Carbon fibre production using an ecofriendly water-soluble precursor

Carbon fibre (CF) is a lightweight next-generation material with numerous applications. CF production is predominantly based on the polyacrylonitrile (PAN) precursor because of the high tensile strength of PAN-based CFs (PAN-CFs). However, expensive and toxic organic solvents are required for PAN-CF production. Moreover, the corresponding thermal stabilisation process is highly energy-intensive, leading to high CO₂ emissions. Herein, aqueous polyacrylamide (aqPAM) fibre-prepared via polymerisation and dry spinning using water-is proposed as a water-soluble CF precursor that can be converted into high-performance CF at high carbon yields. The incorporation of small amounts of phosphoric acid into aqPAM considerably reduces the thermal stabilisation time and increases the carbon yield compared with that obtainable using PAN-CF. Moreover, the carbonised aqPAM-based CFs exhibit a high tensile strength and tensile modulus comparable with those of PAN-CFs. The developed process generates less CO₂ emissions than PAN-CF production.