The correlation of chemical composition and phase phenomena of polyamide blends has now been extended to binary aliphatic polyamide blends. The close similarity of structure and chemico-physical properties has usually made such an identification extremely difficult. This has now been overcome to a large extent by implementing enthalpy recovery measurements as the analytical procedure. It has been determined that, with the exception of blends of nylon 6 containing nylon 66, binary aliphatic polyamide blends will initially form phase-separated systems. This is in agreement with theoretical arguments based upon the dominant role of unfavourable interactions in polyamide blends. The nylon 6/nylon 66 blend represents the athermal condition, which coupled with the inability to detect any heterogeneity, suggests this blend may be homogeneous on a molecular scale. It has also been shown that in some instances transreaction in the melt can proceed rapidly during short periods of exposure to high temperature, e.g. 310°C for 4 min, with the formation of miscible blends. These observations are also reconciled qualitatively with theoretical considerations.
Посилання на статтю:
Mixing relationships in aliphatic polyamide blends / Thomas S. Ellis // Polymer. – 1992. – Vol 33. – P. 1469-1476.