Reselo advancing birch-bark rubber developments

Halmstad, Sweden – Reselo AB is attracting considerable industry attention following its success in a recent Nokian Tyres innovation challenge, CEO Henrik Otendal has reported.

In February, the Swedish developer of renewable rubber made from residue birch bark emerged as the winner from 50 entries to the tire maker's 'Fast Race, Big Change' competition.

The Reselo Rubber was said to have shown its “versatility and future potential” including in ice-track testing of tires at Nokian’s White Hell test track in Finnish Lapland.

As winner of the Fast Race, Big Change event, Reselo received a monetary prize as well as an opportunity to explore a business or development partnership with Nokian.

“We want to be part of their success story,” Teemu Soini, head of innovation & development, Nokian Tyres, said in the awards announcement.

“We believe that Reselo will be one of the stepping-stones towards our own goal of having 50% of the raw materials in our tires renewable or recycled by 2030,” stated Soini.

Asked about the company’s progress since the award, Resolo’s CEO Otendal commented: “We are, of course, running the project with Nokian Tyre since it was part of the award, and it goes very well.”

The Halmstad-based company is also “experiencing an overwhelming interest for our rubber from all kinds of companies using rubber,” Otendal added in written comments to ERJ.

Reselo, he said, is currently running a number of other validation projects with global customers, both in consumer goods and in industrial applications.

This effort is being supported by the company’s own laboratory in Stockholm, said Otenda, adding that “we have grown our team substantially.”

Meanwhile, he noted, the company is optimising and scaling up its capabilities for future production – helped, in part, by grant awarded received from the EU last year.

Reselo is also currently searching for investors to support the set-up of demo-scale production unit, according to Otenda.

“At the same time, we are looking for cooperations in Europe and Canada within the forest industry to secure our raw material,” the CEO concluded.

Founded in 2021, Reselo emerged from R&D work at the Wallenberg Wood Science Center in Stockholm to develop a process to produce biomaterials from birch bark.

According to Reselo, birch bark is a great feedstock for industrial-scale production of new materials, due to its high content of aliphatic compounds like suberin.

Suberin comprises a polymeric network of long chain fatty acids, aromatic compounds, and glycerol that form an extracellular barrier.

Besides many carboxylic acid groups, the long-chain fatty acids in suberin often have additional functionalities, including via hydroxy, epoxide groups.

As the functionalities can form specific covalent bonds, such as ester or ether bonds, suberin monomers are attractive building blocks to develop novel biopolymers.

During its research, Reselo found that heat-driven condensation of suberin generated a black elastomeric material with physical and thermo-mechanical properties similar to those found in natural rubber.

To produce the rubber, Reselo’s biorefinery processes birch bark sourced from the residue of the global pulp, paper and plywood industry.

A single mill, it says, can create 100 kilotonnes per annum (ktpa) of birch bark residue, while the forestry industry in Finland and Sweden alone can produce enough raw material for 200ktpa of rubber.

Also key to the sustainability of Reselo’s process is that its biorefinery approach can valorise all components of complex biomass – thereby producing a range of renewable substances under relatively mild processing conditions.