From natural wood to high-performance composites: role of fiber treatment and graphene nanoplatelets

Abstract

Sustainable wood-epoxy composites were developed through wood fiber alkaline surface treatment and the insertion of graphene nanoplatelet (GNP). Swedish and pitch pine wood short fibers were the two types of wood used to strengthen the epoxy matrix. To enhance interfacial bonding, wood fibers were treated with two content of NaOH 5% and 10%. The epoxy matrix was supplemented with GNPs at weight percentages of 0.125 and 0.25. The results showed that composites reinforced with 5% alkali-treated wood fibers exhibited improved tensile, flexural and impact properties. However, increasing the treatment concentration to 10% led to a decrease in mechanical properties due to excessive fiber degradation. Also, the addition of GNPs gradually improved the mechanical properties; 0.125 wt% GNPs performed better than 0.25 wt% in terms of tensile, flexural and impact performance. These results show that the sustainable wood-epoxy composites with 0.125% GNPs have great potential for lightweight and eco-friendly applications, such as furniture, building panels, automobile interior parts, and other structural and semi-structural wood-based products that need improved mechanical performance.