羧甲基壳聚糖及其纤维的制备及表征

Preparation and characterization of carboxymethylchitosan and its fibers

用氯乙酸改性处理壳聚糖(CS)制备羧甲基壳聚糖(CMCS),采用湿法纺丝法制备CMCS纤维,考察了纺丝原液浓度、醋酸水溶液体积分数、凝固时间对CMCS纤维力学性能的影响;通过傅里叶变换红外光谱、X射线衍射以及热失重分析对CS,CMCS及其纤维进行表征。结果表明:CMCS发生了羧甲基取代,同时CMCS结晶度降低;CMCS纤维结构中含有结合水,热分解温度为270℃;纺丝原液CMCS的质量分数为50%,醋酸水溶液的体积分数为2%、凝固时间为12 min时,CMCS纤维的断裂强度达0.644 cN/dtex。

Carboxymethylchitosan （CMCS） was prepared from chitosan （CS） modified with chloroacetic acid and was spun into CMCS fiber by wet spinning process. The effects of spinning dope concentration, acetic acid volume fraction and coagulation time on the mechanical properties of CMCS fiber were investigated. CS, CMCS and their fibers were characterized by Fourier transform infrared spectrometry, X-ray diffraction and thermogravimetric analysis. The results showed that the crystaUinity of CMCS decreased when the substitution reaction of carboxymethyl group occurred in CMCS; the bound water existed in the structure of CMCS fiber and the thermal degradation temperature was 270℃ ; and CMCS fiber acquired the breaking strength of 0.644 eN/dtex under the conditions of 50% CMCS by mass fraction, 2% acetic acid solution by volume fraction, coagulation time 12 min.