Appendix 1
Calculation of Stoichiometric Weight of Curing Agent
Epoxy Equivalent Weight (EEW)
Epoxy Equivalent Weight (EEW) is a ratio of the weight of a polymer
molecule (molecular weight) to its number of epoxy groups. Since molecular weight
is a very small quantity, we express it in terms of “mole”. All substances will have
6.023 x 1023 molecules in a mole.
Weight of a polymer molecule
EEW =
g / mol
(1)
Number of epoxy groups in that polymer molecule
When EEW is expressed in terms of mole, it becomes,
EEW =
Weight of a polymer molecule
Number of epoxy groups in that polymer molecule
6.023×1023g/mol
(2)
Similarly, Amine Hydrogen Equivalent Weight (AHEW) in terms of mole is,
AHEW =
Weight of a curing agent moleculepolymer molecule
×6.023×1023g/mol (3)
Number of hydrogen groups in that molecule
To maintain stoichiometric equivalency (proper cross-linking), the number of
moles of epoxy should be same as the number of moles of curing agent.
Calculation of stoichiometric weight of curing agent
Single epoxy resin system
Let, weight of epoxy resin = wm1 g, weight of curing agent = wcu g,
EEW of epoxy resin = EEWm1 g/mol, AHEW of curing agent = AHEWcu g/mol
To maintain stoichiometric equivalency (proper cross-linking), the number of
moles of epoxy should be same as the number of moles of curing agent.
Therefore,
Wcu
Wm1
(4)
EEWm1 AHEWcu
When WE, EEWE and AHEWC are known, the weight of curing agent required
can be calculated from the equation,
AHEWcu
Wcu=
wm1
(5)
EEWm1
226
Appendix 2
Calculation of Volume fraction of nanofillers
In this analysis, four constituents are considered. Properties of these materials
are represented by subscripts: f for filler, m1 for matrix1, m2 for matrix2 and cu for
curing agent.
Let,
Vc = volume of composite, Vf = volume of filler, Vm1 = volume of matrix1, Vm2 =
volume of matrix2, Vcu = volume of curing agent, c=density of composite, f =
density of filler, m1 = density of matrix1, m2 = density of matrix2, cu = density of
curing agent, Wf = weight fraction of filler, Wm1 = weight fraction of matrix1,Wm2 =
weight fraction of matrix2, Wcu = weight fraction of curing agent, Vf = volume
fraction of filler, Vm1 = volume fraction of matrix1, Vm2 = volume fraction of matrix2
and Vcu= volume fraction of curing agent.
The volume of composite is defined as the sum of the volume of four
constituents - filler, matrix1, matrix2 and curing agent.
vc = vf + v m1 + v m2 + vcu
(1)
Equation 1 can be rewritten as,
wc wf
w
w
w
=
+ m1 + m2 + cu
ρc ρf
ρ m1
ρ m2
ρcu
(2)
Dividing equation 2 by wc,
w cu
wf
w m1
w m2
1
=
+
+
+
ρ w cρf
w cρ m1
w cρ m2
w cu ρcu
(3)
Now,
Wf =
wf
w m1
is the weight fraction of filler, Wm1 =
is the weight fraction
wc
wc
of matrix1.
Wm2 =
w cu
w m2
is the weight fraction of matrix2 and Wcu =
is the weight
wc
wc
fraction of curing agent.
Therefore, the density of the composite is,
c
=
1
Wf
Wm1
m1
f
Wm 2
Wcu
m2
(4)
cu
The volume fraction of filler is defined as the ratio of volume of filler to the
volume of composite. This is represented as,
Vf
vf
vc
Equation 5 can be written as,
vf
Vf
vc
(5)
wf /
wc /
f
(6)
f
227
Since, Wf
wf
, equation 6 becomes,
wc
Vf
Wf
c
(7)
f
Knowing the weight fraction of filler in the composite (Wf), density of filler
(ρf) and the density of composite (ρc) as calculated from equation 4, the volume
fraction of filler in the composite can be calculated from equation 7.
Designation of fabricated nanocomposite samples ID in the present research
work
Sample
epoxy
epoxy - SiO2
epoxy - Al2O3
epoxy - ZnO
Designation
epoxy/0 wt.%
epoxy-5 wt.% SiO2
epoxy-10 wt.% SiO2
epoxy-15wt.% SiO2
epoxy-20wt.% SiO2
epoxy-5 wt.% Al2O3
epoxy-10 wt.% Al2O3
epoxy-15wt.% Al2O3
epoxy-20wt.% Al2O3
epoxy-5 wt.% ZnO
epoxy-10 wt.% ZnO
epoxy-15 wt.% ZnO
Nanofiller
5%
10%
15%
20%
5%
10%
15%
20%
5%
10%
15%
Filler size
21nm
21nm
21nm
21nm
21nm
30-45nm
30-45nm
30-45nm
30-45nm
30-45nm
30-45nm
228
Appendix 3
List of Acronyms
ζac
Ea
ATH
AlN
Al2O3
ASTM
AHEW
NH4Cl
A
AFM
BN
BaTiO3
BST
BTDA
C
CO
cm
CTE
CTI
G
XLPE
ρdc
dB
ρ
DES
DSC
DGEBA
DA
DM
tanδ
DMONT
DMA
EP
EDAX
EEW
ESHR
ac conductivity
Activation energy
Alumina trihydrate
Aluminium nitride
Aluminium oxide or alumina
American society for testing and materials
Amine hydrogen equivalent weight
Ammonium chloride
Ampere(s)
Angular frequency
Atomic force microscopy
Boron nitride
Barium titanate
Barium strontium titanate
Benzophenonetetracarboxylic acid dianhydride
Capacitance
Carbon monoxide
Centimeter(s)
Co-efficient of thermal expansion
Comparative tracking index
Conductivity
Conductance
Cross-linked polyethylene
dc electrical resistivity
Decibel(s)
Density
Dielectric constant
Dielectric strength
Differential scanning calorimeter
Diglycidylether of bisphenol A
Dimensional analysis
Direct mixing
Dissipation factor or loss tangent
Dodecyl-montmorillonite
Dynamic mechanical analysis
Electrode polarization
Energy dispersive X-ray
Epoxy equivalent weight
Epoxy silica hybrid resins
229
EPR
EPDM
EVA
E-Ion1.150
FEA
FTIR
f
FDS
FS
GaN
GPa
Tg
HDT
Hz
HTV
h
-OH
″
Z
IPT
IGBT
IVM
LMD
PZT
LC
LDPE
LFD
E"
MQT
MgO
MA
MLE
MPa
m
m
mm
min
MMT
AEAPS
nm
N
Ω
Ethylene propylene rubber
Ethylene propylene diene monomer
Ethyl vinyl acetate
Na-ionic-graft-copolymer
Finite element analysis
Fourier transform infrared spectroscopy
Frequency
Frequency domain spectroscopy
Fumed silica
Gallium nitride
Giga Pascal
Glass transition temperature
Heat deflection temperature
Hertz
High temperature vulcanized
Hours
Hydroxyl groups
Imaginary dielectric constant
Impedance
Inclined plane tracking
Insulated gate bipolar transistor
Interface volume model
Langmuir-type model for diffusion
Lead zirconate titanate
Leakage current
Linear density polyethylene
Low frequency dispersion
Loss modulus
Macroscopic quantum tunneling
Magnesium oxide
Maleic anhydride
Maximum likelihood estimation
Mega Pascal
Meter(s)
Micrometer(s)
Millimeter(s)
Minute(s)
Mobility
Montmorillonite
N-(2-aminoethyl)3-aminopropyl-trimethoxysilane
Nanometer(s)
Newton
Ohm(s)
230
OTMS
SPN
oMMT
OMLS
o-Ps
PD
phr
ε0
PA
PLA
PBT
PE
PMMA
PP
PS
PALS
PDC
PC
PDMS
PET
PEO
PVDF
PVA
PVP
PTFE
KBr
PMDA
o
QDC
RF
'
RH
rpm
RTV
η
s
S
SEM
Si-OH
Octyltrimethoxysilane
Oligo(oxypropylene) diethyl methyl ammonium chloride
Organomodified montmorillonite
Organically modified layered silicate
Ortho-positronium
Partial discharge
Parts per hundred gram
Permittivity of vacuum
Phase angle
Polyamide resin
Polyactide
Poly butylene terephthalate
Polyethylene
Poly methyl methacrylate
Polypropylene
Polystyrene
Positron annihilation lifetime spectrometer
Polarization and depolarization current
Polycarbonate
Polydimethylsiloxane
Polyethylene terephthalate
Poly (ethylene oxide)
Poly vinylidene fluoride
Poly vinyl alcohol
Poly (vinyl pyrrolidone)
Poly tetra fluoro ethylene
Potassium bromide
Pyromelliticdianhydride
Pre-exponential factor
Quasi - direct conduction
Radio frequency
Real dielectric constant
Relaxation time
Relative humidity
Revolutions per minute
Room temperature vulcanized
Scale parameter
Second(s)
Siemens
Scanning electron microscopy
Shape parameter
Silanol groups
231
SiO2
SiC
SiR
Ks
E´
s
Shore D
s
T
TGA
TMA
TSC
TiO2
TI
TR
TEM
TETA
UTM
USB
VMT
V
ζV
Vf
ρV
Wf
H2O
WAXD
XRD
ZnO
Silicon dioxide or silica
Silicon carbide
Silicone rubber
Specific wear rate
Storage modulus
Surface conductivity
Surface hardness
Surface resistivity
Temperature
Thermal conductivity
Thermal gravimetric analysis
Thermal mechanical analysis
Thermally stimulated current
Titanium dioxide
Tracking index
Tracking resistance
Transmission electron microscope
Tri-ethylene-tetra-amine
Universal testing machine
Universal serial bus
Vermiculite
Volts
Volume conductivity
Volume fraction
Volume resistivity
Weight fraction
Water
Wide-angle-x-ray diffractometer
X-ray diffraction
Zinc oxide
232
Appendix 4
Research publications
International journals/ National journal/ International conferences/
National conferences
1. M.G. Veena, N.M. Renukappa, J.M. Raj, C. Ranganathaiah, K.N. Shivakumar,
“Characterization of Nano-Silica Filled Epoxy composites for Electrical and
Insulating Applications”, Journal of Applied Polymer Science, Vol.21(5),
pp.2752-2760, 2011.
2. M.G. Veena, N.M. Renukappa, B. Suresha, K.N. Shivakumar, “Tribological
and Electrical Properties of Silica-Filled Epoxy Nanocomposites”, Polymer
Composites, Vol.32 (12), pp. 2038-2050, 2011.
3. M.G. Veena, Kunigal N. Shivakumar, N.M. Renukappa, B. Suresha,
“Influence of SiO2 content in epoxy-SiO2 nanocomposites on mechanical and
electrical resistivity behavior”, American Institute of Physics, Conference
Proceedings, Vol.1276, pp.219-226, 2010.
4. M.G. Veena, N.M. Renukappa, S. Seetharamu, P. Sampathkumaran, “Effect of
nanofiller at low frequency behavior of dielectric insulator”, IEEE
Proceedings (ICPADM), pp. 745-748, 2009.
5. M.G. Veena, N.M. Renukappa, Siddaramaiah, R.D. Sudhakersamuel,
“Electrical conducting behavior of hybrid nanocomposites containing
polyaniline, carbon nanotube and carbon black”, SPIE Proceedings, Vol.7267,
pp. 1-6, 2008.
6. M.G. Veena, N.M. Renukappa, P. B. Chethan, C. Ranganathaiah, “Evaluation
of Dielectric Properties of epoxy nanocomposites by NDT Approach”, Journal
of material science: materials in electronics (submitted), 2012.
7. M.G. Veena, N.M. Renukappa, P. B. Chethan, Siddaramaiah, K.N.
Shivakumar, “Effect of seawater ageing on dielectric properties of epoxy
nanocomposites”, Journal of materials and design., (submitted), 2012.
8. M.G. Veena, N.M. Renukappa, K.N. Shivakumar, S. Seetharamu, “Study of
interface behavior on dielectric properties of epoxy-silica nanocomposites”,
IEEE Proceedings (ICPADM), pp. 72-76, 2012.
9. N.M. Renukappa, M.G. Veena, Kunigal N. Shivakumar , B. Suresha, J.
Sundara Rajan, “Effect of addition of Nanopox F400 filler on Thermomechanical Properties of Epoxy Nanocomposites” IEEE International
Conference on Solid Dielectrics, Bologna, Italy, July 1-4, 2013 (Accepted).
10. M.G. Veena, N.M. Renukappa, P.B. Chethan, Rashmi, “Effect of seawater
absorption on surface degradation of epoxy-alumina nanodielectrics for
outdoor insulation applications” International Conference on Recent Advances
in Materials Processing Technology, 2013.
11. M.G. Veena, N.M. Renukappa, J. Sundara Rajan, “Effect of Filler on Arc,
Tracking Resistance and Dielectric Strength of Epoxy-Silica
233
Nanocomposites”, Second International Conference on Materials for the
Future, 2011.
12. M.G. Veena, N.M. Renukappa, K.N. Shivakumar, S. Seetharamu, “Dielectric
properties of nanosilica filled epoxy nanocomposites”, International
Conference on Composites in Future Trends, pp. 65, 2011.
13. M.G. Veena, N.M. Renukappa, Kunigal N. Shivakumar, “Study of Thermal
and Dynamic Mechanical properties of Nanopox F400/SC79 epoxy
composites”,
International
Conference
on
Advanced
Materials,
Manufacturing, Management, and Thermal Sciences, 2010.
14. M.G. Veena, Kunigal N. Shivakumar, N.M. Renukappa, Gowthaman
Swaminathan, “Dielectric properties and Breakdown strength of uniformly
dispersed Nanosilica/Epoxy nanocomposites”, International Conference on
Electro ceramics, pp. 347, 2009.
15. M.G. Veena, B. Suresha , R.M. Devarajaiah, Kunigal N. Shivakumar “Effect
of silica sand and quartz abrasives on three-body abrasive wear behavior of
SiO2 filled epoxy nanocomposites”, International symposium on National
Metallurgist Day - Annual Technical Meeting, 2009.
16. M.G. Veena, N.M. Renukappa, Siddaramaiah “Studies on impedance and
susceptance behavior of insulator-conductor composites”, International
Conference on Recent Advances in Materials, Processing and Technology, pp.
184-188, 2009.
17. M.G. Veena, N.M. Renukappa, Kunigal N. Shivakumar, S. Seetharamu,
“Dielectric properties of nanosilica filled epoxy nanocomposites”, Indian
Academy of Sciences, (Under review), 2012.
18. M.G. Veena, N.M. Renukappa, “Impedance and dielectric Strength of Silica
Filled Epoxy Nanocomposites for Electrical Insulation”, 5th National
Conference on Plastic and Rubber Technology, 2011.
19. M.G. Veena, N.M. Renukappa, “Impedance Property and Morphology of
Silica Filled Epoxy Nanocomposites”, Workshop and National Conference on
Monte Carlo Simulation, at School of Physics, 2010.
20. M.G. Veena, N.M. Renukappa, “An effect of resistivity behavior on epoxySiO2 nanocomposites”, National Conference on NANO-CRYSTAL-2009, pp.
82, 2009.
234