ISSN:
0098-1273
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Half-crystallization times t½, enthalpies of fusion ΔH, melting temperatures Tf glass transition temperatures Tg x-ray patterns, and morphologies were obtained for nine samples of poly(α-methyl-α-n-propyl-β-propiolactones) prepared from different homogeneous or heterogeneous initiators. The bulk of the results indicates that all samples can be classified into two categories: Polymers A having t½≏, 100 min, ΔH ≏ 26 J/g, Tf0 ≏ 376 K, Tg ≏ 275 K, and Polymers B having t½ ≏ 10 min, ΔH ≃ 14.5 J/g Tf0 ≏ 425 K and Tg ≏ 271 K. Polymers A were prepared with homogeneous initiators while polymers B were polymerized with heterogeneous intiators. The difference in crystallization behavior between polymers A and polymers B is certainly due to a difference in microstructure, brought about by the initiators, which has been qualitatively observed by NMR.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1981.180190104
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