Sustainability of WPC materials

Abstract: Is WPC a green material? How sustainable is the WPC? If you are interested, you can read the article below, where we will provide you with the most comprehensive answers to help you choose an eco-friendly WPC

Wood plastic composites (WPCs) are engineered wood products that recycle wood flour or fibers from different stages of other timber products. Wood plastic composites (WPCs) are largely sustainable because the used wood waste keeps the trees’ carbon sequestration and doesn’ t contribute to more deforestation. However, they are most sustainable if their plastic component is recycled or bio-based and their additives are natural-based.Wood is largely a sustainable material because of timber trees’ carbon sequestration potential. And using wood waste for WPCs increases the material’s environmental benefits.

What Are Wood Plastic Composites Made Of And What Does This Mean for Sustainability？

In the most simplistic sense, wood plastic composite contains three components:

Wood flour or fiber (i.e., the wood part)

Thermoplastics (i.e., the plastic part)

Additives (to bind the wood and plastic parts, strengthen the product, fill the gap, etc.) 

We will look at each of these for their sustainability.

The wood component in WPCs is generally in the sawdust form or small fibers. Wood accounts for between 50 to 70% of the total weight of the WPC.

In most cases, wood fiber or flour is utilized from waste materials – chips and shaving leftover after sawing lumber for other products. Maple, oak, or pine are common types of sawdust.

Small pieces of virgin wood are sometimes used to make large panels of WPCs. Smaller trees don’t provide lumber in the oversize occasionally needed in construction. Consequently, wood plastic composites are the solution.

Utilizing wood waste is favorable for the environment because it doesn’t contribute to deforestation.

Using smaller pieces of wood (instead of cutting down bigger, older trees) has lesser negative ecological impacts. The reason is that big, old trees play a more significant role in supporting wildlife.

Wood plastic composites use thermoplastics – a kind of polymer. Here are some thermoplastics commonly used in WPCs:

PE

PVC

PP

Polystyrene

PS  

PLA

The biggest share in the WPC market is Polyethylene (PE), of which manufacturing depends heavily on fossil fuels. Other fossil-based plastics used in WPCs are PVC, PP, and PS.

• Though most thermoplastics used in WPCs are derived from fossil fuels, there are also 100% bio-based options.
• Too, using recycled plastics results in more sustainable WPCs.

For example, PLA is biodegradable, biocompatible, and renewable thermoplastic derived from corn starch.

WPCs made with these types of thermoplastics can be all-natural and, in some cases, biodegradable. Research showed that sourcing bio-based polymers improved sustainability compared to conventional wood plastic composites.

Another alternative is to use recycled plastics to make new WPCs.

Additives are used to bind wood fibers and thermoplastic polymers, strengthening the end products and creating desired features.

Synthetic additives used in wood plastic composites often come from non-renewable resources (i.e., oil and gas) and carry several problems, including health risks and recycling challenges.

For example, common binding agents tend to contain formaldehyde, which releases potentially harmful gas (Volatile Organic Compounds) into the air over a period of time. This process is called “off-gassing,” and a high-level exposure can cause skin rashes, shortness of breath, wheezing, and changes in lung function.

Not all glues containing formaldehyde have the same level of off-gassing in terms of quantity and duration. Phenolic resin has a much lower emission than urea-formaldehyde resin.

Though formaldehyde at a high level is toxic, the off-gas release is often very small once the adhesive is set and cured. Engineered wood panels with added formaldehyde are safe to use once it has time to air out and/or sealed (with an appropriate coating).

Natural-based solutions tend to be better for the environment for two main reasons: 

• No risk of letting off Volatile Organic Compounds (VOCs)
• The possibilities of wood composite panels being biodegradable and recyclable 

Where Are Wood Plastic Composite Components Usually Sourced From

Using wood waste to make wood plastic composites doesn’t contribute to further deforestation. However, the harvesting method still plays a significant role in the overall sustainability of WPCs.

Here is the list of woods from tropical forests, some of which are the world’s richest in biodiversity. You need to purchase these woods with caution, whether it is in the form of natural wood or wood composite panels:

• Mahogany 
• Ipe 
• Cumaru 
• Tigerwood 
• Rosewood 
• Meranti
• Cocobolo
• Ebony 
• Merbau 
• Wenge 
• Teak

The rule of thumb for you as a consumer to tackle problems caused by illegal logging is to source sustainable woods. We will point you in the right direction with wood plastic composite at the end of this article.

According to a study of wood plastic composites containing bio-based polymers, the amount of CO2 generated by the processing of the composite material is partially or completely compensated by the carbon uptake during the growth phase of the plants used as raw materials.

How Sustainable Is the Usage of Wood Plastic Composites？

Using wood plastic composites can be sustainable thanks to the carbon capture storage in the products.

WPCs have excellent resistance to cracking and splitting. These composite products can last longer than equivalent solid woods in outdoor environments because they are stronger and less prone to humidity-induced buckling. Similarly, WPCs are often used as a replacement for MDF (Medium Density Fiberboard) and particle boards in high humidity areas.

Some varieties of wood plastic composites are biodegradable, while some others can be recycled at designated centers, extending the carbon storage role of this wood plastic composite.

How Sustainable Is the End-of-Life of Wood Plastic Composites？

The end-of-life stage for wood plastic composites is not as sustainable as natural wood because most of these products are non-biodegradable. However, many products can be recycled. Also, some 100% bio-based WPCs are bio-degradable, which is the most sustainable scenario for the end-of-life stage.

There are some scenarios for wood plastic composite panels at the end of their life:

They can end up in landfills and don’t decompose. In this case, it keeps its role as carbon storage.

Some WPCs are made entirely from biomaterials and can be left to decompose naturally at the end of life.

Some WPCs can be recycled. Reusing the thermoplastic polymer(s) improves the overall sustainability of WPCs.

Final Thoughts

Buying sustainable wood also means helping to prevent illegal or unsustainable logging, which harms the forests’ biosystems and accelerates climate change.

You can buy wood plastic composite as an alternative to solid wood and engineered wood panels like MDF or LDF. WPCs are an excellent way of utilizing wood waste. However, you need to ensure that the wood component comes from sustainably managed forests. Also, opt for the increasingly-available options of either bio-based or recycled polymers. Most importantly, use wood plastic composites for as long as possible, upcycle the material to extend its usage, and arrange it to be recycled appropriately.

Choosing WPC provided by Aludream allows for the maximum reduction of environmental pollution and enhances the sustainability and durability of WPC.