Comparative characterization of solvent spun cellulose and high wet modulus viscose fibres by their long periods

The evaluation of the long periods and crystallite lengths of original and pretreated solvent spun cellulose fibres revealed that they consist of about 90% crystalline cellulose in the direction of the fibre axis. In the case of high wet modulus viscose fibres this percentage is only 50–60%. The intensity of the long period of solvent spun fibres is lower than that of the high wet modulus viscose fibres corresponding to a smaller difference between their crystalline and amorphous orientation factors. There is existing a significant correlation between this difference and the intensity of the long period.