Evaluation of Mechanical Energy Consumption in WPC Production from Pine (Pinus sylvestris) and Hemp (Cannabis sativa L.) with ABS Thermoplastic Additions

This study investigates lignocellulosic biocomposites' physicochemical properties and strength parameters with varying thermoplastic content. Biocomposites were prepared using wood (<i>Pinus sylvestris</i>) or hemp shives (<i>Cannabis sativa</i> L.) combined with 25% and 50% ABS regranulate. The research focused on evaluating the mechanical energy consumption during the compaction of wood-ABS biocomposites with different pine fractions pretreated with hot water extraction (HWE) and analyzing the relationship between strength and thermoplastic content. Results indicate that the composition of the mixture and the size of the hemp shives fraction did not significantly influence energy consumption during densification. Energy values ranged from 1.234 × 10⁻⁸ J to 8.296 × 10⁻⁸ J. While the densification of pine after HWE was unsuccessful without ABS, preheating the mixtures with ABS facilitated the production of a uniform composite. The work required for densification ranged from 1.404 × 10⁻⁵ J to 2.711 × 10⁻⁵ J for fractions without ABS. For mixtures with ABS, the work required was 1.954 × 10⁻⁵ J for fraction 0 ÷ 0.4 (f1) and 0.042 × 10⁻⁵ J for fraction 0.4 ÷ 0.8.