湿法纺丝条件对临界凝固时间的影响

The effect of wet spinning condition on critical coagulation time

以聚丙烯腈-二甲基亚砜-水体系为研究对象,通过建立数学模型,对聚丙烯腈湿法纺丝凝固的初期阶段进行研究。借助MATLAB软件,采用有限元法对数学模型进行求解。利用数学模型考察纺丝条件对纺丝液临界凝固时间的影响。结果表明:(1)凝固浴浓度在一定程度上决定凝固进程;纺丝液临界凝固时间随凝固浴浓度升高而增加,且增加的趋势是越来越快,当浓度大于60%尤为明显;(2)纺丝液临界凝固时间随纺丝液中水含量的增加而减小,使纺丝液凝固时发生瞬时相分离的趋势增大;(3)随着喷丝孔直径的增加,纺丝液临界凝固时间会延长。

Based on the spinning system of PAN/DMSO/H2O,the critical coagulation time has been estimated in certain wet spinning condition by the modeling method.We obtained the numerical solution of difusion equation with the help of finite element method.The results showed bath concentration played important role in the coagulation process during wet spinning.The critical precipitation time increased with bath concentration increasing and the increase of critical precipitation time became faster with bath concentration increased,especially above 60%.The critical precipitation time decreased with H2O concentration in spinning solution increased and the chance of instantaneous demixing became larger.The critical precipitation time became smaller with the radius of small holes of a spinneret decreased.