Sorption Properties of Polyacrylonitrile Fibres

As-spun undrawn PAN fibre wet-spun from solutions of the polymer in DMF, DMA, and DMSO are porous with a developed specific surface (up to 80 m2/g for nitrogen), while fibres spun from aqueous solutions of sodium thiocyanate or zinc chloride are nonporous with a specific surface of under 1 m2/g. The finished PAN fibres spun from solutions in different solvents have a closely packed structure, equivalent to highly crystalline, according to the data from sorption of inert gases and water vapors, and according to the results on the kinetics of sorption of vapors of liquids with different molecule sizes, they can be considered ultramicroporous.