ISSN:
0025-116X
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
Measurements on polyaniline using dielectric analysis (DEA, -50°C to 240°C, 0,4 Hz to 105 Hz), differential scanning calorimetry (DSC, 30°C to 240°C) and infrared spectroscopy (IR) after heat treatment from 25°C to 300°C are carried out. After conversion of DEA results to complex electric modulus, the conductivity relaxation time distribution can be obtained, which remains unchanged for temperatures below 160°C and becomes narrower in the temperature range from 180°C to 240°C due to the occurrence of crosslinking reactions, as is confirmed by the exothermic behavior above 160°C and by the decrease of the relative intensity of quinoid absorption with respect to that of the aromatic ring. The crosslinking reaction causes a decrease in dc conductivity, a narrowing in conductivity relaxation time distribution and an increase in activation energies for conductivity and conductivity relaxation.
Zusätzliches Material:
9 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/macp.1993.021940903
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