interfaces [3–12]. Reinforcement with one dimensional fillers like nanotubes,
nanorods and nanofibers have the largest surface area per unit volume and plays
the crucial role to increase the strength, abrasion resistance, cracking resistance,
thermal, gas barrier, structural properties, conductivity and viscoelasticity by
increasing the interfacial area [13–17]. This outstanding advantage of properties
improvement is due to the filler network and interactions between elastomer and
filler. Most of the one dimensional filler based composites of modern era have been
focused on the percolation thresholds, minimum loading of the filler to achieve
significant improvement of the properties of the matrix phase [18]. However,
several thermoplastic elastomers behave differently because of their nonlinear
responses induced by various factors such as high deformation and stress softening
effect, but, it is important from the application point of view that it combines the
characteristics of both rubber and plastic for typical engineering material [19]. Rubber composites reinforced with different fibers are extensively used in many
industrial products in automobiles, seal components, screen nets and tyre treads
[20, 21]. Carbon based nanofillers like carbon nanotube (CNT), carbon nanofiber
(CNF) and carbon nanorods are important class of reinforcing material amongst one
dimensional fillers to make a composite with rubber/elastomers due to the high
aspect ratio and other outstanding physical properties [22, 23]. The properties of the
filled composites mainly depend on the shape, size and concentration of the filler
along with its chemical functionalization [24, 25]. However, nanotechnology has
been implemented using nanofillers to make composites of elastomers for last two
decades [26–28]. For elastomeric composites, the curing reactions play a multifaceted role due to occurrence of many reactive processes simultaneously [29]. Viscoelasticity is an important property of polymeric materials that demonstrates both
viscous and elastic character when undergoes deformation. Viscous materials
favours shear flow and strain linearly with time when a stress is applied. Elastic
materials strain under stress and quickly return to its original state once the stress is
removed. Viscoelastic materials combine both elastic and viscous component
together making this class of materials unique. Further, when fillers are added to
elastomers, is properties alter dramatically especially in presence of nanometer
dimension fillers.
2 Different Elastomers
An elastomer is a viscoelastic polymer having low Young’s modulus and high
elongation at break. Elastomers are amorphous in nature and exist above their glass
transition temperature, so that considerable segmental motion is possible. Generally, two types of rubbers have been classified based on their origin; natural and
synthetic rubbers and the synthetic rubbers are derived mostly from petroleum
byproducts. Elastomers are also categorized structurally into two types (1) unsaturated rubber e.g. cis-1,4-polyisoprene; natural rubber (NR) and trans-1,4-polyisoprene gutta-percha, synthetic polyisoprene, polybutadiene (BR), chloroprene
16
K.K. Jana et al.
nanorods and nanofibers have the largest surface area per unit volume and plays
the crucial role to increase the strength, abrasion resistance, cracking resistance,
thermal, gas barrier, structural properties, conductivity and viscoelasticity by
increasing the interfacial area [13–17]. This outstanding advantage of properties
improvement is due to the filler network and interactions between elastomer and
filler. Most of the one dimensional filler based composites of modern era have been
focused on the percolation thresholds, minimum loading of the filler to achieve
significant improvement of the properties of the matrix phase [18]. However,
several thermoplastic elastomers behave differently because of their nonlinear
responses induced by various factors such as high deformation and stress softening
effect, but, it is important from the application point of view that it combines the
characteristics of both rubber and plastic for typical engineering material [19]. Rubber composites reinforced with different fibers are extensively used in many
industrial products in automobiles, seal components, screen nets and tyre treads
[20, 21]. Carbon based nanofillers like carbon nanotube (CNT), carbon nanofiber
(CNF) and carbon nanorods are important class of reinforcing material amongst one
dimensional fillers to make a composite with rubber/elastomers due to the high
aspect ratio and other outstanding physical properties [22, 23]. The properties of the
filled composites mainly depend on the shape, size and concentration of the filler
along with its chemical functionalization [24, 25]. However, nanotechnology has
been implemented using nanofillers to make composites of elastomers for last two
decades [26–28]. For elastomeric composites, the curing reactions play a multifaceted role due to occurrence of many reactive processes simultaneously [29]. Viscoelasticity is an important property of polymeric materials that demonstrates both
viscous and elastic character when undergoes deformation. Viscous materials
favours shear flow and strain linearly with time when a stress is applied. Elastic
materials strain under stress and quickly return to its original state once the stress is
removed. Viscoelastic materials combine both elastic and viscous component
together making this class of materials unique. Further, when fillers are added to
elastomers, is properties alter dramatically especially in presence of nanometer
dimension fillers.
2 Different Elastomers
An elastomer is a viscoelastic polymer having low Young’s modulus and high
elongation at break. Elastomers are amorphous in nature and exist above their glass
transition temperature, so that considerable segmental motion is possible. Generally, two types of rubbers have been classified based on their origin; natural and
synthetic rubbers and the synthetic rubbers are derived mostly from petroleum
byproducts. Elastomers are also categorized structurally into two types (1) unsaturated rubber e.g. cis-1,4-polyisoprene; natural rubber (NR) and trans-1,4-polyisoprene gutta-percha, synthetic polyisoprene, polybutadiene (BR), chloroprene
16
K.K. Jana et al.