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氰乙基纤维素/二甲基甲酰胺溶液的流变性质具有假塑性流体的特征,随切变速率的增加,溶液的粘度降低。但是,在较高浓度时,溶液表现出屈服行为,屈服应力τγ的大小既与浓度有关,又与温度有关。在百τγ-C曲线上,可以看到极大值和极小值。在η-C和η-T曲线上,对应于临界浓度C_1~·和C_2~·以及临界温度T_(c1)和T_(c2),出现极大值和极小值。溶液的表观流动活化能E_η在单相(各向同性或液晶相)区域大于零,其粘度随温度的升高而降低。在两相共存区域,E_η小于零,其粘度随温度的升高而增加。
The rheological properties of cyanoethyl cellulose / dimethylformamide solution are characterized by pseudoplastic fluid, and the viscosity of the solution decreases with increasing shear rate. However, at higher concentrations, the solution exhibits yield behavior and the magnitude of yield stress, τγ, is both concentration dependent and temperature dependent. In the hundred τγ-C curve, you can see the maximum and minimum values. On the η-C and η-T curves, corresponding to the critical concentrations C_1 ~ · and C_2 ~ · and the critical temperatures T_ (c1) and T_ (c2), the maximum and minimum values appear. The apparent activation energy E_η of the solution is greater than zero in the single-phase (isotropic or liquid-crystalline) region and its viscosity decreases with increasing temperature. In the two-phase coexistence region, E_η is less than zero and its viscosity increases with increasing temperature.