THE EFFECT OF ELECTRIC-FIELD ON THE CRYSTALLIZATION OF POLYAMIDE-6,6 BY RHEOLOGICAL MEASUREMENT

The effect of the electric field on crystallization behaviour of polya mide-6,6 (PA-6,6) was investigated by a rheological measurement. The c rystallization kinetics were estimated by monitoring the changes in th e absolute value of complex viscosity during crystallization. In both isothermal and nonisothermal crystallization experiments, it is observ ed that the crystallization rate of PA-6,6 decreases with increasing t he applied electrical field. This phenomenon is explained by the orien tation of dipole moments in amide groups under the electric field. In the PA-6,6, dipoles of amide groups are aligned antiparallel to each o ther to yield a stable crystal structure. The external electric field disturbs the antiparallel orientation of dipoles and thus prevents the chain packing during crystallization. Copyright (C) 1996 Elsevier Sci ence Ltd.