Modification of Lignocellulosic Materials by Laccase, 2003 Fall Technical Conference

Altering the surface properties of pulp can enhance binding, increase paper strength, and decrease the cost of fiber. In this study, we modified lignocellulosic materials (bark and pulp) with laccase and selected substrates to change the nature of the pulp surface. Modified pulps were evaluated by the amount of methylene blue (a cationic dye) that would bind to the pulp and the acid–base and dispersive results of inverse gas chromatography (IGC) analysis. Combinations of laccase and substrates that altered various surface properties of the pulp were determined. Methylene blue binding increased for many of the substrates but did not correlate with the IGC-determined acid– base characteristics of the pulp, indicating involvement beyond cation binding. Substrates that altered the surface characteristics of loblolly pulp were used on a thermomechanical spruce pulp. The treated spruce pulps were analyzed for handsheet strength and binding characteristics. Modest strength improvements were observed in some of the treatments. Laccase treatments to alter pine bark were also explored.