Maleic anhydride copolymers as adhesion-promoting reagent in wood veneer/biopolyethlyene composite materials

Biocomposite materials consisting of biopolyethlylene (bio-PE) and wood veneer are produced using four structurally different maleic anhydride (MA) copolymers as reactive interfacial components. The respective MA copolymer was dip coated onto the veneer surface and serves as adhesion-promoting and compatibilizing reagents for the highly polar wood veneer and the weakly polar bio-PE. Fourier transformation infrared spectroscopy confirms esterification reactions on to the wood veneers. The MA copolymer modified woods show hydrophobic surfaces due to contact angles with water droplets up to 125 degrees. The adapted surface properties of the materials provide compatible biocomposite material verified by scanning electron microscopy/energy-dispersive X-ray spectroscopy images of wood fibers impregnated with the bio-PE matrix. Furthermore, the tensile properties of the biocomposite materials are greatly improved for all MA copolymer coatings. Compared to the unmodified wood veneer/bio-PE composites, the polypropylene-graft-maleic anhydride modification was found to have the highest improvement of 139% in Young's modulus and 115% in tensile strength. POLYM. COMPOS., 40:1979-1988, 2019. (c) 2018 Society of Plastics Engineers