高性能有机纤维耐热性能与结构演变研究  

Study on heat resistance and structural evolution of high-performance organic fibers

作　　者：周映 高鸿[2] 张梦颖[1] 牛鸿庆[1] 武德珍[1] 汪晓东[1] ZHOU Ying;GAO Hong;ZHANG Mengying;NIU Hongqing;WU Dezhen;WANG Xiaodong(State Key Laboratory of Chemical Resource Engineering,Beijing University of Chemical Technology,Beijing 100029;China Academy of Space Technology,Beijing 100094)

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室,北京100029 [2]中国空间技术研究院,北京100094

出　　处：《合成纤维工业》2019年第4期6-14,共9页China Synthetic Fiber Industry

基　　金：国家重点研究计划(017YFB0307602);国家自然科学基金项目(5179500011)

摘　　要：高强度耐高温有机纤维兼具高强高模和良好的热稳定性,可在200~300℃长期使用。采用傅里叶红外光谱仪、热重分析仪、动态热机械分析仪、广角X射线衍射仪、扫描电子显微镜研究了聚对苯二甲酰对苯二胺(PPTA)、芳纶Ⅲ、聚对苯撑并苯双噁唑(PBO)和聚酰亚胺(PI)4种高强度耐高温有机纤维在250~450℃下热处理一定时间后的尺寸稳定性和力学性能变化,以及纤维的化学、凝聚态结构和形貌演变,并结合电子云密度和键级分析其耐热机理。结果表明:化学结构和凝聚态结构是影响纤维耐热性能的关键因素,PPTA纤维和芳纶Ⅲ分别在400℃和450℃热处理10h后化学结构会发生明显降解,PBO和PI纤维在同样条件下其化学结构不会产生明显变化;纤维的缺陷结构及结晶度的变化也对其耐热性能产生显著的影响,4种纤维在通过热处理后,芳纶Ⅲ的表面缺陷最为明显,PI纤维表面缺陷不明显;PI亚酰胺环的电子云密度最大,其抵抗外部能量攻击的能力高,热处理温度小于400℃时,PI纤维的强度保持率最高。High-strength and high-temperature resistant organic fiber can be used at 200-300°C for a long time due to its high strength,high modulus and good thermal stability.The change of the dimensional stability and mechanical properties of four kinds of high-strength and high-temperature resistant organic fibers,including poly-p-phenylene terephthalamide(PPTA)fiber,aramid fiberⅢ,poly-p-phenylenebenzobisoxazole(PBO)fiber and polyimide(PI)fiber,were studied after heat treating for a certain period of time at 250-450℃by Fourier transform infrared spectrometry,thermogravimetric analysis,dynamic thermomechanical analysis,wide angle X-ray diffraction and scanning electron microscopy,as was the chemical,condensed structure and morphology evolution of the fibers.The thermal resistance mechanism of the fibers was analyzed by electron cloud density and bond level.The results showed that the chemical structure and condensed structure are the key factors affecting the heat resistance of fibers;the chemical structure of PPTA fibers and aramid fiber III degraded obviously after heat treatment at 400℃and 450℃for 10 h respectively when the chemical structure of PBO and PI fibers did not change significantly under the same conditions;the change of defect structure and crystallinity of the fibers also had a significant effect on their heat resistance,and the surface defects of aramid fiber III were the most obvious while the surface defects of PI fibers were not obvious after heat treatment;and the imide ring of PI was the highest in electron cloud density and had a high resistance to external energy attack,and the strength retention rate of PI fiber was the highest when the heat treatment temperature was lower than 400℃.

关 键 词：聚对苯二甲酰对苯二胺 芳纶Ⅲ 聚对苯撑并苯双噁唑 聚酰亚胺 耐热性能 

分 类 号：TQ342.72[化学工程—化纤工业] TQ342.73