Self-Crimping Bicomponent Nanofibers Electrospun from Polyacrylonitrile and Elastomeric Polyurethane

摘要

We have produced bicomponent nanofibers by side-by-side electrospinning of two different polymer solutions using a microfluidic device as the spinneret. By dissolving one of the polymer components from the nanofibers, the side-by-side bicomponent morphology can be clearly demonstrated. Using this technique, it is possible to prepare even smaller nanofibers by sacrificing one of the polymer components, or to create multicomponent nanofibers. Selectively functionalizing the two bicomponent sides can equip this bicomponent fiber with unique functions for special applications. For example, if one of the bicomponent sides is electrically conductive while the other is able to absorb chemicals selectively, the differential shrinkage triggered by the absorption of chemicals on one component side would make the fiber bend. This bending may then switch an electrical circuit on or off due to the mechanical bending of the conductive side. This nanofiber could be potentially used as a nanome-chanical chemical sensor, similar to micromechanical chemical sensors. Also, if the differential shrinkage of the two nanofibers could be triggered by an external stimulus, such as humidity, temperature, optical irradiation, electrical pulses, or chemicals, then these fibers could be used as nanotweezers or other forms of nanoactuators.