【作者】 冯春祥； 范小林； 宋永才；

【Author】 Feng Chunxiang Fan Xiaolin Song Yongcai (National University of Defense Technology, Changsha, Hunan, 410073)

【机构】 国防科学技术大学材料科学工程应用化学系；

【摘要】 文中采用TG、气相色谱、红外光谱、²⁹Si MAS NMR、元素分析等对聚碳硅烷纤维的氨化反应过程及机理进行了详细的研究。研究结果表明:氨化反应在400℃以下即可发生,随着反应温度的升高,氨化反应的速度加快,反应机理也相应地有所变化。当温度升到在700℃以上时,则不利于氨化反应的深入进行。更多还原

【Abstract】 N-H bond was introduced into PCS through the nucleophilic displacement of Si-H, Si-CH3 with NH3. Using TG, IR, 29Si MAS NMR and GC, the mechanism of ammoniation process of PCS was studied. It was found that the ammoniation, or the nucleophilic displacement between Si-H, Si-CH3 and NH3, can only start above 36℃. The reaction between Si-H and NH3 is preferred below 600℃, while between 600-700℃, that between Si-CH3 and NH3 is preferred. At even higher temperature, the ammoniation will be hindered. Longer reaction time, higher NH3 concentration and temperature are favored for increasing the nitrogen content.更多还原