Chemical and Morphological Modification of PAN Nanofibrous Mats with Addition of Casein after Electrospinning, Stabilisation and Carbonisation

Electrospun polyacrylonitrile (PAN) nanofi brous mats belong to typical precursor materials of carbon nanofibres. They have, however, the problem that they need to be fixed or even stretched during stabilisation and ideally also during carbonisation in order to avoid undesired conglutinations and deformations of the original nanofibre morphology, resulting in brittle behaviour of the macroscopic nanofibrous mat, which impedes several applications. In an earlier investigation, blending PAN with ZnO was shown to increase fibre diameters and lead to unproblematic stabilisation and carbonisation of nanofibrous mats. ZnO, on the other hand, may have a negative impact on biotechnological applications such as tissue engineering. Here, we thus report on the morphological and chemical modifi cations due to blending PAN electrospinning solutions with different amounts of casein. By optimising the PAN : casein ratio, relatively thick, straight nanofibres are obtained, which can be stabilised and carbonised unambiguously, without the well-known negative impact on cell adhesion due to the addition of ZnO.