Title: Biobased Carbon Fibres: Investigation of the Carbonisation Step of Lignin-Cellulose Precursors
The exceptional mechanical properties and low density of carbon fibres make them highly attractive as the load-bearing component in lightweight applications, such as wind turbine blades. The production of commercial carbon fibres involves spinning of a precursor fibre (PF) which is thermally converted into carbon fibres by oxidative stabilisation (200-350 °C) followed by carbonisation (>1000 °C) in inert atmosphere. The majority (~96%) of commercial carbon fibres are produced from the petroleum-based polymer polyacrylonitrile (PAN).
The high costs of PAN as well as the energy intensive thermal treatments is reflected in the price of carbon fibres, and is the main reason why carbon fibre composites are still restricted to high-end applications. Lignin and cellulose are interesting renewables for the replacement of PAN in carbon fibre production. The prime motivation of using lignin is its high carbon content while cellulose has a desirable molecular order.