Pre-oxidation of polyacrylonitrile fabric and its properties

Abstract

Pre-oxidation of polyacrylonitrile (PAN) filament is one of the important processes for the preparation of PAN based carbon fiber. Aiming at the problem that carbon fiber is easy to break in the weaving process, which affects the weaving efficiency and fabric quality, the pre-oxidation of PAN filament fabric is discussed. PAN filament bundle was pretreated with boric acid solution of 5% mass fraction in saturated cupric chloride solution, and the pretreated PAN filament bundle was woven into plain fabric, and then PAN fabric was pre-oxidized using muffle furnace. The structure and thermal properties of pre oxidized pan fabric were analyzed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetry (TG) and scanning electron microscopy (SEM) . The results showed that there were slightly more grooves on the fiber surface in the pre-oxidation fabric than in the pre-oxidation filament under the same pre-oxidation process conditions. The aromatization index of pre-oxidation fabric was higher than that of pre-oxidation filament. The weight loss temperature of fibers from pre-oxidation fabric was about 20 ℃ higher than that of pre-oxidation filament. The variation coefficient of single fiber strength from pre-oxidized PAN fabric was smaller than that from pre-oxidized PAN filament, and variation coefficient of single fiber strength of pre-oxidized PAN fabric was large than that of pre-oxidized PAN filament.

Keywords

• polyacrylonitrile fabric
• pre-oxidation
• thermal properties
• aromatization index
• single fiber strength