Single-walled carbon nanotubes (SWNTs) and SiC nanoparticles were dispersed in natural rubber (NR) polymer
solution and subsequently evaporated the solvent to prepare NR nanocomposites. Using this technique, nanoparticles
can be better dispersed in the NR matrix. The influence of nano-fillers on the mechanical properties of the resulting
nanocomposites was quantified.
Mechanical test results show an increase in the initial modulus with nanoscale reinforcements for up to 50% strain
compared to pure NR. The modulus and strength of natural rubber with 1.5% SiC nanoparticles appear to be superior
to those of SWNTs with the same filler content. In addition to mechanical testing, these nanocomposites were studied
using the SEM and Raman spectroscopy techniques in order to understand the morphology of the resulting system and
the load transfer mechanism, respectively. The Raman spectrum of the SWNT/NR system is characterized by a strong
band at 1595 cm1 (G mode—C–C stretching) and other two bands at 1300 cm1 (D mode-disorder induced) and
2590 cm1 (D* band). A shift of the 2590 cm1 Raman band to the lower wavenumber was observed after subjecting
SWNT/NR sample to cyclic stress testing. Ageing SWNT/NR specimen in distilled water for 30 days also provided a
similar result. The Raman shift in aged samples indicates internal stress transfer from the natural rubber matrix to the
SWNTs implying the existence of bonding at the interface.