Run is a devastating sport. Every year, they produce billions of shoes, they carry until they begin to break down and throw into the landfill. It is estimated that every year, in the United Kingdom, 300 million pairs of tennis shoes are rolled out.
In a long-term plan to avoid excess rubbish, adidas reconfigures its factories to produce footwear that can be cut into pellets, twist and turn into new trainers. The first experimental shoe of this kind is Futurecraft.Loop.
At first glance, running shoes do not look too different from any other. This is an all-round coach that is made up of all the usual components: foam padding, outer sole, knit upper, insert, ties and torsion bars added for stability.
Where the Loop does not stand out in how it is made – and reworked. Adidas engineers made a whole pair of shoes from a single material, a version of thermoplastic polyurethane (TPU). On average, other adidas coaches are made of at least 12 different materials. "The concept is that this shoe can be 100 percent recycled and that there is no waste," says Tanya Sahanga, Futurecraft's adidas team engineer who previously experimented with 3D print instructors and trained engineers of plastic pollution from the ocean.
"We're returning to the footwear of the first generation," says Graham Williamson, Senior Director of Adidas Department of the Future and leading the Loop project. "We will recycle and use this recycled material to create the components for the subsequent shoe."
To recycle the shoes, adidas handled them and dispatched them to one of their ASF industrial partners. When they arrive here, the material is chopped into fine pellets and then ripped back to the original condition from which it can be turned into a shoe.
Most importantly, TPU can dissolve when used. TPUs are one type of plastic polyurethane and are considered to have elastic properties as well as being transparent and generally resistant to oils and fats. This is not the first time that the company used a TPU variant in their shoes; In February 2013, adidas introduced its Boost foam, which is used in most midsoles, after working with a German BASF chemical producer.
When used in midsole, Boost is formed of 2,500 elastic TPU beads that are compressed into the mold to create an unmistakable appearance of rice cake. "The upper part is made of the same material," says Sahanga for Loop. (It's a grayish color because there is no chemicals that lighten, which coaches usually give an intact white look, she says). The problem for her team was that the TPU could relatively easily be manipulated into the substrate by turning it into a thread that can be used to make the upper shoe much more challenging.
The project breakdown, which lasts six years, came in 2016 when engineers modified plastics so that they could turn into a traditional fabric chain. "TPU yarn is available in the market, but we developed one specific for us and we have progressed," explains Sahanga. Previously, adidas did not have the material it could use to produce the entire shoe – traditionally the upper parts of the shoe are made of polyester.
"At the beginning of 2017, we were able to replicate shoes and components, before that we could only make one or two shoes at a time," says Sahanga. "We made a pile of 50."
Creating a new kind of yarn for the upper was not the only question. The adhesive that matches the shoes can not be easily degraded during the recycling process. Workers who make shoes with adhesives must wear masks to protect themselves from evaporation. To overtake it, adidas completely removed the shoe adhesive. Instead, it uses laser to weld parts of the shoes together.
Technology has been developed through its first speed factory in Germany. There are now two speed factories, the other one in the United States, and the robots make adidas trainers in less than a day. The factories enable adidas to move faster with production and subtract a certain reliance from factories in Asia, where more than 90 percent of 360 million trainers are produced every year.
Traditional factories can be environmentally ineffective. Landfills and environmental impacts are a big problem for sports makers and the fashion industry as a whole. A 2012 study conducted by researchers at the Massachusetts Institute of Technology has shown that one running shoe can include 65 individual parts, all of which normally end up in the landfill.
Although shoes can already be recycled, Adidas's effort is different because it uses materials to create brand new shoes that are designed for performance.
But it's not alone. Nike has a recycling scheme called Grind. The company takes old shoes from any manufacturer, throws them into a machine that will break them, and then use floor coverings. 18 different materials were used to create indoor basketball courts, playgrounds and astroturf soccer fields.
Minimalist shoe manufacturer VivioBarefoot has constructed shoes using recycled algae and works on a line of plant production that includes industrial maize material.
Forward, Loop could change the way Adidas works in full. Boost material is used in a variety of footwear styles, not just those designed for runners. There is also the potential for a new business model, which could include the possibility of subscription on shoes. Worn running shoes can be replaced automatically by a recycled model after a certain number of miles. The used pair would then be dissolved and shipped as a new product.
But it's still far away. At this point adidas needs to make loop scalable. So far, only a few hundred shoes have been tested by their own staff. As he announced shoes, he also distributed 200 pairs of journalists. Everything will be recycled. Those who were internally tested have all been subjected to standard shoe tests that have passed over 500 miles of roadblocks.
"For the recycling industry this is peanut," says Sahanga. "We're talking about one to five tons – that's nothing. These guys handle three-digit tones." Williamson adds that adidas expects the entire recycling and processing process to last about six months. This is because there is no speed factory technology within its Asian factories. "It's focused on working with multiple materials, multiple shoe components inside the assembly process that involves a lot of sticking," he says.
The company expects to offer limited commercial shoeing by the end of 2020. At that point this could be the last running shoe you are buying.
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