ENHANCED BLEACHING AND SOFTENING OF JUTE PRETREATED WITH POLYSACCHARIDE DEGRADING ENZYMES

Treating jute fibers with enzymes effects an increase in pore volume ( 46.2%), which leads to an increased capacity to retain peroxide (25.5% ) and a larger surface area of lignin accessible to the oxidant (appro ximately 30%). Improved bleaching is therefore achieved. Enzyme treatm ent increases transverse swelling (14%) and reduces bulk torsional rig idity (12.5%), making the fibers more flexible and therefore softer. T he removal of cementing materials such as hemicellulose and lignin by bleaching is enhanced by enzyme pretreatment, resulting in better fila mentation and fineness. Scanning electron micrographs confirm this. Ex periments with purified enzyme preparations have shown that xylanase p retreatment predominates in facilitating bleaching, and cellulase in t he swelling or softening. An appropriate combination of the two is req uired to obtain optimal effects.