The discovery of the recycled carbon fibre

and subsequent differently developed products

June 2016

In industry, carbon fibre reinforced plastics (CFK) as material for lightweight construction apply increasingly. This past trend of growth will last further in the future.

However, what happens to the waste products?

Two paper makers, Walter Reichel (Reso Oberflächentechnik GmbH, located in Mering/Germany) and Peter Helfer (helferpapier, located in Dachau/Germany), asked themselves that question.

After five years of development work and further training, they immersed themselves more and more into the characteristic of the carbon fibre. Through intensive studies and continuing laboratory tests they finally were acquainted with the carbon features. The carbon fibres are essentially distinct from the paper fibres in structure, charge and surface property. Nevertheless there was the provoking challenge to produce a plane product from these elastic fibres with the help of the wet-laid-procedure, in which the quality of the carbon needed to be kept. The biggest challenge during the project was to distribute the thin 7µm sized carbon fibres in a water based suspension smoothly and to position them during the production.

Through thermo-chemical cracking (pyrolysis) of the resin bonded carbon fibre reinforced plastics (CFK) it is possible to expose the carbon fibre again free of failure. In March 2012, a large-scale test was successfully conducted in the former pyrolysis plant Burgau with the collaboration of the paper makers and guidance of the bifa (Bavarian institute for waste management).  
Due to scientific analysis in carbon fibre paper (KOHPA®) the further developed Wet-Laid-Method allows a homogeneous dispersion together with paper fibres, even when using 100% carbon fibres.

The new product is electrically conducting and temperatures of more than 100°C can be reached through a not dangerous low voltage. The use as flat heating offers for example the advantage of energy saving by a minimal space requirement.
A further advantage of the flexible carbon fibre material is that the product keeps the paper character, stays furthermore smooth and can be shaped into forms and can be cut – same as paper. Besides the flexibility, the character of the absolute form stability under humid influence should be pointed out.

The laminating on stone, textiles or other material is applicated in the industry and is processed in caravan lightweight construction. The carbon paper can furthermore be used to protect against EM radiation as dissipation of static electricity.

Generally, it is common practice to process carbon fibres in a dry textile processing. Through the wet process engineering, a new uncomplicated method of production without any health threat is possible.

In addition, the principle of sustainability is fulfilled when using recycled carbon and paper fibres (waste paper).