PA 6/EPDM blends for electrical insulations. Preliminary characterization

Electrical insulations must have certain characteristics that recommend them for long term service. Apart from electrical features, preparation and mechanical characterization are the former steps for the development of peculiar materials. The present paper concerns the preparation and characterization of PA6/EPDM blends, whose formulations consist of the both polymers on four relative concentrations: 100/0, 90/10, 80/20 and 70/30. They were mixed in a plastograph, which ensures the material homogeneity. After preparation of chips and plates by specific thermal regime, they were subjected to several tests for detailed characterization of endurance. The mechanical behavior is characterized by tensile strength and compression resistance, which have proved the contribution of elastomer loading on the material plasticity. The X-ray diffraction and the SEM analysis demonstrated that the increase in the EPDM concentration the crystallinity level decreases, so that the toughening of polyamide by elastomer becomes effective during material manufacture. The comparison of thermal stability and the contribution of each blended components is presented based on nonisothermal chemiluminescence. Oxidation onset temperature is dropped down as the EPDM content growths. The blend endurances were evaluated starting from the ageing data obtained at three temperatures with corresponding degradation time according with CEI regulations. The present results highlight the possibility of the manufacture of cable insulation layers. The next stage of research will be devoted to electrical characterization.