Development of wood-polymer composite by silanization: Analysis the thermal, physical and mechanical behaviors

Certain drawbacks of wood and wood-based composites, such as hygroscopicity, dimensional instability due to moisture fluctuations, and properties changes exposing environmental factors, often limit their service life and range of applications. It is well established that the properties of composites, including wood-polymer composites (WPCs), can be enhanced through the cross-linking of polymers with the wood substrate via coupling agents. In this study, the effect of the silane coupling agent (3-trimethoxysilylpropyl methacrylate) was compared under neutral and acidic conditions; subsequently, the optimally silanized samples, along with control samples, were impregnated with styrene and acrylonitrile. According to the results, silane modification under acidic conditions improved the resultant composite’s properties more significantly than under neutral conditions. Composites containing styrene, with more uniform and extensive polymerization, exhibited greater property improvement than those containing acrylonitrile. Morphological images of the co-modified samples indicated a greater extent of in situ polymerization for the vinylic monomers within the silanized wood lumens, without noticeable gaps from the cell walls. Among the co-modified samples, those containing styrene exhibited more significantly enhanced properties than those based on acrylonitrile. However, compared to their respective single-monomer modifications, the property improvement ratio for the silane/acrylonitrile composites to the acrylonitrile composites was greater than the corresponding ratio observed for the styrene-based composites.