FlexSea’s biodegradable plastics attract £3m investment

Using bioplastics derived from seaweed means that packaging and other products breakdown in the environment in a matter of weeks

FlexSea founders Carlo Fedeli and Thibaut Monfort-Micheo.
FlexSea founders Carlo Fedeli and Thibaut Monfort-Micheo.

FlexSea, a startup with its roots at Imperial, has announced the completion of a seed round worth £3 million in equity and grants. The investment will help the company commercialise a range of sustainable packaging solutions it has developed, based on plastics derived from seaweed.

The aim is to address the catastrophic impact of conventional plastics on the environment, in particular the single-use plastic products that persist in the ocean for many hundreds of years after they are discarded. In contrast, the biodegradable plastics devised by FlexSea will break down in the sea or the soil within a matter of weeks.

“FlexSea has the potential to change the pattern of human consumption of plastic and therefore change the sustainability path of our planet,” says Stephan Morais, Managing General Partner of lead investor Indico Capital. “We are proud to have led this investment and will back the founders in the next steps of product development, global partnerships, and commercialisation.”

Other participants in the funding round included RedRice Ventures, Btomorrow Ventures, Food Foundry, Vala Capital, ICON Capital, and Pente Capital. FlexSea has also won £1 million in grants from Innovate UK and other institutions.

“This investment will allow us to make significant progress and penetrate the market effectively,” says Carlo Fedeli, the co-founder and Chief Executive of FlexSea. “Indico has a significant track record of closely backing founders, and we are very happy to work together, and with our other investors, to take FlexSea to the next level.”

Red is the greenest solution

Mr Fedeli first started to think about biodegradable plastics during the COVID pandemic, while he was at home finishing an MSc in Innovation, Entrepreneurship & Management at Imperial College Business School.

“I noticed the amount of plastic packaging that was piling up at home, because of the online groceries and other deliveries we relied on at the time, and I just had enough,” he says.

plastic products in jars
FlexSea’s plastic comes in all shapes and sizes.

He started looking into the biodegradable plastics that were already available, and found that they often had shortcomings. Some didn’t actually break down very rapidly under day-to-day environmental conditions, while others involved unsustainable production methods. For example, plastics derived from seaweed are often made from brown seaweed, which is usually harvested from nature, rather than the commonly cultivated red seaweed.

“If you want to make a sustainable material, why not use the most sustainable source for it, which is also the most abundant right now?” he asks. So he set out to develop a thin-film plastic from red seaweed. “By the end of lockdown I had the first prototype, a transparent flexi-film, and that is still the backbone technology of our solvent-cast thin films,” he says.

FlexSea was set up in 2021 with co-founder Thibaut Monfort-Micheo, who had just finished a Master’s degree in the Department of Materials at Imperial. Their first home was at Scale Space, on the White City Campus, and they received support from across Imperial’s enterprising ecosystem. In 2021 they joined the Centre for Climate Change Innovation’s Greenhouse Accelerator, which has since evolved into Undaunted, and in 2022 they took part in Imperial’s Venture Catalyst Challenge, winning the energy and environment track.

Films, filaments and pellets

Along the way, the company has developed two lines of bioplastic: thin transparent films, for use in food and non-food packaging, and filaments and pellets for use in extruders, injection moulding devices and 3D printers to produce rigid and semi-rigid items. These materials are not only completely biodegradable in marine and soil environments, but also home-compostable within 8-12 weeks.

Meanwhile, the production process behind FlexSea’s biomaterials avoids the use of harsh chemicals and high temperatures, instead relying on renewable and natural ingredients. All production scraps and offcuts are recyclable, providing a closed-loop solution.

It was this rapid progress that convinced Lian Michelson, Investment Director at Vala Capital, to continue supporting FlexSea after leading its £200,000 pre-seed round in April 2022.

“In a short space of time, and with very little funding, Carlo and Thibaut had created an advanced prototype material, considerably increased their production capacity, filed their first IP and started initial paid pilots” – Lian Michelson Vala Capital

The next steps for FlexSea are to complete R&D into the different products it might offer, and decide on the first to take to the market.

seaweed to film
FlexSea takes seaweed and turns it into plastic film.

“This is a turning point for the company, and a great reward for the hard work and dedication of the whole team of 10 amazing people, who will benefit from this funding in their everyday research and development activities,” says Mr Monfort, FlexSea’s Chief Technology Officer. “We are heavily investing in equipment and machinery for in-house R&D, speeding up the process tremendously.”

Meanwhile, the grant funding from Innovate UK will support work on a complementary technology, to address waste produced when the valuable products, called hydrocolloids, have been extracted from seaweed.

“Now we are developing a technology to use that biomass, valorise it, and to increase the circularity of the whole seaweed industry,” said Mr Fedeli.


Imperial College London, press release, 2023-10-04.


Imperial College London
Innovate UK


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