PAN纤维预氧化过程的结构变化及热行为  

Structural transformation and thermal behavior of PAN fibers during the preoxidation

作　　者：杨玉蓉[1] 闫国民[1] 刘立[1] 张秀平[1] 牟艳男[1] 华中[2] 

机构地区：[1]黑河学院物理系,黑河164300 [2]吉林师范大学功能材料物理与化学教育部重点实验室,四平136000

出　　处：《化工新型材料》2014年第8期167-169,共3页New Chemical Materials

基　　金：黑龙江省自然科学基金青年项目(QC2013C005)

摘　　要：采用X射线衍射（XRD）、透射电子显微镜（TEM）和差示扫描量热分析（DSC）研究了PAN纤维在预氧化过程的结构和热性能变化。结果表明：随着预氧化温度的升高，纤维的微晶尺寸增大，到220～230℃时达到最大，此后逐渐减小，原准晶结构逐渐被破坏。纤维的芳构化指数随预氧化温度的升高不断增大，PAN链状分子在逐渐演变成梯形环状分子结构，230℃和275℃是PAN原丝热稳定化的转折点。随着预氧化温度的升高，洋葱球非晶组织发生了结构演变。非晶化转变是从晶区边界开始，由外部向芯部逐步进行。纤维的环化度随着预氧化温度的升高表现为增大。在较低温度增加较快，随后增加变缓。230℃后，环化反应加剧，环化度迅速提高。The structure and thermal properties changes of PAN fibers in the preoxidation procession were studied by XRD,TEM and DSC. The results showed that the crystallite size of fibers increased with temperature, reached the maxi-mum from 220℃ to 230℃,then decreased gradually. Aromatization exponent increased with temperature continually. PAN chain molecules evolved into trapezoidal cyclic molecular structure,230 and 275℃ was the turning point of PAN precursor in the thermal stabilization. With the increase of preoxidation temperature,the onion-like amorphous organization structure was changed. Amorphization was started from the crystal boundary, changed from exterior to the core step by step. Cyclization index increased with temperature, which increased rapidly at low temperature, then increased slowly. After 230℃, cyclization reaction was intensified,cyclization index improved rapidly.

关 键 词：PAN纤维 预氧化 微晶尺寸 芳构化指数 环化度 

分 类 号：TQ342.3[化学工程—化纤工业]