ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Dielectric properties and molecular motion were studied by use ofdielectric spectroscopy and differential scanning calorimetry for twoblends, fully transesterificated polyarylate of bisphenol A withterephthalate/isophthalate (50/50) (PA)/polycarbonate of bisphenol A(PC) blends and PA/poly(ethylene terephthalate) (PET) blends. All thequenched PA/PC and PA/PET blends were amorphous and the glasstransition temperature (Tg) was varied with the blends ratioaccording to Gordon-Taylor equation. The PA/PET blends with more than60% of PET crystallized above the crystallization temperature. ThePA/PC and PA/PET blends showed two dielectric relaxations, αabove Tg and γ below Tg, which are related to a glasstransition and a local motion of short segment, respectively. Theα relaxation moved to lower temperatures as PC or PET contentincreases, reflecting the lowering Tg faithfully. In the PA/PETblends, the static (ɛ0) and the limiting dielectricconstant (ɛ∞), and the increment (Δɛ) for the α relaxation decreases with increasingtemperature and the decrease falled on one curve, independent of theblend ratio. Any ferro- and piezoelectricity were not observed fortwo blends.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1004859617366
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