稀溶液黏度法研究醋酸纤维素/聚乙烯吡咯烷酮共混物的相容性

Miscibility Studies on Blends of Cellulose Acetate and Polyvinylpyrrolidone by Dilute Solution Viscometry

以冰醋酸为共溶剂,利用乌氏黏度计在25℃研究了醋酸纤维素(CA)、聚乙烯吡咯烷酮(PVP)以及不同组成的CA/PVP共混物(CA的质量分数分别为0.1、0.2、0.3、0.4、0.5、0.6、0.7、0.8、0.9)的粘性行为。基于稀溶液黏度法确定的4种相容性判据(Δb,Δb’、Δ[η]m和α)探讨CA/PVP共混体系的相容性。实验结果表明,当醋酸纤维素在CA/PVP共混体系中的质量分数低于0.12或者在0.8～0.91范围内时,CA与PVP是相容的,其余的组成体系都是不相容的。因此,CA/PVP共混体系是部分相容体系。

The viscosity behavior of cellulose acetate,polyvinylpyrrolidone and their blends of different compositions（CA mass fraction in the blend is 0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8 and 0.9,respectively） has been studied using acetic acid as the common solvent by the Ubbelohde viscometer at 25 ℃.The miscibility of this polymer system was investigated on the basis of the sign of the criteria Δb,Δb′,Δ[η]m and α determined by viscosity.The results indicate that CA/PVP blend is miscible when the CA content is less than 0.12% and between 0.8 and 0.91 in the blend at 25 ℃.CA/PVP blend is immiscible at the rest composition.Therefore,CA/PVP system is partial miscible in acetic acid.