Swelling Dynamics of Liquid Crystalline Elastomers
Jun GengLquid Crystal InstituteKent State University
Advisor: Dr. Peter Palffy-Muhoray
Outline Liquid crystal elastomer (LCE) sample
details and preparation Analysis of swelling based on Van der Waals
intermolecular potential Solvent swelling experiment Solvent vapor swelling experiment
2Liquid Crystal Institute, KSU
LCE Details & Preparation
3Liquid Crystal Institute, KSU
Finkelmann Spin Cast Nematic side chain LCE
Si O
CH3
H
O C
O
O OCH3
O
O
O
O C
O
O
CH3
CH3
CH3CH3
CH3
n
9
9
9
1
2
3
4
100 mol.%
72 mol.%
18 mol.%
10 mol.%
Si O
CH3
H
O C
O
O OCH3
O
O
O
O C
O
O
CH3
CH3
CH3CH3
CH3
n
9
9
9
1
2
3
4
100 mol.%
72 mol.%
18 mol.%
10 mol.%
Si O
CH3
H
O C
O
O OCH3
O
O
O
O C
O
O
CH3
CH3
CH3CH3
CH3
n
9
9
9
1
2
3
4
100 mol.%
72 mol.%
18 mol.%
10 mol.%
Si O
CH3
H
O C
O
O OCH3
O
O
O
O C
O
O
CH3
CH3
CH3CH3
CH3
n
9
9
9
1
2
3
4
100 mol.%
72 mol.%
18 mol.%
10 mol.%
Si O
85
CH3
H
methylsiloxane backbone
tri-functional crosslinker
biphenyl mesogen(side group)
Simple Analysis
4Liquid Crystal Institute, KSU
¢ f = ¢ fnem atic+ ¢ fm ix + ¢ felastic
Solvent Swelling Experiment Designed measurement cell
to simultaneously monitor Initial problems:
Solvent leaking UV glue degradation
5Liquid Crystal Institute, KSU
Swelling Experiment
solvent reservoir
solvent pump sample
holder
L1
L2
L3director
LCE
Solvent Vapor Swelling
LCE Bi-Rubber Strip Swelling
9Liquid Crystal Institute, KSU
Normal Rubber: RTV
Liquid Crystal Elastomer
Toluene
Toluene Vapor
Conclusion
Thanks to:
Jeremy taught me how to use those machines in machine shop and
supervised my activities, Paul who showed me how to make the
elastomers, Michele who lent me a
key to the lab, and Jake who told jokes sometimes.