Thermally stimulated discharge current studies on low-temperature relaxation in epoxy resin

✍ Scribed by W-F. A. Su; S. H. Carr; J. O. Brittain

• Publisher: John Wiley and Sons
• Year: 1980
• Tongue: English
• Weight: 433 KB
• Volume: 25
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1980.070250709

✦ Synopsis

Abstract

Thermally stimulated discharge current (TSDC) analysis has been used to characterize the low‐temperature (100–300 K) molecular relaxation processes (β relaxation) of an epoxy resin. Experiments were performed on a resin system composed chiefly of tetraglycidyl‐4,4′‐diaminodiphenyl‐methane and diaminodiphenyl sulfone (TGDDM/DDS). Polarization of the epoxy of the resin appears to be due to preferential orientations of dipoles in the temperature range studied. The broad β‐dispersion peak exhibits considerable “structure,” and it promises to prove rich in information related to polarization and relaxation processes in the epoxy resins. It is seen that TSDC can reveal clearly the difference between the degree of curing for epoxy resins. Temperature dependence of a mean activation energy calculated from the discharging processes reveals several temperature ranges over which common molecular relaxation events are probably occurring.