Influence of crystallization conditions on the crystal order and dynamic thermal behavior of nylon 1010

Nylon 1010 crystals with different size and perfection were prepared under various crystallization conditions. Temperature-varied X-ray diffraction and transmission electron microscopy were used to investigate the structure and morphology of these crystals. The pseudo-hexagonal phase (also known as γ modification) of nylon 1010 was obtained by heating the quenched sample to a high temperature, where this phase is stable. Cooling of the γ modification sample immediately resulted in a Brill transition into the triclinic form. The WAXD and TEM results showed that the crystal structure at room temperature as well as its thermal behavior on heating is strongly influenced by the crystallization conditions. No Brill transition temperature was observed for large or perfect crystals in both the heating and the cooling process, i.e. for melt-crystallized spherulitic crystals and lamellar single crystals grown from dilute solution. This shows that the Brill transition depends on the size and perfection of the crystal.