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Influence of chemical structure on free volume in epoxy resins: A positron annihilation study

✍ Scribed by Kathleen Jeffrey; Richard A. Pethrick

Publisher
Elsevier Science
Year
1994
Tongue
English
Weight
460 KB
Volume
30
Category
Article
ISSN
0014-3057

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✦ Synopsis

Positron annihilation lifetime (PAL) measurements are reported on a series of chemically different cured epoxy resin systems. Analysis of PAL data yields indicates the effects of changes in the cure temperature and chemical structure on the average molecular free volume size. A comparison of PAL with conventional density measurements on samples exhibiting different values of the glass transition temperature (T 8) indicates the importance of microscopic voids on the physical properties of epoxy resins. This study gives new insights into the effects of structural changes in thermosets on their Tg behaviour.

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