Piezoresistivity and Self-Sensing of Damage in MWCNT-Polymer Composites
January 24, 2011
- Dr. Francis Aviles Cetina
- Centro de Investigacion Cientifica de Yucatan (CICY)
- Holden Auditorium
- 4:00 p.m.
This talk will discuss the use of multiwalled (MW) carbon nanotubes (CNTs) as elements for sensing strain and matrix damage in MWCNT-polymer composites. Experimental results will be discussed to demonstrate the high sensitivity to strain and damage of a percolating CNT network, once this has been formed inside the polymer matrix. Specific results of two material systems will be discussed, one that employs a thermoplastic matrix in thin film geometry, and a second one which employs a bulk thermosetting matrix. In addition, this talk will discuss the influence of multi-walled carbon nanotube (MWCNT) alignment into a polymer matrix on the electrical and piezoresistive properties of the resulting composites. An alternating current electric field is employed for MWCNT alignment, which is macroscopically evident in the crystallized polymer. Electrical conductivity and electromechanical sensitivity were improved in the direction of the aligned network. CNT/polymer composites were also tested under loading-unloading cycles, presenting good strain-sensing capabilities.