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VOLUME 61 (1995) | ISSUE 2 |
PAGE 131
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Smectic C* (of F*)-Smectic A phase transition in side chain polymers investigated by piezoelectric technique
Iablonskii S. , Pikin S., Sparavigna A. , Strigazzi A.
The measurement of the piezoelectric response, by means of a new technique sensitive to the polar ordering of the polymer liquid crystals, has been used to detect the temperature phase transitions of the ferroelectric chiral side chain polymer P5*M and of the copolymer C25. As a result of these investigations, the sharp jump of the piezoelectric signal has been observed in the vicinity of the smectic C*-smectic A and smectic F*-smectic A phase transitions. In this letter we present a theoretical model, which takes into account the peculiarities of the structure of polymer ferroelectrics, and propose an explanation for the pretransitional behavior in the piezoelectric signal at the transition temperature. © 1995 American Institute of Physics.
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