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Plastics are wonder materials that are used in countless applications, but there is one big problem: they will mostly be around forever. Not only is there the issue of what to do with plastic waste, but conventional plastics also break down into microscopic particles and leech toxins, both of which are bad for the environment. The answer to this problem is biodegradable plastics, but these resins can be expensive to produce and properly process.
Radical Plastics is a Massachusetts-based start-up company that has developed a promising plastic resin that breaks down over time into harmless carbon-based materials. If products made with the resin are exposed to weathering, a catalyst within it triggers a free radical reaction, which then cuts the long polymer chains found in plastic, and drops in oxygen groups. The final result is a biodegradable wax that serves as food for microorganisms. The wax is then metabolized into biomass, carbon dioxide, and water. While there are trace amounts of minerals, these are naturally occurring metals such as iron, copper, and manganese.
Where did Radical Plastics' Biodegradable Plastics Solution Begin?
The company was founded by two plastics engineers, Yelena Kann and Kristin Taylor, who have had decades of experience working with polymers in both academia and the private industry. The engineers were colleagues at the biodegradable plastics company Metbolix. They have said working for the company taught them about the requirements for biodegradable plastic, especially that it should be indistinguishable from conventional, non-biodegradable plastic. Currently available biodegradable plastics are often inferior in many ways to conventional plastics and have prohibitive costs.
In 2017, Kann was studying fine mineral-based soil conditioner that is a waste by-product of mining operations. She found that it could be used to make a catalyst that could break down conventional plastics. Kann tested the additive potential of this matter by integrating a small quantity into a film of the standard plastic polythene. She buried samples in her backyard, and after a few weeks, dug them up to discover they had started to break down.
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Six months later, Kann came back to her samples to find the experimental polythene film had further broken down into small, waxy flakes. Evaluating the flakes, Kann discovered they had different chemistry and lower molecular weight than the original polythene. Kann realized the experimental material could potentially be incorporated into the soil as a soil conditioner.
Agricultural Testing Ground
With decades of experience in the polymers industry, the Radical Plastics founders have targeted the agricultural market as the initial testing ground for the commercial viability of their product. The company has been working with a third party to validate that their resin can meet the standard for degradation of a soil additive, which says the material must degrade by 90% within two years.
Conventional plastics degrade to a certain degree in the natural environment but hit a point at which the process stalls. This often results in the creation of ocean-polluting microplastics. The catalyst in the Radical Plastics resin drives the natural degradation process.
With just 0.5 to 2% of it in a polythene film, the fine mineral matter used by Radical Plastics is the ideal catalyst for degrading the film further and more comprehensively than the biodegradable plastic currently available. The biodegradable plastics presently available are mainly starch-based, have inferior physical qualities, and are challenging to handle. Radical Plastics said it is targeting the agricultural market because its material offers the industry a functional benefit.
Radical Plastic acquired a notice of allowance for its initial patent in March 2018, and the company has indicated that there are more patents to come as it expands. It recently partnered with polymer company AlphaGary to create fully formed plastic pellets that are ready for use in various applications. Radical Plastics has announced that there will initially be three grades of resin available.
One of the main benefits of the new resin is that it can be recycled with polythene, a quality that Taylor deems essential for ideal end-of-life processing. She added that putting biodegradable products in a landfill is hugely problematic.
Taylor and Kann have said they are taking a cautious approach to market their product. Citing their experience in the industry, the Radical Plastics founders said they want to show decision-makers in packaging and other industries that their material is not only physically degrading but also chemically breaking down.
Radical Plastics has won prominent competitions, including the 2018 CleanTech Open, and has been cited as a 'company to watch.'
Learn more about Radical Plastics' solution in the below video:
The Issues with Conventional Bioplastics
As noted above, there are biodegradable plastics currently on the market. However, while they are considered more eco-friendly than conventional plastics, they are not without issues.
Although biodegradable plastics are made from natural agricultural products such as corn or sugar cane, a 2010 study from researchers at the University of Pittsburgh indicated that the number of pesticides and fertilizers used to grow the raw materials for biodegradable plastics considerably offsets the plastic pollution they eliminate. In addition, to meet the current demand for plastic would require vast swaths of land, and this would take away valuable property currently used for the production of food crops.
To completely break down into harmless by-products, most biodegradable plastics require the high temperatures of an industrial composting facility. Given that there are a limited number of these facilities, these plastics typically end up in a landfill, where they release methane. Another complication is the fact that if biodegradable plastics are incorporated into a batch of plastic recycling, it can ruin the batch, causing it to be sent to landfills.
Finally, one of the most significant issues with biodegradable plastics is their cost. Polylactic acid (PLA) is a biodegradable plastic that typically costs 20 to 50% more than comparable materials.
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The Future of Radical Plastics' Technology
Radical Plastics' solution hopes to revolutionize the field of biodegradable plastics and lead the way to greener options in a bid to fight again pollution in our environment. The company believes that: "By replacing existing, non-degradable plastics with biodegradable compounds from Radical Plastics, converters and brand owners can enjoy the outstanding properties of conventional plastics with the added benefit of complete biodegradability."
Radical Plastics plans to bring the technology to the single-use plastics and flexible packaging market by 2021.
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