The Research On The Pores' Structure Of Polyacrylonitrile Fiber

Carbon fiber based on Polyacrylonitrile(PAN) is a brittle material. Its mechanical property is restricted by the pore defect and crystal structure. Recently, during the formation and preoxidation of the PAN fiber, a pore with nanometer grade was highly noticed.PAN fiber was prepared, using wet spinning method, and preoxidated under different temperature gradient. The formation of crystal structure and the development rule of the micropore structure in PAN precursor were studied by wide angle X-ray diffraction and small angle X-ray diffraction. The formation rule of pore defect during coagulation, especial the influence of temperature, concentration and tension to the crystal and micropore structure of PAN primary fiber, were explored by scanning electronic microscopic(SEM). By using wide angle X-ray diffraction, small angle X-ray diffraction, DSC, TG and optical microscope, the formation and development rule of micropore defect and morphosis...