|Nova Institut’s Michael Carus|
Manufacturers of bioplastics can resolve the problem of dosing natural fibres by using hemp pellets, according to a new Germany-based project led by the Nova Institut.
The Nova Institut’s Michael Carus said the project was set up because natural fibres cannot be easily fed and dosed in the plastic process, as they stick together. The partners decided on hemp as a material because only flax and hemp are grown as fibre crops in the EU.
Prof Dr Jörg Müssig (HS Bremen, Bionik) and his team tested the properties of the hemp fibres from German manufacturer BaFa before and after pelletisation, within the granulate and in the end product, as well as checking the mechanical values of test specimens and end products.
Carus said that as well as solving dispensing problems, hemp can also improve mechanical properties when used in a biopolymer.
“This is depending on the application but [the mechanical strength] often comes close to glass fibre reinforcement, for example, 30% glass fibre is equal to 40% natural fibre reinforcement,” he told European Plastics News.
The infeed of natural fibres in form of optimized pellets also leads to a more homogenous distribution of the fibres and lower fibre damage, and production is cheaper and more sustainable than that of plastic pellets, according to the project partners.
According to Carus, several companies, including big automotive and plastic processors, are using the new pellets for testing and will soon decide to use them on whether to use them on a commercial level.
As well as Nova and BaFa, the project partners include FKuR, H.Hiendl, Linotech and the Fraunhofer WKI.