SecondSet gives tennis balls a second life and returns them to the playing court

Along with the net and the lines that mark the game, a perennial element on the tennis and paddle courts are the balls, even if they are not on the court. Their striking yellow color makes them stand out in any corner. They thus achieve the purpose of the International Tennis Federation (ITF, for its acronym in English), which in 1972 chose it, together with white, as an official tonality so that they would be more visible on television broadcasts.

The profusion of this color also caught the attention of Emilio Bello and Manel Risa, amateur paddle tennis players, when they saw that accumulated in waste containers of the sports centers or were left abandoned in their facilities. The reason is that after three or four games these balls reduce their pressure and are no longer useful. Its useful life is very short.

“We had been studying for a long time how to apply our experience in the world of marketing to projects with a positive impact. After considering several alternatives, we began to investigate what was being done with the used tennis and paddle balls and we identify a market opportunity”, Bello tells D+I.

This is how in August 2020 he was born SecondSet. Its objective is to promote the circular economy model in the sports sector by transforming a waste – in this case tennis and paddle balls – into a resource to manufacture new products.

To carry out the project, Ricard Martorell joined shortly after, as an expert in materials, to lead the research together with the team of Eurecat, the Technology Center of Catalonia.

A new, more resistant and flexible material

The annual world production of padel and tennis balls is approximately 325 million and only in Catalonia three million of this sports product are consumed. This translates into 200 tons of waste per year, according to Eurecat.

They are manufactured, mainly, with cross-linked rubber and felt made of polyamide or nylon. Both materials difficult to recycle and whose decomposition in a landfill would take more than 100 years. Nor is incineration advisable. Its reuse is thus presented as the most sustainable alternative.

“The felt, due to its thermoplastic nature, it is possible to heat it up to its melting temperature to obtain again the material in the form of pellets or pellets. From this you get yarn to make more felt or other types of fabrics ”, explains María Eugenia Rodríguez, director of the Composites Unit of Eurecat, to D+I.

“In the case of rubber, as it is a cross-linked material, when heat is applied it does not melt, which makes it more difficult to use it to re-manufacture balls from the residue. However, it can be used as filler inside a plastic to give it improved properties”. In both cases, Rodríguez points out that it is also possible to use it to manufacture injected or extruded parts.

In SecondSet they are working from recovered rubber. They study several formulations where the amount in their mixture with plastic has been varied and, although the resulting properties are different, they have observed a tendency to improved flexibility and impact resistance. “This new range of materials can be used to manufacture different types of pieces where one of the main objectives is to reduce rigidity”, clarifies Rodríguez.

Thanks to the versatility and properties of the material, it would be possible to use it in various sectors. However, Bello points out that “the main objective of SecondSet is to reintroduce materials in the sports sector and start with tennis and paddle tennis ”. And thus close the circle.

“The first results give us an orientation of what types of applications can be studied depending on the geometry of the piece, its functionality and objective costs”, concludes the Eurecat directive. Currently, the project is in the development phase.