摘要
采用粘度法分析了不同溶剂对壳聚糖粘度的影响 ,用光散射法测定了超声波分级的壳聚糖的相对分子质量。实验结果表明 :四种溶剂体系分别溶解壳聚糖 ,其粘度行为不同 ,溶剂的离子强度越大 ,壳聚糖的比浓粘度越小。在 0 .3mol/ L乙酸 + 0 .3mol/ L乙酸钠溶剂的条件下 ,应用 Mark-Houwink方程测得 K=0 .1 81 cm3 / g、α=0 .62 ,说明离子强度越大 ,壳聚糖分子的聚集态越大 ,α越小。为了获得准确的 K、α值和壳聚糖的相对分子质量 ,必须选择合适的溶剂体系来消除这种聚集态的影响。
The effects of different solvents on viscosity of chitosan were studied. The relative molecular mass of chitosan fractionated by ultrasonic wave was measured by the light scattering method. The experimental results show that the chitosans are dissolved in four kinds of solvent system. The larger the ionic strength of solvent, the lower the η sp / c of chitosans. The viscometric constants α and K in the Mark Houwink equation were determined for chitosan in 0.3 mol/L acetic acid and 0.3 mol/L sodium acetate solution. The values obtained are K =0.181 cm 3/g and α =0.62. The chitosan molecules shrink and become more compact due to the higher ionic strength, so a smaller value of α is found in this solvent system. In order to get reliable values of α,K and relative molecular mass of chitosan, it is necessary to choose a suitable solvent to eliminate the influence of coagulation.
出处
《化学世界》
CAS
CSCD
北大核心
2003年第8期416-418,415,共4页
Chemical World
基金
湖北省教育厅项目 ( 2 0 0 2 A0 0 0 16)
