Wood composites – that is, any wood material adhesive-bonded together – are the key material for several structural and non-structural app-lications for interior and exterior purposes, such as furniture, construction, floorings, windows and doors, etc. They can be successfully produced with predetermined specific properties matching the required end uses.
Use of wood-based-composites technology to create value-added commodities and traditional construction materials is generally accepted worldwide. Engineered wood- and lignocellulosiccomposite technologies allow users to add considerable value to a diverse number of wood and lignocellulosic feedstock including small-diameter timber, fast plantation-grown timber, agricultural fiber and lignocellulosic residues, recycled lumber, and timber removals of hazardous forest-fuels.
Another potential advantage of this type of economic- and materials-development scenario is that developing industrial composite processing technologies will provide producers an ability to use, and to adapt with, an ever-changing quality level of wood and/or other natural lignocellulosic feedstock. However, the current level of performance of our state-of-the-art engineered composite products sometimes limit broader application into commercial, non-residential and industrial construction markets because of both real and perceived issues related to fire, structuralperformance, and service-life.
From a performance standpoint, this developing knowledge has already and will continue to provide the fundamental understanding required to manufacture advanced engineered composites. From a manufacturing and a resource sustainability standpoint, with this evolving fundamental understanding of the relationships between materials, processes, and composite performance properties we now can in some cases, or may soon be able to, recognize the attributes and quality of an array of bio-based materials then adjust the composite manufacturing process to produce high-performance composite products.
Wood-based composites, including fiberboard, particleboard, plywood, wood composite sandwich panels, and laminated beams, need to be better studied and more attention should be paid to their research. Laboratories worldwide are carrying out innovative research, and new challenges, approaches, and ideas are continuously emerging, allowing for an exciting and interesting research future.
Wood-based composite materials are engineered and produced with tailored physical and mechanical properties appropriate for a wide variety of applications, known or not discovered yet. And indeed, the utilization of wood composites in various areas has increased recently due to their outstanding properties, allowing them to successfully and sustainably replace solid wood and other traditional materials.
In this Issue, we aim to highlight wood-based materials as an alternative way to improve basic material science through their latest advances. The latest advances in the development of wood-based composites are including reinforced composite structures, eco-friendly wood-based composites, wood-plastic composites (WPC), advanced functionalities in laminates, activation of natural fibers, natural matrixes, and other industrial research advancements in wood-based composite materials and their applications.
Wood composites are manufactured from a variety of materials. They usually contain the same woods that are used in lumber, but they are combined to make them stronger and more durable. Wood has long been used as a construction material and revered for its strength and natural aesthetics. However, with forests being chopped down across the globe to meet our insatiable demands, it’s time to look towards an alternative solution and wood composite may be the answer.
Wood composites including range of different derivative wood products, all of which are created by binding the strands, fibers, or boards of wood together. It’s also known as manmade wood, manufactured board or engineered wood, as well as wood-plastic composite (WPC) when using wood fibers and thermoplastics. Similar composite products can also be made from vegetable fibers using lignin-containing materials such as hemp stalks, sugar cane residue, and rye and wheat straw, with chemical additives enabling the integration of polymer and wood flour while helping facilitate optimal processing conditions.
The latest advances in the development of wood-based composites are including reinforced composite structures, eco-friendly wood-based composites, wood-plastic composites (WPC), advanced functionalities in laminates, activation of natural fibers, natural matrixes, and other industrial research advancements in woodbased composite materials and their applications.
They are fixed using adhesives and are engineered to certain specifications, resulting in a material that can have diverse applications. The best part about wood composites is that they can be created using wood waste materials and smaller trees, reducing the need to fell oldgrowth forests. Composite wood products can be used in a variety of different ways, including both home and industrial construction, and are often used to replace steel for joists and beams in building projects.
Their most wide spread use, however, is in outdoor deck flooring, but they are also popular for railings, fencing, benches, window and door frames, cladding, and landscaping work. While composite wood can be used in most applications traditionally using solid wood, it is also a popular material for making flat-pack furniture due to its low manufacturing costs and light weight properties.
One of the main advantages of wood composite is that because it is man-made, it can be designed for specific qualities or performance requirements. It can be made into different thicknesses, grades, sizes and exposure durabilities, as well as manufactured to take advantage of the natural strength characteristics of wood (and sometimes results in a greater structural strength and stability than regular wood). As a result, it can be used in a diverse array of applications, from industrial scale to small home projects, and enable more design.
Wood composites have also some disadvantages. Some of these, does require more primary energy for its manufacture when compared to solid lumber. Some particle and fiber-based composite woods are also not suitable for outdoor use as they can absorb water and be more prone to humidityinduced warping than solid woods. Another concern regarding wood composites is the adhesives used in their design with some resins releasing toxic formaldehyde in the finished product (particularly those made with urea-formaldehyde bonded products which is one of the cheapest and most common adhesives).
The plastic materials often used in the creation of wood composites also have a higher fire hazard when compared to solid wood products, due to their higher chemical heat content and melting properties.
AUTHOR: S. C. Sahoo, Scientist, Indian Plywood Industries Research &Training Institute, (IPIRTI)