Abstract
Bicomponent filaments of polyamide 6 (PA6) were produced with core/sheath geometries containing aluminium diethyl phosphinate (AlPi), and/or a montmorillonite nanoclay located individually or together in the sheath or core. A characterisation protocol based on thermogravimetric analysis (TGA) under both flowing air and nitrogen and pyrolysis combustion flow calorimetry (PCFC) enabled the effects of AlPi, clay and atmospheric oxygen to be assessed on PA6 thermal degradation. Knitted fabrics were assessed for flammability by vertical strip testing, which demonstrated that the relative location of the clay and flame retardant has a significant effect on burning behaviour. Correlation of the TGA/DTG, PCFC and burning sample results were discussed in terms of the effects of the roles of atmospheric oxygen and flame retardant components on the thermal degradation of PA6, especially when located in the sheath.