Wood plastic composites have been in the market for almost 5-10 years, and are predominantly in the form of profiles for building and construction as well as recreation industries. These profiles are made using the extrusion process and are essentially developed from Polyolefins and wood. However, because of very high moisture levels, the wood requires predrying.

Newer applications are being processed and manufactured with various processes that are new for wood composites, like injection and compression molding and dual-belt forming. Demands exerted on the injection molding process are much more as the higher level of moisture in the wood tends to corrode the expensive molds. Since it is difficult to provide vent in the injection molding process, the material (wood) is required to be pre-dried. The injection molding process also demands the compound to have higher flow characteristics, and higher flow demands more properties. Due to these processing difficulties, the injection molding process would have only less than 10% share of these products. Extrusion continues to be the major process for natural fiber-plastic composites. It is also the most econmical.

Injection and compression molders are modifying their formulations and replacing some wood fillers with agricultural fibers like hemp, flax, rice hulls or wheat straw. Some are partially substituting mineral fillers like talc, and one patented process partially uses starch in place of wood. Blends of fillers reportedly can improve stiffness, creep resistance and other properties.

Compression molding tends to be more limited than other processes in throughput capacity, but it has the advantage of not breaking fibers. Compression molding can also incorporate higher wood loadings than injection molding.

Another new building product: flooring, is being developed with an unusual composite process. Called Thermofix, it is a a dual-belt forming technology developed by Schilling-Knobel GmbH in Germany. The process compresses composite pellets between two heated PTFE belts to form a continuous sheet, upto 20mm thickness. The granules are 60% wood flour and 40% flexible PVC and are produced in a Palltruder. The first commercial Thermofix line has been set up in the Czech Republic and a second will be set up in Canada to make wood-composite flooring from recycled carpet tiles.

Some of the newer products or applications of these composites that have been developed recently are:
Post ends, toilet seats, carpenter’s levels, door and window sills, office partitions, roofing shingles and flooring.