甲壳素类液晶高分子研究——低分子量壳聚糖溶致液晶性及分子量对液晶临界浓度的影响  

STUDIES ON CHITIN-BASED LIQUID CRYSTALLINE POLYMERS——THE LYOTROPIC LIQUID CRYSTALLINITY OF LOW MOLECULAR WEIGHT CHITOSAN AND THE INFLUENCE OF MOLECULAR MASS ON CRITICAL CONCENTRATION

作　　者：董炎明[1] 黄训亭[1] 赵雅青[1] 杨柳林[1] 毛微[1] 毕丹霞[1] 赵连军 

机构地区：[1]厦门大学材料科学与工程系,厦门361005 [2]济南海得贝海洋生物制品有限公司,济南250022

出　　处：《高分子学报》2006年第1期16-20,共5页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号20374041);福建省自然科学基金(基金号E0310002);福建省重点科技项目(项目号2004I006)资助项目

摘　　要：研究了两种用酶降解法得到的低分子量壳聚糖样品(CS1和CS2)的溶致液晶性.用GPC并辅以质谱法确定了两样品的数均相对分子质量为622和2311 g/mol.在相对分子质量低至622的低分子量壳聚糖(相当于四糖)水溶液中仍发现了溶致液晶现象,并确定出相对分子质量为622和2311的低分子量壳聚糖液晶临界浓度为73%和36%(W/W%),这些结果与已报道的中、高分子量壳聚糖液晶临界浓度随分子量升高而降低的基本规律是一致的.实验结果与经典的KS理论预测值不符,因为低分子量壳聚糖的相对分子质量超过了KS理论对高分子临界浓度的预测范围.The lyotropic liquid crystallinity of two low molecular weight chitosan samples prepared by enzymic decomposition was investigated. The number averge molecular masses of those two samples CS1 and CS2 were 622 and 2311 g/mol, measured by means of GPC and MS. The lyotropic liquid crystalline behavior was found for these samples even when the molecular mass was as low as 622 g/mol （ - tetramer）. The critical concentration of CS1 and CS2 to form liquid crystalline phase was determined to be 73 wt% and 36 wt% respectively.The results agree with the principle rule deduced from chitosans with high and medium molecular mass, which states that the critical concentration increases with the decrease of molecular mass. However the results were not accordant with those predictd by the traditional Khokhlov-Semenov（KS） theory, because the molecular mass of the samples is out of the region in which KS theory can be used.

关 键 词：低分子量壳聚糖 溶致液晶 液晶临界浓度 酶降解法 

分 类 号：O753.2[理学—晶体学]