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机构地区:[1]北京化工大学碳纤维及复合材料研究所,北京100029
出 处:《北京化工大学学报(自然科学版)》2009年第4期71-74,共4页Journal of Beijing University of Chemical Technology(Natural Science Edition)
基 金:国家"973"计划(2006CB605302)
摘 要:通过分析PAN纤维低温热处理后的分子结构,结合PAN基碳纤维结构性能,提出了影响碳纤维模量的碳结构要素,并将其定义为"无氢芳香碳";利用核磁共振波谱(NMR)对热处理程度不同的PAN纤维中"无氢芳香碳"的相对含量进行了研究。研究结果表明:热处理时间越长,原丝纤度越低,热处理后PAN纤维结构中"无氢芳香碳"的相对含量越高,更有利于获得高模量的碳纤维。By analyzing the structure and properties of polyacrylonitrile (PAN)-based carbon fibers, it was found that the proportion of quaternary aromatic carbon atoms (i. e., those not bonded to hydrogen) in the low temperature treated structure is a key factor affecting the modulus of the final carbon fibers. The proportions of quaternary aromatic carbon atoms were determined by solid-state 13C nuclear magnetic resonance (NMR). The results showed that PAN fiber samples with smaller titer or which were treated for longer stabilization times had higher proportions of quaternary aromatic carbon atoms, and that the tensile moduli of the resulting carbon fibers were also higher.
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