Premium
Visualization of microfibrillar elements in cross‐section of polyacrylonitrile fiber along the fiber spinning line
Author(s) -
Gao Quan,
Jing Min,
Chen Meiling,
Zhao Shengyao,
Wang Wenli,
Qin Jianjie,
Wang Chengguo
Publication year - 2019
Publication title -
microscopy research and technique
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 118
eISSN - 1097-0029
pISSN - 1059-910X
DOI - 10.1002/jemt.23372
Subject(s) - polyacrylonitrile , materials science , composite material , fiber , ultimate tensile strength , microfibril , scanning electron microscope , transmission electron microscopy , spinning , electron microscope , fibril , transverse plane , high resolution transmission electron microscopy , polymer , chemistry , nanotechnology , optics , anatomy , cellulose , biochemistry , physics , organic chemistry , medicine
The microfibrils served as the structural elements in polyacrylonitrile (PAN) fiber, which played an important role in the quality of the PAN precursor fibers. Their morphologies were examined by the scanning electron microscopy (SEM), atomic force microscopy (AFM) and high‐resolution transmission electron microscope (HRTEM). The microfibrils existed in all of PAN fibers and arranged evenly in the cross‐sections. Furthermore, the pores existed between the microfibrils. The unoriented microfibrillar network was already formed in nascent fiber during coagulated process. Although the microfibrillar network was elongated and the microfibrils oriented along the fiber longitudinal direction during the spinning process, the interconnected microfibrillar network was still existed in the fiber transverse section. Furthermore, the transverse connection of the microfibrils was reinforced and the small microfibrils were tended to aggregate into the large fibrils. For mechanical performance of PAN fibers, their tensile strength increased to 708 MPa and the elongation at break decreased to 15.5%. PAN fibers exhibited ductile rupture during the mechanical test and the microfibrils served as reinforcing elements.