Tyres get a green signal

It was an epiphanic moment for Hanson Cheng when he learned that tyre wear was the second-biggest source of microplastic pollution in the environment – after synthetic textiles. This was in 2020, and Cheng was doing a project on air pollution as part of a double Master's programme in Innovation Design Engineering conducted jointly by Imperial College London and the Royal College of Art. A conventional tyre consists of 15-25% synthetic rubber and 5-10% textile fibres — which are the source of microplastics in tyres — and 20-25% carbon black, which releases carbon dioxide, particulate matter and other harmful volatile organic compounds when it wears down on the roads.

Cheng and his two friends, Siobhan Anderson and Hugo Richardson, studied the problem but didn't find a solution to tyre pollution. So, they designed a shoebox-sized dust-collecting machine that could be installed behind the wheels. The idea was simple: the dust got collected in the device when friction between the road and the tyres electrostatically charged the tyre particles, which were attracted by the opposite charge provided by metal plates in the device. Based on this gadget, the trio founded their London-based start-up, The Tyre Collective, in 2020. The team is retrofitting the device in fleet vehicles and construction and maintenance vehicles to reduce their non-exhaust pollution. As the collected tyre wear in the machine needs to be taken out periodically — as in a vacuum cleaner — the team is partnering with companies to upcycle the tyre wear by reintroducing micro-rubber into tyres or shoe soles and carbon black as ink.