Electrically Conducting Polymer Compositions (ECPCs)

1
Electrically Conducting Polymer Compositions
(ECPCs)

• Ragy T. Ragheb
• Dr. J. Riffle
• Department of Chemistry
• Virginia Tech
• Blacksburg, VA 24060

2
Outline

• Background
• Objective
• Compositions
• Polymer Matrix (3 steps)
• Electric Filler
• Curing Process
• Stress Applications
• Conclusions
• Acknowledgements

3
Background What is an ECPC?

• Two components
• Polymer matrix
• Networked polysiloxane
• Thermally stable
• Moisture resistant
• Electric Filler
• Silver flakelets
• Very conductive
• Toughening enhancer

4
Background contd.

• Perculation
• Change in Cond. Vs. Change in vol filler
• Increase in vol filler decrease in number of
  conduction paths
• Variables
• Temperature change
• Adsorption of water
• Air voids

5
Objective

• Achieve critical volume fraction of silver
• Observe change in conductivity with degree of
  applied stress

6
Compositions Polymer Matrix
Step 1
7
Compositions Polymer Matrix
Step 2
8
Compositions Polymer Matrix
Step 3
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Compositions Electric Filler

• Silver Flakelets
• 1.0-5.0 micrometers in diameter

Mol CN Vol Ag Conductive
10 22.3 No
27 28.8 Yes
54 28 No
10
Compositions Curing Process

• STEP 1 Add Pt catalyst, crosslinking agent, then
  polymer
• Mix and degas
• STEP 2 Add silver particles
• Mix and degas
• STEP 3 Prepare thin films on glass slides for
  conductivity tests (Cured at 80C overnight)

11
Stress Applications
12
Conclusions

• 27 mole CN functional groups with 28.8 wt Ag
  proved to be conductive.
• Epoxy Resin proved to be suitable for stress test

13
Acknowledgements

• Nanosonic Ltd.