Abstracts Book - IMRC 2018

• SE2-P009
EFFECT OF CARBON NANOTUBE CONCENTRATION AND LENGTH
ON THE PIEZORESISTIVE RESPONSE OF MWCNT/PMMA
COMPOSITES UNDER AXIAL TENSION
Jesus Ramon Cob Cantu 1 , Andrés Iván Oliva Avilés 2 , Andres Ivan Oliva Arias 1 , Francis Avilés
Cetina 3
1 Centro de Investigación y de Estudios Avanzados del IPN - CINVESTAV, Applied Physics,
Mexico. 2 Universidad del Mayab S.C., División de Ingeniería y Ciencias Exactas, Mexico. 3 Centro
de Investigación Científica de Yucatán, Unidad de Materiales, Mexico.
The effective physical properties of carbon nanotube (CNT)/polymer composites
(e.g. electrical, thermal, piezoresistive) are highly dependent on the morphology
of the interconnected CNT network within the polymer. The constitution of such
a network is governed by parameters such as the CNT dispersion, orientation
and length, which are strongly influenced by the manufacturing process. In this
work, the combined effect of the concentration and length of multiwalled
carbon nanotubes (MWCNTs) on the electrical and piezoresistive (i.e. change of
electrical resistance under strain) properties of MWCNT/polymethyl
methacrylate (PMMA) composites were investigated. To fragment the MWCNTs,
a controlled methodology based on application of high ultrasonic energy in
solution was used, validating the reduction of the MWCNT length by statistical
analysis of CNT length measurements by scanning electron microscopy.
Electrical conductivity and percolation of the MWCNT/PMMA systems with
fragmented and non-fragmented MWCNTs are obtained, showing a reduction
of electrical conductivity and increased percolation threshold when the
MWCNTs are fragmented. The effect of the MWCNT concentration and length
on the electromechanical sensitivity (i.e. gage factor) of the MWCNT/PMMA
composites is also evaluated. The influence of aligning the MWCNTs by electric
fields on the electrical and piezoresistive properties of the composites will also
be explored.
Acknowledgment: This work was supported by the “Fondo Sectorial de
Investigación para la Educación” through the SEP-CONACYT grant No. 235905
(A. I. Oliva-Avilés). J. Cob thanks to CONACYT (Mexico) for the scholarship.
Keywords: carbon nanotubes, nanocomposites, piezoresistivity
Presenting authors email: ramon35_76@hotmail.com