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TSDC spectroscopy of relaxational and interfacial phenomena

“…By using these methods, many properties of polymers can be investigated such as chemical relaxation [220], cold crystallization [221] and stabilizer effects [222], influence of space charges on molecular microstructure [223] and thermal-induced structural changes [224,225], physical aging [226] and the effects of gamma and neutron radiation [227]. Individual polymers (such as polystyrene [228], polycaprolactone [229], polyoctenylene [230], polyvinylnaphthalene [231], unsaturated polyester resins [232,233]) and copolymers [234][235][236][237] as well as composites [238,239] were investigated by the TSDC and other relaxation techniques. Dipolar relaxation in amorphous [240,241], semi-crystalline [241] and liquid crystals [242] were investigated by the TSDC method, and the effects of polarisation and space charging were analysed for different systems [243][244][245].…”

Influence of backbone rigidity on the curing and the dielectric relaxations of unsaturated polyesters

“…Thus, the UPs are used in coatings, marine craft, land transportation, building, and construction as well as for large fabricated products (such as chemical and petroleum storage tanks). They are very popular, because of their low‐manufacturing cost, easy processing, low densities etc 1, 4…”

“…The α‐relaxation observed at the highest temperature is associated with the “dielectric glass transition” and at lower temperatures β‐relaxation or even γ‐relaxation can be detected. The α‐relaxation is associated to the beginning of segmental mobility within the polymer backbone, whereas the β‐ and γ‐relaxations are associated to fluctuations of short side chains 4, 12. Chemical structure and polarity are the basic factors controlling dielectric response in polymers.…”