DIELECTRIC HYSTERESIS LOOP IN ALICYCLIC AND AROMATIC POLYAMIDES

The relationship between electric displacement D and electric field E was studied for alicyclic polyamides of 1,3-bis(aminomethyl)cyclohexane and adipic, pimelic and sebacic acids, an aromatic polyamide prepared from hexamethylenediamine (HMD) and isophthalic acid and a copolyamide of HMD with isophthalic and terephthalic acids. Quenched samples of these polyamides were poorly crystalline or amorphous and exhibited a D-E hysteresis loop with the remanent polarization of 26 to 38 mC.m-2. The remanent polarizations disappeared at the glass transition temperature of each sample. The origin of the D-E hysteresis loop is attributable to amide groups in amorphous regions.