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Ultrasonic detection of segmental relaxations in thermoplastic polyurethanes

✍ Scribed by A. W. Aziz; S. N. Lawandy

Publisher
John Wiley and Sons
Year
1986
Tongue
English
Weight
402 KB
Volume
31
Category
Article
ISSN
0021-8995

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✦ Synopsis

The change in attenuation of longitudinal waves has been measured as a function of frequency and temperature for thermoplastic polyurethanes of different hardness covering a range from rubbery hardness to plastic. Analysis of the results show some segmental relaxations and the activation energies were calculated from the ultrasonic measurements. These activation energies were indirectly related to the fatigue failure of the polymer. This failure was expressed as cut growth.

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