1. Increased surface area on nanoparticles
Why Nanocomposites?
Size does matter
      Increased surface area on nanoparticles
               
Microparticles
Nanoparticles

2. Why Nanocomposites?  Multi-functionality
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 particle size dependent

3. Nanocomposite as a Multiscale System
Macroscale composite structures
Clustering of nanoparticles - micron scale
Interface - affected zones - several to tens of nanometers - gradient of properties
Polymer chain immobilization at particle surface is controlled by electronic and atomic level structure
1 s - 1h s s

4. The Glass transition temperature of nanocomposite thin films
Background: The glass transition temperature of polymer thin films
Influence of
i) single walled carbon nanotubes,
(ii) C60 fullerenes (“buckyballs”) and
(iii) mica-type layered silicate inorganic clays
on the Tg of thin polymer films in the nanometer thickness range
from mmptdpublic.jsc.nasa.gov/jscnano/
20-50 nm
P. F. Green et al, U Texas
Polymer coil Rg~2-20 nm

5. The Glass transition of Polymer thin film nanocomposites
C60, and carbon nanotubes have a similar effect
PS: b=9
Nanocomposite: b=4
Decrease in b reflects the
increase in fraction of the
slowly relaxing domains
The effect of nanoparticles is to
increase the effective
fraction of slowly relaxing
domains in the sample
P. F. Green et al, U Texas