DETERMINATION OF THE TOUGHNESS OF SAMPLES DIRECTLY OBTAINED FROM POLYPROPYLENE PIPES

The toughness of polypropylene tubes for water transport was measured using specimens directly obtained from extruded pipes. The morphology of the crystalline phase, resulting from the extrusion process, was in vestigated through Small Angle Light Scattering Analysis. The crystall ine spherulite dimensions, shape, and distribution over the pipe thick ness were determined. Impact tests at various temperatures and microgr aph observations of fracture surface gave useful indications about the fracture mechanisms. The tests evidenced the influence of specimen th ickness and material morphology over the different crack propagation m odes.