Zhao et al. [32] carried out a surface modification of TiO 2 nanoparticles with the
silane coupling agents; 3-aminopropyl trimethoxysilane (APTMS) and
3-Isocyanato propyl trimethoxysilane (IPTMS). The process of nanoparticle surface modification by silane coupling agents is shown in Fig. 2. Various anionic
surfactants have been used to disperse nano TiO 2 [33].
2.2 Tubular (One Dimensional, 1D) Nanofillers
2.2.1 Carbon Nanotubes
There are two basic types of carbon nanotubes (CNT) viz. single walled carbon
nanotubes (SWCNT) and multi walled carbon nanotubes (MWCNT) [34]. A special
case of MWCNT called double walled carbon nanotubes (DWCNT) contains two
concentric graphene cylinders. Figure 3 represents the rolling of graphene sheets to
form SWCNT, DWCNT and MWCNT. CNT can be synthesised by arc-discharge
[35], laser ablation [36], or catalytic chemical vapour deposition (CCVD) [37]
methods. CNTs have a planar hexagonal arrangement of sp
2 bonded carbon
atoms, with each carbon atom joined to three neighbours, as in graphite [38].
Fig. 2 Chemical grafting
of organosilanes onto TiO 2
nanoparticles surface [32]
Non-linear Viscoelastic Behaviour of Rubber-Rubber Blend Composites and. . .
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