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Relaxation phenomena in homopolymers and copolymers of ethylene and propylene

✍ Scribed by Kontos, E. G. ;Slichter, W. P.

Publisher
John Wiley and Sons
Year
1962
Weight
424 KB
Volume
61
Category
Article
ISSN
0022-3832

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✦ Synopsis

Abstract

The physical properties of ethylene–propylene copolymers depend partly on the overall proportions of the monomers and on the arrangement of the two monomers within the polymer. The effect of composition upon the glass transition and related relaxation is reported, with comparisons drawn from dilatometry, dynamic mechanical loss, and measurements of nuclear magnetic resonance absorption. The relaxation times ranged from about 10^3^ sec. to about 10^−7^ sec. The copolymers varied in composition from an ethylene: propylene mole ratio of 85:15 to a ratio of 16:84, and the homopolymers were also studied. The relaxation phenomena are interpreted qualitatively in terms of the expected temperature dependence of the spectra of frequencies of molecular motion.

📜 SIMILAR VOLUMES

Analysis and properties of ethylene–prop
Analysis and properties of ethylene–propylene copolymers
✍ Smith, W. E. ;Stoffer, R. L. ;Hannan, R. B. 📂 Article 📅 1962 🏛 John Wiley and Sons ⚖ 266 KB

## Abstract Copolymers of ethylene and C^14^‐labeled propylene were prepared with a metal‐oxide catalyst which polymerizes ethylene to a high density polymer. Methyl branches arising from the propylene were counted radiochemically and then related to the infrared absorption of films at 8.7 μ. This