Structure and mechanical properties of blends of an amorphous polyamide and a liquid crystalline polymer

The structure and the mechanical properties of blends of an amorphous polyamide (PA) and a thermotropic copoly(ester-amide) (VB) obtained both by direct injection molding (DI) and also by extrusion and subsequent injection molding (EI) have been studied. Besides the usual fibrillar morphology of the skin, fibrillation was also observed in the core of most of the blends. The important synergisms in the modulus of elasticity (20% positive deviations in both blends with 30% and 40% VB contents) and also in the tensile strength (30% and 55% positive deviations in the EI blends at the same compositions) were obtained without the presence of compatibilizer.