Application of Mediators in Enzymatical Activation of Fiberself Cohesions for the Production of Enzyme-Bonded, Binder-Free Derived Timber Products

摘要

This study investigated the substitution of petrochemical components in binders for derived timber products (especially medium density fiberboard [MDF]) by using a system of enzyme and mediators, which operate as redox molecules between enzymes and lignin. The enzymes were produced by lignin-de-composing fungis (e.g., Trametes versicolor) in fer-menters. After the addition of mediators, the enzyme-mediator-solution was mixed with wood fibers for pressing MDF. The goal of the first step was to increase the surficial structure of the wood fibers (Pinua syl-vestris) through enzymatic activation of their own cohesions. Results of the incubation of the wood fibers with enzyme-mediator-mixture showed a significant increase of the radical-density of the wood fibers, which achieved higher mechanical and technological attributes of MDF instead of solely enzyme-bonded MDF. The second step was industrial production (in cooperation with Pfleiderer AG, Arnsberg, Germany) with testing of all relevant attributes facing international standards. The first results of the production of boards (started in August 2006) were presented. The sustainable goal of the project was the reduction of using petrochemical binders in MDF production because of the rare and expensive fossil resources, which contribute to the ecological and economical aspects of the derived timber product industry.