摘要
通过使用XPS和XRD等表征手段研究了经低温碳化后PAN纤维中氮结合态的高温演变规律,推测了其反应机理,探讨了由氮结合态的演变所引起的纤维结构变化。结果表明:经低温碳化后PAN纤维中的氮主要以吡啶氮、叔胺氮和氨基/亚氨基3种结合态存在,当热处理温度在700℃以下时,纤维中吡啶氮含量最多;随着温度的升高,氨基/亚氨基和吡啶氮含量逐渐减少,而叔胺氮含量先呈增加趋势,温度升高到1000℃以后时,叔胺氮含量迅速下降;1300℃以后,纤维中的叔胺氮含量最多;PAN纤维中的氮以叔胺氮形式存在更有利于平面六元碳网的逐步完善。
The high-temperature evolution of the combination state of N in PAN fibers through carbonization in a low temperature was studied,the reaction mechanism was speculated,and the fibers structure changes caused by the evolution of the combination state of N was discussed.The results indicated that N in PAN fibers through carbonization in a low temperature existed in three combination states as the pyridine nitrogen,amino(or imino) and graphite-like nitrogen.The pyridine nitrogen content was the most when the heat treatment temperature was below 700℃.With the increase of the heat-treatment temperature,amino(or imino) and the pyridine nitrogen content decreased,while the tertiary nitrogen content increased at first and then decreased quickly when the temperature was higher than 1000℃.When the heat-treatment temperature was above 1300℃,the tertiary nitrogen content was the most.N in PAN fibers existed in the tertiary nitrogen was better for the improvement of the plane six carbon net.
出处
《化工新型材料》
CAS
CSCD
北大核心
2012年第1期84-87,共4页
New Chemical Materials
基金
国家科技部973项目(2011CB605602)