Mechanical and Material Characterization
of Polymeric Nanofibers
Mechanical characterization requires deposition of aligned individual fibers with appropriate boundary conditions. Individual manipulation and subsequent achievement of desired boundary conditions of sub-100 nm diameter fibers is virtually impossible as they are prone to damage. In this regard, an integrated approach was pioneered, which, without external manipulation enables deposition of aligned fibers in known locations with fixed-fixed boundary conditions. The integrated approach comprises of depositing fibers on Transmission Electron Microscopy (TEM) grids, which are mapped for exact fiber location using the TEM. The mapped grids are then accurately positioned under the Atomic Force Microscope (AFM) and mechanically characterized using lateral force microscopy (LFM). The broken fibers are then measured for accurate fiber dimensions using Scanning Electron Microscope (SEM). The integrated approach has successfully demonstrated the ability to mechanically characterize polymeric fibers with diameters ranging from 30 nm to sub-micrometers. The distinctive feature of this approach lies in the ability to characterize a large number of fiber samples of different polymers having a wide range of diameters with fixed-fixed boundary conditions.
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AFM voltage data and SEM images of polymeric fiber fractured and plastically deformed demonstrating the establishment of fixed-fixed boundary conditions ("Use of images is only allowed with prior permission" ). |
Publications under Preparation:
A. S. Nain, T. Kowalewski, M.
Sitti and C. Amon, “Integrated approach for polymeric micro/nanofiber
mechanical characterization”, to be submitted to ACS Nano.
A. S. Nain,
A. S. Nain, B. Sumer, C. Onal, M. Sitti and C. Amon, “Lateral Force Microscopy of Poly(methyl methacyrlate) micro/nanofibers using AFM”, to be submitted to Nano Letters.