This paper deals with fabrication and characterization of unique polyphenylene ether/polystyrene/nylon-6/glass composites. Compounding of ternary blends with glass fibres was performed using twin screw co-rotating extruder. Test specimens were fabricated by compression moulding and injection moulding. Effect of maleic anhydride, fibre type (chopped and long), fibre content (30 wt. % and 40 wt. %) and fabrication method (compression moulding and injection moulding) on mechanical and thermal properties was studied. Maleic anhydride negatively influenced mechanical and thermal properties. Composites with 40 wt. % chopped fibres showed superior mechanical strength and those with 30 wt. % long fibres showed superior thermal properties, tensile and flexural moduli. Injection moulded specimens exhibited superior mechanical and thermal properties. The composites were studied for moisture content, density, melt flow index, glass transition temperature, thermal degradation temperature and mechanical properties. Interfacial strength was examined using scanning electron microscopy.

Polyphenylene ether (PPE) is a polymer with very high glass transition temperature, superior thermal stability but poor melt processability. Mainly to improve its processability and chemical resistance, it is blended with Polystyrene (PS) and Nylon-6, respectively. In this research, ternary blends of PPE/PS/Nylon-6 were prepared using co-rotating twin screw extrusion and test specimens were injection molded. The influence of Maleic anhydride and screw speed on the mechanical and thermal properties of the ternary blends was investigated. The 40/40/20 blends, without Maleic anhydride, processed at screw speed of 600 min–1 showed highest tensile, flexural and impact strengths of 65.74 MPa, 82.22 MPa and 8.88 kJ/m2, respectively. Complete miscibility of the three polymers in the ternary blend was evidenced by scanning electron micrographs. Glass transition temperature of the ternary blend was 127 °C. High thermal and dimensional stability of the blend was evidenced by lowest volatile mass and highest residual mass at 800 °C along with decomposition temperature of 458.6 °C. Maleic anhydride was not effective as compatibilizer in improving the mechanical properties of the ternary blend.

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This paper deals with the effect of melamine cyanurate on the thermal and fire retardant behaviour of chopped glass fibre (40 wt.%) reinforced polyphenylene ether/polystyrene/nylon-6 (40/40/20 wt. %) which are processed in a twin screw co-rotating extruder. The composite specimens were fabricated by injection moulding. Addition of melamine cyanurate decreased the amount of toxic gases and organic volatile compounds, crystallinity, crystalline temperature and melt temperature but the same fire-retardant increased glass transition temperature and heat distortion temperature of the ternary alloy. Flame retardancy with V0 and V2 rating along with Limiting Oxygen Index 35% was observed in UL94 test for 5 wt. % and 10 wt. % addition of melamine cyanurate, respectively. Addition of melamine cyanurate increased tensile modulus and elongation at break but decreased the melt flow rate and the moisture content of the ternary alloy.