
Creating a sustainable rubber from ordinary birch bark
Two-thirds of all rubber used in the world is made from oil. But now a sustainable process is being developed by a company named Reselo, which involves extracting rubber from birch bark. The bark itself is a residual product from today’s forest industry.

Extracting rubber from birch bark Photo: Reselo
Reselo is developing a process that isolates specific substances from birch bark to manufacture bio-based rubber. The bark is a residual product from the forest industry and the goal is to replace today’s fossil-based rubber that is used in everything from tyres to shoes, protective equipment and toys.
“The rubber we produce is entirely comparable to synthetic rubber. We currently work together with a wide range of sectors, from the automotive industry to shoe manufacturers, tyre manufacturers and rainwear manufacturers. We have an incredibly broad portfolio,” says Henrik Otendal, CEO and Founder Resolo.
Reselo currently has five full-time employees in Flemingsberg’s AWL innovation environment, where the company has found laboratories for their material development.
“Due to funding from the European Innovation Council, we quickly needed to find a place to scale up the business. AWL adapted their labs to suit our needs. Now a creative and dynamic lab cluster is emerging here of several companies similar to ours,” says Otendal.
The innovation behind Reseolo’s process is derived from a research project at KTH and the Wallenberg Wood Science Center. The project has been led by Thomas Baumgarten, who is one of the company’s three founders. During a startup event organised by, among others, STING, he met the two other founders, Otendal and Josefin Larsson.
“We complement each other in our different roles. Thomas provides the knowledge and development, and Josefin project manages our customer projects. And I’ve been focused on heading up the search for additional funding to scale our production.”
The customer portfolio is already international, although manufacturing is still at the prototype stage. Reselo has two smaller production facilities: one at Processum’s facility in Örnsköldsvik and one at Rise in Södertälje. Now they are looking for financing for full-scale production, preferably in conjunction with industrial companies that can contribute the raw material in the shape of the birch bark rubber.
“We’re looking at places simultaneously in Finland, Sweden and Canada, all of which have sizable forest industry sectors that need to refine residual products sustainably. Ideally, we’d co-located with a paper mill that already has much of the infrastructure we need.”
The aim is for the first customer products to be on the market as early as 2025/2026.
“We have an ambitious time plan, and at the same time we’re looking for additional funding, so we’re recruiting flatout.”
Reselo also runs the Swedish Bioeconomy Heros network, which includes a handful of similar companies specialising in sustainable biomaterials.
“Swedish Bioeconomy Heros is a way to help each other and share our experiences, knowledge and networks. It’s also difficult to cut through the static but we can help each other to do this.”
Companies in Swedish Bioeconomy Heros are all organised into what is now called deep tech, which includes companies that develop potentially revolutionary new technologies.
“Very few people understand the amount of time and work it takes to develop solutions in the deep tech segment, so it’s important that we help each other to succeed,” says Otendal.
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