Europhys. Lett, 47 (4), pp. 508-514 (1999)
Rheological properties of mono- and polydomain liquid crystalline elastomers exhibiting a broad smectic A phase
J. Weilepp 1,2, P. Stein 2, N. Aßfalg 3,
H. Finkelmann 3
P. Martinoty 2 and H. R. Brand 1
1 Theoretische Physik III, Universität Bayreuth - D-95440 Bayreuth, Germany
2 LDFC, UMR 7506, ULP-CNRS, Université Louis Pasteur
F-67070 Strasbourg Cedex, France
3 Institut für Makromolekulare Chemie, Universität Freiburg
D-79104 Freiburg, Germany
(received 19 January 1999; accepted in final form 18 June 1999)
PACS. 83.10Nn - Polymer dynamics.
PACS. 05.70Ln - Nonequilibrium and irreversible thermodynamics.
PACS. 61.30 - Liquid crystals.
We investigate the rheological properties of polydomain smectic A Side-Chain Liquid Crystalline Elastomers (SCLCE) by dynamic shear and compression measurements and find a very similar behavior for both experiments. We show that the dynamic shear modulus G' is independent of a precompression applied to the sample. In addition, we present the first dynamic measurements of the anisotropy of G' observed for the corresponding Liquid Single Crystal Elastomers (LSCE). We find that these monodomains show dynamically a dramatic difference depending on whether the shear is in a plane parallel or perpendicular to the layer normal, demonstrating the in-plane fluidity of the smectic layering.
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