Variation in the response of three different Pinus radiata kraft pulps to xylanase treatments.

摘要

Two xylanase preparations (Pulpzyme HC and Xylanase E) were assessed for their ability to enhance the refining properties of three different Pinus radiata kraft pulps. Both preparations selectively solubilized a significant proportion of the available xylan; however, xylanase E proved to be more aggressive, regardless of the pulp type. The selective removal of pulp xylan improved pulp beatability by increasing the apparent densities of the resultant handsheets over their corresponding controls. There were, however, variations in the response of the different pulp types, with an unbleached kappa 70 pulp showing the greatest improvement in sheet densification, as compared to an isothermal-cooked (kappa 33) and a fully bleached pulp. In general, xylanase treatments improved tear strength at a given density without significant loss in tensile strength and intrinsic fibre strength. These results suggest that xylanase treatments may be a means of enhancing the collapsibility/flexibility of certain kraft fibres while maintaining intrinsic strength.