Effect of acid modification on electrical properties of carbon nanotube/epoxy resin composites

Carboxyl-functionalized multi-walled carbon nanotube(C-MWCNT) was prepared by mixed acid method using original carbon nanotube(R-MWCNT). Two types of multi-walled carbon nanotube/epoxy resin nanocomposites were prepared respectively. Infrared spectrum and scanning electron microscope revels that this method cuts off carbon nanotubes effectively and grafts small amount of hydroxyl and carboxyl groups on the surface. Test shows that the volume resistivity of C-MWCNT/EP is 8 to 11 magnitudes higher than that of R-MWCNT/EP. Percolation threshold of R-MWCNT/EP is about 0.03wt.% while C-MWCNT/EP does not show percolation within test filler content. J-E curves of R-MWCNT/EP shows strong nonlinear behavior which matches the characteristic of field emission while no obvious relation is found in the case of C-MWCNT/EP. Dielectric spectrum shows the addition of C-MWCNT does not change the polarization mechanism of epoxy resin while R-MWCNT/EP shows a complete different dielectric spectrum pattern. The changes on dielectric behavior and electrical conductivity are due to the change of CNT structure and CNT-EP interface, which is mainly caused by acid modification.

[1]  Feipeng Du,et al.  Thermal Conductivity of Epoxy Resin Reinforced with Magnesium Oxide Coated Multiwalled Carbon Nanotubes , 2013 .

[2]  T. Vo,et al.  Effect of carbon nanotube lengths on the mechanical properties of epoxy resin: An experimental study , 2013 .

[3]  Karl Schulte,et al.  Hydrothermally resistant thermally reduced graphene oxide and multi-wall carbon nanotube based epoxy nanocomposites , 2013 .

[4]  Eugene M. Terentjev,et al.  Dispersion of Carbon Nanotubes: Mixing, Sonication, Stabilization, and Composite Properties , 2012 .

[5]  Shengtao Li,et al.  A new potential barrier model in epoxy resin nanodielectrics , 2011, IEEE Transactions on Dielectrics and Electrical Insulation.

[6]  Arash Montazeri,et al.  Viscoelastic and mechanical properties of multi walled carbon nanotube/epoxy composites with different nanotube content , 2011 .

[7]  Yiu-Wing Mai,et al.  Improving thermal conductivity while retaining high electrical resistivity of epoxy composites by incorporating silica-coated multi-walled carbon nanotubes , 2011 .

[8]  Y. Mai,et al.  Physical properties and applications of polymer nanocomposites , 2010 .

[9]  B. Keskinler,et al.  An amperometric biosensor based on multiwalled carbon nanotube-poly(pyrrole)-horseradish peroxidase nanobiocomposite film for determination of phenol derivatives. , 2008, Talanta.

[10]  K. Wolter,et al.  Investigations of carbon nanotubes epoxy composites for electronics packaging , 2008, 2008 58th Electronic Components and Technology Conference.

[11]  W. Bauhofer,et al.  A review and analysis of electrical percolation in carbon nanotube polymer composites , 2009 .

[12]  Y. Ohki,et al.  Proposal of a multi-core model for polymer nanocomposite dielectrics , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[13]  Safa Kasap,et al.  Principles of electronic materials and devices , 2000 .

[14]  Milo S. P. Shaffer,et al.  Development of a dispersion process for carbon nanotubes in an epoxy matrix and the resulting electrical properties , 1999 .

[15]  Isaac Balberg,et al.  Percolation thresholds in the three-dimensional sticks system , 1984 .