Swedish startup Reselo, backed by European Innovation Council, develops process to transform birch bark into a biomaterial it calls Reselo Rubber; it is produced from residual streams from forest and pulp industry and could replace fossil-based rubber

UMEA, Sweden , May 24, 2023 (press release) –

In the future, your shoe soles or car tires may be made of birch bark. The substance suberin, which is found naturally in birch bark, has proven to be a useful and sustainable alternative to oil in the production of rubber.

Text: Karolina Edstedt Photo: Erik Rahm & Christian Gustavsson

Interest in birch has increased significantly in recent years. The Swedish company Reselo has developed a process to transform birch bark into a biomaterial they call Reselo Rubber. The bark is run in a reactor where different components are separated and the substance suberin is then used to produce rubber. The material is produced from residual streams from the forest and pulp industry and can replace fossil-based rubber in the future.

»We have focused on consumer products and, above all, brand owners who make, for example, shoes, outdoor equipment and exercise equipment. Consumers are asking for sustainable alternatives and that pressure is getting bigger and bigger. Brand owners are also faster at transitioning than other types of industries that do not work with consumer products. But in the last two years, we have also seen a major change in attitude among companies that work with industrial applications such as car tires. They are looking more and more at climate-smart alternatives and it's great fun, says Josefin Larsson, product manager and co-founder at Reselo.

Reduces emissions

About two-thirds of the rubber on the market today is produced from oil. The remaining part is natural rubber and comes from rubber trees that are mainly grown in Southeast Asia. In the work of phasing out fossil-based materials, the need for a bio-based alternative becomes clear, Larsson says.

»It is not possible to replace all synthetic, fossil-based rubber with natural rubber. Partly because of the demands placed on performance, and partly because it competes simply with rainforest and food production in Southeast Asia.

With the help of the Swedish Environmental Research Institute, Reselo has made an early evaluation of the climate impact of bio-based rubber. It shows that you can save about four kilograms of carbon dioxide per kilogram of fossil-based rubber that you replace.

»Sustainability is a central part of our process development. The business concept itself is to replace conventional fossil-based rubber materials with bio-based ones and to make better use of the resources available, says Josefin Larsson.

Reselo was founded just over two years ago and has since grown from three people to five. Last autumn, Reselo received a grant of EUR 2.5 million from the European Innovation Council for process development and optimization and plans to gear up the business.

»It is still very early in the process, but we will set up our own lab this spring. It will be in the Stockholm area and there we will also have offices. We have hired a process engineer and also a polymer chemist to work with material development, so these are exciting times for Reselo.

The company aims to be able to produce and sell Reselo Rubber on a commercial scale in two to three years.