Polymer Nanocomposities
Prof. V. Krishnakumar
Professor and Head
Department of Physics
Periyar University
Salem – 636...
Nanocomposites
"Composite Materials" are a new emerging class of
materials to overcome the limitations of monolithic
co...
Polymer Nanocomposites
-Combination of a polymer matrix and inclusions that
have at least one dimension (i.e. length, wi...
What is a polymer?
• A long molecule
made up from lots of
small molecules
called
• monomers.
All the same monomer
• Monomers all same
type (A)
• A + A + A + A 
• -A-A-A-A-
• eg poly(ethene)
polychloroethene
...
Different monomers
• Monomers of two
different types A + B
• A + B + A + B
 -A-B-A-B-
• eg polyamides
• polyesters
Addition polymerisation
• Monomers contain C=C bonds
• Double bond opens to (link) bond to next
monomer molecule
• Cha...
Copolymerisation
• when more than one monomer is used.
• An irregular chain structure will result eg
propene/ethene/pro...
Metallic Nanocomposites
Metals – size dependent property.
Metallic nanoparticles + polymers
Interesting for functional ...
Nonlinear optical properties
of nanomaterials
EM wave + nanomaterials
Surface Plasma Resonance effect
Various nonlinea...
3rd optical nonlinearity of routine materials
NLO Materials Third order
NLO (m2/W)
Response time
(S)
Large 3rd order ...
Versatility of Nano Composites
110
110
120
90
90
100
70
70
80
50
50
60
30
30
40
10
10
20
0
200 300 400...
Band gaps of different bulk and
nanocrystalline semiconductors
Material Bohr radius
(aB) in Å
Bulk band gap
(Eg ) in ...
Properties
Depend on Matrix, NanoFillers, etc
Improved Properties
Mechanical Properties (tensile
strength, stiffness, ...
Application
Depend on Matrix, NanoFillers etc…
• Automobile (gasoline tanks, bumper, interior and
exterior panels, etc…...
Polymer Nanocomposite
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Polymer Nanocomposite

Introduction to polymer nanocomposite
Published on: Mar 4, 2016
Published in: Education      
Source: www.slideshare.net


Transcripts - Polymer Nanocomposite

  • 1. Polymer Nanocomposities Prof. V. Krishnakumar Professor and Head Department of Physics Periyar University Salem – 636 011, India
  • 2. Nanocomposites "Composite Materials" are a new emerging class of materials to overcome the limitations of monolithic conventional materials. Why Nanocomposites Small filler size: – High surface to volume ratio • Small distance between fillers ® bulk interfacial material – Mechanical Properties • Increased ductility with no decrease of strength, • Scratching resistance – Optical properties • Light transmission characteristics depends on particle size
  • 3. Polymer Nanocomposites -Combination of a polymer matrix and inclusions that have at least one dimension (i.e. length, width, or thickness) in the nanometer size range known as polymer nano composities. • Polymers are light weight • Corrosion-resistant materials. • Traditional composites: the length scale of the fillers is in micrometers.
  • 4. What is a polymer? • A long molecule made up from lots of small molecules called • monomers.
  • 5. All the same monomer • Monomers all same type (A) • A + A + A + A  • -A-A-A-A- • eg poly(ethene) polychloroethene PVC
  • 6. Different monomers • Monomers of two different types A + B • A + B + A + B  -A-B-A-B- • eg polyamides • polyesters
  • 7. Addition polymerisation • Monomers contain C=C bonds • Double bond opens to (link) bond to next monomer molecule • Chain forms when same basic unit is repeated over and over. • Modern polymers also developed based on alkynes R-C C - R’
  • 8. Copolymerisation • when more than one monomer is used. • An irregular chain structure will result eg propene/ethene/propene/propene/ethene • Why might polymers designers want to design a polymer in this way? • (Hint) Intermolecular bonds!
  • 9. Metallic Nanocomposites Metals – size dependent property. Metallic nanoparticles + polymers Interesting for functional applications because the properties of nano- sized metals (optical, magnetic, dielectric, and thermal transport properties) leave unmodified after embedding in polymers.
  • 10. Nonlinear optical properties of nanomaterials EM wave + nanomaterials Surface Plasma Resonance effect Various nonlinear susceptibilities
  • 11. 3rd optical nonlinearity of routine materials NLO Materials Third order NLO (m2/W) Response time (S) Large 3rd order and fast response time -Essential Organic polymers 10-16 – 10-17 10-15 Semiconductors 10-17 10-13 Liquid crystals 10-7 10-6 Normally large 3rd nonlinear susceptibility and ultrafast response are difficult to achieve simultaneously however this can be achieved by using organic polymers
  • 12. Versatility of Nano Composites 110 110 120 90 90 100 70 70 80 50 50 60 30 30 40 10 10 20 0 200 300 400 500 600 700 800 Wavelength (nm) Transmittance (%) -10 200 300 400 500 600 700 Wavelength (nm) Transmittance (%) -10 200 300 400 500 600 700 800 Wavelength (nm) Transmittance (%) Host Polymer possible to tailor the properties of composite materials by selecting, shaping and distributing the raw materials can develop or design new materials with desired or improved properties Agglomeration Absorption band edge falls in invisible region Monodispersed Absorption edge falls in visible region
  • 13. Band gaps of different bulk and nanocrystalline semiconductors Material Bohr radius (aB) in Å Bulk band gap (Eg ) in eV Nano form- Band gap (En,g) in eV ZnS* CdS† PbS 15 30 200 3.5 2.4 0.4 5.2 5.52 5.2 These differences in properties of nanoparticles are used in microelectronics, quantum dot lasers, chemical sensors, data storage, and a host of other applications *Oleksandr L. Stroyuk, Volodymyr M. Dzhagan, Vitaliy V. Shvalagin, and Stepan Ya. Kuchmiy J. Phys. Chem. C 114 (2010) 220–225 †K. Manickathai, S. Kasi Viswanathan, M. Alagar, Indian J. Pure. Appl. Phys 46 (2008) 561- 566
  • 14. Properties Depend on Matrix, NanoFillers, etc Improved Properties Mechanical Properties (tensile strength, stiffness, toughness) Thermal expansion Thermal conductivity Ablation resistance Chemical resistance Disadvantage Viscosity increase (limits processability) Sedimentation Dispersion and distribution difficulties
  • 15. Application Depend on Matrix, NanoFillers etc… • Automobile (gasoline tanks, bumper, interior and exterior panels, etc…) • Electronic and Electrical (Printed circuits and electronic components) • Food packing (Containers) • Cosmetics (Controlled release of “active ingredients) • Environment (Biodegradable materials) • Gas barrier (Tennis balls, food and beverage packing) • Military and aerospace