The grip loop is made of natural fiber fabric and the attachments are made of bio-based materials. Source | Leki Lenhart GmbH

The German Institutes of Textile and Fiber Research Denkendorf (DITF) and Leki Lenhart GmbH (Kirchheim unter Teck, Germany) have collaborated on a project to develop a hiking pole made largely from renewable raw materials — in this case natural fiber composites. 

Consumers are increasingly asking for environmentally friendly alternatives to conventional materials. Aluminum and carbon fibers, for example, require a lot of energy to manufacture and are usually difficult to recycle. Therefore, the aim of the research project was to develop sustainable and durable sports poles made of hemp fibers and a bio-based matrix, which are manufactured using the pultrusion process.

The shaft of the final hiking pole product is made of regionally harvested hemp fibers that have been processed to rovings using the Kemafil-process — a wrapping process that gives the fibers a stable, rope-like structure through an interweaving technique. The matrix used was developed together with project partner Bio-Composites and More GmbH (Ipsheim, Germany) and is based on epoxidized linseed oil, which can be cured in the same way as a synthetic epoxide resin. The matrix is up to 42% organic and is ideal for the energy- and material-efficient pultrusion process. At DITF, approximately 16 meters of tubular profiles were successfully pultruded on a laboratory scale. The manufactured parts have a smooth surface and the natural fibers used are visible.

The suitability of the process for series production was demonstrated by manufacturing under industrial conditions at industrial partner CG TEC GmbH’s (Spalt, Germany) site.

Other components besides the shaft are also sustainable: The wrist strap is made of a natural fiber fabric and the attachments are made of a bio-based polymer. This means that more than 64% of the entire hiking pole is made from renewable raw materials.

Initial market analyses indicate very good commercial viability and user satisfaction. While hemp fibers have previously been used mainly in applications with low mechanical requirements, the DITF reports that the product proves that this natural fiber material is also suitable for resilient structures. The hiking poles manufactured achieve a bending strength comparable to that of aluminum poles and even offer improved damping properties. Thanks to its reduced carbon footprint, the product is sustainable and environmentally friendly.

The DITF thanks the Federal Ministry of Food, Rural Affairs and Consumer Protection in Baden-Württemberg for funding the Hanf-Profil research project.