Shear Flow Induced Transition from Liquid-Crystalline to Polymer Behavior in Side-Chain Liquid Crystal Polymers
- 6 January 1997
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 78 (1) , 70-73
- https://doi.org/10.1103/physrevlett.78.70
Abstract
We determine the structure and conformation of side-chain liquid-crystalline polymers subjected to shear flow in the vicinity of the smectic phase by neutron scattering on the velocity gradient plane. Below the nematic-smectic transition we observe a typical liquid-crystal behavior; the smectic layers slide, leading to a main-chain elongation parallel to the velocity direction. In contrast, a shear applied above the transition induces a tilted main-chain conformation which is typical for polymer behavior.Keywords
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