2. This project will be carried out in two stages, first is to
establish the high concentration dispersion of hexagonal
boron nitride and graphene using the suitable surfactant.
And second is to use this high concentration dispersion of
hexagonal boron nitride for the preparation of epoxy
nanocomposites.
The hexagonal boron nitride dispersion and its
nanocomposites will be characterized using various
characterization techniques such as UV-Vis-NIR
spectroscopy, FTIR spectroscopy, tensile testing, SEM and
TEM studies.
To develop the graphene and boron nitride filled polymer
nanocomposites with higher thermal conductivity for
electronic packaging applications.
4. Hexagonal boron nitride is emerged as superior reinforcing
filler for thermal management applications.
Simililary, graphene also exhibit the highest thermal
conductivity measured so far.
The challenge is that overcome the aggregate formation of
hexagonal boron nitride and graphene in the polymer matrix
due to the strong Vander waals forces of attraction between
the hexagonal boron nitride sheets and graphene.
In this regard, surfactant assisted dispersion strategy will be
adopted to overcome the problem of aggregation of hexagonal
boron nitride as well as graphene in epoxy nanocomposites.
5. COMPOSITE MATERIALSComposite material is a material composed of two or more distinct phases
(matrix phase and dispersed phase (filler)) and having bulk properties
significantly different form those of any of the constituents.
Matrix phase
The primary phase, having a continuous character, is called matrix. Matrix
is usually more ductile and less hard phase.
The functions and requirements of the matrix are to:
Keep the fibers in place in the structure;
Help to distribute or transfer loads;
Protect the filaments, both in the structure and before and during
fabrication;
Control the electrical and chemical properties of the composite;
Carry interlaminar shear.
6. Dispersed (reinforcing) phase
The second phase (or phases) is embedded in the matrix in a discontinuous form. This
secondary phase is called dispersed phase. Dispersed phase is usually stronger than
the matrix, therefore it is sometimes called reinforcing phase.
The needs or desired properties of the matrix that depend on the purpose of the structure
are:
Minimize moisture absorption and have low shrinkage;
Low coefficient of thermal expansion;
Must flow to penetrate the fiber bundles completely and eliminate voids during the
compacting/curing process; have reasonable strength, modulus and elongation (elongation
should be greater than fiber);
Must be elastic to transfer load to fibers;
Have strength at elevated temperature (depending on application);
Have low temperature capability (depending on application);
Have excellent chemical resistance (depending on application);
Be easily processable into the final composite shape;
Have dimensional stability (maintain its shape).
7. Boron nitride nanoplatelets for epoxy composites with improved
thermal properties
(a) Thermal conductivity of the
neat epoxy and epoxy
composites as a function of test
temperature
(b) Thermal conductivity and thermal
conductivity enhancement of the neat
epoxy and its composites at 100 C.
J. Yu et al. / Polymer 53 (2012)
471e480
8. Exfoliated hexagonal boron nitride-based polymer nanocomposite
with enhanced thermal conductivity for electronic encapsulation
(a) TEM images of h-BN naonsheets, (b) single/few layer h-BN nanosheets and (c) thick hBN sheets. All the scale bars are 100 nm.
Thermal enhancement factors of h-BN
nanosheet based composites and
h-BN control based nanocomposites
Z. Lin et al. / Composites Science and Technology 90 (2014) 123–128
9. Scanning electron microscope images
of BN nanoplatelets.
High resolution TEM images of BN
nanoplatelets
H. Ulus et al. / Applied Surface Science xxx (2014) xxx– xxx
10. Preparation process of the epoxy composites.
Elasticity Modulus charts
of epoxy nanocomposites
with different nanoparticle loadings.
H. Ulus et al. / Applied Surface Science xxx (2014) xxx– xxx
11. 10 mg of graphene + 10 mg of exfoliated
boron nitride mixed in different PVP solution.
This solution ultrasonicated for 15 minutes
then solution is tested in UV-Vis-NIR (ultraviolet (uv), visible (vis) and near infra-red (nir)
radiation).
Spectra of exfoliated graphene and hexagonal
boron nitride caputured in graph shown next
bellow.
12. Results and discussion
0.6
0.5
Absorance (a.u.)
10 mg graphene + 10 mg of
hexagonal boron nitride
and PVP solution has
been prepared. This
solution ultrasonicated for
15 minutes then solution is
tested in UV-Vis-NIR.
Spectra of exfoliated
graphene and hexagonal
boron nitride caputured in
graph shown above. In the
graph 1st top peak point
shows present of boron
nitride and 2nd peak point
shows the presence of
graphene oxide. As
wavelength increases
absorption decreases.
0.4
0.3
0.2
200
400
600
800
Wavelength (nm)
Figure 1: UV-Vis-NIR spectra of exfoliated graphene and hexagonal boron nitride
13. 0.35
Result and discussion
Absorption (a.u.)
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0.00
0.25
0.50
0.75
1.00
PVA concentration (wt%)
Figure 2: UV-Vis-NIR spectra of PVA assisted dispersion of
graphene and exfoliate boron nitride
14. Conclusion
The hexagonal boron nitride dispersion and its nanocomposites will be
characterized using various characterization techniques such as UV-VisNIR spectroscopy, FTIR spectroscopy, tensile testing, SEM and TEM
studies that shows higher bulk properties .
The graphene and boron nitride filled polymer nanocomposites shows
higher thermal conductivity and higher strength for electronic packaging
applications.
resulting in the significant improvement of dynamic
mechanical, dielectric and thermal properties.
These results are beneficial to make the composites own great potential
applications, especially for electronics and aerospace industries.
15. References
1. Ziyin Lin a,b, Andrew Mcnamara c, Yan Liu b, Kyoung-sik Moon b, Ching-Ping
Wonga,d,-Composites Science and Technology 90 (2014) 123–128
2. Jinhong Yu, Xingyi Huang*, Chao Wu, Xinfeng Wu, Genlin Wang, Pingkai Jiang*Polymer 53 (2012) 471e480
3. H. Liem, H.S. Choy -Solid StateCommunications163(2013)41–45.
4. L. Ci,L.Song,C.Jin,D.Jariwala,D.Wu,Y.Li,A.Srivastava,Z.F.Wang,K.Storr, L.
Balicas,F.Liu,P.M.Ajayan,Nat.Mater.9(2010)430.
5. M.P.Levendorf,C.J.Kim,L.Brown,P.Y.Huang,R.W.Havener,D.A.Muller,J.
Park,Nature488(2012)627.
6. K.C. Yung,H.M.Liem,J.Appl.Polym.Sci.106(2007)3587.
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