摘要
为优化聚酰亚胺(polyimide,PI)基碳纤维的结构和性能,通过改变二胺单体配比,采用湿法纺丝技术制备出不同化学组成的BPDA/PDA/ODA体系PI纤维,随后经1 500℃连续高温处理后得到PI基碳纤维。采用傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)、热重-红外联用(thermogravimetric-infrared radiation,TG-IR)、元素分析仪(elemental analyzer,EA)、Raman光谱、广角X衍射(wide-angle X-ray diffraction,WAXD)和扫描电子显微镜(scanning electron microscope,SEM)等方法探究PI纤维化学组成对其碳纤维结构和性能影响。结果表明,所制备的PI基碳纤维表面光滑、结构致密,碳收率和含碳量分别高于45%和90%,具有良好的导电性能。随着二胺单体PDA/ODA摩尔配比的增大,所得PI基碳纤维微晶结构更加完善,碳收率、含碳量、石墨化程度和导电性能提高。并提出了碳化过程中纤维化学结构变化的假想,PI纤维侧向有序度和平面规整度越高,PI基碳纤维微晶结构越完善。
To improve the structures and properties of the polyimide(PI)-based carbon fibers,a series of BPDA/PDA/ODA PI fibers with different chemical compositions were prepared through wet-spinning method,following by carbonization at 1 500℃to obtain the PI-based carbon fibers.The effects of PIs’structure on the structures and properties of their carbon fibers were investigated by Fourier transform infrared spectroscopy(FTIR),thermogravimetric-infrared radiation(TG-IR),elemental analyzer(EA),Raman spectra,wide-angle X-ray diffraction(WAXD)and scanning electron microscope(SEM)analyses.The results indicate that the PI-based carbon fibers possessed smooth surface,compact inner structure,with the carbon yield higher than 45%,the carbon content higher than 90%and the excellent electrical properties.The crystalline structure,the carbon yield and content,the graphitization degree as well as the electrical properties of the PI-based carbon fibers were improved with the increased PDA/ODA molar ratios.Moreover,the chemical structural variation hypothese of the fibers during carbonization was proposed.The high degree of the lateral packing order and plane regularity of the PI fibers benefited the formation of the perfect crystalline structure of the PI-based carbon fibers.
作者
张梦颖
牛鸿庆
武德珍
ZHANG Mengying;NIU Hongqing;WU Dezhen(College of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China)
出处
《中国科技论文》
CAS
北大核心
2018年第4期450-455,共6页
China Sciencepaper
基金
国家重点研发计划重点专项(2017YFB307600)
高等学校博士学科点专项科研基金资助项目(20130010130001)
国家自然科学基金资助项目(51373008)
关键词
材料
纤维
聚酰亚胺
碳化
化学组成
material
fiber
polyimide
carbonization
chemical composition
