Electrified jetting is a process to develop liquid jets having a nanometer-sized diameter, using electro-hydrodynamic forces. With an electric potential on a droplet of conducting liquid, the force balance between electric field and surface tension causes the development of a conical shape and above a critical point, a highly charged liquid jet is ejected from the apex of the cone. Both electrospraying and electrospinning processes have been used in this manner; the former results in a fragmented spray of droplets and the latter gives a way to develop very small-diameter fibers. Recently, electrospinning has witnessed increasing attention and nanofibers have been spun from a wide variety of polymers and using multi-component jetting systems. Anisotropic multi-phasic nano-objects possessing two distinct phases could establish significant advances in nanotechnology - the possibility of selective modification of each side of the biphasic object makes this system very attractive and versatile for electronic and biomedical applications.
Researchers at the University of Michigan have developed methods of fabricating polymer-based biodegradable multiphasic particles by electrified jetting. Their design jets two or more different liquids in side-by-side capillaries, thus generating a composite liquid stream with a multiphasic cone-jet. This formed cone-jet is then exposed to a force field, causing the composite liquid stream to at least partially solidify into a nano-object. Appropriate selection of jetting liquids and process parameters allows formation of a variety of biphasic nano-objects with morphologies such as nanofibers or nano-spheres. Additionally, surface modification with selective reactions further increases the number of potential products using this method. The biphasic objects include composite structures that are nanocrystals as well as structures with surfaces modified by selective reactions.
Applications and Advantages
- Design and manufacturing of multiphasic particles-nl-for a variety of biomedical applications.
- Also photonic, electronic, and storage devices
- Flexible production parameters to vary output