用于碳纤维的聚丙烯腈原液制备的影响因素

Influencing Factors of Polyacrylonitrile Solution Preparation for Carbon Fiber

采用丙烯腈、马来酸酐、衣康酸为聚合单体,二甲基甲酰胺为溶剂,偶氮二异丁腈为引发剂,合成聚丙烯腈(PAN)基碳纤维的原液。研究了单体的转化率、聚合物的黏度及平均分子量对聚合工艺的影响因素;同时研究了单体和引发剂浓度、聚合温度和时间对单体的转化率、黏度与黏均分子量的影响,搅拌的剪切速度、聚合物的固含量及分子量对PAN溶液黏度的影响。结果表明:单体浓度为28%,引发剂浓度达到0.7%,在60℃下反应8 h,单体的转化率和黏均分子量适中。当聚合物溶液剪切速度为3 s^-1、固含量为20%和分子量为24万时,其黏度达到最佳值45.37 Pa s,可制得适用于碳纤维生产的PAN原液。

Polyacrylonitrile(PAN)-based carbon fiber solution was synthesized by the monomer acryonitrile,maleic anhydride and itaconic acid with dimethyl formamide as solvent and azodiisobutyronitrile for initiator.The effects of monomer conversion,viscosity and average molecular weight of polymer on polymerization process were studied.At the same time,the effects of monomer and initiator concentration,polymerization temperature and time on monomer conversion,and viscosity and viscosity-average molecular weight,shear rate of agitation,solid content of polymer and molecular weight on the viscosity of PAN solution were studied.The results show that the monomer conversion and viscous average molecular weight are moderate when the monomer concentration is 28%,initiator concentration is 0.7%at 60℃for 8 hours.When the shear velocity of the polymer solution is 3 s^-1,the solid content is 20%and the molecular weight is 240 000,the viscosity reach 45.37 Pa·s of the optimal value,and the PAN solution suitable for carbon fiber production could be prepared.