纺丝溶液的挤出对聚丙烯腈初生纤维表面形态的影响

采用旋转流变仪并结合Tanner黏弹性流体挤出胀大方程研究了剪切对聚丙烯腈/二甲基亚砜(PAN/DMSO)溶液挤出胀大的影响，用原子力显微镜(AFM)研究了挤出速度对PAN初生纤维表面粗糙度的影响规律。结果表明：随着挤出速度的增大，体系的挤出胀大比逐渐增大，当挤出速度大于90m/h时，挤出胀大比的变化出现拐点，增大的趋势变缓；聚合物大分子链的回复是初生纤维表面形貌形成的主要原因，湿法纺丝过程中，挤出速度低于90m/h时初生纤维表面粗糙度随着挤出速度增加而减少，在较高挤出速度时，随着挤出速度增加而增加；干湿法纺丝初生纤维的表面粗糙度明显低于湿法纺丝，并且随挤出速度的增加而增大。

Effect of spinning solution extrusion on the surface morphology of polyacrylonitrile as-spun fibers

The effect of shearing on the extrusion die swelling of solutions of polyacrylonitrile in dimethylsulfoxide(PAN/DMSO) has been modeled by the Tanner equation using rheological data,and the effect of the extrusion speed on the surface roughness of PAN as-spun fibers was investigated by atomic force microscopy.The results showed that the extrusion die swelling of PAN/DMSO solutions was more obvious at higher extrusion speeds.The surface roughness of the PAN as-spun fibers was dependent on the recovery of PAN macromolecules after the PAN/DMSO solution was extruded from the spinneret.For wet spinning,the surface roughness of the as-spun fiber decreased with increasing extrusion speed,until the extrusion speed reached 90 m/h,after which rougher surfaces were observed at higher extrusion speeds.For a dry-jet wet spinning process,the surface roughness of PAN as-spun fibers was significantly lower than for the wet spinning process,and increased slightly with increasing extrusion speed.