纤维素/磷酸/多聚磷酸液晶溶液的凝固性能

Coagulation property of cellulose/phosphoric acid/polyphosphoric acid liquid crystalline solution

通过捏合机制备了纤维素在磷酸/多聚磷酸复合溶剂中的液晶溶液。讨论了纤维素在该溶剂体系中的溶解性能。利用显微镜观察法测定了该液晶溶液在丙酮、乙醇、正丙醇、乙酸乙酯、乙二醇的凝固浴中凝固层厚度随时间的变化。结果表明:在所有的凝固浴中凝固层厚度与时间的平方根成线性关系,且相关系数很高。利用菲克定律为基础的一维扩散模型对实验数据进行分析,表明所采用的凝固厚度的测试方法准确,凝固速度可作为表征凝固过程的合理参数。

A cellulose liquid crystalline solution was prepared by mixing cellulose and phosphoric acid/polyphosphoric acid mixed solute on a kneader. The dissolution properties of cellulose in the solvent system were discussed. The change of coagulation layer depth with time was measured for the liquid crystalline solution in different coagulation bath of acetone, ethanol, n -propanol, ethyl acetate and ethylene glycol by microscopic observation. The results showed that the depth of the coagulation layer was proportional to the square root of time and the correlation coefficients were extremely high. The experimental data were analyzed with an one-dimensional linear diffusion model based on Fick＇s law, which proved that the coagulation depth measurement was precise and the coagulation rate can be used as a reasonable parameter to characterize the coagulation process.