Ferroelectric Liquid Crystal Polymers

Kremer F (ed) (1992) Ferroelectric liquid crystal polymers. In Polym Adv Technol, vol 3(5). Wiley, Chichester... 

Spontaneous Polarization Behavior of FLCPs (Ferroelectric Liquid Crystal Polymers)... 

Like the ferroelectric liquid crystal polymers,the co-polymers of the PVDF type require poling. By contrast, the polarization of an LB film is solidly built into the structure, and is only removed,if fields in excess of the dielectric breakdown field are applied. The main practical disadvantage associated with VF2/VF3 co-polymers is their microphonic activity. Fortunately, the LB films studied to date, with the exception of the azobenzene compounds, have piezoelectric coefficients low enough to be undetectable. 

Kremer, F, ed.. Ferroelectric liquid crystal polymers. Special issue. Polym. Adv. Tech-/lo/., i(5) (1995). 

Gouda, F., Skarp, K., Andersson, G., Lagerwall, S. T., Stebler. B., and Helgee, B., Soft mode response and rotational viscosity of a ferroelectric liquid crystal polymer, Jpn. J. Appl. Phys., 34, 5653-5657 (1995). 

The storage effects could also be realized in polymer liquid crystals. On cooling, ferroelectric liquid crystal polymers with the electric field applied, the macroscopic polarization is frozen in the glassy state [74]. Thus, the polymer film becomes a pyroelectric and a piezoelectric. Unfortunately, the glassy state is too viscous to allow the field-induced reorientation of the polarization and the film cannot be considered to be a ferroelectric. 

Further invention accomplished to arrive at a ferroelectric liquid crystal polymer which not only exhibits ferroelectricity even at around room temperature, but also has so fast response speed to the external factors as to be able to display motion pictures, and also can be used as display elements for large size screens and curved screens [145]. 

S. Uchida K. Morita K. Hashimoto, Ferroelectric liquid crystal polymer US Patent 4,844,835, Assigned to Idenitsu-Kosan-Co-Ltd, July 4,1989. 

Ferroelectric Liquid Crystal Polymers. The synunetry requirements necessary for ferroelectricity in low-molecular-mass compounds are also valid for polymer meso-phases. If a tilted chiral smectic phase is stable after a polymerization process, it must be ferroelectric. Following this idea the first polymeric liquid crystalline ferroelectric was synthesized by Shibayev et al. [197]. The substance is a comb-like homopolymer IV)... 

Reviews of ferroelectric liquid crystal polymers. can be found in the following ... 

Sekiya, X, Yuasa, K., Uchida, S., Hachiya, S., Hashimoto, K., and Kawasaki, N., Ferroelectric liquid crystal polymers and related model compounds with a low to moderate degree of polymerisation, Liq. Cryst., 14, 1255, 1993. 

Fig. 4.32. 3D plot of the dielectric loss versus frequency and temperature for a thin oriented sample of the ferroelectric liquid crystal polymer 43 (Table 4.5). (From Ref 161 with permission of Hiithig Publishing Ltd.)... 

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