Liquid Crystalline Elastomers as Artificial Muscles

1
Liquid Crystalline Elastomers as Artificial
Muscles
P.E. Cladis
Advanced Liquid Crystal Tech. Summit, NJ
07902-1314
2
Stress-Strain in Smectic A SLCEs
Strasbourg ILCC 1998 Nicole Assfalg
Alumni from Heino Finkelmann's Group See also
Liquid crystalline elastomers as artificial
muscles
3
Spontaneous Shape Change Sample Preparation
P.E. Cladis Phase Transitions in Liquid
Crystalline ElastomersA Fundamental Aspect of 
LCEs as Artificial Muscles in Interactive
Dynamics of Convection and Solidification, P.
Erhard, D.S. Riley and P.H. Steen (eds), Kluwer
Academic Publishers, Dordrecht (2001) p. 123.
4
Spontaneous Shape Change Result
5
Goal
1998 Symposium on Artificial Muscles and Liquid
Crystalline Elastomers
Partially supported by NSF DMR
9871475 http//alct.com/fps/index.htm
6
First works
7
Kyushu University 2001
8
Swelling Dynamics Samples

• PR E 69, 021710 (2004)
  
  Swelling dynamics of
  liquid crystal elastomers swollen with low
  molecular weight liquid crystals
  
  
  Yusril Yusuf, Y. Ono, Y. Sumisaki,
  P. E. Cladis, H. R. Brand, H.Finkelmann,Shoichi
  Kai

Swollen Nematic LSCE
9
MONO1
Dimension n does not change!
PR E 69, 021710 (2004)
10
MONO2 and POLY
PR E 69, 021710 (2004)
11
Picture
PR E 69, 021710 (2004)
12
Swelling Dynamics

• POLY
• 5CB 8min
• MBBA 6min
• MONO
• 5CB 16min
• MBBA 30min

PR E 69, 021710 (2004)
Inverse swelling ratio
13
Swelling Temperature Dependence
MONO1
Temperature dependence None for Dry POLY Lots
for MONO and Swollen POLY PR E 69, 021710 (2004)
POLY
14
Electric Field
Yusuf et al. PRE 71, 061702 (2005)
15
Voltage Dependence
Yusuf et al. Low-voltage-driven electromechanical
effects of swollen liquid-crystal elastomers ...
Threshold about 1.5V independent of sample
thickness typical for LMWLCs
16
Temperature Dependence
Yusuf et al. PR E June 2005
17
Characteristic Times, t
Yusuf et al. PR E June 2005
18
Voltage Dependence of 1/t
Yusuf et al. PR E June 2005
19
Voltage Summary
Yusuf et al. PR E June 2005
20
Acknowledgements We thank the IMA for the
opportunity to present these results. Yusril
Yusuf, Y. Ono, Y. Sumisaki, Jong-Hoon Huh, H. R.
Brand, H.Finkelmann, Shoichi Kai Nicole
Assfalg PEC thanks the Japan Society for the
Promotion of Sciences for a Research Prize
enabling this research.
21
Kyushu 3/2001