may 24, 2005 advanced liquid crystal technologies, inc. 1 liquid crystalline elastomers as...

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Liquid Crystalline Elastomers as Artificial Muscles

P.E. Cladis

Advanced Liquid Crystal Tech.

Summit, NJ 07902-1314

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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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

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Spontaneous Shape Change: Sample Preparation

P.E. Cladis: Phase Transitions in Liquid Crystalline Elastomers:A 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.

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Spontaneous Shape Change: Result

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Goal

1998 Symposium on Artificial Muscles and Liquid

Crystalline Elastomers Partially supported by NSF DMR 9871475

http://alct.com/fps/index.htm

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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First works

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Graduation

First Results: Thin samples

Kyushu University 2001

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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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‡

Sample 5CB & MBBA swelling agent

Monomer and Polydomain LCEsFrom Heino Finkelmann’s Lab

150m thick, 1x0.5mm2

Viewed in Polarizing Microscope

Swollen Nematic LSCE

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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MONO1

Dimension || n does not change!PR E 69, 021710 (2004)

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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MONO2 and POLY

PR E 69, 021710 (2004)

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Picture

PR E 69, 021710 (2004)

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Swelling Dynamics

POLY:

5CB ~8min

MBBA ~6min

MONO:

5CB ~16min

MBBA ~30min

Inverse swelling ratio

PR E 69, 021710 (2004)

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Swelling Temperature Dependence

Temperature dependence

None for Dry POLY

Lots for MONO and Swollen POLY

PR E 69, 021710 (2004)

MO

NO

1P

OL

Y

Dry

swollen

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Electric Field

Yusuf et al. PRE 71, 061702 (2005)

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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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

Better reorientation, larger shape change – cf Slide 8

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Temperature Dependence

Yusuf et al. PR E June 2005

MONO1 – maximum depends on sample thickness,

here about 20mMONO2 –

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Characteristic Times,

Yusuf et al. PR E June 2005

Switch on Switch off

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Voltage Dependence of 1/

Yusuf et al. PR E June 2005

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Voltage Summary

Yusuf et al. PR E June 2005

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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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.

May 24, 2005 Advanced Liquid Crystal Technologies, Inc.

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Kyushu 3/2001