Utilization of demolition wood and mineral wool wastes in wood-plastic composites

Wood and mineral wool fractions from demolished buildings were sorted into different categories and processed to the suitable grain size needed for the manufacturing of wood-plastic composites. Processed construction and demolition waste materials mixed with plastics and additives were extruded into hollow test bars using a conical rotary extruder. Test specimens needed for measurements were cut from test bars. The results showed that the mechanical performance of wood-plastic composites based on construction and demolition waste wood, and mineral wool was at a good level and comparable to commonly used wood-plastic composites in decking applications. The highest strength properties of wood-plastic composites were achieved with a plywood fraction and the lowest with materials containing a particle/fibre board fraction. The mechanical performance can be improved by utilizing mineral wool in the formulation of wood-plastic composites. A material mixture containing several wood fractions as well as mineral wool also gave good strength properties. Only a minor reduction in strength properties was measured when recycled plastic was utilized meaning that wood-plastic composites suitable for many types of applications can be produced entirely from recycled materials.