Loss tangent (internal friction) for high relaxation strengths and a lognormal distribution of relaxation and retardation times |
| |
Authors: | F Povolo C L Matteo |
| |
Institution: | (1) Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Dto. de Física Pabellón 1, Ciudad Universitaria, (1428) Buenos Aires, Argentina;(2) Consejo Nacional de Investigaciones Cientificas y Técnicas, Buenos Aires, Argentina;(3) Present address: Dto. de Ciencias de Materiales, Comisión Nacional de Energía Atómica, Av. de Libertador 8250, (1429) Buenos Aires, Argentina |
| |
Abstract: | Summary The loss tangent (internal friction) is evaluated numerically for a lognormal distribution of retardation or relaxation times
and high relaxation strengths. It is shown that the loss tangent peak becomes more asymmetrical and the peak width, at half-maximum,
decreases as the relaxation strength increases, dropping down to values corresponding to a Debye peak at very large relaxation
strengths. Furthermore, the asymmetry of the peak can be used to establish if the lognormal distribution is in the retardation
or in the relaxation spectrum. Finally, a procedure which can be used to obtain the relaxation strength, the geometrical parameter
of the distribution and the average retardation or relaxation time, from the experimental loss tangentvs. frequency curves, is described. This procedure is applied to actual experimental data reported in the literature for polystyrene.
The authors of this paper have agreed to not receive the proofs for correction. |
| |
Keywords: | Energy distribution and transfer relaxation |
本文献已被 SpringerLink 等数据库收录! |
|