indicating the interactions among nanotubes or their transient physical gelation
level decreases under the large shear deformation [29]. The viscoelastic properties
of rubber nanocomposites also include the dynamic mechanical properties. The
dynamic mechanical properties of silicone rubber/carbon nanotube composites
have been reported by A. Katihabwa et al. The dynamic mechanical properties of
an unfilled rubber depend on temperature and frequency under a given strain. On
the other hand, the storage modulus decreases with increasing strain amplitude in
filled rubbers which is known as Payne effect. It is observed from Fig. 13 that the
Payne effect decreases with decreasing amount of CNTs and is not observable for
the nanocomposites containing CNTs less than 5 wt%. It can be concluded that
nanocomposites with more than 5 wt% CNTs gives percolating network. Moreover,
Fig. 12 The dynamic
storage modulus (G
0 ) for
PCT3 sample obtained at
various strain levels
(reproduced with
permission of John Wiley &
Sons, Inc., D. Wu et al.,
Journal of Polymer Science:
Part B: Polymer Physics
[29])
Fig. 13 Dynamical
mechanical properties of
uncured CNT/SiR used
RPA (reproduced with
permission of A. Katihabwa
et al., Journal of Reinforced
Plastics and Composites
[30])
146
S. Nayak and T.K. Chaki