Polyisoprene single-wall carbon nanotube composites synthesized under high pressure

Abstract

The mechanical and thermal properties of high-pressure-synthesized composites of polyisoprene (PI) and single-walled carbon nanotubes (SWCNTs) (1 wt%) have been measured using a tensile tester and the transient hot-wire method. PI–SWCNT composites were prepared by ultrasonic mixing in toluene to obtain good dispersion of the nanotubes within the polymer matrix, which was verified by atomic force microscopy. The mixtures were dried for several days under dynamic vacuum and subsequently treated at a high pressure (∼0.5 GPa) and temperature (513 K) to improve the SWCNT–polymer interaction. As a result of the high-pressure treatment, PI becomes crosslinked, yielding an elastomeric PI–SWCNT composite. Preliminary results show that the tensile strength and Young's modulus of the composite are 2.8 and five times higher, respectively, than those of pure high-pressure-treated PI, and that the thermal conductivity increased ∼30% by adding 1 wt% SWCNTs.

Keywords:

• polyisoprene
• nanotubes
• tensile strength
• thermal conductivity
• composite

Acknowledgements

This work was financially supported by SIDA/SAREC of Sweden and the Swedish Research Council.