The potential for ultrasound to improve nanoparticle dispersion and increase flame resistance in fibre-forming polymers

摘要: Abstract The effects of exposing to ultrasound compounded melts polypropylene (PP) and polyamide 6 (PA6) formulations comprising nanoclays both alone in the presence other flame retardants are explored terms their improved dispersion, consequent ability be extruded into filaments burning behaviour. Clays used were Nanomer 1.3T PP this Cloisite 25A PA6. Flame selected ammonium polyphosphate (in PP) aluminium phosphinate PA6) present at low concentration 5 wt%. 50 100 W 30 kHz ultrasonic probes fitted end compounder barrel collected as strands which pelletised then separately filaments. Compounded extrudates, fabrics assessed morphologically by optical microscopy, SEM-EDS TEM. Thermal stability flammability undertaken thermal analysis limiting oxygen index for fabrics, vertical strip testing. Clear evidence dispersion after treatment has been shown using image processing software data samples increased intercalation exfoliation clays PA6 demonstrated Increased ease extrusion was also noted. For formulations, ultrasonification reduced fabric rates drip formation. In PA6, only positive seen PA6/Cloisite 25A/aluminium formulation showed some synergy LOI polymer from 21.1 23.3 vol%. Fabric behaviour more mixed with no clear cut advantages being apparent for PA6.