)= 20 ∶ 20 ∶ 70 ∶ 13∶ 15∶ 8, at 25 ℃ for 30 min activation with amine, and reaction at 60 ℃ for 4 h.