IN 2010 Mathieu Flamini launched start-up GFBiochemicals as a side-project to his football career.
The Paris-based company's aim was to find a green alternative to petrochemicals, which can be found in plastics, rubber, and even shower gel.
Some 13 years on, Flamini has kept a 60 per cent stake in the business - while landing the CEO job.
According to Forbes, the former Arsenal star - who was a Champions League runner-up with the Premier League club - now has a net worth of £10billion.
Flamini, now 39, set up the company when he was just 25.
He has also found time to launch another business called Unity Performance Lab with former team-mate Mesut Ozil.
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It is a digital health, fitness and lifestyle community that fuses evidence-based performance and wellness advice with expert guidance from elite athletes, coaches and academics.
However, it's his first business that aims to save the planet.
“As a child I had two passions: football and sustainability," he told .
"I grew up in Marseilles near the sea, and was aware of the environmental questions around ocean plastics and chemical pollution from a very young age."
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Flamini and business partner Pasquale Granata met with scientists in Milan with an idea of founding an operation that promoted sustainability.
He revealed: “We didn’t know if it’d be energy, chemical or urban recycling, and we just ended up meeting with a team of scientists in Milan and started moving in that direction.”
GFBiochemicals take biomass, which could be manure or household waste, and turn it into levulinic acid.
Levulinic acid is seen as a potential replacement for petrochemicals, which are found in everyday items such as detergents and skin care.
According to research by the University of Maastricht, levulinic acid could reduce the CO2 made from manufacturing those products with petrochemicals by up to 80 per cent.
Top secret
Flamini, who was starring for Serie A side AC Milan when he set up GFBiochemicals, decided to keep his venture away from his team-mates.
“I was questioning myself, and I didn’t know which direction the business would go in," he said.
The three-cap former France international also said being a footballer didn't help his cause.
He said: “When you’re a footballer and you’re in a meeting talking about chemicals or sustainability, there is even more pressure on you.
“People really want to test you and see if you’re going to be able to deliver — because you’re not a businessman. I had to prove myself more than anyone else in the room.” Was this annoying? “Obviously it can be, but I took it as a challenge.”
CEO
Last year, GF Biochemicals received a major cash injection.
Sofinnova Partners, a leading European venture capital firm in life sciences, specialising in healthcare and sustainability, and investment company Sparta Capital ploughed $15million (£12.3million) into the group.
Flamini kept a 60 per cent stake and was made CEO.
"Now the question is when do I not work,” he explained.
“When you’re an entrepreneur you have to be dedicated and you don’t count the hours. I’m not working when I sleep, but for the rest of the time I’m available."
And he feels just like teen environmentalist, Greta Thunberg.
“I feel like I’m part of this effort of the younger generation like Greta Thunberg that’s setting up the future,” he said.
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"Although at the age of 15 I can guarantee you I was not in the street fighting for my future."