FINE STRUCTURE OF DRAWN NYLON6 ANNEALED IN ORGANIC SOLVENT (BENZYL ALCOHOL)

Abstract

Drawn nylon 6, previously heat-treated at 160°C in air, was annealed in benzyl alcohol, water and silicon oil at various temperature between 0°C and 120°C, and the fine structure was investigated by means of X-ray diffraction, density-gradient tube, and thermal analysis.The following results were obtained.1. Crystallinity of drawn nylon 6 showed a remakable increase by annealing in benzyl alcohol above 40°C, but hardly changed in water and silicon oil (up to 100°C). Decrease in crystallinity, due to a partial melting, observed in the initial stage of annealing.2. The orientation factor of b- and c-axis decreased in benzyl alcohol when annealing temperature was raised above 80°C, but that of a-axis was not appreciably affected by up to 120°C.The orientation factor of amorphous chain decreased remarkably above 20°C.3. The smectic structure of undrawn nylon 6 was transformed to α-form by annealing in benzyl alcohol, and stable (200) plane was formed even at such a low temperature as 20°C. For drawn sample, on the other hand, stable (200) plane was only formed above 100°C in the same solvent. The results suggests that rearrangement of the (200) plane of drawn nylon 6 becomes difficult by the drawing, due to the formation hydrogen bonds between adjacent (200) planes.4. Circular microvoids of 44_??_48A diameter were generated in drawn nylon 6 when annealed in benzyl alcohol at above 100°C.