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flections. In a fiber diagram from a sample having cylindrical symmetry, one could imagine this pattern being spun about the central spot.

Unclassified I54L DECL ASSI FICATION/ DOWN GRAOING SCHEDULE 16.Thidocunienthas beena pprovdV for public :olecnio and sale; its istruti s unlimited. 1S. SUPPLEMENTARY MOTES Submitted to Macromolecules KEY WORDS (ContInue on reverse ede It neceeemy end Identify by block number)Chain conformation; crystalline transformation; Curie temperature; dielectric anomaly; ferroelectric-paraelectric transition; intramolecular transformation; piezoelectricity; polytrifluoroethylene; pyroelectricity; thermal expansion; trifluoroethylene copolymer; vinylidene fluoride copolymer ZABSTRACT (Continue an reverse aide If necoesesv and Identify by block numnber)The effect of temperature on the structure and dielectric properties of a 52/ LLJ vestigated at temperatures up to 140 6C. Undrawn or unpoled specimens contain j an intimate mixture of two disordered crystalline phases, both of which under-LA.. Ri 125 011 -,t-14TY CLASSIFICATION OF THIS PAGE(han Date Entered)Block 20.to a single, well-ordered all-trans conformation, leading to remanent polarization with piezoelectric and pyroelectric coefficients comparable to those of poly(vinylidene fluoride). The changes in crystal phase and dipole orientation upon poling result in a reduction of the dielectric constant at room temperature a shift of the dielectric anomaly to -80 C, stability of the all-trans crystal phase to somewhat higher temperatures, and a discrete change in d-spacing to that of the disordered 3/1-helical conformation at the transition region. The loss of polarization in poled specimens at this ferroelectric-to-paraelectric transition is attributable primarily to the molecular change from the polar all-trans conformation to its non-polAr, disordered 3/1-helical counterpart, as well as to the onset of rotational dipolar motions leading to the die'ectric anomaly. The changes in crystal phase and dipole orientation upon poling result in a reduction of the dielectric constant at room temperature, a shift of the dielectric anomaly to -80 0 C, stability of the all-trans crystal phase to somewhat higher temperatures, and a discrete change in d-spacing to that of the disordered 3/1 helical conformation at the transition region. The loss of polarization in poled specimens at this ferroelectric-to-paraelectric transition is attributable primarily to the molecular change from the polar all-trans conformation to its non-polar, disordered 3/1-helical counterpart, as well as to the onset of rotational dipolar motions leading to the dielectric anomaly.

In this study, we describe a distinct nematic liquid crystal with polar ordering which is formed from the polar rod-like aromatic copolyester comprising 4-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid. The polarity in the nematic phase appears along the nematic director as determined by second-harmonic generation (SHG). It was found that SHG activity appears in compounds with a high degree of polymerization. This suggests that the strong dipole-dipole interaction between polar rod-like molecules is the origin of the polar structure.