A. A. Klesov

Bio: A. A. Klesov is an academic researcher. The author has an hindex of 1, co-authored 1 publications receiving 392 citations.

A review of wood thermal pretreatments to improve wood composite properties

Abstract: The objective of this paper is to review the published literature on improving properties of wood composites through thermal pretreatment of wood. Thermal pretreatment has been conducted in moist environments using hot water or steam at temperatures up to 180 and 230 °C, respectively, or in dry environments using inert gases at temperatures up to 240 °C. In these conditions, hemicelluloses are removed, crystallinity index of cellulose is increased, and cellulose degree of polymerization is reduced, while lignin is not considerably affected. Thermally modified wood has been used to manufacture wood–plastic composites, particleboard, oriented strand board, binderless panels, fiberboard, waferboard, and flakeboard. Thermal pretreatment considerably reduced water absorption and thickness swelling of wood composites, which has been attributed mainly to the removal of hemicelluloses. Mechanical properties have been increased or sometimes reduced, depending on the product and the conditions of the pretreatment. Thermal pretreatment has also shown to improve the resistance of composites to decay.

Fabrication and interfacial modification of wood/recycled plastic composite materials

Abstract: In this study, wood/recycled plastic composite (WRPC) material was fabricated with post-consumer high density polyethylene (HDPE) and wood fiber using a single-screw extruder. To improve the interfacial adhesion between the wood fiber and the HDPE, a coupling agent, maleic anhydride modified polypropylene (MAPP), together with three surface treatments (an alkaline method, a silane method and an alkaline followed by silane method) were used to treat the wood fibers. The surface chemistry of the treated fibers was evaluated using FTIR techniques. The effects of wood fiber length, weight fraction and surface treatment on the mechanical properties of WRPC materials were investigated. Fracture surfaces of tested WRPC specimens were examined and the fracture mechanism of WRPC materials is also discussed in this paper. Test results indicate that WRPC material with wood fiber treated by the alkaline followed by silane treatment method together with the MAPP coupling agent possesses good mechanical properties. The content of wood fiber affects the flexural strength, flexural modulus, and impact strength of these WRPC materials.