Lignum vitae wood-derived composites for high lubricating performance

Natural wood is a clean and environmentally friendly material. However, the wood used for tribological applications has been gradually replaced due to the unsatisfactory lubricating performance. Herein, a novel process for achieving high lubricating performance wood-derived composites has been proposed. The Lignum vitae wood was chosen as a representative, where its lignin is firstly removed and then followed by polydimethylsiloxane (PDMS) vacuum infusion. The experimental results indicated that the unique soft-hard composite structure was formed by the wood fibers and the infused PDMS of the PDMS infused Lignum vitae-derived composites (PDMS-L). The PDMS fitted the rough peak of the copper ball through large deformation and the interlayer PDMS reinforced fibers provided strong support, thus the PDMS-L presented great lubricating performance. The friction coefficient and the wear depth decrease significantly after PDMS infusion. Compared to the original Lignum vitae, the maximum reduction in the friction coefficient and the wear depth of the samples after the PDMS infusion is 85.2% and 79%, respectively. This study shows the potential of wood for tribological applications and provides a new avenue toward lubricating performance improvement for wood-derived composites.