Structure and properties of polyethylene nanofibers from molecular dynamics simulations

POLY 95

Sezen Curgul, sezen@mit.edu1, Krystyn J. Van Vliet1, and Gregory C. Rutledge2. (1) Department of Materials Science and Engineering, MIT, 77 Mass Ave, Cambridge, MA 02139, (2) Department of Chemical Engineering, MIT, 77 Mass Ave, Cambridge, MA 02139
Their combined characteristics of small fiber diameter (50-500 nm) and large surface area (10-100 m2/g) make polymeric nanofibers an exciting new class of materials that can be used in many applications. Here we report the results of molecular dynamics (MD) simulations of polymer nanofibers to study their structure and properties. The fibers mimic the prototypical polymer polyethylene and have diameters in the range 2.0 to 23.0 nm. The fibers are analyzed for signatures of emergent behavior in their structural and thermal properties as a function of diameter. The interfacial excess energy is shown to increase with decreasing fiber size for fibers below 5 nm in diameter. Glass transition temperatures (Tg) of the nanofibers are depressed as the fiber size decreases and there is no significant dependence of the Tg of nanofibers on the molecular weight.
 

General Papers: Polymers in Nanotechnology
1:00 PM-5:00 PM, Sunday, August 19, 2007 Westin Boston Waterfront -- Douglas, Oral

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007