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Hybrid materials
Inorganic
Polymers Particles
Thermally stable
Abrasion resistant
Weather resistant
Chemically inert
Rigid
Organic Polymers
Readily processableGood adhesion
Flexible
Tough
Organicinorganic
hybrids
Not physical mixtures but NanocompositeProperties of hybrids are not merely sum of individual component
Subdivision
Class IWeak bonds (hydrogen, van der waals bonds)
Class II - Strong chemical bonds (covalent or iono-covalent)
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Bone
the nanocompositethat has been aroundfor millions of years!
Nature combines (bio)organicand inorganic components
at nanometer scale
Example: mollusc shells / bone
/teeth tissues in vertebrates
Ancient man made hybridmaterialsEgyptian inks,
green bodies of china ceramics.
Used in Maya civilization
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Strategies to design functional hybrids
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Soft chemistry based routes
Conventional Sol-gel pathways
Low temperature route to inorganic oxides and glasses
Mild synthetic conditions
Combination of inorganic domains with organic or bioactive
molecules
Si
OO
HO
O
SiHO
OSi
O
O
Si
O OO
H
Si
SiO
SiHO
O
OH
O
Si
Si O
OHO
O
SiO
OSi
OSi
O
HO
O HO
OH
HO
Si OR
OR
OR
RO+ H2O/ H
+ / OH-
Si(OC2H5)4+ 4 H2O
H+ Or OH-SiO2 + 2 H2O + 4 C2H5OH
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Applications of hybrids
Speciality coatings
Superior abrasion resistance Anti-reflection
Tailored refractive indices
Protection from chemical agents
(anti-corrosion)
Dental applications
Matrix materials
Composites
Glass ionomer cements
Bondings
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Incident light Output light
Fluorescence
NLO
Amplified
lightScatteredlight
Optical functional particles
TiO2, CdS, CdSe, PbS ..
Abrasion resistant particles
SiO2, Al2O3, ZrO2
MatrixPolymer, Sol-gel glass
Optical applications
Other applications
Structural Materials
Catalysts
Electronics
Magnetic materials
Biomedical materials
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Synthesis of Inorganic Organic Hybrid Polyimides
NH2NH2 O
Oxydianiline
Paraphenylenediamine
NH2
NH2
OO
O O
O O
Pyromellitic dianhydr id
O O
O
OO
O
H2N O NH2H2N NH2
O NH
O
OO
O
NH
OH
O
OO
O
OH HONH
n
HONH
O
OO
O
NH
OH
O
OO
O
OH HONH
n
HN(EtO)3Si
HONH
O
OO
O
NH
OH
O
OO
O
OHHO
NH
n
HNSi
O
O
O
Si
Si
Si
O
O
O
O
OO
OO
O
N
O
OO
O
N
O
OO
O
n
NSi
O
O
O
Si
Si
Si
O
O
O
O
OO
OO
O
N
+ /
NH2(EtO)3Si
Si(OEt)4/MeSi(OEt)3
Thermal imidization
REACTION SCHEME:
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Applications:
substrate for flexible PCB Insulating material for high
temperature application
Microelectronic packaging
Coating
Property PI 5% TEOS+PI
Thermal stability
Glass transition
Dielectric constant
Tensile modulus
Tensile strength
558 0C
287
3.4
990 Mpa
90 Mpa
600 oC
291
2.9
1780 Mpa
85 Mpa
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Conclusion
Hybrids
Hybrid
propertiesSensors
Biomaterials
Responsive
materials
Nano-
composites
Functional
materials
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