Is Rubber Biodegradable? And is it Sustainable?

Rubber is part of our daily lives. From rubber bands to car tires, containers, tools, and other rubber products, rubber is a commonly used raw material. If you’re eco-conscious or simply curious, you may wonder, is rubber biodegradable or non-biodegradable? How long does it take to decompose? Are rubber products environmentally friendly? 

In this article, we will look at this common raw material called rubber and answer those questions in your mind. 

What is rubber? 

Rubber is a natural material in its raw form derived from the sap of specific plants like Hevea Brasiliensis or rubber tree. The rubber tree produces a milk-like sap/natural rubber latex. Manufacturers make slight cuts in the tree bark to collect this natural latex rubber and collect the sap in cups. They transport the rubber tree latex to a facility and chemically transform it into rubber products. 

Rubber trees supply around 90% of the world’s natural rubber. What’s more interesting is that more than half of the rubber produced goes into making bike and car tires, vehicles, and airplanes. Whatever rubber remains is used to make shoe soles, toys, clothing, medical gloves, and other rubber products. 

Rubber is elastic in texture and can stretch and return to its original size without breaking. This makes it an ideal material for rubber bands, tires, and shoe soles.

Types of rubber

Today, manufacturers produce rubber products using four main types of rubber: 

Natural rubber

Natural rubber is a natural polymer, very elastic, and has a high recycling rate. Because manufacturers source it from a natural source, natural rubber is non-toxic and free of petroleum, heavy metals, or chemicals. 

Manufacturers use natural rubber to make shoe soles, tires, rubber balls, latex gloves, clothing, etc. 

Synthetic rubber

Due to the limited natural rubber supply during World War II, synthetic rubber production expanded in the United States. Synthetic rubber, also known as nitrile or butyl rubber, has a chemical structure that makes it resistant to harsh chemicals and fluids. 

Synthetic rubber is made from polymers derived from petroleum byproducts. Manufacturers mainly use this type of rubber in the automotive industry for tires, doors, belts, etc.

Silicone rubber is a type of manmade rubber that has water-repelling properties and high thermal stability. Manufacturers use silicone rubber for cookware, food storage products, electronics, etc. 

Neoprene rubber is another type of manmade rubber that manufacturers use for products like wet suits, life jackets, masks, etc. Neoprene rubbers have high resistance to chemicals and oils. 

Reclaimed rubber 

Manufacturers make reclaimed rubber from all types of rubber already used. The rubber undergoes processes like grinding, shredding, and melting before manufacturers use these grounds to make new rubber products. You will find reclaimed rubber in yoga mats, playgrounds, basketball courts, etc. 

Recycled rubber

Recycled rubber comes from the same raw materials as natural rubber. However, it requires a different manufacturing process, which is less energy-intensive than new synthetic rubber. Manufacturers won’t need to harvest a new rubber tree, and the chemical production process is eliminated.

Most recycled rubber materials are less elastic than new rubber materials. However, they are more eco-friendly.     

Natural rubber vs. Synthetic rubber 

Is there a difference between natural and synthetic rubber? Manufacturers use latex for natural rubber production, making it more eco-friendly. On the other hand, manufacturers derive synthetic rubber from petroleum-based chemicals for better durability. 

As demand rose in the 1800s-1900s, scientists began looking for synthetic alternatives to the limited natural rubber. During the outbreak of World War II, the natural rubber supply chain became limited in the United States. Without enough natural rubber to make military resources, the synthetic rubber industry began to emerge. 

While natural rubber comes from natural latex and is naturally resilient, it is not as strong as synthetic rubber. Synthetic rubbers can withstand higher temperatures, toxic chemicals, and degrading oils. 

However, natural rubbers are more environmentally friendly when it comes to environmental impact. Manufacturers commonly use sustainable natural rubber for making tires, while they use synthetic rubber to make rubber products like flooring tiles, surgical gloves, automotive parts, etc. 

Is rubber biodegradable?           

And now to the main question - is rubber biodegradable? Well, the answer depends on the type of rubber. A biodegradable material can break down in the natural environment. Microorganisms, oxygen, and other biotic factors turn these materials into water, carbon dioxide, and biomass. 

Natural rubber comes from sap that manufacturers derive from trees. They extract the sap, dry it, wash and send it out in sheets, which they then use to make rubber products. This means that natural rubber will decompose when thrown away. 

On the other hand, synthetic rubber does not share these same characteristics, and these rubber products can persist in landfills and oceans for years, creating significant rubber waste. One notable example is the rubber tire. People in the United States of America dispose of 280 million tires every year and only reuse 30 million tires.

Does vulcanized rubber biodegrade?

Vulcanized rubber is a type of rubber that goes through the process of hardening by heating through various means. Charles Goodyear discovered the vulcanization process in 1839. The most common vulcanization practice is the treatment of natural rubber with sulfur. However, today, it has grown to include the hardening of manmade rubbers. 

When manufacturers vulcanize rubber, the molecular structure gets altered, making the rubber more durable and resistant to wear and tear. Sadly, this comes at the expense of its biodegradation process. The sulfur vulcanization process, the most common process, increases the time needed for decomposition. This kind of rubber will decompose slowly, taking hundreds of years.  

Instead of dumping them in landfills, you can recycle vulcanized rubbers. For example, recycling facilities shred up tires and turn them into new products.      

How long does rubber take to decompose?          

Just because natural rubber is biodegradable does not mean the process of rubber degradation will happen quickly.

Latex is a natural and renewable resource. However, most rubber products have additives that can slow the decomposition process.  

While some rubber products may take weeks or months, others may take years. 

Is rubber eco-friendly?

So, is rubber environmentally friendly? Is rubber sustainable? However, it is easy to assume that it is eco-friendly because natural rubber comes from rubber trees. In reality, natural rubber production could be better. The natural rubber industry does come with some threats to our environment¹. 

Deforestation of rubber trees

Rubber trees are native to rainforests in South America. However, most of the natural rubber production happens in Asia. To meet the growing demand for rubber, tropical forests are being cleared out for rubber plantations². Southeast Asia lost over 1 million hectares to the production of rubber in 2012, which resulted in a loss of biodiversity in the region.

Read more: Deforestation Facts and Statistics.

Contamination due to pesticides and herbicides

The trees are also prone to pests and diseases. To protect the production of rubber, manufacturers use pesticides and herbicides. However, pests are not the only target. Both pesticides and herbicides can contaminate water, soil, animals, insects, and vegetation. Also, they can be toxic to humans.

Read more: Environmental Impact of Pesticides.       

Environmental pollution

Synthetic rubber is made from petroleum, a non-renewable resource derived from crude oil, which leads to significant environmental impact. Artificial rubber production contributes to air pollution. When heating manmade rubber, the toxic residue goes into the atmosphere. 

Also, manufacturing wastewater can be a major source of water pollution. Compounds like SBR and butadiene are non-biodegradable and, when in water, can consume lots of oxygen, increasing toxins and poisoning marine life. 

Are there any moves toward sustainability? 

While rubber has a negative environmental impact, it is not all bad news. Thanks to their Sustainable Business Program, organizations like the World Wildlife Fund (WWF) are working towards a sustainable rubber supply chain. 

Also, the independent Global Platform for Sustainable Natural Rubber (GPNSR) is an initiative that encourages a sustainable rubber industry. 

The organization monitors natural rubber plantations to ensure that farmers plant the right trees. They also work to ensure that the farming processes do not have any negative environmental impact like deforestation or pollution. To recover energy, the GPSNR also encourages the recycling of rubber. 

Some brands are also making a big difference by making sustainable rubber products. For example, brands like If You Care make household gloves using FSC-certified latex. These gloves are durable yet compostable and eco-friendly.    

How can you dispose of rubber? 

Millions of rubber products end up clogging our landfills, so proper rubber disposal is crucial for managing waste.

Not only does it reduce rubber waste, but it also helps to protect natural materials and our environment. 

You can dispose of rubber by refurbishing them. You can refurbish used products like tires or shoe soles, retread them and use them again. Another disposal method is to break them down and use them for other purposes, like mulch for playground surfacing. 

Manufacturers can also incinerate rubber to produce electricity in an environmentally friendly way. This disposal method controls emissions to reduce environmental impact. We have other advanced methods of rubber disposal, like pyrolysis and gasification. 

Can you recycle rubber? 

Yes, we can recycle rubber. Recycling rubber can help conserve natural resources and raw materials and reduce environmental impact. One common way facilities recycle rubber is by grinding. Recyclers break down old products into pieces and use them to make new products like rubber mats, tires, etc. 

De-vulcanization is another method for recycling rubber. Recyclers use heat and chemicals to break down bonds that make the rubber durable, returning it to liquid form. 

Some municipalities and companies have collection events and curbside pickups. If you have rubber materials you want to recycle, you can check in your locality for rubber recycling programs or pickups.  

Is rubber compostable? 

Items that need oxygen and microorganisms to break down are compostable. As microorganisms break down these items, they turn into organic waste, which can serve as nutrients for the soil. 

Natural rubbers come from plants and so are compostable. On the other hand, artificial rubbers are not. However, due to other materials included in the natural one, it will compost very slowly. 

While natural rubber is technically compostable, the practicalities of its composting are complex due to these additional components.

Synthetic rubbers, on the other hand, bear no compostability owing to their petroleum-based origins. They don't contain the biological constituents necessary for decomposition by microorganisms, rendering them unfit for composting.

Composting your rubber with commercial composting equipment at a composting facility rather than your composting bin at home is advisable. 

Rubber vs. plastic: Which is more eco-friendly? 

Many people sometimes associate rubber with plastic. However, they are different materials and have different chemical makeups. Isoprene is used to create rubber and synthetic compounds are used to make plastics. 

Rubber’s flexible texture makes it popular for rubber bands, tires, and gloves. These products are more durable and less likely to break or snap. On the other hand, plastic is lightweight and somewhat brittle. 

Depending on the materials used and how they are disposed of, both rubbers and plastics can harm our environment. As we have looked at earlier, manufacturers source rubber naturally. 

However, all plastics are manmade, and many are not recyclable. This leaves millions of plastics polluting our landfills and oceans. Also, most plastics do not biodegrade naturally. Overall, rubber is considered to be more eco-friendly than plastics. 

Eco-friendly rubber alternatives 

As we have looked at, rubber has a significant environmental impact. Thankfully, Some eco-friendly rubber alternatives are more sustainable. 

• Cork is a renewable natural resource from the bark of cork oak trees. Manufacturers can use cork instead of rubber products like shoe soles, flooring, or insulation. Innovators are also using cork fabric in the sustainable fashion industry. Cork is naturally anti-fungal and antimicrobial. They are also biodegradable and eco-friendly.
• Bamboo is another eco-friendly rubber alternative that manufacturers can use for flooring or textiles. 
• Thermoplastic elastomers and Mycelium are innovative alternatives to rubber. Both materials are biodegradable and compostable. Manufacturers can use them for insulation, automotive parts, and packaging.  
• Petroleum oil is a non-renewable resource. Vegetable oils like corn oil and soybean oil are plant-based oils that manufacturers can use as an alternative to petroleum oil used to make rubbers, similar to eco-friendly plastic (or at least more so).
• And for many rubber items, it's always best to go for reusable alternatives. For example, reusable water balloons for some eco-friendly summer fun and eco-friendly lunchboxes, many with silicone lids.

Final thoughts  

So, natural rubber is biodegradable. However, we can link deforestation and the toxicity of pesticides to the production of natural rubbers. Also, manufacturers add chemicals during production, slowing down the decomposition process. Synthetic rubber products contain synthetic substances that make them non-biodegradable. 

Overall, rubber can take several years to decompose in the environment. This leads to accumulated waste in landfills and oceans. 

Thankfully, it isn’t all bad news, as the industry is moving toward sustainability by using more eco-friendly raw materials, finding ways to recycle and dispose of rubber products, and employing sustainable production practices.