Structure-property relationships dielectric properties

Synthesis and Structure-Property Relationships of Lo w-Dielectric-C onstant Fluorinated Poly acrylates ... 

Very recently we8 reported on a class of processable heavily fluorinated acrylic resins that exhibit dielectric constants as low as 2.10, very close to the minimum known values. In this chapter we report on the preparation of a series of processable heavily fluorinated acrylic and methacrylic homo- and copolymers that exhibit dielectric constants as low as 2.06, and the factors that affect the reduction of dielectric constant from structure-property relationships is elucidated.9... 

Liu A, Wang X, Wang L et al. (2007) Prediction of dielectric constants and glass transition temperatures of polymers by quantitative structure-property relationships. Eur Polym J 43 989-995... 

Because of the structural variety possible with polyimides, many smdies have sought to understand their structure-property relationships, often focusing on one specific target property. Such studies have included those aimed at understanding thermal expansion behavior, optical properties electronic structure, dielectric constant and loss, PTIR analysis, adhesion, water absorption, and molecular ordering, as well as others. The references cited... 

Fluorinated polyimides have been made with a broad range of chemical structures and possess an equally wide range of properties. Their value as low-dielectric, hydrophobic, and thermally stable materials is now well established in industry, and work continues to try to further understand underlying principles of structure-property relationships. 

For a deeper understanding of structure-property relationships it is useful to consider the effect of carbon black grade and concentration as well as polymer type on the dielectric properties more closely. In Fig. 29 the real part of the a.c.-conductivity o at 20 °C of a series of rubber composites, consisting of the more polar statistical co-polymer NBR and the fine black N220, is depicted for various filler concentrations in the high frequency regime up to 1 GHz. For the lower carbon black concentrations, a power law behavior with exponent around 0.6 is observed, while the highly filled com-... 

Schweitzer, R.C. and Morris, J.B. (1999). The Development of a Quantitative Structure Property Relationship (QSPR) for the Prediction of Dielectric Constants Using Neural Networks. Anal. Chim.Acta, 384,285-303. 

Results of dielectric studies of a series of nanocomposites based on a semiaromatic PA-1 ITIO with HAp helped to explain the structure-property relationships [Sender, 2008], For dry, neat PA-llTlO, a symmetric depolarization peak, detected by TSC near Tg measured by DSC, was attributed to dielectric dynamic glass relaxation. By DDS, two distinct high-temperature processes were distinguished when plotting the experimental data points versus HT. The dependence is displayed in Figure 13.2, where the two dashed lines show the complex dielectric permittivity fitted by the Havriliak-Negami equation ... 

Perovskites Structure-Property Relationships 6.2 Dielectric Perovskites 6.2.1 General Properties... 

Phthalazinone, 355 synthesis of, 356 Phthalic anhydride, 101 Phthalic anhydride-glycerol reaction, 19 Physical properties. See also Barrier properties Dielectric properties Mechanical properties Molecular weight Optical properties Structure-property relationships Thermal properties of aliphatic polyesters, 40-44 of aromatic-aliphatic polyesters, 44-47 of aromatic polyesters, 47-53 of aromatic polymers, 273-274 of epoxy-phenol networks, 413-416 molecular weight and, 3 of PBT, PEN, and PTT, 44-46 of polyester-ether thermoplastic elastomers, 54 of polyesters, 32-60 of polyimides, 273-287 of polymers, 3... 

---