Deformation of isolated single-wall carbon nanotubes in electrospun polymernanofibres

Abstract

Electrospinning has been used to prepare poly(vinyl alcohol) (PVA) nanofibres, with diameters rangingfrom 1 µm down to 20 nm, that contain dispersions of isolated, well-aligned, single-wall carbon nanotubes(SWNTs). The nanofibres were characterized by electron microscopy and Ramanspectroscopy. Single Raman radial breathing modes (RBMs) were found for the SWNTs inthe nanofibres which allowed the identification of particular nanotubes and indicateddebundling/separation of the original SWNT ropes. Moreover the results of polarized Ramanspectroscopy were consistent with the presence of isolated SWNTs, well-aligned along thenanofibre axes. The nanofibres were subjected to deformation and the position of the G andG′ bands was followed as a function of strain. It was found that large band shifts were obtained, indicatingthat there was good stress transfer from the PVA matrix to the nanotubes. A band shift of up to40 cm−1 for 1% strainwas found for the G′ band which is similar to that reported for the deformation of isolated nanotubes. Thisindicates that the Young’s modulus of SWNTs is in excess of 800 GPa.