The Improvement of Compatibility in Glass Reinforced PA 6/PP Blends

This article deals with the properties of 30% w/w glass reinforced compatibilized blends of polypropylene (PP) and polyamide (PA6). Rheological properties (melt flow index and melt stability), mechanical properties (tensile strength, flexural strength and impact strength) of PA6/PP blends were investigated. The influence of potential compatibilisers (4,4,-diphenylmethanecarbodiimide (OCDI), 4,4’-diphenylmethanebismaleimide (BMI) and 2,2’-(1,4-phenylene)-bisoxazoline (BOX)) on the mechanical properties and thermal stability of unreinforced and glass reinforced polymer blends was investigated too. We tried to study the structure of the glass reinforced composites by mercury intrusion porosimetry. The influence of compatibilisers on the molecular weight of PA6 was studied hy GPC and the chemical structure of the blends was investigated by NMR and IR-spectroscopy. Addition of OCDI and BOX (chain extenders) preserves the product structure as they react with the active and carbonyl groups of PA6. BMI has the lower reactivity. Grafting of BMI to PP chains improves the compatibility in PA6/PP blends and increases PP adhesion to glass fibres.