Recycling of wood–plastic composites prepared from poly(vinyl chloride) and wood flour

This study emphasizes on closed-loop recycling of wood-plastic composites (WPC) which consists of two parts. The first part concentrates on re-processing industrial scrap of WPC profiles and its mixture with freshfeed. The ratio of WPC scrap:freshfeed at 30:70 was found to be the most appropriate. The second part involves recycling the WPC profiles up to seven passes. Reductions of the molecular weights of the poly(vinyl chloride) (PVC) matrix were detected due to the molecular chain scission of the shear stress during re-processing. Mechanical test results demonstrated that the WPC could be recycled as WPC again without critically affecting its mechanical performance.

► A significant molecular weight drop was detected upon re-processing for seven passes.
► The impact energy of the WPC freshfeed, scrap and their mixture were indifferent.
► The WPC could be recycled without critically affecting the mechanical performance.