AVS 52nd International Symposium
    Nanometer-Scale Science and Technology Tuesday Sessions
       Session NS-TuP

Paper NS-TuP11
Carbon Nanotube Copolypeptide Bionanocomposites

Tuesday, November 1, 2005, 4:00 pm, Room Exhibit Hall C&D

Session: Nanometer Scale Science and Technology Poster Session
Presenter: C. Lovell, University of Virginia
Authors: C. Lovell, University of Virginia
E. Worthington, University of California, Santa Barbara
T.J. Deming, University of California, Los Angeles
G.D. Stucky, University of California, Santa Barbara
J. Kang, National Institute of Aerospace
K.E. Wise, National Institute of Aerospace
J.S. Harrison, NASA Langley Research Center
J.M. Fitz-Gerald, University of Virginia
C. Park, National Institute of Aerospace
Correspondent: Click to Email
Due to their helical structures, several biopolymers exhibit high shear piezoelectricity. Unfortunately, few natural biopolymers exhibit adequate physical properties to endure practical utilization of their sensing capabilities. Thus, this investigation seeks to explore the shear sensing potential of a synthetic biopolymer. By combining peptides and polymers, synthetic polypeptides should bridge the gap between expensive, functional peptides and inexpensive, less functional polymers. Further augmentation of their electroactive potential and mechanical properties can be achieved by addition of carbon nanotubes (CNTs) to form a nanocomposite material with very low density . Functional characterization of drop-casted thin films was performed, including electrical and dielectric measurements, as well as mechanical tests. It was found that several properties, including conductivity, permittivity, tensile strength, Young's modulus, and toughness increased with SWNT loadings. However, one of the main limiting factors in achieving the best performance of CNT-polymer composites is a sharp increase of material viscosity at high concentrations (5-6 wt.%) of CNTs, which limits the capabilities of conventional fabrication techniques. In order to exploit the unique properties of CNTs in macroscopic composites, significant progress has to be made in the development of new advanced fabrication and processing methods, allowing control over spatial distribution and alignment of CNTs in the matrix. For this reason, a novel process termed "matrix assisted pulsed laser evaporation" (MAPLE) was used in creating several CNT-copolypeptide nanocomposites. These results, as well as the preliminary investigation of the copolypeptide's shear piezoelectric properties, will be presented. @FootnoteText@ @footnote 1@ S. B. Sinnott and R. Andrews, Carbon nanotubes: synthesis, properties, and applications, Crit. Rev. Sol. State Mat. Sci. 26, 145, 2001.