Using ionic liquids to reduce energy consumption for carbon fibre production

Carbon fibre composites are lightweight, high performance materials with outstanding mechanical properties. However, the use of carbon fibre is limited to high-end applications largely due to their high manufacturing cost. A significant portion of the cost results from the energy input required to convert the precursor into carbon fibre. Stabilization is the first critical step whereby the fibre undergoes a series of thermal treatments creating a stabilized fibre ready for carbonization. In this study, we demonstrate the use of ionic liquids as polyacrylonitrile fibre impregnation agents, resulting in substantially lower fibre stabilization temperatures and thus significant energy savings. The use of infrared, calorimetric, and thermogravimetric studies indicated that the beneficial effect of ionic liquids is due to higher stabilization chemical reaction rates.