Nematic elastomers: The influence of external mechanical stress on the liquid‐crystalline phase behavior

Die Makromolekulare Chemie 03/2003; 190(12):3269 - 3284. DOI: 10.1002/macp.1989.021901224


The influence of external mechanical stress on the nematic-isotropic phase transformation of nematic elastomers was investigated. The experimental results of IR-dichroism measurements in the nematic phase and stress-optical measurements in the isotropic phase are in good agreement with the theoretical predicitions of the phenomenological Landau-de Gennes theory. This is for the first time that a significant influence of an external field on the nematic-isotropic phase transformation temperature and on the nematic order parameter S has been proved.

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