The Evaluation of Tree Bark as Filler for Wood-Plastic Composites: Experimental Study and Modelling

Abstract

Tree bark is one of the waste materials produced during harvesting. In this study, tree bark was evaluated for the production of WPCs. Three tree barks (Oak, Calabrian pine, and Cedar) were added to the matrix as an alternative for wood flour (20-80 mesh). Different tree bark content (10, 20, 40%) were also selected. The tree bark-based WPCs were produced with the flat-pressed method. The effect of tree bark on water absorption (WA) and thickness swelling (TS) were investigated during the 14 days. Tree barks have a significant effect on the WA and TS properties of the composites. As the bark content increased, the WA and TS values decreased. While the WA values increased up to 11.27% for control samples, it is only 3.27% for 40% of tree bark. Similar results were also observed for TS values. Also, the prediction models were developed using multiple linear regression (MLR). Correlation coefficient (R2) values of models were determined as 0.882, 0.853, and 0.850 for oak, Calabrian pine, and cedar WA values and 0.889, 0.839, and 0.879 for oak, Calabrian pine, and cedar TS values, respectively. The results showed that tree bark has the potential as an alternative to wood flour for WPC production.