Self-Bonding Boards From Plantain Fiber Bundles After Enzymatic Treatment: Adhesion Improvement of Lignocellulosic Products by Enzymatic Pre-Treatment

Self-bonding boards were manufactured with treated fibers at different concentrations of a laccase enzyme. This enzyme induced the generation of phenoxy radicals in the fiber lignin which can generate covalent bonds and cross-linked by radical-radical coupling. The effect of laccase concentration on the properties of obtained fiberboards was evaluated. The formation of free radicals and changes in the lignin macromolecule was measured using scavenging activity test, infrared spectroscopy, electron paramagnetic resonance and scanning electron microscopy. Thermal and mechanical properties of the resulting fiberboards were determined by differential scanning calorimetry, thermo gravimetric analysis and flexion tests. Increased thermal stability, modulus of elasticity and modulus of rupture and also, a reduction in thickness swelling and water absorption, were observed at higher concentrations of laccase. These results are ascribed to the effect of the free radicals that were generated during the enzymatic treatment.