【摘 要】
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Carbon fibers(CFs)were prepared using polyacrylonitrile(PAN)fibers pre-irradiated with γray irradiation in air pri-or to heat-treating and then by continuous stabilization and carbonization.And the st
【机 构】
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State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,College of Materials
论文部分内容阅读
Carbon fibers(CFs)were prepared using polyacrylonitrile(PAN)fibers pre-irradiated with γray irradiation in air pri-or to heat-treating and then by continuous stabilization and carbonization.And the structure changes of fibers during heat-treating and mechanical properties of resultant CFs were investigated using dynamic mechanical analysis,wide-angle X-ray diffraction,small-an-gle X-ray scattering and universal testing machine etc.It is found that not only the stabilization time was shortened with the increase of irradiation doses,but also the preferred orientation of carbon layers in CFs was increased with irradiation dose increasing to 100 kGy and decreased with further irradiating.Resultantly,the tensile strength and Youngs modulus of CFs were increased by 13.2%and 2.6%at an optimal dose of 100 kGy,respectively,in which skin-core structure in CFs was relieved according to SEM images.So,it is believed that irradiation technology assisted stabilization has a significant potential in CF industry.
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