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Dynamic-mechanical properties and cross-polarized, proton-enhanced, magic angle spinning 13C-NMR time constants of urethane acrylates—1. Homopolymer networks

✍ Scribed by A.B. Clayton; P.E.M. Allen; B.J. Keon; D.R.G. Williams

Publisher
Elsevier Science
Year
1993
Tongue
English
Weight
636 KB
Volume
29
Category
Article
ISSN
0014-3057

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✦ Synopsis

Dynamic-mechanical properties have been measured for a series of urethane acrylates containing polyether and polyester soft segments. Polymer glass transition temperatures predicted from a crosslinking relation showed better agreement with experimental Tg values than those obtained from applying the Fox equation to hard and soft segments in the polymer. Proton-enhanced, magic angle spinning ~3C-NMR time constants were obtained for a polyether soft segment urethane acrylate series. Increasing soft segment molecular weight resulted in a release of both near static and high frequency (mid-kHz) components of motion in the soft segment.

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