A NEW METHOD OF PREPARING CATIONIC DERIVA TIVES OF POLYSACCHARIDES

The paper describes a new synthesis of cationic derivatives of polysac charides. Epichlorohydrin is reacted with any tertiary amine in the pr esence of the carbohydrate substrate in heterogeneous phase. The react ion is catalysed by 1-methylimidazole or by 1,4-diazabicyclo[2.2.2]oct ane, the latter being more effective. Concerning its efficacy this met hod is comparable with the classical route, using glycidyltrimethylamm oniumchloride. As in the case of most heterogeneous reactions, the acc essibility of the substrate plays an important role, thus the reactivi ty is increasing in the order cotton linters < sulphite pulp < potato starch. In the course oi the reaction the yield approaches an equilibr ium value, which is determined by the accessibility of the substrate. It was also checked, whether carboxylic groups, which may be present i n the carbohydrate, may react under the conditions applied, leading to ester linkages of the ammonium functions. This possibility was falsif ied by model investigations.