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制备了不同脱乙酰度和分子量在１－３ ～１５－１ ×１０５ 范围内的壳聚糖样品，并用傅里叶变换红外光谱法（ＦＴＩＲ）和粘度法进行了表征．借助偏光显微镜研究了不同壳聚糖样品在二氯乙酸中的液晶相转变和液晶状态．实验结果表明，分子量在１０５ ～１０６ 范围内的增大使壳聚糖形成液晶相的临界浓度（ Ｃ＊ ） 略有降低；脱乙酰度在７０ ～９０ ％ 范围内，对Ｃ＊ 的影响基本可以忽略．临界浓度的实验值与根据ＫｈｏｋｈｌｏｖＳｅｍｅｎｏｖＯｄｉｊｋ 理论预示的值比较一致，说明蠕虫链模型可以很好地描述壳聚糖分子链在二氯乙酸中的溶致液晶行为．
Chitosan samples with different degrees of deacetylation and molecular weights in the range of 1-3 ~ 15-1 × 105 were prepared and characterized by Fourier transform infrared spectroscopy (FTIR) and viscometry. The liquid crystal phase transitions and liquid crystal states of different chitosan samples in dichloroacetic acid were studied by polarization microscope. The experimental results show that the increase of the molecular weight in the range of 105-106 slightly decreases the critical concentration (C *) of chitosan to form the liquid crystal phase. The degree of deacetylation is in the range of 70-90%, and the effect on C * can be neglected . The experimental results of the critical concentration are in agreement with the values predicted by the KhokhlovSemenovOdijk theory, indicating that the worm-chain model can describe the lyotropic liquid crystal behavior of chitosan molecular chains in dichloroacetic acid.