FIELD OF THE INVENTION
The present invention relates to a functionally graded polymers (FGPs) and
functionally graded polymer nanocomposites (FGPNCs) having a gradation of
crosslinking density and a method for preparation of the same. This graded
materials having a variation of chemical crosslinking density that graded the
performance of materials in the target applications.
BACKGROUND OF THE INVENTION
In ceramic and metal based functional graded materials, many processing
methods are known like thermal spraying, powder metallurgy, coating
process, melt processing, etc with certain disadvantages of each technique
[B. Kieback, A. Neubrand and H. Riedel, "Processing techniques for
functionally graded materials", Materials Science and Engineering, A362,
(2003) pp 81-105]. In polymers, compositional and microstructural
gradients are intended to allow an optimum combination of component
properties, like surface hardness, wear resistance, impact resistance and
toughness. Graded polymers that have been processed so far include graded
porosity in polyurethane [H. Piechota, H. Rohr, Integralschaumstoffe,
Manser, Wien, 1975], graded fiber composites [Q. Wang, Z. Huang and S.
Ramakrishna, in K. Trumble, K. Bowman, I. Reimanis, and S. Sampath
(Eds), Functionally graded materials 2000, Proceedings of the 6*
International Symposium on Functionally Graded Materials 2000, Ceramic
Transactions. 114, American Ceramic Society, Westerville, OH, 2001, pp 89-
96], graded interpenetrating polymer networks [Y.S. Lipatov and L.V.
Karabanova, J. Materials Science, 30, (1995) pp 2475-2484], graded
biodegradable polyesters [C. Schiller, M. Siedler, F. Peters and M. Epple,
Functionally graded materials 2000, Ceramic Transactions 114, American
Ceramic Society, Westerville, OH, 2001, pp 97-107], graded index polymer
fibers and microlenses [S. Sato, T. Nose, S. Masuda, S. Yanase, in W.A.
Kaysser (Ed.), Functionally graded materials 1998, Proceedings of the 5*
International Symposium on Functionally Graded Materials 1998, Trans
Tech Publications, Switzerland, (1999), pp 567-572], polymer alloys [Y.
Kano, K. Ishikura, S. Kawahara and S. Akiyama, "Analysis of surface
segregation in blends of acrylate copolymer with fluoro copolymer", Polymer
Journal, (1992), 24(2), 135-144.], graded crystalline phase on the properties
of semicrystalline polymers [Y. Agari, "Development of functionally graded
polymer materials", Kagaku Kogyo (1999), 50(8), 630-639] and graded SiC
reinforcement in polymer matrix using centrifuging prior to polymerization
[N.J. Lee, J. Jang, M. Park, C.R. Choe, J. Materials Science, 32 (1997) pp
2013-2020]. '
On the other hand, polymeric materials in the industrial field are composites
comprising of three dimensional network structures and fillers. However,
studies on graded polymers prepared by solid polymer matrix are not done
or not known. Again one of the major drawbacks associated with
experimental studies is the preparation of FGMs having large scale
gradation and also availability of matrix materials in solid form.
PROBLEM DEFINITION;
Functionally Gradient Materials (FGMs) are nonhornogeneous materials in
which the material composition is varied spatially to optimize the
performance of the material for a specific application. With this concept,
research into the various aspects of FGMs such as processing, material
behavior under different types of loading, fracture mechanics etc., have
gained considerable attention and are still being pursued.
The chemical crosslinking density plays a major role to evaluate the
performance of material through mechanical properties. All mechanical
properties are related to the chemical crosslinking density as shown in Fig.
2. However, 'not a single patent/paper is available related to functionally
graded material where chemical crosslinking density varies from one surface
to the opposite surface. The present invention discloses a novel graded FGM
containing polymer matrix and other ingredients as chemicals like curing
agent(s), accelerator(s), antioxidants), etc, and a simple and inexpensive
process to prepare the same.
DISADVANTAGES OF THE EXISTING FGMS;
(1) From the application point of view conventional polymers and its
composite is suitable for a narrow range of temperature.
(2) Uniform gradation, both in increasing and decreasing order from inner
surface to outer surface and from outer surface to inner surface, and
also in radial direction are not possible.
(3) Large scale gradation is not possible in the existing FGMs.
(4) It is not possible to prepare polymeric FGM where the matrix material
is available at solid form at room temperature, 25°C.
Conventional polymer and its composite have a constant crosslinking
density. Conventional polymeric FGMs are prepared from polymer, which
are available in liquid form. The gradation is carried out by fiber or particles.
Therefore, it is difficult to produce a large-scale gradation. In addition to this
it is not possible to produce FGMs in radial direction.
OBJECTS OF THE INVENTION
An object of the present invention is to provide a functionally graded
polymers (FGPs) and functionally graded polymer nanocomposites (FGPNCs)
having a gradation of crosslinking density and a method for preparation of
the same, in which crosslinking density varies with distance.
Another object of the present invention is to provide a functionally graded
polymers (FGPs) and functionally graded polymer nanocomposites (FGPNCs)
having a gradation of crosslinking density and a method for preparation of
the same, wh.ich overcomes disadvantage(s) of prior art(s).
Further object of the present invention is to provide a functionally graded
polymers (FGPs) and functionally graded polymer nanocomposites (FGPNCs)
having a gradation of crosslinking density and a method for preparation of
the same, in which the surface, which has a low crosslinking density is
suitable for dynamic application, whereas the surface having high
crosslinking density is suitable for load bearing application. As a result
the same material can be used for a wider range of application.
SUMMARY OF THE INVENTION
In the present invention functionally graded polymeric materials (FGPs)
and functionally graded polymeric nanocomposites (FGPNCs) have been
developed.
In another embodiment of the present invention, a process has been
developed to fabricate functionally graded polymer composites and
functionally graded polymeric nanocomposites having various shapes (Fig 1)
and gradation using polymer matrix(s), nanosized filler(s), antioxidant(s),
accelerator(sj, accelerator activator(s), processing oil(s) and curing agent(s).
In another embodiment of the present invention, various curing agents i.e.,
sulphur, hydrogen peroxide, dicumyl peroxide, benzoyl peroxide,
diurethane, p-quinone dioxime, p-quinone dioxime dibenzoate, phenolformaldehyde
resin, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy)
hexane, bis(2,4-dichloro-benzoyl) peroxide, zinc oxide, amine, tertiary butyl
perbenzoate, magnesium oxide, zinc oxide, lead oxide, iron oxide, titanium
oxide, amine, phenol, sulfenamide, thiazoles, thiuram, thiourea, guanidine,
1,4-butanediol, 1,4-cyclohexanedimethanol, 1,4-bis(2-hydroxyethoxy)
benzene, 4,4'methylene-bis(2-chloroaniline), and mixture thereof etc are
used to make a novel functionally graded materials. Here the concentration
of curing agents varies from one surface to the opposite surface.
Fig. 1: Schematic diagrams of functionally graded polymers
(FGPs) and functionally graded polymer nanocomposites
(FGPNCs), where concentration varies from one surface to the
opposite surface.
In another embodiment of the present invention, various accelerators i.e.,
tert-buttylbenzthiazyl sulphonamide, benzthiazyl 2-sulphenmorpholide,
dicyclohexyl benzthiazyl sulphonamide, N-cyclohexyl-2-benzothiazole
sulfenamide, 2-mercaptobenzothiazole, 2,2'dibenzothiazyl disulfide,
tetramethylthiuram disulfide, zinc dimethyldithiocarbamate, zinc
dibutyldithiocarbamate, 4,4'dithiodimorpholine, tellurium
diethyldithiocarbamate, dipentamethylene thiuramhexasulfide,
tetramethylthiuram monosulfide, ferricdimethyldithiocarbamate, zinc
mercaptobenzthiazole, zinc 0,0 dibutylphosphorodithioate, zinc
diethyldithiocarbamate, 4-4'dithio dimorpholine, and mixture thereof etc are
used to make a novel functionally graded materials. Here the concentration
of accelerators varies from one surface to the opposite surface.
In another embodiment of the present invention, various processing
oils i.e., paraffinic oil, naphthenic oil, aromatic oil, vegetable oil, and
mixture etc are used to make a novel functionally graded materials. Here the
concentration of oil is same throughout the matrix.
In another embodiment of the present invention, various carbon
nanoparticles (act as reinforcing materials) i.e., N-110, N-115, N-120, N-121,
N-125, N-134, N-135, N-212, N-220, N-231, N-234, N-293, N-299, N-315, N-
326, N-330, N-335, N-339, N-343, N-347, N-351, N-356, N-358, N-375, N-
539, N-550, N-582, N-630, N-642, N-650, N-660, N-683, N-754, N-762, N-
765, N-772, N-774, N-787, N-907, N-908, N-990, N-991, etc are used to
make a novel functionally graded polymer nanocomposites. Here the
concentration of nanoparticles decreases or increases according to the
requirement, but the particle size remains constant in each FGPNCs.
In another embodiment of the present invention, various carbon
nanoparticles i.e., N-110, N-115, N-120, N-121, N-125, N-134, N-135, N-
212, N-220, N-231, N-234, N-293, N-299, N-315, N-326, N-330, N-335, N-
339, N-343, ft-347, N-351, N-356, N-358, N-375, N-539, N-550, N-582, N-
630, N-642, N-650, N-660, N-683, N-754, N-762, N-765, N-772, N-774, N-
787, N-907, N-908, N-990, N-991, etc are also used to make FGPNCs. Here,
the total volume fraction of carbon nanoparticles in FGPNCs is constant but
the particle size of nanoparticles decreases or increases from one surface to
the opposite surface.
In another embodiment of the present invention, various mixed carbon
nanoparticles i.e., combination of any two or more following carbons, i.e., N-
110, N-115, N-120, N-121, N-125, N-134, N-135, N-212, N-220, N-231, N-
234, N-293, N-299, N-315, N-326, N-330, N-335, N-339, N-343, N-347, N-
351, N-356, N-358, N-375, N-539, N-550, N-582, N-630, N-642, N-650, N-
660, N-683, N-754, N-762, N-765, N-772, N-774, N-787, N-907, N-908, N-
990, N-991, etc are also used to make FGPNCs. Here, both concentration
and particle size of nanoparticles decreases or increases at a time.
In another- embodiment of the present invention, various silica
nanoparticles i.e., precipitated silica (i.e., HS-200, HS-500, HS-700, etc) and
fumed silica are used to make a novel FGPNCs.
In another embodiment of the present invention, nanoclay is used to make
a novel FGPNCs.
In another embodiment of the present invention, various mixed
nanoparticles i.e., combination of any one of the following carbons, i.e., N-
110, N-115, N-120, N-121, N-125, N-134, N-135, N-212, N-220, N-231, N-
234, N-293, N-299, N-315, N-326, N-330, N-335, N-339, N-343, N-347, N-
351, N-356, N-358, N-375, N-539, N-550, N-582, N-630, N-642, N-650, N-
660, N-683, N-754, N-762, N-765, N-772, N-774, N-787, N-907, N-908, N-
990, N-991, etc, and silica (precipitated and fumed) or clay are also used to
make FGPNCs.
In another embodiment of the present invention, various polymer
matrixes i.e., natural rubber, styrene-butadiene rubber, polybutadiene
rubber, polyisoprene rubber, ethylene propylene rubber, butyl rubber,
halobutyl rubber, nitrile rubber, polyacrylic rubber, neoprene rubber,
hypalone rubber, silicone rubber, fluorocarbon rubber, polyurethane rubber,
etc are used to make a novel FGPs and FGPNCs.
In another embodiment of the present invention, various mixed polymer
matrixes i.e., combination of any two or more of the following polymers, i.e.,
natural rubber, styrene-butadiene rubber, polybutadiene rubber,
polyisoprene rubber, ethylene propylene rubber, butyl rubber, halobutyl
rubber, nitrile rubber, polyacrylic rubber, neoprene rubber, hypalone
rubber, silicone rubber, fluorocarbon rubber, polyurethane rubber, etc are
used to make a novel FGPs and FGPNCs.
In another embodiment of the present invention, various geometries i.e.,
rectangular, cylindrical, complex geometry, etc are used to make a novel
FGPs and FGPNCs using template.
In another embodiment of the present invention, various hollow geometries
i.e., rectangular, cylindrical including complex irregular geometry are used
to make a novel FGPNCs using template.
In another embodiment of the present invention, the gradient in properties
i.e., modulus, hardness, tensile strength, elongation at breaking point, tear
strength, strain energy density, hysteresis loss, work released during
retraction, etc are made in both directions.
Fig. 2: Variation of material properties with crosslinking density
DETAILED DESCRIPTION OF THE INVENTION
This invention provides a functionally graded polymers (FGPs) and
functionally graded polymer nanocomposites (FGPNCs) having a gradation of
crosslinking density, comprising of polymer(s) matrix, accelerator(s), curing
agent(s) nanomaterials(s), processing oil(s) and other chemicals i.e.,
antioxidant(s), accelerator, activator(s), etc.. The process for preparation of
the same involves the follows steps:
Conditioning of Materials
All materials except oil are kept in an oven in the temperature range of 50-
100°C for 1-5 hours to remove moisture. The polymers and nanomaterials
are weighed within a tolerance of ±lg. and all other chemicals are weighed
within a tolerance of ±0.1 g accuracy.
Mixing
Mixing of all chemicals in polymer matrix is carried out using two-roll mill at
a temperature of 50 to 125°C depending on the type of polymer. The speed
of front roll is in between 10 to 34 rpm and friction ratio between front and
rear roll is 1:1.1 to 1: 1.5. The clearance between rolls is adjustable from 0.1
to 12 mm. The formulation of the various mixes is given in Table 1.
(Table Removed)
In these formulations the amount of metal oxide/s, acid/s, processing oil/s
and antioxidant/s are in the range of 1 to 10 wt% (with respect to 100
polymer). Only the major variable is loading and type of curing agent/s,
accelerator/s and nanomaterial/s. Nanomaterials vary from 0 to 80 wt%
(with respect to 100 polymer). The curing agent/s and accelerator/s vary
from 1 to 350 wt% (with respect to 100 polymer). During mixing, at first
polymer is fed into the nip gap of two roll to get a thin sheet. Then
antioxidant(s) in powder form is added slowly followed by acid. The batch is
cut % of the distance across the roll with the help of a knife, and the knife is
held at this position until the bank just disappears. This process is
continued for about 10 minutes. Then nanomaterials(s) are added evenly
across the mill at a uniform rate. Processing oil(s) are added with and
without nanomaterials to get a good distribution of nanomaterials(s) into the
matrix. The materials falling through the nip is collected carefully from the
tray and returned back to the mix. The mixing cycle is concluded by passing
the rolled batch endwise through the mill six to eight times with an opening
of 0.2 mm to improve the dispersion. Finally, the mixed compound is passed
four times through the mill at a setting of 0.1 mm, folding it back on itself
each time. The batch is removed and kept on the glass sheet, in a closed
container to prevent absorption of moisture from the air for 24 hours. After
24 hours accelerator followed by curing agent is added according to
the procedure mentioned above.
.,,,„, ,, .. , ,. [weight of ingredintV,, Wt% of a particular ingredient = - * xi 0.„0
^ weight of polymer J
A thin uncured layer -0.1 mm (even less than 0.1 mm) of the mix was
prepared by pressing in between two teflon sheets in the hydraulic press (for
few seconds). The inner surfaces of the teflon sheets are coated with coating
agent for easy removal of the layer. The volume (thickness) of all the layers
of different mixes is made equal by taking different amount of mixes
according to the specific gravity of the chemicals. All these layers of
different mixes are stacked sequentially with increasing/decreasing amount
of nanomaterials in each layer to form green FGPs and FGPNCs.
Curing
Curing is carried out in the hydraulic press. The green FGPs and FGPNCs
are cut into pieces according to the dimension of the mold cavity using
template. Before putting the green FGPs and FGPNCs in the mould cavity,
the molding surfaces is polished and cleaned with distilled water and again
coated with mould releasing agent. The mold is kept at a curing temperature
of 100 to 250°C within ± 0.5°C depending on the type of base polymer in the
closed press, held at this temperature for at least 20 minute before the green
FGPs and FGPNCs are inserted. The temperature of the mold is controlled
by means of the temperature controller attached with the press. The press is
opened, the green FGPs and FGPNCs are inserted into the mold, and the
press is closed in the minimum time possible to prevent the excessive
cooling of the mold by contact with cool metal surfaces or by exposure to air
drafts. A pressure of 1 to 20 MPa is applied and three bumping is given to
remove the air bubbles present, if any for equal time of 15 sec. Finally, a
desired pressure is applied and the mold is held for 10 minutes to 8 hours
in the press. As soon as the press is opened the cure FGPs and FGPNCs
from the mold is removed and cooled in water for 10 to 15 min. The cured
FGPs and FGPNCs are conditioned at a temperature of 23±2°C for at least
16 hours before preparing the samples and testing.
This invention provides a functionally graded polymers (FGPs) and
functionally graded polymer nanocomposites (FGPNCs) having a gradation of
crosslinking density, comprising of polymer(s) matrix, accelerator(s), curing
agent(s) nanomaterials(s), processing oil(s) and other chemicals i.e.,
antioxidant(s'), accelerator(s), activator(s), etc.
A process for preparation of a FGPs and FGPNCs comprising the steps of:
- curing agent(s) and accelerator (s) as per user requirement (1 to 350 wt%,
with respect to 100 polymer) and/or nanomaterial(s) as per user
requirement (varies from 1 to 80% by weight, with respect to 100
polymer) and all other chemicals (wt% percentage is constant for these
chemicals) are imbedded in the polymer(s) matrix at the semisolid state
(i.e., above the glass transition temperature but below the melting point
of polymer) by the conventional two roll mixing mill
- a thin layer -0.1 mm is prepared from the oil(s) imbedded polymer(s)
matrix again by two roll mill and hydraulic press at the semisolid state
- this thin oil(s) imbedded polymer(s) matrix is optionally coated by both
sides with coating agent (i.e., silicone spray, soap solution, silicone
emulsion solution, stearic acid, polytetrafiuoro ethylene, polyvinyl
alcohol, etc)
- this thin coated/uncoated oil(s) imbedded polymer matrix is cut into the
required size using template
- the cut piece is laminated either increasing or decreasing order as per
requirement (shown in Fig 1) to get green FGPs and/or FGPNCs
- the green graded sheet is kept in the coated mould (coating of the mould
is done by any one of these silicone spray, soap solution, silicone
emulsion solution, stearic acid, polytetrafiuoro ethylene, polyvinyl
alcohol)
- the mould with green graded sheet is cured for a certain period of time at
a specified temperature and pressure to get a cure FGP and/or FGPNCs
(temperature is applied from one or both sides that depends on the type
of FGP and/or FGPNCs as shown in Fig 1)
- the cured FGP and/or FGPNCs is removed from the mould after curing
and cooled in room temperature and retained for 24 hours for further
characterization.
The polymer matrix is selected from the group comprising of natural rubber,
polyisoprene rubber, styrene-butadiene rubber, polybutadiene rubber,
ethylene-propylene rubber, ethylene-propylene diene-monomer rubber, butyl
rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile rubber,
polysulfide rubber, polyacrylic rubber, neoprene rubber, hypalon rubber,
silicone rubber, fluorocarbon rubber, polyurethane rubber, thermoplastic
elastomer, and mixture thereof.
The polymer matrix natural rubber is selected from the group comprising of
standard malaysian rubber (SMR) L, SMR CV, SMR WF, SMR GP, SMR LV,
SMR 5, SMR 10, SMR 20, SMR 50, technically specified rubbers (TSR) 5,
TSR 10, TSR 20, TSR 50, technically classified rubber, oil extended natural
rubber, deproteinized natural rubber, peptized natural rubber, skim natural
rubber, superior processing natural rubber, heveaplus MG rubber,
epoxidized natural rubber, thermoplastic natural rubber, and mixture
thereof; the polymer matrix styrene-butadiene rubber is selected from the
group comprising of solution styrene-butadiene rubber i.e., SBR 2305, SBR
2304, emulsion styrene-butadiene rubber i.e., cold SBR 1500, cold SBR
1502, hot SBR 100, and mixture thereof; the polymer matrix polybutadiene
rubber is selected from the group comprising of cisamer-01, cisamer!220,
BR 9000, BR 9004A, BR 9004B, low molecular weight 1, 3 polybutadiene,
and mixture thereof; the polymer matrix butyl rubber is selected from the
group comprising of IIR-1751, IIR-1751F, IIR-745, Exxon butyl 007, Exxon
butyl 065, Exxon butyl 068, Exxon butyl 165, Exxon butyl 268, Exxon butyl
269, Exxon butyl 365, polysar butyl 100, polysar butyl 101, polysar butyl
101-3, polysar butyl 301, polysar butyl 402, and mixture thereof; the
polymer matrix ethylene-propylene rubber is selected from the group
comprising of dutral-CO-034, dutral-CO-038, dutral-CO-043, dutral-CO-054,
dutral-CO-058, dutral-CO-059, dutral-CO-055, and mixture thereof; the
polymer matrix ethylene-propylene- diene-monomer rubber is selected
from the group comprising of ethylene-propylene-dicyclopentadiene rubber,
ethylene-propylene-ethylidenenorbornene rubber, ethylene-propylene-1, 4
hexadiene rubber, and mixture thereof; the polymer matrix halobutyl rubber
is selected from the group comprising of Exxon chlorobutyl 1065, Exxon
chlorobutyl 1066, Exxon chlorobutyl 1068, Polysar chlorobutyl 1240,
Polysar chlorobutyl 1255, Exxon bromobutyl 2222, Exxon bromobutyl 2233,
Exxon bromobutyl 2244, Exxon bromobutyl 2255, Polysar bromobutyl X2,
Polysar bromobutyl 2030, and mixture thereof; the polymer matrix nitrile
rubber is selected from the group comprising of Krynac-2750, Nipol-1053,
Nipol-1032, Paracril-C, Chemigum-N-3, Krynac-5075, and mixture thereof;
the polymer 'matrix hydrogenated nitrile rubber is selected from the group
comprising of zetpol-1010, zetpol-1020, zetpol-2010, zetpol-2020, and
mixture thereof; the polymer matrix polyacrylic rubber is selected from the
group comprising of hycar-4051, hycar-4052, hycar-4054, vamac-B-124,
and mixture thereof; the polymer matrix neoprene rubber is selected from
the group comprising of neoprene-AC, neoprene-AD, neoprene-ADG,
neoprene-AF, neoprene-AG, neoprene-FB, neoprene-GN, neoprene-GNA,
neoprene-GRT, neoprene-GS, neoprene-GW, neoprene-W, neoprene-W-MI,
neoprene-WB, neoprene-WD, neoprene-WHV, neoprene-WHV-100,
neoprene-WHV-200, neoprene-WHV-A, neoprene-WK, neoprene-WRT,
neoprene-WX, neoprene-TW, neoprene-TW-100, neoprene-TRT, and mixture
thereof; the polymer matrix hypalon rubber is selected from the group
comprising of hypalon-20, hypalon-30, hypalon-LD-999, hypalon-40S,
hypalon-40, hypalon-4085, hypalon-623, hypalon-45, hypalon-48S,
hypalon-48, and mixture thereof; the polymer matrix silicone rubber is
selected from the group comprising of silicone MQ, silicone MPQ, silicone
MPVQ, silicone FVQ, and mixture thereof; the polymer matrix fluorocarbon
rubber is selected from the group comprising of viton-LM, viton-C-10,
viton-A-35, viton-A, viton-A-HF, viton-E-45, viton-E-60, viton-E-60C,
viton-E403, viton-B-50, viton-B, viton-B-70, viton-910, viton-GLT, viton-
GF, viton-VTR-4730, DAI-EL-G-101, DAI-EL-701, DAI-EL-751, DAI-EL-
702, DAI-EL-704, DAI-EL-755, DAI-EL-201, DAI-EL-501, DAI-EL-801, DAIEL-
901, DAI-EL-902, tecnoflon-FOR-LHF, tecnoflon-NMLB, tecnoflon-NML,
tecnoflon-NMB, tecnoflon-NM, tecnonon-NH, tecnoflon-FOR-45-45BI,
tecnoflon-FOR-70-70BI, tecnoflon-FOR-45-C-CI, tecnonon-FOR-60K-KI,
tecnoflon-FOR-50E, tecnoflon-TH, tecnoflon-TN-50, tecnoflon-TN, tecnoflon-
FOR-THF, tecnoflon-FOR-TF-50, tecnoflon-FOR-TF, fluorel-2145, fluorel-FC-
2175, fluorel-FC-2230, fluorel-FC-2178, fluorel-FC-2170, fluorel-FC-2173,
fluorel-FC-2174, fluorel-FC-2177, fluorel-FC-2176, fluorel-FC-2180, fluorel-
FC-81, fluorel-FC-79, fluorel-2152, fluorel-FC-2182, fluorel-FC-2460,
fluorel-FC-2690, fluorel-FC-2480, and mixture thereof, the polymer matrix
polyurethane rubber (polyether and polyester type) is selected from the
group comprising of FMSC-1035, FMSC-1035T, FMSC-1040, FMSC-1050,
FMSC-1060,' FMSC-1066, FMSC-1070, FMSC-1075, FMSC-1080-SLOW,
FMSC-1080-FAST, FMSC-1085, FMSC-1090-FAST, FMSC-1090-SLOW, and
mixture thereof; the polymer matrix thermoplastic elastomer (polyurethane,
polyester, polyamide, styrene-butadiene-styrene, blends, etc) is selected
from the group comprising of SBS 1401, SBS 4402, SBS 4452, SBS 1301,
SBS 1401-1, SBS 4303, estane-55103, hytrel-40xy, hytrel-63xy, hytrel-
72xy, gaflex-547, pebax-2533, pebax-6333, TPR-1600, TPR-1900, TPR-
-11-
2800, TELCAR-340, SOMEL-301, SOMEL-601, santoprene, cariflex-TR,
solprene-400, stereon, and mixture thereof; the polymer matrix polysulfide
elastomer is selected from the group comprising of thiakol-A, thiakol-B,
thiakol-FA, thiakol-ST, and mixture thereof;
The polymer matrix natural rubber is cured by vulcanizing agent selected
from the group comprising of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, diurethane, and mixture thereof which is in the range of 1
to 350 wt% (with respect to 100 polymer); the polymer matrix styrenebutadiene
rubber is cured by vulcanizing agent selected from the group
comprising of sulphur, hydrogen peroxide, dicumyl peroxide, benzoyl
peroxide, diurethane, and mixture thereof which is in the range of 1 to 350
wt% (with respect to 100 polymer); the polymer matrix poly butadiene rubber
is cured by vulcanizing agent selected from the group comprising of sulphur,
hydrogen peroxide, dicumyl peroxide, benzoyl peroxide, diurethane, and
mixture thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix butyl rubber is cured by vulcanizing agent
selected from the group comprising of sulphur, hydrogen peroxide, dicumyl
peroxide, benzoyl peroxide, diurethane, p-quinone dioxime, p-quinone
dioxime dibenzoate, phenol-formaldehyde resin, and mixture thereof which
is in the range of 1 to 350 wt% (with respect to 100 polymer); the polymer
matrix ethylene-propylene rubber is cured by vulcanizing agent selected
from the group comprising of hydrogen peroxide, dicumyl peroxide, benzoyl
peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy) hexane,
bis(2,4-dichloro-benzoyl) peroxide, and mixture thereof which is in the range
of 1 to 350 wt% (with respect to 100 polymer); the polymer matrix ethylenepropylene-
diene-monomer rubber is cured by vulcanizing agent selected
from the group comprising of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, diurethane, and mixture thereof which is in the range of 1
to 350 wt% (with respect to 100 polymer); the polymer matrix halobutyl
rubber is cured by vulcanizing agent selected from the group comprising of
sulphur, hydrogen peroxide, dicumyl peroxide, benzoyl peroxide, zinc oxide,
p-quinone dioxime, p-quinone dioxime dibenzoate, phenol-formaldehyde
resin, amine, and mixture thereof which is in the range of 1 to 350 wt%
(with respect to 100 polymer); the polymer matrix nitrile rubber is cured by
vulcanizing agent selected from the group comprising of sulphur, hydrogen
peroxide, dicumyl peroxide, benzoyl peroxide, and mixture thereof which is
in the range of 1 to 350 wt% (with respect to 100 polymer); the polymer
matrix hydrogenated nitrile rubber is cured by vulcanizing agent selected
from the group comprising of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy)
hexane, bis(2,4-dichloro-benzoyl) peroxide, tertiary butyl perbenzoate, and
mixture thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix polyacrylic rubber is cured by vulcanizing
agent selected from the group comprising of amine, diamine, activated thiol,
sulphur, thiourea, trithiocyanuric acid, hydrogen peroxide, dicumyl
peroxide, benzoyl peroxide, and mixture thereof which is in the range of 1 to
350 wt% (with respect to 100 polymer); the polymer matrix neoprene rubber
is cured by vulcanizing agent selected from the group comprising of
magnesium oxide, zinc oxide, lead oxide, iron oxide, titanium oxide, amine,
phenol, sulfenamide, thiazoles, thiuram, thiourea, guanidine, and mixture
thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix hypalon rubber is cured by vulcanizing agent
selected from the group comprising of magnesium oxide, zinc oxide, lead
oxide, iron oxide, titanium oxide, sulphur, hydrogen peroxide, dicumyl
peroxide, benzoyl peroxide, N,N'-m-phenylenedimaleimide, amine, phenol,
sulfenamide, thiazoles, thiuram, thiourea, guanidine, and mixture thereof
which is in the range of 1 to 350 wt% (with respect to 100 polymer); the
polymer matrix silicone rubber is cured by vulcanizing agent selected from
the group comprising of hydrogen peroxide, dicumyl peroxide, benzoyl
peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy) hexane,
bis(2,4-dichloro-benzoyl) peroxide, tertiary butyl perbenzoate, and mixture
thereof which is in the range of 1 to 350 wt% (with respect to 100 polymer);
the polymer matrix fluorocarbon rubber is cured by vulcanizing agent
selected from the group comprising of hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy)
hexane, bis(2,4-dichloro-benzoyl) peroxide, tertiary butyl perbenzoate,
hexamethylenediamine carbamate, bis(cinnamylidene)
hexamethylenediamine, hydroquinone, 4-4'-isopropylidene bisphenol or
mixture thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix polyurethane rubber (polyether and polyester
type) is cured by vulcanizing agent selected from the group comprising of
1,4-butanediol, 1,4-cyclohexanedimethanol, 1,4-bis(2-hydroxyethoxy)
benzene, 4,4'methylene~bis(2-chloroaniline), and mixture thereof which is in
the range of 1 to 350 wt% (with respect to 100 polymer); the polymer matrix
thermoplastic elastomer (polyurethane, polyester, polyamide, styrenebutadiene-
styrene, blends, etc) is cured by vulcanizing agent selected from
the group comprising of lead oxide, cadmium oxide, zinchydroxide, hydrogen
peroxide, dicumyl peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-
dimethyl-2,5-bis (t-butyl peroxy) hexane, bis(2,4-dichloro-benzoyl) peroxide,
tertiary butyl perbenzoate, and mixture thereof which is in the range of 1 to
350 wt% (with respect to 100 polymer); and the polymer matrix polysulfide
elastomer is cured by vulcanizing agent selected from the group comprising
of lead oxide, cadmium oxide, zinchydroxide, hydrogen peroxide, dicumyl
peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl
peroxy) hexane, bis(2,4-dichloro-benzoyl) peroxide, tertiary butyl
perbenzoate, hexamethylenediamine carbamate, bis(cinnamylidene)
hexamethylenediamine, hydroquinone, 4-4'-isopropylidene bisphenol, and
mixture thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer).
The curing of polymer matrix comprising of either natural rubber,
polyisoprene rubber, styrene-butadiene rubber, polybutadiene rubber,
ethylene-propylene rubber, ethylene-propylene diene monomer rubber, butyl
rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile rubber,
polysulfide elastomer, polyacrylic rubber, neoprene rubber, hypalon rubber,
silicone rubber, fluorocarbon rubber, polyurethane rubber, thermoplastic
elastomer and/or mixture thereof is further accelerated by accelerator
selected from the group COMPRISING of tert-buttylbenzthiazyl
sulphonamide, benzthiazyl 2-sulphenmorpholide, dicyclohexyl benzthiazyl
sulphonamide, N-cyclohexyl-2-benzothiazole sulfenamide, 2-
mercaptobenzothiazole, 2,2'dibenzothiazyl disulfide, tetramethylthiuram
disulfide, zinc dimethyldithiocarbamate, zinc
dibutyldithiocarbamate, 4,4'dithiodimorpholine, tellurium
diethyldithiocarbamate, dipentamethylene thiuramhexasulfide,
tetramethylthiuram monosulfide, ferricdimethyldithiocarbamate, zinc
mercaptobenzthiazole, zinc 0,0 dibutylphosphorodithioate, zinc
diethyldithiocarbamate, 4-4'dithio dimorpholine, which is in the range of 1
to 350 wt% (with respect to 100 polymer) and , and mixture thereof in a
ratio of 1 : 9 to 9:1 (by weight)
The polymer matrix comprising of either natural rubber, polyisoprene
rubber, styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene
rubber, ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylic rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer and/or
mixture thereof is graded by carbon nanoparticles selected from the group
COMPRISING of N-110, N-115, N-120, N-121, N-125, N-134, N-135, N-212,
N-220, N-231, N-234, N-293, N-299, N-315, N-326, N-330, N-335, N-339, N-
343, N-347, N-351, N-356, N-358, N-375, N-539, N-550, N-582, N-630, N-
642, N-650, N-660, N-683, N-754, N-762, N-765, N-772, N-774, N-787, N-
907, N-908, N-990, N-991, and mixture thereof which is in the range of 0 to
80 wt% (with respect to 100 polymer).
The polymer matrix comprising of either natural rubber, polyisoprene
rubber, styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene
rubber, ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylic rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer and/or
mixture thereof is further graded by various silica nanoparticles i.e.,
precipitated silica (i.e., HS-200, HS-500, HS-700, etc), fumed silica and
mixture thereof which is in the range of 0 to 80 wt% (with respect to 100
polymer).
The polymer matrix comprising of either natural rubber, polyisoprene
rubber, styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene
rubber, ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylic rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer and/or
mixture thereof is further graded by clay nanoparticles which is in the range
of 0 to 80 wt% (with respect to 100 polymer).
The polymer matrix COMPRISING of either natural rubber, polyisoprene
rubber, styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene
rubber, ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylic rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer and/or
mixture thereof is further graded by mixed carbon nanoparticles, nanosilica
and nanoclay in a volume ratio of 5:2:1 to 1:2:5 selected from the group
COMPRISING of N-110, N-115, N- 120, N-121, N-125, N-134, N-135, N-
212, N-220, N-231, N-234, N-293, N-299, N-315, N-326, N-330, N-335, N-
339, N-343, N-347, N-351, N-356, N-358, N-375, N-539, N-550, N-582, N-
630, N-642, N-650, N-660, N-683, N-754, N-762, N-765, N-772, N-774, N-
787, N-907, N-908, N-990, N-991, precipitated silica (i.e., HS-200, HS-500,
HS-700, etc), fumed silica, clay and mixture thereof.
The polymer matrix COMPRISING of either natural rubber, polyisoprene
rubber, styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene
rubber, ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylic rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer and/or
mixture thereof is further graded by mixed carbon nanoparticles having
same concentration gradient but different particle size i.e 5 to 85 nm and
selected from the group COMPRISING of N-110, N-115, N-120, N-121, N-
125, N-134, N-135, N-212, N-220, N-231, N-234, N-293, N-299, N-315, N-
326, N-330, N-335, N-339, N-343, N-347, N-351, N-356, N-358, N-375, N-
539, N-550, -N-582, N-630, N-642, N-650, N-660, N-683, N-754, N-762, N-
765, N-772, N-774, N-787, N-907, N-908, N-990, N-991.
The curing of polymer matrix COMPRISING of either natural rubber,
polyisoprene rubber, styrene-butadiene rubber, polybutadiene rubber,
ethylene-propylene rubber, ethylene-propylene diene monomer rubber, butyl
rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile rubber,
polysulfide elastomer, polyacrylic rubber, neoprene rubber, hypalon rubber,
silicone rubber, fluorocarbon rubber, polyurethane rubber, thermoplastic
elastomer and/or mixture thereof is further accelerated by accelerator
activator selected from the group COMPRISING of metal oxide and acid
which is in the range of 10:1 to 1:10 wt% (with respect to 100 polymer).
The metal oxide used in accelerator activator is selected from the group
COMPRISING of zinc oxide, lead oxide, calcium oxide, magnesium oxide,
lead oxide, etc which is in the range of 1 to 10 wt% (with respect to 100
polymer).
The acid used in accelerator activator is selected from the group
COMPRISING of stearic acid, palmitic acid, oleic acid, etc which is in the
range of 1 to 10 wt% (with respect to 100 polymer).
The FGPs and FGPNCs further comprises an antioxidant selected from the
group COMPRISING of condensation product of acetone and diphenylamine,
phenyl-beta-napthylamine, blends of diphenyl-p-phenylene diamine
and selected arylamine derivatives, blend of arylamines, polymerized 1,2
dihydro 2,2,4-trimethyl quinoline, N-(l,3-dimethylbutyl)-N'-phenyl-pphenylene-
diamine, diaryl para phenylene diamines, 2
mercaptobenzimidazole, and mixture thereof which is in the range of 1 to
10 wt% (with respect to 100 polymer).
The FGPs and FGPNCs further comprises a process oil selected from
the group COMPRISING of paraffinic oil, naphthenic oil, aromatic oil,
vegetable oil, and mixture thereof which is in the range of 1 to 10 wt% (with
respect to 100 polymer).
The nanoparticles and other chemicals imbedded polymer matrix is
prepared by mixing the polymer and other compounding ingredients by
conventional methods such as open roll mixing using two roll mill and
internal mixing kneader, intermix and banbary rnixer.
The thin polymer layer (before curing) is prepared by two roll mill at a
temperature range from about 50°C to about 125°C depending on the type of
rubber, and at a friction ratio from about 1:1.1 to about 1:1.5 to selectively
produce a thin layer within the range of 0.1 to 10 mm in thickness.
The thin polymer layer is optionally coated by one or more coating agent
selected from the group COMPRISING of polytetrafluoro ethylene, polyvinyl
alcohol, silicone emulsion and detergent/soap solution.
The green graded material is prepared by laminating of thin polymer layer to
produce a rectangular sheet having a thickness within the range of 2 to
1000 mm or unlimited in higher side, or cylindrical shape having a diameter
within the range of 10 to 100 mm or unlimited in higher side.
The green graded material of rectangular/cylindrical shape is cured by
hydraulic press in the temperature range of 100°C to about 250°C for 10
minutes to about 8 hours and at pressure in the range of 1 MPa to about 20
MPa.
The wt fraction of curative(s) and accelerator(s) is varied within the range of
1 to 350% from the inner surface to outer surface (Figl) or from outer
surface to inner surface (Figl) or from outer surface to outer surface i.e.,
opposite surface (Fig 1).
The orifice both regular and irregular, i.e., complex geometry including its
dimension (as shown in Figl) were made from one surface to the opposite
surface using template; and the concentration of curative(s) and
accelerator (s) at the inner surface could be varied from 1 to 350% by wt%
(with respect to 100 polymer) (maximum) depending on the requirement;
and the dimension of orifice could be varied using template.
Specific gravity
Specific gravity of FGPs and FGPNCs is measured by the specific gravity
balance.
Hardness
Shore A type durometer is used to measure the hardness of FGPs and
FGPNCs. The method adopted is the same as that of ASTM D2240-81.
Modulus, Tensile Strength and Elongation at Break
Modulus, tensile Strength and elongation at break are determined according
to the ASTM D4 12-80 test method using dumbbell shaped specimens.
Samples are punched along the mill grain direction from the cured sheet
using ASTM type dumbbell cutting die. The thickness of the narrow portion
of the specimen is measured using a bench thickness guage. The tests are
carried out in Zwick Universal Testing Machine (UTM) interfaced with a
computer. All tests are carried out at 500 mm/min. cross head speed. The
tests at elevated temperatures are done using a temperature cabinet
equipped with a temperature controller. The modulus and tensile strength
are reported in MPa and the elongation break in percentage.
Tear Strength
Tear strength is measured in Zwick (UTM) using unnotched 90° angled tear
test specimen (die C) as per ASTM D 624-73. The samples are punched out
from the molded sheet of FGPs and FGPNCs. The speed of crosshead is
adjusted to 500 mm/min.
Hysteresis
Hysteresis loss of materials is defined as the amount of energy dissipated
during cyclic deformation determined from the area under work done during
extension (W;) and work done during retraction (W2) when the specimen are
stretched to varying extent and rate of elongation and then allowed to
retract at the same rate to the unstretched state.
Hy = (Wi-Wa )
Work done during extension (Wi) or strain energy is the area under the force
deflection curve upto a fixed deflection and is expressed in joule. When it is
divided by the volume of the test piece, it is known as the strain energy
density, which is expressed in J/m3. Hysteresis loss ratio is another
parameter, which plays important role in the study of mechanical properties
of materials. It is defined, as the energy dissipated relative to the energy
supplied on stretching, and determined from the following expression.
Dynamic mechanical properties:
Owing to the viscoelastic nature of polymers, the sinusoidal strain lags the
stress by an 'angle when the stress is applied to the sample. Accordingly the
stress can be resolved into two components: one in phase with the strain
and the other 90° out of phase. The complex modulus, storage modulus,
loss modulus, complex compliance, storage compliance, loss compliance, etc
are measured in bending mode over a range of frequency (0.01 to 100 Hz),
temperature (+25 to 100°C) and a peak to peak displacement 4x64 microns
with a heating rate of 5°C per minute. Owing to the small dimensions of the
specimens, the wave effect is absent, i.e., the phase of deformation of the
entire specimen is same at any moment of time. In the case of
multifrequency measurement, the changeover from one frequency to another
is automatic. These data are analyzed for FGPs and FGPNCs.
Crosslinking Density
The crosslinking density was measured by Flory-Rehner equation
Where, Vr, Vs, %, "Hsweii, and f are volume fraction of polymer in swollen gel
(cm3/mol), molar volume fraction of toluene, polymer-solvent interaction
parameter, crosslink density of polymer (mol/ cm3 ) and functionality of
crosslinks respectively
Fig 3: Variation of crosslink density with too high curatives concentrations
and distance.
To see the extent to which the crosslink density can be increased, the
concentrations of both sulfur and accelerator in SBR are increased along the
thickness direction up to 350 wt% (with respect to 100 polymer) levels each.
From the Fig. 3, the crosslink density of nanosized carbon black filled
FGPNCs at the sulfur and accelerator concentrations of 11 wt% (with
respect to 100 polymer) each is (37 x 10-4 mol/cc) even more compared to
the crosslink density (36 x 10-4 mol/cc) of unfilled FGPs at the
concentrations (25 wt%, with respect to 100 polymer each) of sulfur and
accelerator both. At the sulfur and accelerator concentrations of 150 wt%
(with respect to 100 polymer), the values of the crosslink density come closer
(181 x 10-* mol/cc for carbon black filled FGPNCs and 179 x 10-4 mol/cc
for unfilled FGPs) indicating the saturation limit in the offing. Finally at the
concentrations of 200 wt% (with respect to 100 polymer) and above,
saturation levels of crosslink density reaches and the curve plateaus. The
saturation values of crosslink density of filled and unfilled functionally
graded materials are 210 x 10-4 mol/cc and 192 x 10-4 mol/cc respectively.
The crosslink density of the unfilled FGPs is increased from 14 x 10 4 to 192
x 10-4 mol/cc ie. ~ 14 times along the span of 6 mm while for the filled
FGPNCs it is increased from 17 x 10-4 to 210 x 10-4 mol/cc ie. ~ 12 times
along the span of 5.5 mm thick vulcanizate.
Fig. 4(a) Variation of hardness and specific gravity of unfilled FGPs and (b) 40 wt%
nanosized carbon black filled FGPNCs along the thickness of the sheet. The
concentration of crosslinking density varies from one surface to the opposite
surface, whereas the concentration of nano sized amorphous carbon is same
throughout the surface
Fig. 4 demonstrates that the hardness increases with increasing distance
from one end to the opposite end. The hardness value in FGPs varies from
47 to 70 shore A as shown in Fig 4(a). Specific gravity increases linearly
along distance from 0.98 to 1.05. Hardness increases significantly by 46%
while the increase in specific gravity is only 7%. Fig. 4(b) demonstrates that
hardness increases with increasing distance from one end to the opposite
end. Its magnitude of the filled FGPNCs varies from 65 to 88 shore A.
Specific gravity increases linearly along distance from 1.11 to 1.16 as shown
in Fig. 4(b) and is slightly higher compared to unfilled FGPCs as the specific
gravity of carbon black is 1.8. Hardness increases significantly by 35 %
while the increase in specific gravity is only 4.5%. To see the extent to which
the crosslink density can be maximized, the sulfur and accelerator
concentrations are increased up to 350 wt% each and the maximum
hardness measured is 90 shore D at 100 wt%. After this, hardness nearly
remains constant even when the crosslink density and other dynamic
mechanical properties continue to grow. Specific gravity at 100 wt% is 1.4
and at 350 wt% is 1.6.
Nanocomposites
Fig. 5 Stress-elongation profile of (a) unfilled FGPs and (b) 40 wt% nanosized
amorphous carbon black filled FGPNCs of different layers containing varied
crosslink rif»nsitv alonn the thickness of the* sheet
Fig. 6 Strain energy-elongation profile of (a) unfilled FGPCs and (b) 40 wt%
nanosized amorphous carbon black filled FGPNCs of different layers
containing varied crosslink density.
Figs. 5 and 6 reveal the stress-strain/elongation and strain energyelongation
profiles for unfilled and nanosized carbon filled FGPNCs at
different distances from one end to the opposite end. For unfilled FGPs as
shown in Fig. 5(a), the layer at an average distance of 0.25 mm extends by
more than 900 % with a stress value of 1.7 MPa, which is much more than
the opposite, layer (100 %) present at a distance of 2.75 mm. For the
nanosized amorphous carbon black filled FGPNCs, the layer at a distance of
0.12 mm extends by more than 1200 % with a stress value of 16.2 MPa,
which is much more than the opposite layer (115 %) with a stress value of
11 MPa at a distance of 2.9 mm. Similar trends as shown in Fig. 5 are also
observed when strain energy is plotted against deformation/elongation. For
unfilled FGPCs as shown in Fig". 6(a), the strain energy of the layer present
at an average distance of 0.25 mm is nearly 6 folds higher than that of
opposite layer at a distance of 2.75 mm. The values of the strain energy at
0.25 and at 2.75 mm are 5.3 x 1Q5 and 0.86 x 105 J/m2 respectively.
Similarly in filled FGPNCs, the strain energy of the layer present at an
average distance of 0.12 mm is nearly 13 folds higher than that of opposite
layer at a distance of 2.87 mm. The values of the strain energy at 0.12 and
at 2.87 mm are 4.9 x 10<> and 3.85 x 105 j/m2 respectively.
Fig. 7 Variation of tensile strength and elongation at break (a) of unfilled FGPs
and (b) 40 wt% nanosized carbon black filled FGPNCs of different layers
containing varied crosslink density.
For unfilled FGPs (Fig. 7(a)), the tensile strength is continuously increasing
along thickness from 1.7 to 2.7 MPa and elongation at breaking point is
continuously decreasing along thickness from 900 to 100 % respectively
within the span of 3 mm. Tensile strength at breaking point increases to 63
% and while elongation decreases by 89 % respectively. For the filled
FGPNCs ((Pig. 7(b))), the tensile strength increases from 14.8 to 17.4 MPa
and then decreases from 17.4 to 11.6 MPa, whereas elongation at breaking
point is continuously decreasing from 1020 to 115 % within the span of 3
mm.
Modulii at 50 and 100 % elongations increase from one end to other
end as shown in Fig. 8. In unfilled FGPs, the values of modulus at 50 and
100 % elongations increase from 0.5 to 1.5 and 0.8 to 2.7 MPa respectively.
Modulus at 50% elongation increases by 285% while modulus at 100% lifts
up by 335% in the span of 3 mm. For nano sized carbon black filled
FGPNCs, the values of modulus at 50 and 100 % elongations increase from
1.0 to 4.8 and 1.3 to 9.9 MPa respectively. Modulus at 50 % elongation
increases by 465% while modulus at 100 % lifts up by 760% in the span of
3 mm.
Fig. 8 Modulus at 50 and 100 % elongation profiles of (a) unfilled FGPs and
(b) 40 wt% nano sized carbon black filled FGPNCs of different layers
containing varied crosslink density.
The variation of tear strength with cross linking density is not linear as of
tensile strength, elongation and modulii curves (Fig.9). The tear strength
enhances from 11.5 to 14.8 kN/m before reaching the mid-thickness,
maintains nearly 13.7 kN/m just before the end and drops down drastically
to 10.7 kN/m at the end (Fig. 9(a)). Fig. 9(b) shows that the tear strength
and tear elongation at break both decrease along thickness. The tear
strength decreases from 52 to 17 kN/m while elongation at break reduces
from 600% to 24 %. Tear strength decreases by 33 % while elongation
decreases by 96 % while moving from one end to the other end along
distance.
Fig. 9 Tear strength and elongation at break profiles of (a) unfilled FGPCs
and (b) 40 wt% nano sized carbon black filled FGPNCs of different layers
containing varied crosslink density.
Fig. 10 (a) Hystersis loss and strain energy at 100 % deformation measured in
the first cycle of unfilled FGPCs and (b) 40 wt% carbon black filled FGPNCs of
different layers containing varied crosslink density.
Hysteresis loss, hysteresis loss ratio and strain energy during deformation
at 100% strain are measured over a number of cycles (upto!0th cycle) to
understand their behaviour in target application. As shown in Fig. 10(a), for
unfilled FGPs, the values of the hysteresis loss in the first cycle at 0.25 and
at 2,75 mm are 3.4 and 2.75 kJ/m2 respectively while energy values at the
same positions are 11 and 27.5 kJ/m2 respectively. The lowest value of
hysteresis loss corresponding to 3 wt% curing agent and accelerator is 1.3
kJ/m2. Fig. 10(b) shows the gradual increase in the hysteresis loss along
the distance as the cross linking density increases for the filled FGPNCs.
The values of the hysteresis losses in the first cycle along thickness at 0.125
and at 2.875 mm are 27 and 131 kJ/m2 respectively while energy values at
the same positions are 63 and 290 kJ/m2 respectively. Strain energy during
deformation and strain energy during retraction {Fig. 10) follow same trend
and increases continuously as the amount of energy needed for the given
deformation increases due to increase in the crosslink density. As the
concentrations of sulfur and accelerator increase from one surface to the
opposite surface along thickness direction, the parameters like hysteresis
loss, hysteresis loss ratio, strain energy during deformation and strain
energy during retraction depend on distance of the FGPs and FGPNCs,
where all these properties are measured. Same trend is also observed at 4*
cycles (Fig. 11)
Fig. 11 (a) Hystersis loss and strain energy at 100 % deformation measured in
the fourth cycle of unfilled FGPs and (b) 40 wt% carbon black filled FGPNCs of
different layers containing varied crosslink density along the thickness of the
sheet.
Fig. 12 Variation of storage modulus of different layers carrying varied
crosslink density of (a) unfilled FGPs and (b) 40 wt% carbon black filled
FGPNCs along the thickness of the sheet.
-100 -80 -60 -40 -20 0 20 40 60
Temperature(°C)
Now the FGPs are characterized under dynamic conditions to understand its
performance under repeated number of deformations and bending mode
over a range of temperatures from -100 to 100 °C at 10 Hz. Fig 12(a) shows
the variation of storage modulus with temperature for unfilled FGPs made of
styrene butadiene rubber matrix and the varied amounts (1 to 11 wt%) of
sulfur and accelerator. At -100 °C, the storage modulus of the layer present
at an average distance of 2.75 mm, where the concentration of sulfur and
accelerator is maximum (11 wt%), is somewhat more than the layer at a
distance of 0.25 mm along the thickness direction, where the concentration
of curatives is less (1 wt%). The values of storage modulus at -100 °C at an
average distance of 2.75 and 0.25 mm are 1.3 x IQio and 1.1 x 10i° Pa
respectively. The storage modulus values of these layers present at 2.75 mm
and 0.25 mm at 0 «C are 6.5 x 109 pa and 1.5 x 10? Pa respectively. Fig.
12(b) shows the variation in the storage modulus with temperature for the
carbon black filled FGPNCs carrying varied amounts of sulfur and
accelerator. At -100 °C, the storage modulus at an average distance of 2.875
mm, where the concentrations of sulfur and accelerator are maximum (11
wt%), is roughly 2 times more than the layer present at an average distance
of 0.125 mm along the thickness direction, where the concentration of
curatives is less (1 wt%). The values of storage modulus at -100 °C at a
distance of 2.875 and 0.125 mm are 7.5 x 109 and 4.3 x!Q9 Pa respectively.
Similarly the corresponding modulus values at 0 °C are 8.54 x 109 Pa and
2.57 x 108 Pa respectively.
Fig. 13 storage modulus of much higher crosslink density of (a) unfilled FGPs
and (b) 40 wt% carbon black filled FGPNCs along the thickness of the sheet.
Fig. 14 Variation of complex modulus of different layers carrying varied
crosslink density of (a) unfilled FGPs and (b) 40 wt% carbon black filled
FGPNCs along the thickness of the sheet.
When the amounts of the sulfur and accelerator concentrations become
much higher i.e. when the crosslink density increases to a much higher
extent, following are the conclusions which can be drawn from the Fig. 13.
At room temperature shown in Fig. 13(a), the storage modulus of unfilled
FGPs at a distance of 6 mm, where the concentration of sulfur and
accelerator is maximum (350 wt%), is 3 decades more than the layer at a
distance of 0.4 mm along the thickness direction, where the concentration of
curatives is the least (1 wt%). The values of storage modulus at a distance of
6.0 and 0.4 mm are 1.4 x 10Jo and 4 x 10? Pa respectively. For filled
FGPNCs (Fig. 13(b)j , at room temperature, the storage modulus at a
distance of 5.5 mm, where the concentration of sulfur and accelerator is
maximum (350 wt%), is 3 decades more than the layer at a distance of 0.25
mm along the thickness direction, where the concentration of curatives is
less (1 wt%). The values of storage modulus at a distance of 5.5 and
0.25 mm are L.67 x 1010 and 1 xlO^ Pa respectively.
Fig. 14(a) shows the variation of complex modulus with temperature for
FGPs made of styrene butadiene rubber matrix and the varied amounts (1 to
11 wt%) of sulfur and accelerator. The values of complex modulus at -100 °C
at an average distance of 2.75 and 0.25 mm are 1.36 x 1010 and 1.13 x 1010
Pa respectively. The complex modulus values of these layers present at 2.75
mm and 0.25 mm at QOC are 6.57 x 10$ Pa and 1.54 x 10? Pa respectively.
Fig. 14(b) shows the variation in the complex modulus with temperature for
the carbon black filled FGPNCs carrying varied amounts of sulfur and
accelerator. The values of complex modulus at -100 °C at a distance of
2.875 and 0.125 mm are 7.58 x 10^ and 4.33 xlO^ Pa respectively. Similarly
the corresponding modulus values at 0 °C are 8.59 x 109 Pa and 2.6 x 108
Pa respectively.
The various curves correspond to the sulfur and accelerator
concentrations of 25 to 350 wt% are shown in Fig. 15. At room temperature,
the complex modulus at a distance of 6 mm, where the concentration of
sulfur and accelerator is maximum (350 wt%), is 3 decades more than the
layer at a distance of 0.4 mm along the thickness direction, where the
concentration of curatives is the least (1 wt%). For the filled FGPNCs as
shown in Fig. 15(b), at room temperature, the complex modulus at a
distance of 5.5 mm, where the concentration of sulfur and accelerator is
maximum (350 wt%), is 3 decades more than the layer at a distance of 0.25
mm along the thickness direction, where the concentration of curatives is
the least (1 wt%). The values of complex modulus at a distance of 5.5 and
0.25 mm are 1.72 x IQio and 9.5 xlO? Pa respectively.
Fig. 15 Complex modulus of much higher crosslink density of (a) unfilled
FGPs and (b) 40 wt% carbon black filled FGPNCs along the thickness of the
sheet.
Pig 16 shows the variation of storage compliance with temperature for
unfilled FGPs and carbon black filled FGPNCs made of styrene butadiene
rubber matrix and the varied amounts of sulfur and accelerator. At each
and every temperature the storage compliance decreases with increasing
concentrations of sulfur and accelerator. The increment of the sulfur and
accelerator loading enhances the crosslink density that decreases the
storage compliance. But the increased trend of storage compliance with
respect to the temperature is attributed to the decrease of coefficient of
friction between molecules, fracture of weak entanglements etc.
Fig.16 Variation of storage compliance of different layers carrying varied
crosslink density of (a) unfilled FGPCs and (b) 40 wt% carbon black filled
FGPNCs along the thickness of the sheet.
Fig. 17 Storage compliance of much higher crosslink density of (a) unfilled
FGPs and (b) 40 wt% carbon black filled FGPNCs along the thickness of the
sheet
Fig 17 (a) shows the variation of storage compliance with temperature for
much higher crosslink density of unfilled FGPs made of styrene butadiene
rubber matrix. At room temperature, the storage compliance at a distance of
6 mm, where the concentration of sulfur and accelerator is maximum
(350 wt%), is 3 decades lesser than the layer at a distance of 0.4 mm along
the thickness direction, where the concentration of curatives is the least (1
wt%). The values of storage compliance at room temperature at a distance of
6.0 and 0.4 mm are 7.0 x 10-11 and 4 x 10-8 Pa-1 respectively. The values of
storage compliance corresponding to 350 and 200 wt% concentrations at
400 C are 2.58 x 10-10 and 7.8 x 10 -n Pa-i and the plateau compliance
values for the same amounts at 100° C are 5 x 10 -1° and 2.6 x 10-9 pa-i
respectively. Fig. 17(b) shows the change in the storage compliance with
temperature for much higher crosslink density of FGPNCs made of styrene
butadiene rubber matrix, carbon black as a reinforcing agent with particle
size varying in between 20-30 nm and the varied amounts of sulfur and
accelerator. At room temperature, the storage compliance at a distance of
5.5 mm, where the concentration of sulfur and accelerator is maximum (350
wt%), is 2 decades less than the layer at a distance of 0.25 mm along the
thickness direction, where the concentration of curatives is less (1 wt%). The
values of storage compliance at a distance of 5.5 and 0.25 mm are 1.0 x 10-
10 and 1 x lO-8 Pa-1 respectively.
Fig. 18 Variation of complex compliance of different layers carrying varied
crosslink density of (a) unfilled FGPs and (b) 40 wt% carbon black filled
FGPNCs along the thickness of the sheet.
Pig 18 shows the variation of complex compliance with temperature for
unfilled FGPCs and carbon black filled FGPNCs made of varied amounts of
sulfur and accelerator. For low crosslink density levels, Fig. 18 shows the
increasing trend of complex compliance with increasing amounts of sulfur
and accelerator. The complex compliance values corresponding to 0.25 and
3 wt% curatives at room temperature are 1.6 x 10-8 and 4.1 x 10-8 Pa-1
respectively. Fig. 18(b) shows the variation of complex compliance with
temperature for filled FGPNCs with varied amounts of sulfur and accelerator
in SBR matrix. The values of the complex compliance corresponding to 0.25
and 11 wt% (37 x 10-4 mol/cc) curatives at room temperature are 1.2 x 10-8
and 4.2 x 1O9 Pa * respectively. The complex compliance values for the
unfilled FGPCs for the same amount of curatives at room temperature are
2.71 x lO-8 and 1.56 x 10-8 pa-i respectively.
Fig. 19 Complex compliance of much higher crosslink density of (a) unfilled
FGPs and (b) 40 wt% carbon black filled FGPNCs along the thickness of the
sheet.
Fig 19(a) shows that at room temperature, the complex compliance at a
distance of 6 mm, where the concentration of sulfur and accelerator is
maximum (350 wt%), is 3 decades lesser than the layer at a distance of 0.4
mm along the thickness direction, where the concentration of curatives is
the less (1 wt%). The values of complex modulus at a distance of 6.0 and 0.4
mm at room temperature are 7.4 x 10-11 and 4 x 10-8 Pa-1 respectively. Fig.
19(b) shows that at room temperature, the complex compliance at a
distance of 5.5 mm, where the concentration of sulfur and accelerator is
maximum (350 wt%), is 2 decades lesser than the layer at a distance of 0.25
mm along the thickness direction, where the concentration of curatives is
less (0.25 wt%). The values of complex compliance at a distance of 5.5 and
0.25 mm are'1.11 x 10-io and 1.26 x 10-8 pa-i respectively.
EXAMPLES
Example A: 16 gm metal oxide/s, 10 gm acid/s, 10 gm antioxidant/s, 1 to
2100 gm (interval of 10 gm) curing agent/s (variable), 1 to 2100 gm (interval
of 10 gm) accelerator/s (variable), 16 gm processing oil/s and 560 gm nano
sized filler/s are mixed in 600 gm polymer/s at a temperature of 50 to
125°C, mixing time of 10 to 150 minutes and friction ratio of 1:1.1 to 1:1.5
by two roll mixing mill. After uniform mixing of all these chemical
ingredients in to the matrix, a thin sheet of thickness in the range of 0.1 to
10 mm (based on our requirement) is prepared at a temperature of 50 to
125°C, and friction ratio of 1:1.1 to 1:1.5 in a same two roll mixing mill. The
both sides of this thin sheet/s are coated with coating agents sometimes
(not always). The coated/uncoated thin sheet is kept in hydraulic press in
between two teflon sheet and pressed it again to make a very thin sheet of
thickness less than 0.1 mm. The coated/uncoated thin sheets are laminated
to the desired thickness to make a green functionally graded polymers either
increasing or decreasing order of nano particles and/or using template. The
split steel die is preheated before putting these green functionally graded
polyrnerss in it. The preheating is done in a hydraulic press at a
temperature • of 100 to 250oC. After temperature is reached close to the
desired temperature, the green functionally graded polymers are filled in the
die and the other half is placed over it. The temperature of 100 to 250°C and
pressure of 1 to 20 MPa and time of 10 minutes to 8 hours are selected to
get cured functionally graded polymers.
Example B: 22 gm metal oxide/s, 15 gm acid/s, 10 gm antioxidant/s, 10
gm processing oil/s, 1 to 460 gm nano material/s (variable, interval of 10
gm), 25 gm processing oil/s, 50 gm curing agent/s and 50 gm accelerator/s
are mixed in 700 gm polymer/s at a temperature of 50 to 125°C for 10 to
150 minutes and at friction ratio of 1:1.1 to 1:1.5 by two roll mixing mill.
The green functionally graded polymeric nanocomposites are prepared as per
method described in example 1. The green functionally graded polymeric
nanocomposites are filled in the die and the other part of the die is placed
over it at a temperature of 100 to 250°C. The pressure is 1 to 20 MPa. The
temperature and pressure are maintained for 10 minutes to 8 hours. The
cured functionally graded polymeric nanocomposites are taken out from the
mould.
MAJOR ADVANTAGES OF THE PRESENT FGM8/FGPNCS
Advantage 1) The novel functionally graded polymers and its composite can
be used in wider range of temperature.
Advantage 2) It is possible to grade the crosslinking density of the FGMs and
FGPNCs both in increasing and decreasing order from inner surface to outer
surface and from outer surface to inner surface and in radial direction.
Advantage 3) The crosslink density of the unfilled FGPs is increased from 14
x 10-4 to 192 x 10-4 mol/cc when the concentrations of both curing agent(s)
and accelerator(s) are increased from 1 to 350 wt% (with respect to 100
polymer) each along the span of 6 mm thick vulcanizate. The increase in the
crosslink density is 1275 %.
Advantage 4) Storage modulus of FGPs at room temperature increases from
4 x 107 to 1.4 x 101° with increasing crosslink density along the thickness.
The increase in storage modulus is nearly 34900 %.
Advantage 5)' Complex modulus of FGPs at room temperature increases from
4.2 x 107 to 1.47 x 101(> with increasing crosslink density along the
thickness. The increase in storage modulus is nearly 34900 %.
Advantage 6) Storage compliance decreases with crosslink density. For the
variation of curatives from 0 to 350wt%, storage compliance at room
temperature decreases from 4 x 10-8 Pa-i to 7.0 x 10-11 Pa-1 respectively. The
% decrease is -100%.
Advantage 7) Tensile strength of FGPs increases with crosslink density from
1.7 to 2.7 MPa when the wt% levels of curing agent and accelerator are
increased from 1 to 11 wt% along thickness while elongation @ break
decreases from 900 to 100 %. The increase in tensile strength is 60 % while
decrease in elongation is 90 %.
Advantage 8) With increasing crosslink density of FGPs, modulus @ 50 %
increases from 0.52 to 1.48 MPa for the variation of curatives from 1 to 11
wt%. The increase in modulus is 185%. Similarly, modulus @ 100 %
elongation increases by ~ 200 %.
Advantage 9) For 40 wt% carbon black filled FGPNCs, crosslink
density is increased from 17 x 1O4 to 210 x 10-4 mol/cc along the span of
5.5 mm thick vulcanizate. The increase in the crosslink density is 1135 %.
Advantage 10) Storage modulus of FGPNCs at room temperature increases
from 8.5 xlO7 to 1.67 x 1010 Pa with increasing crosslink density along the
thickness. The increase in storage modulus is nearly 19500 %.
Advantage 11) Complex modulus of FGPNCs at room temperature increases
from 9.7 xlO7 to 1.72 x 10*° Pa with increasing crosslink density along the
thickness. The increase in storage modulus is nearly 17600 %.
Advantage 12) Storage compliance of FGPNCs decreases with crosslink
density. For the variation of curatives from 0 to 350 wt%, storage
compliance at room temperature decreases from 1 x 10-& Pa-1 to 1.0 x 10-10
Pa-1 respectively. The % decrease in storage modulus is 100.
Advantage 13) Tensile strength decreases with crosslink density from 16.2 to
11.6 MPa when the wt% of curing agent(s) and accelerator(s) are increased
from 1 to 11 wt% along thickness and elongation @ break also decreases
from 1200 to 115 %. The decrease in tensile strength is 30 % and the drop
in elongation is 90 %.
Advantage 14) With increasing crosslink density of FGPNCs, modulus @ 50
% increases from 1,04 to 4.83 MPa for the variation of curatives from 1 to 11
wt%. The increase in modulus is 365%. Similarly, modulus @ 100 %
elongation increases by ~ 660 %.
COMMERCIAL POTENTIAL
Tires, shoe soles, belts, pulleys, seals, washers, Orings, and gaskets,
flexible tubing for pacemaker leads, vascular grafts, and catheters;
biocompatible coatings and pumping diaphragms, etc
It is to be noted that the formulation of the present invention is susceptible
to modifications, adaptations and changes by those skilled in the art. Such
variant formulations are intended to be within the scope of the present
invention, which is further set forth under the following claims:

WE CLAIM
1. A functionally graded polymers (FGPs) and functionally graded polymer
nanocomposites (FGPNCs) having a gradation of crosslinking density,
comprising of polymer(s) matrix, accelerator (s), curing agent(s),
nanomaterials(s), processing oil(s) and other chemicals i.e.,
antioxidant(s), accelerator, activator(s), etc.
2. A process for preparation of functionally graded polymers (FGPs) and
functionally graded polymer nanocomposites (FGPNCs) having a
gradation of crosslinking density comprising steps of:-
mixing of processing oil(s), nanomaterial(s) and other chemicals in
polymer matrix such as herein described,
preparation of a thin layer out of the mixture thus obtained
followed by lamination of the cut piece to obtain green functionally
graded polymers and/or functionally graded polymer
nanocomposites, and
curing of the green graded sheet in a mould.
3. A process as claimed in claim 2 wherein the mixing is carried out using
two-roll mill at a temperature of 50-125°C for 10-150 minutes wherein
the speed of front roll is 10-34 rpm and friction ratio between front and
rear roll is 1:1.1-1:1.5 to obtain a thin layer of 0.1-10 mm in which the
thin layer and the mould is coated with a coating agent such as silicone
spray, detergent/soap solution, silicone emulsion solution, stearic acid,
polytetrofluoro ethylene, polyvinyl alcohol etc in which the mixing may be
carried out by methods such as internal mixing kneader, intermix and
banbary mixer.
4. A functionally graded polymers (FGPs) and functionally graded polymer
nanocomposites (FGPNCs) having a gradation of crosslinking density and
the process for preparation thereof as claimed in claim 1 or 2 wherein the
antioxidant(s), acid(s), processing oil(s) and metal oxide(s) are 1-10% by
wt. accelerator(s) and curing agent(s) are 1.350% by weight and
nanosized material(s) is 0-80% by weight with respect to 100% by wt. of
the polymer.
5. The FGP and/or FGPNCs as claimed in Claim 1 wherein the polymer
matrix is' selected from the group COMPRISING of natural rubber,
polyisoprene rubber, styrene-butadiene rubber, polybutadiene rubber,
ethylene-p'ropylene rubber, ethylene-propylene diene-monomer rubber,
butyl rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile
rubber, polysulfide rubber, polyacrylic rubber, neoprene rubber, hypalon
rubber, silicone rubber, fluorocarbon rubber, polyurethane rubber,
thermoplastic elastomer, and mixture thereof wherein the polymer matrix
natural rubber is selected from the group COMPRISING of standard
malaysian rubber (SMR) L, SMR CV, SMR WF, SMR GP, SMR LV, SMR 5,
SMR 10, SMR 20, SMR 50, technically specified rubbers (TSR) 5, TSR 10,
TSR 20, TSR 50, technically classified rubber, oil extended natural
rubber, deproteinized natural rubber, peptized natural rubber, skim
natural rubber, superior processing natural rubber, heveaplus MG
rubber, epoxidized natural rubber, thermoplastic natural rubber, and
mixture thereof; the polymer matrix styrene-butadiene rubber is
selected from the group COMPRISING of solution styrene-butadiene
rubber i.e., SBR 2305, SBR 2304, emulsion styrene-butadiene rubber
Le., cold SBR 1500, cold SBR 1502, hot SBR 100, and mixture thereof;
the polymer matrix polybutadiene rubber is selected from the group
COMPRISING of cisamer-01, cisamer!220, BR 9000, BR 9004A, BR
9004B, low molecular weight 1, 3 polybutadiene, and mixture thereof;
the polymer matrix butyl rubber is selected from the group COMPRISING
of IIR-1751, IIR-1751F, IIR-745, Exxon butyl 007, Exxon butyl 065,
Exxon butyl 068, Exxon butyl 165, Exxon butyl 268, Exxon butyl 269,
Exxon butyl 365, polysar butyl 100, polysar butyl 101, polysar butyl
101-3, polysar butyl 301, polysar butyl 402, and mixture thereof; the
polymer matrix ethylene-propylene rubber is selected from the group
COMPRISING of dutral-CO-034, dutral-CO-038, dutral-CO-043, dutral-
CO-054, dutral-CO-058, dutral-CO-059, dutral-CO-055, and mixture
thereof; the polymer matrix ethylene-propylene-diene-monomer rubber is
selected from the group COMPRISING of ethylene-propylenedicyclopentadiene
rubber, ethylene-propylene-ethylidenenorbornene
rubber, ethylene-propylene-1, 4 hexadiene rubber, and mixture thereof;
the polymer matrix halobutyl rubber is selected from the group
COMPRISING of Exxon chlorobutyl 1065, Exxon chlorobutyl 1066, Exxon
chlorobutyl 1068, Polysar chlorobutyl 1240, Polysar chlorobutyl 1255,
Exxon bromobutyl 2222, Exxon bromoburyl 2233, Exxon bromobutyl
2244, Exxon bromobutyl 2255, Polysar bromobutyl X2, Polysar
bromobutyl 2030, and mixture thereof; the polymer matrix nitrile rubber
is selected from the group COMPRISING of Krynac-2750, Nipol-1053,
Nipol-1032, Paracril-C, Chemigum-N-3, Krynac-5075, and mixture
thereof; the polymer matrix hydrogenated nitrile rubber is selected from
the group COMPRISING of zetpol-1010, zetpol-1020, zetpol-2010, zetpol-
2020, and mixture thereof; the polymer matrix polyacrylic rubber is
selected from the group COMPRISING of hycar-4051, hycar-4052, hycar-
4054, vamac-B-124, and mixture thereof; the polymer matrix neoprene
rubber is selected from the group COMPRISING of neoprene-AC,
neoprene-AD, neoprene-ADG, neoprene-AF, neoprene-AG, neoprene-FB,
neoprene-GN, neoprene-GNA, neoprene-GRT, neoprene-GS, neoprene-
GW, neoprene-W, neoprene-W-MI, neoprene-WB, neoprene-WD,
neoprene-WHV, neoprene-WHY-100, neoprene-WHV-200, neoprene-
WHV-A, neoprene-WK, neoprene-WRT, neoprene-WX, neoprene-TW,
neoprene-TW-100, neoprene-TRT, and mixture thereof; the polymer
matrix hypalon rubber is selected from the group COMPRISING of
hypalon-20, hypalon-30, hypalon-LD-999, hypalon-40S, hypalon-40,
hypakm-4085, hypalon-623, hypalon-45, hypalon-48S, hypalon-48, and
mixture thereof; the polymer matrix silicone rubber is selected from the
group COMPRISING of silicone MQ, silicone MPQ, silicone MPVQ, silicone
FVQ, and mixture thereof; the polymer matrix fluorocarbon rubber is
selected from the group COMPRISING of viton-LM, viton-C-10, viton-A-
35, viton-A, viton-A-HF, viton-E-45, viton-E-60, viton-E-60C, viton-
E403, viton-B-50, viton-B, viton-B-70, viton-910, viton-GLT, viton-
GF, viton-VTR-4730, DAI-EL-G-101, DAI-EL-701, DAI-EL-751, DAI-EL-
702, DAI-EL-704, DAI-EL-755, DAI-EL-201, DAI-EL-501, DAI-EL-801,
DAI-EL-901, DAI-EL-902, tecnoflon-FOR-LHF, tecnoflon-NMLB,
tecnoflon-NML, tecnoflon-NMB, tecnoflon-NM, tecnoflon-NH,
tecnoflon-FOR-45-45BI, tecnoflon-FOR-70-70BI, tecnoflon-FOR-45-C-CI,
tecnoflon-FOR-60K-KI, tecnoflon-FOR-50E, tecnoflon-TH, tecnoflon-TN-
50, tecnoflon-TN, tecnonon-FOR-THF, tecnoflon-FOR-TF-50, tecnoflon-
FOR-TF, fluorel-2145, fluorel-FC-2175, nuorel-FC-2230, fluorel-FC-2178,
fluorel-FC-2170, fluorel-FC-2173, fluorel-FC-2174, fluorel-FC-2177,
fluorel-FC-2176, fluorel-FC-2180, fluorel-FC-81, nuorel-FC-79, fluorel-
2152, fluorel-FC-2182, fluorel-FC-2460, fluorel-FC-2690, fluorel-FC-
2480, and mixture thereof, the polymer matrix polyurethane rubber
(polyether and polyester type) is selected from the group COMPRISING of
FMSC-1035, FMSC-1035T, FMSC-1040, FMSC-1050, FMSC-1060,
FMSC-1066, FMSC-1070, FMSC-1075, FMSC-1080-SLOW, FMSC-1080-
FAST, FMSC-1085, FMSC-1090-FAST, FMSC-1090-SLOW, and mixture
thereof; the polymer matrix thermoplastic elastomer (polyurethane,
polyester, polyamide, styrene-butadiene-styrene, blends, etc) is selected
from the group COMPRISING of SBS 1401, SBS 4402, SBS 4452, SBS
1301, SBS 1401-1, SBS 4303, estane-55103, hytrel-40xy, hytrel-63xy,
hytrel-72xy, gaflex-547, pebax-2533, pebax-6333, TPR-1600, TPR-1900,
TPR-2800, TELCAR-340, SOMEL-301, SOMEL-601, santoprene, cariflex-
TR, solprene-400, stereon, and mixture thereof; the polymer matrix
polysulfide elastomer is selected from the group COMPRISING of thiakol-
A, thiakol-B, thiakol-FA, thiakol-ST, and mixture thereof.
6. The FGP and/or FGPNCs as claimed in Claim 5 wherein the polymer
matrix natural rubber is cured by vulcanizing agent selected from the
group COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, diurethane, and mixture thereof which is in the range
of 1 to 350 wt% (with respect to 100 polymer); the polymer matrix
styrene-butadiene rubber is cured by vulcanizing agent selected from the
group COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, diurethane, and mixture thereof which is in the range
of 1 to 350 wt% (with respect to 100 polymer); the polymer matrix
polybutadiene rubber is cured by vulcanizing agent selected from the
group COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, diurethane, and mixture thereof which is in the range
of 1 to 350 wt% (with respect to 100 polymer); the polymer matrix butyl
rubber is cured by vulcanizing agent selected from the group
COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide, benzoyl
peroxide, diurethane, p-quinone dioxime, p-quinone dioxime dibenzoate,
phenol-formaldehyde resin, and mixture thereof which is in the range of
1 to 350 wt% (with respect to 100 polymer); the polymer matrix ethylenepropylene
rubber is cured by vulcanizing agent selected from the group
COMPRISING of hydrogen peroxide, dicumyl peroxide, benzoyl peroxide,
di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy) hexane, bis(2,4-
dichloro-benzoyl) peroxide, and mixture thereof which is in the range of 1
to 350 wt% (with respect to 100 polymer); the polymer matrix ethylenepropylene-
diene-monomer rubber is cured by vulcanizing agent selected
from the group COMPRISING of sulphur, hydrogen peroxide, dicumyl
peroxide, benzoyl peroxide, diurethane, and mixture thereof which is in
the range of 1 to 350 wt% (with respect to 100 polymer); the polymer
matrix halobutyl rubber is cured by vulcanizing agent selected from the
group COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, zinc oxide, p- quinone dioxime, p-quinone dioxime
dibenzoate, phenol-formaldehyde resin, amine, and mixture thereof
which is in the range of 1 to 350 wt% (with respect to 100 polymer); the
polymer matrix nitrile rubber is cured by vulcanizing agent selected from
the group COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, and mixture thereof which is in the range of 1 to 350
wt% (with respect to 100 polymer); the polymer matrix hydrogenated
nitrile rubber is cured by vulcanizing agent selected from the group
COMPRISING of sulphur, hydrogen peroxide, dicumyl peroxide, benzoyl
peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy)
hexane, bis(2,4-dichloro-benzoyl) peroxide, tertiary butyl perbenzoate,
and mixture thereof which is in the range of 1 to 350 wt% (with respect to
100 polymer); the polymer matrix polyacrylic rubber is cured by
vulcanizing agent selected from the group COMPRISING of amine,
diamine, activated thiol, sulphur, thiourea, trithiocyanuric acid,
hydrogen peroxide, dicumyl peroxide, benzoyl peroxide, and mixture
thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix neoprene rubber is cured by vulcanizing
agent selected from the group COMPRISING of magnesium oxide, zinc
oxide, lead oxide, iron oxide, titanium oxide, amine, phenol, sulfenamide,
thiazoles, thiuram, thiourea, guanidine, and mixture thereof which is in
the range of 1 to 350 wt% (with respect to 100 polymer); the polymer
matrix hypalon rubber is cured by vulcanizing agent selected from the
group COMPRISING of magnesium oxide, zinc oxide, lead oxide, iron
oxide, titanium oxide, sulphur, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, N,N'-m-phenylenedimaleimide, amine, phenol,
sulfenamide, thiazoles, thiuram, thiourea, guanidine, and mixture
thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix silicone rubber is cured by vulcanizing
agent selected from the group COMPRISING of hydrogen peroxide,
dicumyl peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-
bis (t-butyl peroxy) hexane, bis(2,4-dichloro-benzoyl) peroxide, tertiary
butyl perbenzoate, and mixture thereof which is in the range of 1 to 350
wt% (with respect to 100 polymer); the polymer matrix fluorocarbon
rubber is cured by vulcanizing agent selected from the group
COMPRISING of hydrogen peroxide, dicumyl peroxide, benzoyl peroxide,
di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl peroxy) hexane, bis(2,4-
dichloro-benzoyl) peroxide, tertiary butyl perbenzoate,
hexamethylenediamine carbamate, bis(cinnamylidene)
hexamethylenediamine, hydroquinone, 4-4'-isopropylidene bisphenol or
mixture thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix polyurethane rubber (polyether and
polyester type) is cured by vulcanizing agent selected from the group
COMPRISING of 1,4-butanediol, 1,4-cyclohexanedimethanol, l,4-bis(2-
hydroxyethoxy) benzene, 4,4'methylene-bis(2-chloroaniline), and mixture
thereof which is in the range of 1 to 350 wt% (with respect to 100
polymer); the polymer matrix thermoplastic elastomer (polyurethane,
polyester, polyamide, styrene-butadiene-styrene, blends, etc) is cured by
vulcanizing agent selected from the group COMPRISING of lead oxide,
cadmium oxide, zinchydroxide, hydrogen peroxide, dicumyl peroxide,
benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butyl
peroxy) hexane, bis(2,4-dichloro- benzoyl) peroxide, tertiary butyl
perbenzoate, and mixture thereof which is in the range of 1 to 350 wt%
(with respect to 100 polymer); and the polymer matrix polysulfide
elastomer is cured by vulcanizing agent selected from the group
COMPRISING of lead oxide, cadmium oxide, zinchydroxide, hydrogen
peroxide, dicumyl peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-
dimethyl-2,5-bis (t-butyl peroxy) hexane, bis(2,4-dichloro-benzoyl)
peroxide, tertiary butyl perbenzoate, hexamethylenediamine carbamate,
bis(cinnamylidene) hexamethylenediamine, hydroquinone, 4-4'-
isopropylidene bisphenol, and mixture thereof which is in the range of 1
to 350 wt% (with respect to 100 polymer)
7. The FGPs and FGPNCs as claimed in Claim 1 wherein the curing of
polymer matrix COMPRISING of either natural rubber, polyisoprene
rubber, styrene-butadiene rubber, polybutadiene rubber, ethylenepropylene
rubber, ethylene-propylene diene monomer rubber, butyl
rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile rubber,
polysulfide elastomer, polyacrylic rubber, neoprene rubber, hypalon
rubber, silicone rubber, fluorocarbon rubber, polyurethane rubber,
thermoplastic elastomer and/or mixture thereof is further accelerated by
accelerator selected from the group COMPRISING of tertbuttylbenzthiazyl
sulphonamide, benzthiazyl 2-sulphenmorpholide,
dicyclohexyl benzthiazyl sulphonamide, N-cyclohexyl-2-benzothiazole
sulfenamide, 2-mercaptobenzothiazole, 2,2'dibenzothiazyl disulfide,
tetramethylthiuram disulfide, zinc dimethyldithiocarbamate, zinc
dibutyldithiocarbamate, 4,4'dithiodimorpholine, tellurium
diethyldithiocarbamate, dipentamethylene thiuramhexasulfide,
tetramethylthiuram monosulfide, ferricdimethyldithiocarbamate, zinc
mercaptobenzthiazole, zinc 0,0 dibutylphosphorodithioate, zinc
diethyldithiocarbamate, 4-4'dithio dimorpholine, which is in the range of
1 to 350 wt% (with respect to 100 polymer) and , and mixture thereof in a
ratio of 1 : 9 to 9:1 (by weight) wherein the curing of polymer matrix
COMPRISING of either natural rubber, polyisoprene rubber, styrenebutadiene
rubber, polybutadiene rubber, ethylene-propylene rubber,
ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylic rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer
and/or mixture thereof is further accelerated by accelerator activator
selected from the group COMPRISING of metal oxide and acid which is in
the range of 10:1 to 1:10 wt% (with respect to 100 polymer).
8. The FGPNCs as claimed in Claim 1 wherein the polymer matrix
COMPRISING of either natural rubber, polyisoprene rubber, styrenebutadiene
rubber, polybutadiene rubber, ethylene-propylene rubber,
ethylene-propylene diene monomer rubber, butyl rubber, halobutyl
rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide elastomer,
polyacrylie rubber, neoprene rubber, hypalon rubber, silicone rubber,
fluorocarbon rubber, polyurethane rubber, thermoplastic elastomer
and/or mixture thereof is graded by carbon nanoparticles selected from
the group COMPRISING of N-110, N-115, N-120, N-121, N-125, N-134,
N-135, N-212, N-220, N-231, N-234, N-293, N-299, N-315, N-326, N-330,
N-335, N-339, N-343, N-347, N-351, N-356, N-358, N-375, N-539, N-550,
N-582, N-630, N-642, N-650, N- 660, N-683, N-754, N-762, N-765, N-
772, N-774, N-787, N-907, N-908, N-990, N-991, and mixture thereof
which is in the range of 0 to 80 wt% (with respect to 100 polymer)
wherein the polymer matrix COMPRISING of either natural rubber,
polyisoprene rubber, styrene-butadiene rubber, polybutadiene rubber,
ethylene-propylene rubber, ethylene-propylene diene monomer rubber,
butyl rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile
rubber, polysulfide elastomer, polyacrylic rubber, neoprene rubber,
hypalon rubber, silicone rubber, fluorocarbon rubber, polyurethane
rubber, thermoplastic elastomer and/or mixture thereof is further graded
by various silica nanoparticles i.e., precipitated silica (i.e., HS-200, HS-
500, HS-700, etc), fumed silica and mixture thereof which is in the range
of 0 to 80 wt% (with respect to 100 polymer) wherein the polymer
matrix COMPRISING of either natural rubber, polyisoprene rubber,
styrene-butadiene rubber, polybutadiene rubber, ethylene-propylene
rubber, ethylene-propylene diene monomer rubber, butyl rubber,
halobutyl rubber, nitrile rubber, hydrogenated nitrile rubber, polysulfide
elastomer, polyacrylic rubber, neoprene rubber, hypalon rubber, silicone
rubber, fluorocarbon rubber, polyurethane rubber, thermoplastic
elastomer and/or mixture thereof is further graded by clay nanoparticles
which is in the range of 0 to 80 wt% (with respect to 100 polymer)
wherein the polymer matrix COMPRISING of either natural rubber,
polyisoprene rubber, styrene-butadiene rubber, polybutadiene rubber,
ethylene-propylene rubber, ethylene-propylene diene monomer rubber,
butyl rubber, halobutyl rubber, nitrile rubber, hydrogenated nitrile
rubber, polysulfide elastomer, polyacrylic rubber, neoprene rubber,
hypalon rubber, silicone rubber, fluorocarbon rubber, polyurethane
rubber, thermoplastic elastomer and/or mixture thereof is further graded
by mixed carbon nanoparticles, nanosilica and nanoclay in a volume
ratio of 5:2:1 to 1:2:5 selected from the group COMPRISING of N-110, N-
115, N-120, N-121, N-125, N-134, N-135, N-212, N-220, N-231, N-234,
N-293, N-299, N-315, N-326, N-330, N-335, N-339, N-343, N-347, N-351,
N-356, N-358, N-375, N-539, N-550, N-582, N-630, N-642, N-650, N-660,
N-683, N-754, N-762, N-765, N-772, N-774, N-787, N-907, N-908, N-990,
N-991, precipitated silica (i.e., HS-200, HS-500, HS-700, etc), fumed
silica, clay and mixture thereof wherein the polymer matrix COMPRISING
of either natural rubber, polyisoprene rubber, styrene-butadiene rubber,
polybutadiene rubber, ethylene-propylene rubber, ethylene-propylene
diene monomer rubber, butyl rubber, halobutyl rubber, nitrile rubber,
hydrogenated nitrile rubber, polysulfide elastomer, polyacrylic rubber,
neoprene rubber, hypalon rubber, silicone rubber, fluorocarbon rubber,
polyurethane rubber, thermoplastic elastomer and/or mixture thereof is
further graded by mixed carbon nanoparticles having same concentration
gradient but different particle size i.e 5 to 85 nm and selected from the
group COMPRISING of N-110, N-115, N-120, N-121, N-125, N-134, N-
135, N-212, N-220, N-231, N-234, N-293, N-299, N-315, N-326, N-330,
N-335, N-339, N-343, N-347, N-351, N-356, N-358, N-375, N-539, N-550,
N-582, N-630, N-642, N-650, N-660, N-683, N-754, N-762, N-765, N-772,
N-774, N-787, N-907, N-908, N-990, N-991.
9. The metal oxide used in accelerator activator as claimed in Claim 7 is
selected from the group COMPRISING of zinc oxide, lead oxide, calcium
oxide, magnesium oxide, lead oxide, etc which is in the range of 1
to 10 wt% (with respect to 100 polymer) and the acid used in accelerator
activator is selected from the group COMPRISING of stearic acid, palmitic
acid, oleic acid, etc which is in the range of 1 to 10 wt% (with respect to
100 polymer).
10. The FGPs and FGPNCs as claimed in Claim 1 further comprises an
antioxidant selected from the group COMPRISING of condensation
product of acetone and diphenyl-amine, phenyl-beta-napthylamine,
blends of diphenyl-p-phenylene diamine and selected arylamine
derivatives, blend of arylamines, polymerized 1,2 dihydro 2,2,4-trimethyl
quinoline, N-( 1,3-dimethylbutyl)-N'-phenyl-p-phenylene-diamine, diaryl
para phenylene diamines, 2 mercaptobenzimidazole, and mixture thereof
which is in the range of 1 to 10 wt% (with respect to 100 polymer) and a
process oil is selected from the group COMPRISING of paraffinic oil,
naphthenic oil, aromatic oil, vegetable oil, and mixture thereof which is in
the range .of 1 to 10 wt% (with respect to 100 polymer).