Jerome Lynch & Nicholas Kotov Univ Michigan, Ann Arbor
This project seeks to further miniaturize the sizes and reduce the costs of structural sensors while simultaneously increasing performance. Strain and corrosion sensors are designed using a new nano-composite comprised of single wall carbon nanotubes (SWNT) and polyelectrolyte (PE) molecules. The natural piezoresistive properties of SWNT-polyelectrolyte thin films render them ideal for strain sensing. SWNT-PE strain sensors would be characterized by excellent linearity and long-term stability as compared to traditional metal foil gauges. This project will also explore the use of SWNT-PE thin films for corrosion sensing. With the surfaces of SWNT and polyelectrolyte molecules chemically modified to provide reactive surfaces, the binding of chloride ions and other corrosive elements will induce changes in the film bulk conductivity. Such thin films would offer reliable measures of the concentration of corrosive elements within cementitious structural elements. The thin film sensors will be patterned as inductive elements that can be read wirelessly through electromagnetic coupling. This work stands to have far reaching broad impacts including: rapid transfer of sensor technology into industrial practice, integration of research findings with current curricula, and recruitment of underrepresented students through interaction with the Women in Science and Engineering (WISE) and the Detroit Area Pre-College Engineering Program (DAPCEP) programs.
This is a project supported under FY05 Sensors Initiative NSF 05-526.