STRUCTURE AND TEMPERATURE-INDUCED STRUCTURAL-CHANGES OF VARIOUS POLYAMIDES

The structure and temperature-induced structural changes of three poly amides, PA 6, PA 6.6 and PA 6.10, were investigated by X-ray diffracti on. In all three polyamides a reduction of the distance in the hydroge n-bonded sheets was measured. A discontinuity in the temperature depen dence of the d-spacings d100 and d110+010 was found only in PA 6.10 an d 6.6. This can be interpreted by a change of the arrangement of the h ydrogen bonds. Because of the existence of two equatorial peaks up to the melting point in PA 6 and PA 6.10, a non-statistic distribution of the hydrogen bonds can be assumed. In PA 6 the planar arrangement of the hydrogen bonds is maintained.