A comparative study on long and short carbon nanotubes-incorporated Polydimethylsiloxane nanocomposites

In order to analyze the different aspect ratio carbon nanotubes on the mechanical, electrical and thermal properties of the Polydimethylsiloxane (PDMS), long multiwalled carbon Nanotubes (LC), short multiwalled carbon nanotubes (SC) were incorporated into PDMS by solution blending method, respectively. Filling 2.0 wt.% of LC, the volume resistance (Rv) and surface resistance (Rs) were dereased 2, 3 orders of magnitude as compared with LC-PDMS-01. When the LC was increased to 3 wt.%, Rs and Rv dereased beyond the lower measurement range.The modulus of the SC/PDMS and LC/PDMS composites gradually increased with the filler content increased, while the elongation at break of the SC/PDMS and LC/PDMS composites decreased with the filler content increased. The LC-PDMS-02 also shows the excellent mechanical properties with the higher modulus of 2.84 MPa and elongation at break of 157.85% than those of SC-PDMS-02. Both LC and SC could enhance the thermal stability of PDMS. Furthermore, in the range of 530ºC to 600ºC, the thermal stability of PDMS with LC is more stable than that of PDMS with SC. In this case, LC is more advantageous than SC due to its greater aspect ratio. Thus, LC with high aspect ratio has the potential of being reinforcing filler than SC.