Electrospun BPO co-polyimide nanofibers can be stiff and strong while at the same time exhibiting moderate ductility.

A novel and efficient way to evaluate mechanical properties of aligned nanofiber bundles (∼30 nanofibers in a bundle) by virtue of a micro-tensile tester was reported.

Evaluation of the bundle data using Daniel's theory based on Weibull statistics resulted in a predicted tensile strength of about 1.9 GPa for single nanofibers.