Tag Archives: Flip Flops

Algae-based flip-flops seek to tackle plastic pollution

Flip-flops are the world’s most popular shoe — but they also represent a large percentage of the plastic waste that ends up in landfills, on seashores, and in the oceans. But now there might be a better alternative, as researchers have come up with biodegradable flip-flops entirely made from algae.

Credit University of California San Diego

Researchers from the University of California San Diego have developed polymer foams from algae oil that meet commercial specifications for midsole shoes and the foot-bed of flip-flops. They are sustainable, consumer-ready, and biodegradable materials that will eventually reach the shops.

“The paper shows that we have commercial-quality foams that biodegrade in the natural environment,” said Stephen Mayfield, co-author, in a press release.

“After hundreds of formulations, we finally achieved one that met commercial specifications. These foams are 52% biocontent, eventually we’ll get to 100%.”

The study was carried out in partnership with the startup company Algenesis Materials. They helped determine the right formulation for the commercial-quality foams and also to define the best way to make them biodegradable.

To do so, the researchers immersed the foams in traditional compost and soil, discovering it took 16 weeks for the materials to degrade. During that period, they measured the molecules shed from the materials to account for any toxicity. They also identified the organisms that degraded such foams.

“We took the enzymes from the organisms degrading the foams and showed that we could use them to depolymerize these polyurethane products, and then identified the intermediate steps that take place in the process,” said Mayfield.

“We then showed that we could isolate the depolymerized products and use those to synthesize new polyurethane monomers.”

This opens to the door to not just more eco-friendly flip-flops, but a new type of plastic product that is fully recyclable, the researchers argued. Plastic pollution in the oceans is expected to triple by 2040, according to a recent study by the NGO International Solid Waste Association, calling for action from governments and companies.

The researchers hope that the sustainable footwear, which is due to be launched through a major flip-flop brand next year, will cut the amount of plastic ending up in oceans and landfill sites. They estimated that over one billion flip-flops are made every year, accounting for major plastic pollution.

The challenge ahead will be the economics behind the production, which is something the team is trying to figure out with the manufacturing partners.

“People are coming around on plastic ocean pollution and starting to demand products that can address what has become an environmental disaster,” said Tom Cooke, president of Algenesis, in a press release.

The study was published in the journal Bioresource Technology Report.

Renewable flip flops: scientists produce the “No. 1” footwear in the world from algae

Students and researchers at the University of California (UC) San Diego want to fix our plastic problem, one flip flop at a time. They’ve developed and produced the first algae-based, renewable flip flops in the world.

Triton flip flops.

Image credits UC San Diego.

Their first prototypes, developed over the summer months in a York Hall chemistry lab, are pretty basic as far as flip flops go. They’re made of a flexible, spongy sole, a simple strap, and a trident logo. But between its projected cost of $3 per pair and carbon-neutral production process, they might just help change the world’s environments for the better.

Step-by-step

Flip flops are the shoe on Earth. An estimated 3 billion of them find their way into waterways and the ocean each year, constituting a major plastic pollution source for marine environments. That’s because 3 billion petroleum-based flip flops are produced worldwide each year, eventually ending up as non-biodegradable trash in landfills, rivers, and oceans around the globe.

“These are the shoes of a fisherman and a farmer,” says Stephen Mayfield, UC San Diego professor of biology, who headed the research work alongside professor of chemistry and biochemistry Skip Pomeroy. “This is the No. 1 shoe in India, the No. 1 shoe in China and the No. 1 shoe in Africa. And, in fact, one of the largest pollutants in the ocean is polyurethane from flip flops and other shoes that have been washed or thrown into rivers and flow into the ocean.”

Two years ago, the two professors and their graduate and undergrad students developed the world’s first algae-sourced surfboard. Along with a local surfboard blank manufacturer, Arctic Foam of Oceanside, they developed a method to make algae oil hard enough to replace the polyurethane foam core in a surfboard, typically produced from petroleum. It was a big success among the surfing community, which was looking for more sustainable and eco-friendly way to construct boards.

Starting from that research, the duo wanted to expand. Surfboards were “the first obvious product to make” from algae, Mayfield says, but adds that “when you really look at the numbers you realize that making a flip flop or shoe sole like this is much more important.” Seeing the success algae-based foams enjoyed with the 500,000 or so boards sold around the world yearly, they decided to try the same approach for the billions of pairs of flip flops and other footwear that reach landfills (or worse, oceans) each year.

“Depending on how you do the chemistry, you can make hard foams or soft foams from algae oil,” Mayfield explains. “You can make algae-based, renewable surfboards, flip flops, polyurethane athletic shoes, car seats or even tires for your car.”

Mayfield and Pomeroy applied their idea, dubbed Triton Soles, for a $50,000 proof-of-concept grant. They received the funding via the Accelerating Innovations to Market program, initiated by UC San Diego’s Office of Innovation and Commercialization and paid for with the help of local elected officials through State Assembly Bill 2664. The goal of the bill is to bring more laboratory inventions from the campus to commercial development.

From research to retail

Along with Michael Burkart, a professor of chemistry and biochemistry at UC San Diego, Mayfield and Pomeroy formed a startup company called Algenesis Materials. It employs some of the students working on the flip flops, offering them much-needed practical experience in a scientific project with real-world impact.

“Part of the challenge is that typically I’d make a discovery, publish a paper and that’s sort of the end of it,” Mayfield explains. “But the best invention that you keep inside the lab really isn’t valuable for the world. And the way you make that invention valuable is to turn it into a product.”

“Teaching chemistry in the classroom is sometimes like trying to teach soccer at the chalkboard,” Pomeroy adds. “In the laboratory, students are far more engaged when they’re actually trying to solve a problem. Most people will tell you that our students are really, really bright, but they don’t always have practical experience.”

“This is a way to provide them with that.”

As Algenesis Meterials’ first product, the Triton will represent the platform on which the faculty members and students will work to refine the chemistry and manufacturing process. In time, they hope the experience will allow them to replace more petroleum-based products, such as shoe soles, car seats, or tires. The lion’s share of our oil today is, after all, originated from algae — and it is Mayfield’s hope that “anything we can make from petroleum we can ultimately make from algae.”

Triton manufacturing.

Image credits UC San Diego.

The Tritons — and any other polyurethane items made from algae oil — are more eco-friendly than their petroleum-based counterparts because the carbon used to manufacture them is captured from the atmosphere, not sourced from oil reserves. The team is also looking to make them biodegradable by converting the algae oil into polyurethane while allowing the carbon bonds inside the plastic to be degraded by microorganisms. The end goal is to make flip flops that “can be thrown into a compost pile and they will be eaten by microorganisms,” Mayfield says.

“If we can make these products sustainable and biodegradable, we can impact not only San Diego, but every beach community on the entire planet,” he says. “In San Diego, we have this fantastic surfing culture, many of our faculty and students are surfers, and I think all of us understand because of that connection to the ocean how important the environment is.”

They plan to have the flip flops commercially available sometime in 2018.