Temperature–frequency transformation in dielectric thermal analysis (DETA) of wood relaxation properties
✍ Scribed by Grzegorz Hoffmann; Stefan Poliszko
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 470 KB
- Volume
- 59
- Category
- Article
- ISSN
- 0021-8995
No coin nor oath required. For personal study only.
✦ Synopsis
A direct method for the transformation of temperature dependences of dielectric loss factor (c") obtained a t any frequency, into frequency dependences a t any temperature was worked out. The method was tested and the accuracy of the analysis was verified for the case of local processes of dielectric relaxation in wood in the directions parallel and perpendicular to the fibers. The obtained solutions proved that a common representative of all considered dielectric absorption spectra is the distribution of dielectric absorption intensity vs. free energy of activation of an adequate individual relaxation process. The origin of the difference in the peak intensity of dielectric relaxation spectra, obtained a t various experimental temperatures, was explained as a consequence of simple proportionality between the free energy of activation of relaxation and the energy of activation of rotators generation. A recently developed method of transformation is believed to give a new universal approach to the dielectric and dynamic mechanical thermal analysis of polymer systems.