Table 5.1 The dielectric loss/tangent delta maximum |

Figure 8.13 Mechanical and dielectric loss tangent tan 8 and NMR absorption line width (maximum slope, in gauss) of polytrifluorochloroethylene (Kel-F) (41). |

Fig. 16 shows the dielectric loss tangent, tas (j), as a function of frequency for PYR14TSFI, at different temperatures. In order to estimate T2 and 5 these tan plots can also be used. Curve fitting to equation (39) or coordinates of the maximum in tan(j) can be used to determine T2 and 8. [Pg.398]

This equilibrated frequency point is well determined by the loss tangent, tan, or dielectric loss, which predicts the ability of the material to convert the incoming energy into heat. For example, for water, the maximum value for the dielectric loss is around 2.0 GHz, which lies in the range of domestic microwave ovens. [Pg.45]

The relaxation time i can be correlated with the dielectric dispersion peak frequency, fmax, at which the dielectric loss tangent shows a maximum value, [Pg.388]

As illustrated in Appendix 1 it can be proved that the relaxation time T2 corresponds to the frequency of the maximum in dielectric loss tangent (tan ). In this method the characteristic time constant T2 was chosen from the frequency at the maximum in tan( ). Hence, by using the relation T2 = T -JS equation (20) can be modified to [Pg.390]

An analysis of the dielectric data similar to that for the dynamic mechanical data was undertaken. The natural logarithm of the time to peak maximum vs. 1/T was plotted for the two peak maxima observed in the dielectric loss tangent as shown in Figure 11. The activation energies derived from linear least squares fit of the data in these plots are listed in Table II. [Pg.238]

In conclusion, from a basic fact that the entropy of ER fluids. should greatly reduce after an electric field is applied, it is theoretically demonstrated that the maximum value of dielectric loss tangent of the dispersed particle should be larger than 0.1, which agrees well with the [Pg.449]

Research of influence of introduction of hexsaazocyclanes on a microstructure of polyethylene terephthalate is carried out. The increase in ability modified PETP to crystallization, in comparison with not modified PETP, as hexsaazocyclanes play a role of the original centers of crystallization is revealed. Research plasticization effect of hexsaazocyclanes on polyethylene terephthalate is carried out. It is revealed, hexsaazocyclanes introduction influences a maximum of a tangent of dielectric losses polyethylene terephthalate, displacing it aside smaller temperatures. [Pg.47]

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