Effect of fungal infection on physico-mechanical resistance of WPC made from thermally treated wood/PP

The effect of fungal decay on the physico-mechanical characteristics of thermally treated wood flour-plastic composites was determined. Firstly, the wood chips (Fagus orientalis L.) were treated thermally for 30 and 120 minutes at various temperatures (120, 150, and 180 °C) under saturated vapour in a steaming vessel and they were ground by Wiley mill machine. Then, polypropylene, thermally treated wood flour, and MAPP as compatibilizer were used by melt compounding and injection molding process. Some physical and mechanical parameters were measured prior to and after fungal (Trametes versicolor) infection for 6 weeks. The flexural strength, flexural modulus, and impact strength of undecayed and decayed WPCs at 180 °C for 120 min and at 150 °C for 30 min increased, respectively, but the water uptake and thickness swelling of WPCs decreased at 180 °C for 120 min. The wood particles of WPCs treated at 180 °C for 120 minutes had the least mass loss. The mechanical property parameters were reduced after fungal infection. Moreover, the results showed that the moisture sorption and thickness swelling for all formulations of unrotted specimens were significantly lower than that of white-rotted specimens.