Hot pressing of wood fibers is an exciting and growing area of research. In September there was a start-up meeting in the project "Manufacturing processes for strong hydrophobic bio-materials using hot pressing technology". Tove Joelsson leads the project and MoRe Research also coordinates the project, which is financed by Bioinnovation. There are exciting project partners such as Mittuniversitetet, FSCN Research Centre, IPCO, Flooré AB, Re-board Technology, Ecohelix and Gludan.
Text about project from Bioinnovation's website:
This project aims for a shift towards renewable raw materials and higher resource efficiency in the building and construction sector. The raw material comes mainly from high-yield pulp, manufactured in a process where more than 80% of the wood substances are retained in the pulp. This provides a more efficient use of the forest and results in larger volumes of bio-based materials being able to replace fossil-based materials in case of certain forest growth.
The lignin, which makes up up to 30% of the wood material and acts as the glue in the wood fiber material, is used here to create water resistance and wet-strong bonds via a hot pressing technique. The technology takes advantage of lignin's very good binding/adhesion potential at high temperatures. In previous research into papermaking from lignin-rich pulps, it has been shown that lignin-covered fibers can bind to each other if they are pressed together at sufficiently high temperature and pressure.
By taking advantage of hot pressing technology, the project aims to develop and improve the properties of bio-based 3D honeycomb-like materials (bee-cake-like structure) used in various panels in the construction industry. Such a board consists of several layers of paper: fluting (the corrugated structure), innerliner (the inner layer of paper that covers the fluting on the inside of a carton) and liner (referring to both the innerliner and outerliner on fluting and in corrugated cardboard).
Each of the paper components in the multi-layer board material is pre-treated with hot pressing technology without the addition of strength-enhancing chemicals, so that high strength and water resistance are obtained. The hot-pressed materials can then be joined together and converted into strong and water-resistant 3D honeycomb-like sheets and without the use of plastic coating.
In the current project, the end user of the material is a manufacturer in the flooring industry, but the goal is that the materials will be able to be used in several areas within building construction. Materials made from 100% forest raw materials are easy to recycle. Strong and water-resistant materials enable increased reuse with strengthened circularity. This also contributes to a significantly reduced carbon footprint.