ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
The dynamic moduli, E′ and E″, and tan δ for PET-CR, PET-EPDM, and PET-UR composites with unidirectional short fibers were studied as a function of temperature by using a Rheovibron. The temperature dependence of tan δ showed three peaks for PET-elastomer composites. The peaks at the low temperature corresponded to the main dispersion of the respective matrixes and the peak at about 140°C to the α-dispersion of PET fiber. A small and broad peak observed at a temperature between 60 and 120°C may be caused by the relaxation of the interface region between fibers and matrix. The longitudinal storage modulus for the composite E∥′ was given by the parallel model as \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm E'}_\parallel = V_f \cdot E'_f + V_m \cdot E'_m $\end{document}, where Ef′ and Em′ are the storage moduli for fiber and matrix and Vf and Vm are the volume fraction of fiber and matrix, respectively. In the transverse direction of fibers, the composite modulus E⊥′ was expressed by the logarithmic law of mixing as follows: \documentclass{article}\pagestyle{empty}\begin{document}$ \log E'_ \bot = V_f \cdot \log E'_f + V_m \cdot \log E'_m $\end{document}. The peak values of tan δ from the main dispersion of the respective matrixes were given by the equation, (tan δ⊥max)c/(tan δmax)m 1 - β · Vf, where (tan δ⊥max)c and (tan δmax)m are the maximum values of the loss tangent for the composite and matrix, respectively, and β is coefficient depending on matrix's type. The β value of PET-CR composite is the largest one among those of the composites.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1985.070300311
