Flame-Retardant Advanced Materials based on Binary and Ternary Polymer Blends: Morphology, Thermal Stability and Flame Retardancy

Flammability if polymers has always been a big challenge for plastic industry producers. Therefore, development of flame-retardant polymers has become a necessity in terms of safety standards. In this research, advanced materials based on high-density polyethylene (HDPE), polyamide 6 (PA6) and ethylene vinyl alcohol (EVOH) are manufactured as binary and ternary polymer blends reinforced with ammonium polyphosphate (APP) and clay nanoplatelets (NC) as flame retardants. Microstructure, thermal stability, and flame retardancy behavior of samples were studied by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and cone calorimetry tests. Results show that localization of APP and NC, minor phase domain size and compatibilizer incorporation can considerably affect thermal and flame retardant properties. The presence and increase of amount of APP in HDPE/PA6 binary blends slightly improved flame retardancy and thermal stability, where compatibilizer incorporation led to PA6 size reduction. The presence of third polymer, i.e., EVOH, enhanced compatibility featured by lower PA6 particle size, but compatibilizer was not efficient and did not improve flame retardancy.