Wood-plastic combinations with high dimensional stability

Wood-Polymer Composites

“…The WPC production necessarily goes through two different phases: monomer(s) is(are) first introduced into the wood pores by various methods depending on the properties of the wood being treated, followed by its(their) polymerization inside the wood (Din, 1989). The resulting product resembles natural wood, and its properties are a combination of wood and polymer material, i.e., applied to the wood components: improved hardness, abrasion resistance, compressive and bending strength, dimensional stability, resistance to biological degradation and others (Schaudy & Proksch, 1982). Such WPC typically find applications in high value wood products where their use may be justified in spite of their higher cost relative to wood.…”

“…Benzoyl peroxide were used as initiators for beech wood impregnated with trimethylolpropane trimethacrylate (TMPTA) and polyethylene glycol dimethacrylate (PEGDMA), and cyclohexanone peroxide were used to initiate the polymerization of styrene in birch wood (Ibach & Ellis, 2005;Ang et al, 2009). AIBN was used as an initiator under 80~110 o C to initiate the polymerization of methyl methacrylate (MMA), styrene (St), glycidyl methacrylate (GMA) within poplar wood (Li et al, 2009;2010a, 2010b2011a, 2011b (Schaudy and Proksch, 1982).…”

“…In hardwoods, pores (vessels) provide major longitudinal flow paths for fluids, while in softwoods, pits between pores and fibers, fiber lumens, and rays also play important roles in fluid flow, which commonly results in the poor impregnation of softwoods. Also, softwoods usually have lower density than hardwoods, requiring more treating chemical for comparable properties (Schaudy & Proksch, 1982;Schneider, 1994;Stolf & Lahr, 2004;Witt et al, 1977Witt et al, , 1981. In other words, most of hardwoods have the common denominator that they have a relatively open pore structure and minimum anmunt of pore blockage so that impregnant can be forced into the cell structure in a cost effective time frame.…”

“…16). The addition of isocyanate compounds with acrylic monomers reduces the brittleness of WPCs consisting only of acrylic compounds (Schaudy & Proksch, 1982). The toughness of WoodPolystyrene Composites modified by GMA and anhydride as crosslinkers and other mechanical properties as well as dimensional stability were all improved (Li et al 2011a).…”

Effects of Acid Copper Chromate Preservative and Hydrothermal Treatment on the Dimensional Stability, Hardness, and Decay Resistance of Poplar Wood

“…The dimensional stability of the treated wood is improved after treatment, which could be related to filling the void spaces in the wood (Schaudy and Proksch 1982;Ellis 1994;Zhang et al 2006) or because of a reduction in number of free hydroxyl groups with chemical reactions (Ellis 1994;Deka and Saikia 2000;Zhang et al 2006). For low-grade wood, the dimensional stability, mechanical strength, and decay resistance can be improved by wood modification (Yildiz et al 2005;Gao and Li 2007;Koubaa et al 2011).…”