Functional hybrid fibers of cellulose/microcrystalline chitosan. I. Manufacture of viscose/microcrystalline chitosan fibers

Blends of microcrystalline chitosan (MCCh) with cellulose xhanthate alkalin e solutions were prepared to investigate the effects of aqueous MCCh gel co ncentration and additives on the spinnability of hybrid cellulose/chitosan fibers and their properties. The properties of the spinning solution were m ainly dependent on the concentration of MCCh in the aqueous gel-like disper sion and the amount mixed into the cellulose xhanthate solution. Sodium alg inate chemically close to cellulose and chitosan was used as an additive to improve the miscibility of chitosan due to the ionic bonds formed with chi tosan 2-amino groups. Using an optimized ratio of 2 : 1 of MCCh to the sodi um alginate, a maximum of 6% of MCCh calculated from alpha-cellulose conten t could be introduced into the sodium xhanthate solution containing origina lly 9% of alpha-cellulose. The yield of MCCh in the resulting fibers was de pendent on the molecular mass, and varied between 73- 82%. The strength, el ongation, and color of the resulting hybrid fibers were only slightly chang ed and the WRV remarkably increased compared to standard fibers. (C) 2000 J ohn Wiley & Sons, Inc.