为了比较聚丙烯腈原丝制备过程中不同加氨方式对于初生纤维结构的影响,采用聚合初期加氨、聚合后脱单前加氨、凝固浴加氨这3种加氨工艺,聚合物经过凝固过程得到初生纤维。通过对初生纤维进行显微镜、X射线衍射以及傅里叶红外的表征,来分析纤维截面形貌以及晶态结构的变化。结果表明:在使用相同当量的氨的情况下,聚合初期加氨更容易附着于纤维上,有助于双扩散的进行,有效地阻止了皮芯结构的产生,纤维径向结构更加均匀,结晶度更高。

In order to compare the influence of different ways of adding ammonia on the fiber structure in the preparation process of polyacrylonitrile(PAN) nascent fiber,three ammonia adding processes,namely,adding ammonia at the initial stage of polymerization,adding ammonia before stripping and adding ammonia in coagulation bath,were adopted to obtain the nascent fiber through the coagulation process.By means of the microscopy,XRD and FT-IR the fiber was characterized,the section morphology and crystal structure of the fiber were analyzed.The results shown that when the same equivalent ammonia was used,the addition of ammonia in the initial stage of polymerization was easier to adhere to the fiber,which was conducive to the process of double diffusion and effectively prevented the generation of skin and core structure.The radial structure of the fiber was more uniform and the crystallinity was higher.