PAN基碳纤维原丝用纺丝溶液的流变性质

Rheological behavior of polyacrylonitrile spinning solution for making carbon fiber

为制备适于干 -喷湿纺用PAN(polyacrylonitrile)纺丝溶液 ,选用了较高粘均相对分子质量的PAN ,通过测定纺丝溶液的回转粘度 ,对其流变性能进行了较为详尽的研究。研究结果表明 :粘均相对分子质量为近 2 0万的PAN溶液为切力变稀型流体 ,具非牛顿性。在40～ 80℃的温度范围内 ,浓度为 18%～ 2 0 %的纺丝溶液的临界切变速率为 10 0 9～ 10 1 7。提高纺丝溶液的浓度可使溶液的粘流活化能 (Eη)及结构粘度指数 (Δη)增大、非牛顿指数 (n)减小 ;

In order to obtain PAN(polyacrylonitrile) spinning solution for dry-jet wet spinning, PAN with higher relative molecular mass was chosen to produce PAN spinning solution, which rheological behavior was investigated in detail with the help of rotating viscosity. The flow curves show that the spinning solution prepared from higher relative molecular mass belongs to shear thinning fluids and is of non-Newtonian behavior. When the temperature is between 40 and 80 degrees C, critical shear rate for solution with concertration from 18% to 20% changes from 10 0 9 to 10 1 7. The increase of concertration of spinning solution will raise the viscous activation energy(E η) as well as structural viscosity index(Δη) while decrease the non-Newtonian index(n). Whereas with the decreasing of temperature, Δη will become less along with n rising. All of these results can provide useful instructions for producing precursor for PAN-based CF.