rubber (CR), butyl rubber (copolymer of isobutylene and isoprene, IIR), halogenated butyl rubbers (chloro butyl rubber: CIIR; bromo butyl rubber: BIIR), styrenebutadiene rubber (copolymer of styrene and butadiene, SBR), nitrile rubber (copolymer of butadiene and acrylonitrile, NBR), etc. which can be cured by sulfur
vulcanization and, (2) saturated rubbers e.g. EPM (ethylene propylene rubber),
EPDM rubber (ethylene propylene diene rubber, a terpolymer of ethylene, propylene and a diene-component), epichlorohydrin rubber (ECO), polyacrylic rubber
(ACM), silicone rubber (SR), fluorosilicone rubber, ethylene-vinyl acetate
(EVA) etc.
3 One-Dimensional Fillers
Fillers are classified depending on their shapes and sizes which dramatically alter
the properties when mixed with the elastomeric matrix to prepare a composite.
When the size of the filler is reduced to nanometer dimension (at least one
dimension in the range of 1–100 nm) it is called nano-filler and depending on the
confinement of the filler’s coordinates it is classified into (1) zero dimensional, all
three coordinates are confined, (2) one-dimensional, confinement of any two coordinates, (3) two-dimensional, one coordinate is confined and, (4) three-dimensional,
no confinement of any dimension. Therefore, the one-dimensional filler is having
only one dimension (length) and other two dimensions are confined to few nanometers making these fillers with highest aspect ratio. Generally, three types of fillers
are well known for one-dimensional fillers e.g. nanotube, nanorod and nanofiber.
3.1 Nanotube
Amongst the nanotubes, CNT is widely used and is available with different
dimensions. Depending on the number of layers in the side wall it is categorized
as single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube
(MWCNT) and can have very large length up to few microns [30, 31]. There are
currently at least five methods for producing CNTs: (1) arc discharge [32], (2) chemical vapor deposition (CVD) [33], (3) laser ablation [34], (4) high pressure carbon
monoxide (HIPCO) [35], and (5) surface mediated growth of vertically-aligned
tubes by plasma enhanced chemical vapor deposition (PECVD) [36]. CNTs have
nanoscale dimension ranging from 1 to 100 nm in diameter and having a cylindrical
shape containing outstanding optical, thermal conductivity, mechanical and electrical properties with high aspect ratio, suitable for extensive nanodevices. It has
conjugated skeleton, appropriate for chemical reaction, making it unique for
functionalization through the covalent attachment of chemical groups, and thereby
alter the CNTs suitable for easy dispersion and/or soluble in liquids/polymer
matrices [37]. CNT derivatives result in ‘doping’ of a nanotube that changes its
Nonlinear Viscoelasticity of One Dimensional Filler Reinforced Elastomer. . .
17
vulcanization and, (2) saturated rubbers e.g. EPM (ethylene propylene rubber),
EPDM rubber (ethylene propylene diene rubber, a terpolymer of ethylene, propylene and a diene-component), epichlorohydrin rubber (ECO), polyacrylic rubber
(ACM), silicone rubber (SR), fluorosilicone rubber, ethylene-vinyl acetate
(EVA) etc.
3 One-Dimensional Fillers
Fillers are classified depending on their shapes and sizes which dramatically alter
the properties when mixed with the elastomeric matrix to prepare a composite.
When the size of the filler is reduced to nanometer dimension (at least one
dimension in the range of 1–100 nm) it is called nano-filler and depending on the
confinement of the filler’s coordinates it is classified into (1) zero dimensional, all
three coordinates are confined, (2) one-dimensional, confinement of any two coordinates, (3) two-dimensional, one coordinate is confined and, (4) three-dimensional,
no confinement of any dimension. Therefore, the one-dimensional filler is having
only one dimension (length) and other two dimensions are confined to few nanometers making these fillers with highest aspect ratio. Generally, three types of fillers
are well known for one-dimensional fillers e.g. nanotube, nanorod and nanofiber.
3.1 Nanotube
Amongst the nanotubes, CNT is widely used and is available with different
dimensions. Depending on the number of layers in the side wall it is categorized
as single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube
(MWCNT) and can have very large length up to few microns [30, 31]. There are
currently at least five methods for producing CNTs: (1) arc discharge [32], (2) chemical vapor deposition (CVD) [33], (3) laser ablation [34], (4) high pressure carbon
monoxide (HIPCO) [35], and (5) surface mediated growth of vertically-aligned
tubes by plasma enhanced chemical vapor deposition (PECVD) [36]. CNTs have
nanoscale dimension ranging from 1 to 100 nm in diameter and having a cylindrical
shape containing outstanding optical, thermal conductivity, mechanical and electrical properties with high aspect ratio, suitable for extensive nanodevices. It has
conjugated skeleton, appropriate for chemical reaction, making it unique for
functionalization through the covalent attachment of chemical groups, and thereby
alter the CNTs suitable for easy dispersion and/or soluble in liquids/polymer
matrices [37]. CNT derivatives result in ‘doping’ of a nanotube that changes its
Nonlinear Viscoelasticity of One Dimensional Filler Reinforced Elastomer. . .
17