Considerations in recycling of wood-plastic composites
Wood-plastic composite decking has made major advances in material performance, processing and user acceptance. The growth of wood-plastic composite decking in North America has grown from less than 1 % in mid- 0's to over 10% today with growth projected by several studies to reach +20% before the end of this decade (2010). Preservative-treated wood decking experienced a very similar market entry and growth to market dominance over the 1970's and 80's in this same outdoor decking market when treated-wood supplanted naturally-durable redwood and cedar decking materials. Now that wood-plastic composites have become a major player in the North American decking market, many of the lessons learned in how treated-wood decking has historically been used, removed from service, and then discarded or recycled may help the wood-plastic composites industry and the recycling industry prepare for their future materials and their needs. This paper will discuss the materials and process issues of wood- plastic composites related to future recycling efforts. It will then detail how wood-plastic composite decking may be used and later discarded based on a combination of material property and durability issues, as well as consumer perceptions, needs, and non-performance issues. Each may significantly affect how soon and how much WPC decking material is removed from service. The recycling industry must be prepared to handle these materials in the near future.