Broadband dielectric spectroscopy effects

The successful development of the time-domain dielectric spectroscopy method (generally called time-domain spectroscopy, TDS) [79-86] and broadband dielectric spectroscopy (BDS) [3,87-90] have radically changed the attitude towards DS, making it an effective tool for investigation of solids and liquids on the macroscopic, mesoscopic, and, to some extent, microscopic levels. 

In this chapter broadband dielectric spectroscopy (BDS) is employed to polymeric blend systems. In its modem form BDS can cover an extraordinary broad frequency range from 10 " to 10 Hz. Therefore, molecular and collective dipolar fluctuations, charge transport, and polarization effects at inner phase boundaries can be investigated in detail including its temperature dependence. 

G. Floudas, Effect of pressure on the dielectric spectra of polymeric systems (Chapter 8), in Broadband Dielectric Spectroscopy, ed. by F. Kremer, A. Schonhals (Springer, Berlin, 2003)... 

Richert R (2010) Non-linear effects in physics of dielectrics. Arizona State University, Tutorial Broadband Dielectric Spectroscopy and its Applications http //www.uni-leipzig.de/ ids2012/ tutorials/richert2010.pdf. Cited 23 Dec 2015... 

Natural rubber (NR) is a well studied elastomer. Of particular interest is the ability of NR to crystallize, specifically the strain-induced crystallization that takes place whilst the material is stretched. Moreover, in many elastomer applications, network chain dynamics under external stress/strain are critical for determining ultimate performance. Thus, a study on how the strain-induced crystallization affects the dynamics of a rubbery material is of outmost importance. Lee et al [1] reported their initial findings on the role of uniaxial extension on the relaxation behavior of cross-linked polyisoprene by means of dielectric spectroscopy. Nonetheless, to our best knowledge no in-depth study of the effects of strain induced crystallization on the molecular dynamics of NR has been undertaken, analyzing the relaxation spectra and correlating the molecular motion of chains with its structure. Broadband dielectric spectroscopy (BDS) has been chosen in order to study the dynamic features of segmental dynamics, because it is a comparatively simple technique for the analysis of the relaxation behaviour over a suitable frequency interval. This study is important from a basic and practical point of view, since an elongated crosslinked polymer at equilibrium may be considered as a new anisotropic material whose distribution of relaxation times could be affected by the orientation of the chains. 

Broadband dielectric spectroscopy is a powerful technique for the investigation of physical effects occurring in polymers and polymer composites, such as molecular mobility, polarization, conductivity, interfacial phenomena, phase changes, polymerization, crystallization, etc. [9], Presented results are aimed only at room temperature measurements of conductivity and dielectric permittivity. The measurements of the electrical conductivity o, real and imaginary part of dielectric... 

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