How Sustainability from Fiber Content in Wood-Polymer Composites Outweighs Lower Material Performance: An Industry Perspective

Abstract

There is increasing demand in the industry to make plastic-intensive products more sustainable. Wood-Plastic Composites (WPC) represent a plastic-substitution technology. They consist of up to 80% wood fibers by volume embedded in a petrochemical plastic matrix. The fiber content makes them ecological, but then also more expensive and susceptible to color change and water absorption. This study uses a choice-based survey of 167 German industry experts to clarify whether WPC could be used across sectors to increase the sustainability of their products and applications, up to what maximum wood content they would give up the advantages of pure plastic in favor of sustainability, and on which company factors and plastic-relevant attitudinal characteristics the choice depends. 85% of respondents agreed with WPC, regardless of their branch. Only 18.6% would accept cost increases for sustainability, and the majority (48.5%) preferred to renounce color stability rather than moisture resistance (18.0%). However, if higher moisture absorption was tolerated, the experts tended towards lower maximum wood contents (p = 0.001, r = -0.30). To fully exploit WPC`s eco-potential, future developments should optimize its hydrophobic properties rather than color stability. Due to low dependencies of the results on company factors, the marketing of WPC can be carried out under high standardization levels.