Matthew T. Hunley

Melt dispersion and electrospinning of non-functionalized multiwalled carbon nanotubes in thermoplastic polyurethane.

Nanoscale fibers with embedded, aligned, and percolated non-functionalized multiwalled carbon nanotubes (MWCNTs) were fabricated through electrospinning dispersions based on melt-compounded thermoplastic polyurethane/MWCNT nanocomposite, with up to 10 wt.-% MWCNTs. Transmission electron microscopy indicated that the nanotubes were highly oriented and percolated throughout the fibers, even at high MWCNT concentrations. The coupling of efficient melt compounding with electrospinning eliminated the need for intensive surface functionalization or sonication of the MWCNTs, and the high aspect ratio as well as the electrical and mechanical properties of the nanotubes were retained. This method provides a more efficient technique to generate one-dimensional nanofibers with aligned MWCNTs.

Submicron functional fibrous scaffolds based on electrospun phospholipids

Wormlike micelles of phospholipids were recently electrospun into ultraporous, high surface area fibrous membranes. These biologically-derived materials offer many potential applications, such as cell growth scaffolds, purification membranes, and drug-delivery platforms. Future work in tailoring the electrospinning process and phospholipid properties is expected to create new durable, biofunctional materials. These initial efforts have introduced the concept of low molar mass amphiphiles as precursors of biocompatible fibers through solution electrospinning.

Taking Advantage of Supramolecular Structure in Melt and Solution Electrospinning

Electrospinning, a polymer processing technique to create nanofibrous membranes, has been used to fabricate fibrous membranes from solution and melt phases showing supramolecular order. Wormlike micellar phases of low molar mass amphiphiles, including the phospholipid mixture asolectin, were electrospun under normal conditions to form micron-sized fibers. From the melt, well defined phospholipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine was electrospun into a similar fibrous membrane. Additionally, thermoreversible physical crosslinks were used to prepare fibers from low molecular weight, star-shaped poly(D,L-lactide) under melt electrospinning conditions.