✦ LIBER ✦
Properties of urethane elastomers—III. Depolarization currents from unsaturated polyurethanes based on 4,4′-diphenylmethane diisocyanate
✍ Scribed by I. Diaconu; C. Ciobanu; Cr.I. Simionescu
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 216 KB
- Volume
- 26
- Category
- Article
- ISSN
- 0014-3057
No coin nor oath required. For personal study only.
✦ Synopsis
The dielectric relaxation processes in polyurethanes based on 4,4'-diphenylmethane diisocyanate (MDI) and both saturated and unsaturated polyesters were studied in the range 240-410 K using thermally stimulated depolarization currents method (TSDC). The structure of the TSDC spectra and the location and intensity of the constituent peaks depend both on the urethane content and thermal history of the polymer. The relaxation processes have been associated with the molecular motions within domains with distinct hard segment concentrations.