标题：Influence of pre-cyclic treatment of PAN on properties of pre-oxidized PAN fibers
作者机构：[Yang, Yangong ] College of Material, Shandong University of Technology, Zibo 255049, China
来源：Gaofenzi Cailiao Kexue Yu Gongcheng/Polymeric Materials Science and Engineering
摘要：This thesis researched the influence of pre-oxidized polyacrylonitrile (PAN) fiber on mechanical property and flame retardancy using cyclization pretreatment method. The results show that better mechanical property and flame retardancy of pre-oxidized polyacrylonitrile fiber can be obtained by hydroxylamine pretreatment first and hydrazine hydrates pretreatment later, when the pre-oxidation temperature is 260 °C, the 36. 5% limiting oxygen index pre-oxidized poly acrylonitrile flame retardant fibers can be obtained. Taking an ulterior step of scanning electron microscope observe, by way of surface treatment and pre-oxidation the fiber's apparent-structure has been minor alteration; fiber's crackle has been clear reduced after surface treatment and restitute a little bit level after pre-oxidation. Infrared spectrum shows that although a few pyridyl structures have been produced after surface treatment, a lot of pyridyl structures produced after pre-oxidation. X-ray diffraction shows that by way of surface treatment and pre-oxidation the fiber's structure doesn't have so much change, in some level it's still be a quasicrystals ordered structures and composited by high lateral order and non-crystalline region.