Influence of Pre-Impregnation Acetic Anhydride and Heating Time on Mechanical and Physical Properties of Wood-Plastic Composites

This research aimed to assess the influence of different pre-impregnation times (PITs) (60, 180, and 300 min), heating or reaction times (H/RTs) (60, 90, and 120 min), and chemical modification of wood flour (WF) on the mechanical and physical properties of wood-plastic composites (WPCs). The study employed acetylated beech (Fagus orientalis L.) flour as the filler and polypropylene (PP) as the matrix phase producing of WPC samples through melt compounding and injection molding. The resulting composites underwent testing for their physical and mechanical properties. The findings revealed that WPCs derived from acetylated wood with PITs of 60 min and H/RTs of 60 min exhibited the highest mechanical properties, except for the bending modulus. Moreover, the lowest water absorption (WA) was observed in the PITs-H/RTs combination of 60-120 min, while the lowest thickness swelling (TS) occurred in the PITs-H/RTs combination of 300-60 min. The simultaneous utilization of pre-impregnation and reaction times demonstrated a synergistic effect on the physical and mechanical properties. Consequently, the chemical modification of wood flour and the application of suitable reaction times improved the interfacial adhesion, thereby enhancing the overall performance of the WPCs.