两亲性羧甲基壳聚糖衍生物的表面活性研究

将羧甲基壳聚糖与烷基缩水甘油醚在碱性条件下反应,合成了一系列新型的两亲性化合物(2-羟基-3-烷氧基)丙基-羧甲基壳聚糖,对其表面性质的研究结果表明,对同一衍生物,在所研究范围内,取代度越高,降低表面张力的能力及效率越高;对同一取代度的不同衍生物,疏水链越长,降低表面张力的能力越强;对链较短和取代度较大的衍生物,如(2-羟基-3-丁氧基)丙基羧甲基壳聚糖(HBP-CMCHS),在外加电解质存在时溶液的表面张力曲线出现2个转折点,表明可能有分子内胶束形成;而对链较长的衍生物,如(2-羟基-3-十二烷氧基)丙基羧甲基壳聚糖(HDP-CMCHS),则无明显的临界胶束浓度,有外加电解质时表面张力曲线也未出现2个转折点.

Surface Activity of Amphiphilic Derivatives of Carboxymethylchitosan

A new type of amphiphilic derivatives of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with alkyl glycidol ether. The surface properties were studied by means of surface tension. It was found that for the same chitosan derivative, within some substitution degree(SD), the efficiency and effectiveness of the decreasing of surface tension increased with the increase of SD. For the similar SD of the same series of carboxymethylchitosan derivatives, the longer the amphiphilic group chain length, the more the surface activity. When the SD of the carboxymethylchitosan derivatives was high and the amphiphilic group chain length was not very long, two transitions points appeared in the surface tension vs. concentration curve, which means the possibilities of the formation of intramolecular micelle. These phenomena did not appear for the derivatives with less SD and long amphiphilic group chain length.