More and more consumers are looking for low-impact purchases, even when it comes to fashion items like sports shoes. Footwear brands are adapting by offering products made from bioplastics or recycled plastics, marking the beginning of a long-lasting trend.
Nearly two years ago, news spread worldwide that Hollywood star Leonardo DiCaprio had been named a strategic investor in the British brand Løci, known for its vegan sneakers made from ocean-recovered plastic waste.
A risky investment choice? Not really, considering the growth prospects for the use of green or bio-plastics in the sneaker and sports shoe segment. Practical and comfortable for sports but increasingly worn on other occasions, sneakers have become true cult objects over the years, closely tied to the fashion world. And the numbers confirm this.
According to the latest estimates, around 50 billion pairs are produced globally each year. This is a rapidly growing market segment, projected to reach $95 billion in revenue by 2025.
Unfortunately, these products are not very sustainable, as more than half are made with plastic derivatives, from polyester to polyurethane, polyethylene to ethylene, and almost all end up in landfills, suffocating the planet. However, things are changing thanks to the growing green awareness of major brands, driven by consumer demand. So much so that, according to shoe design expert Nicoline van Enter, today's fashion imperative for sports shoe designers consists of three short words: less, less, less. Virgin plastic, of course.
Embracing Low-Impact Materials
Alongside companies like the Brazilian brand Veja or the Italian Id-Eight, which have started using bio-based materials partially or entirely derived from plant-based biomass, or natural materials like cotton and hemp, other brands have begun using recycled materials, including plastic, such as the French company Cog. Adidas has also taken a sustainable turn, committing to using only recycled plastic for all its shoes by the end of 2024.
Nike, since 2020, has launched the Space Hippie collection, featuring sustainable sneakers made from recycled plastic bottles, t-shirts, and yarn scraps. Timberland has followed suit, collaborating with the U.S. startup Thread, involving 1,300 Haitians in collecting abandoned plastic bottles and recovering PET to create a new fiber, which is then transformed into shoes, bags, and t-shirts.
Adidas has also collaborated with the association Parley for the Oceans, leading to the production of footwear made from ocean plastic waste. Meanwhile, Lotto Sport Italia has launched "Ohh!" sneakers, made in Italy with recycled materials. Specifically, their soles are made from worn-out tennis and padel balls, while the upper is derived from apple processing waste. Each pair of sneakers uses 1.5 tennis balls and 1.5 kg of apple processing waste, and even the laces and inner sole are made from recycled polyester and polyurethane. This project was developed in partnership with ReTurn Società Benefit, an innovative startup working in circular economy collaboration with the University of Padua, ENEA, and other research institutions.
A Growing Segment
It is clear that the green sports shoe segment is still underdeveloped but has excellent growth potential. "Not all plastics can be recycled, which represents a challenge for using green plastics in the footwear sector as a whole," explains Giuseppe Cozzetto, head of Gianeco, a Piedmont-based company operating globally in the recovery and trade of plastic materials, particularly thermoplastic elastomers and bioplastics. "Currently, various types of plastics are used to make shoes.
For example, polyurethane (PU), the most common in this segment, or EVA (ethylene-vinyl acetate), are excellent materials but have a life cycle that ends once the sole is molded, as they cannot be transformed into granules and reused to make new shoes. However, TPU, thermoplastic polyurethane formed by the polycondensation of an isocyanate with a diol, can be reused. The chemical nature of this chain influences the material's mechanical behavior and chemical resistance: the longer the chain, the more the material resembles natural rubber. Like all thermoplastic elastomers, TPU is elastic and processable in a molten state, making it suitable for extrusion, injection molding, compression molding, and blow molding."
TPU: A Promising Material
TPU is an elastomer resistant to abrasion, wear, and traction. It also has good flexibility and elasticity, allowing shoes to adapt to foot movements. It is lightweight and can be easily colored and customized, offering a wide range of design and personalization choices. "These qualities are particularly appreciated by major brands in the sector like Nike, Adidas, New Balance, Puma, Salomon, and Timberland, which use this type of plastic for soles, uppers, and elastic components in their footwear," continues Cozzetto. "Additionally, it is easily recyclable while maintaining characteristics similar to virgin TPU. This promotes a circular economy, as using recycled TPU for soles, uppers, and other elastic components helps reduce the amount of plastic waste destined for landfills or incineration."
It is no coincidence that TPU's growth trends are highly positive. "Moreover, TPU can be recycled both chemically and mechanically," adds Cozzetto. "This feature helps boost its market presence, which is expected to grow at least until 2032 in various industries, not just footwear." As long as it is certified, of course. "Companies using this material, as with other second-generation plastics, now demand traceability of its life cycle; they no longer settle for just words."
Challenges Under the Lens
There are still some challenges to overcome to expand the use of recycled plastic and TPU in the sports shoe sector, where they are currently used for soles, midsoles, uppers, and elastic components like closure straps, adjustable tongues, and elastic inserts. "The first difficulty is meeting customer expectations. Many major brands now have product lines made from green plastics, but to satisfy final consumers, who seek eco-friendly products with a good balance of quality and aesthetics, they often have to resort to mixed plastics," explains Cozzetto. "As a result, only a small portion of the material (30-40%) is recycled, with the rest being virgin plastic. This issue will likely be resolved over time with research and new technologies. We're on the right track."
The second challenge concerns the coloring of recycled plastic. "Currently, most green plastics for shoe soles are produced through mechanical recycling, resulting in regenerated black-colored material. This is a major limitation because companies producing white shoes struggle to find sufficient quantities of regenerated material. Currently, for every 10 tons of black recycled material, only two tons of white or transparent material (the best for recoloring according to fashion trends) are available," says Cozzetto. He concludes: "To overcome the coloring issue, chemical recycling would be needed, which is still rare in Europe and significantly more expensive than mechanical recycling at present."
More and more consumers are looking for low-impact purchases, even when it comes to fashion items like sports shoes. Footwear brands are adapting by offering products made from bioplastics or recycled plastics, marking the beginning of a long-lasting trend.
Nearly two years ago, news spread worldwide that Hollywood star Leonardo DiCaprio had been named a strategic investor in the British brand Løci, known for its vegan sneakers made from ocean-recovered plastic waste.
A risky investment choice? Not really, considering the growth prospects for the use of green or bio-plastics in the sneaker and sports shoe segment. Practical and comfortable for sports but increasingly worn on other occasions, sneakers have become true cult objects over the years, closely tied to the fashion world. And the numbers confirm this.
According to the latest estimates, around 50 billion pairs are produced globally each year. This is a rapidly growing market segment, projected to reach $95 billion in revenue by 2025.
Unfortunately, these products are not very sustainable, as more than half are made with plastic derivatives, from polyester to polyurethane, polyethylene to ethylene, and almost all end up in landfills, suffocating the planet. However, things are changing thanks to the growing green awareness of major brands, driven by consumer demand. So much so that, according to shoe design expert Nicoline van Enter, today's fashion imperative for sports shoe designers consists of three short words: less, less, less. Virgin plastic, of course.
Embracing Low-Impact Materials
Alongside companies like the Brazilian brand Veja or the Italian Id-Eight, which have started using bio-based materials partially or entirely derived from plant-based biomass, or natural materials like cotton and hemp, other brands have begun using recycled materials, including plastic, such as the French company Cog. Adidas has also taken a sustainable turn, committing to using only recycled plastic for all its shoes by the end of 2024.
Nike, since 2020, has launched the Space Hippie collection, featuring sustainable sneakers made from recycled plastic bottles, t-shirts, and yarn scraps. Timberland has followed suit, collaborating with the U.S. startup Thread, involving 1,300 Haitians in collecting abandoned plastic bottles and recovering PET to create a new fiber, which is then transformed into shoes, bags, and t-shirts.
Adidas has also collaborated with the association Parley for the Oceans, leading to the production of footwear made from ocean plastic waste. Meanwhile, Lotto Sport Italia has launched "Ohh!" sneakers, made in Italy with recycled materials. Specifically, their soles are made from worn-out tennis and padel balls, while the upper is derived from apple processing waste. Each pair of sneakers uses 1.5 tennis balls and 1.5 kg of apple processing waste, and even the laces and inner sole are made from recycled polyester and polyurethane. This project was developed in partnership with ReTurn Società Benefit, an innovative startup working in circular economy collaboration with the University of Padua, ENEA, and other research institutions.
A Growing Segment
It is clear that the green sports shoe segment is still underdeveloped but has excellent growth potential. "Not all plastics can be recycled, which represents a challenge for using green plastics in the footwear sector as a whole," explains Giuseppe Cozzetto, head of Gianeco, a Piedmont-based company operating globally in the recovery and trade of plastic materials, particularly thermoplastic elastomers and bioplastics. "Currently, various types of plastics are used to make shoes.
For example, polyurethane (PU), the most common in this segment, or EVA (ethylene-vinyl acetate), are excellent materials but have a life cycle that ends once the sole is molded, as they cannot be transformed into granules and reused to make new shoes. However, TPU, thermoplastic polyurethane formed by the polycondensation of an isocyanate with a diol, can be reused. The chemical nature of this chain influences the material's mechanical behavior and chemical resistance: the longer the chain, the more the material resembles natural rubber. Like all thermoplastic elastomers, TPU is elastic and processable in a molten state, making it suitable for extrusion, injection molding, compression molding, and blow molding."
TPU: A Promising Material
TPU is an elastomer resistant to abrasion, wear, and traction. It also has good flexibility and elasticity, allowing shoes to adapt to foot movements. It is lightweight and can be easily colored and customized, offering a wide range of design and personalization choices. "These qualities are particularly appreciated by major brands in the sector like Nike, Adidas, New Balance, Puma, Salomon, and Timberland, which use this type of plastic for soles, uppers, and elastic components in their footwear," continues Cozzetto. "Additionally, it is easily recyclable while maintaining characteristics similar to virgin TPU. This promotes a circular economy, as using recycled TPU for soles, uppers, and other elastic components helps reduce the amount of plastic waste destined for landfills or incineration."
It is no coincidence that TPU's growth trends are highly positive. "Moreover, TPU can be recycled both chemically and mechanically," adds Cozzetto. "This feature helps boost its market presence, which is expected to grow at least until 2032 in various industries, not just footwear." As long as it is certified, of course. "Companies using this material, as with other second-generation plastics, now demand traceability of its life cycle; they no longer settle for just words."
Challenges Under the Lens
There are still some challenges to overcome to expand the use of recycled plastic and TPU in the sports shoe sector, where they are currently used for soles, midsoles, uppers, and elastic components like closure straps, adjustable tongues, and elastic inserts. "The first difficulty is meeting customer expectations. Many major brands now have product lines made from green plastics, but to satisfy final consumers, who seek eco-friendly products with a good balance of quality and aesthetics, they often have to resort to mixed plastics," explains Cozzetto. "As a result, only a small portion of the material (30-40%) is recycled, with the rest being virgin plastic. This issue will likely be resolved over time with research and new technologies. We're on the right track."
The second challenge concerns the coloring of recycled plastic. "Currently, most green plastics for shoe soles are produced through mechanical recycling, resulting in regenerated black-colored material. This is a major limitation because companies producing white shoes struggle to find sufficient quantities of regenerated material. Currently, for every 10 tons of black recycled material, only two tons of white or transparent material (the best for recoloring according to fashion trends) are available," says Cozzetto. He concludes: "To overcome the coloring issue, chemical recycling would be needed, which is still rare in Europe and significantly more expensive than mechanical recycling at present."
