By-products of sawmill industry as raw materials for manufacture of chip-sawdust boards

The paper investigated the possibility of using sawmill industry by-products, i.e. chips and sawdust as raw materials for the production of building wood-based boards. We prepared three-ply boards with the outer layer made from two types of pine particles (A and B) with different dimensions, and the core layer containing a mixture of chips and sawdust at 70 : 30 or 60 : 40 wt ratio. The boards also featured different core layer (CL) to outer layers (OL) ratio of 70 : 30 or 60 : 40. The study demonstrated that unprocessed by-products of mechanical woodworking in the form of chips and sawdust are valuable raw materials for the production of wood-based boards. Irrespective of CL : OL ratio, the boards with the best properties were those with outer layers made of microparticles larger than the ones used currently in particleboard manufacture and with core layers containing 70% of chips. The highest bending strength, modulus of elasticity and dimensional stability of board was noted for CL : OL ratio of 60 : 40, while the highest internal bond was achieved for CL : OL ratio of 70 : 30. These boards may be used as non-structural elements intended for construction industry and interior decoration.