壳聚糖的表面性能及分子量与脱乙酰度的影响

应用红外光谱法对四种壳聚糖样品进行了结构表征,同时估算了其脱乙酰度,并用粘度法测定了分子量。根据Washburn的浸渍理论和van Oss-Chaudhury-Good的组合理论,应用柱状灯芯技术,对壳聚糖的表面性能进行了测试。研究发现,壳聚糖的分子量和脱乙酰度都影响其表面性能。当脱乙酰度相同时,分子量与表面能γS及表面能分量γSLW、酸碱比值γS+/γS-成正比,而与其酸性力γS+和碱性力γS-以及极性率γAB/γs成反比;而分子量相近时,表面性能可能主要受脱乙酰度的影响。随着脱乙酰度的增加,壳聚糖的表面能γS及其分量γSLW、酸碱比值γS+/γS-都增大。实验所测得的壳聚糖的表面能数据得到文献的支持。

Surface Properties of Chitosan and the Influence of Degree of Deacetylation and Degree of Polymerization

Applying FT-IR spectroscopy for characterizing the structure and intrinsic viscosity measurement for measuring the molecular weight for four chitosans initially,the surface properties of these four chitosans were further studied by considering the influence of both the degrees of deacetylation,DD,and polymerization,DP,and using the column wicking technique in relation to the theories of Washburn penetration and van Oss-Chaudhury-Good’s combing rules.Results showed that the degrees of deacetylation and polymerization are two important factors to influence the surface free energy and related components for chitosans.For example,the same of the DD,the influence from DP is that the higher the DP,the greater is the surface free energy,the Lifshitz-van der Waals component and the Lewis acid/base ratio,while the Lewis acid,Lewis base and polarity on the contrary.For similar DP,the DD is a principle dominator to influence the surface properties.It was found that this experiment resulted values were supported by literatures.