Effects of thermoplastic polyurethane (TPU) morphology on the electrical conductivity of TPU/carbon black (CB) composites
Haun Hiran Conrado (1), Suzuki Nina Yumi (2), Vidotti Suel Eric (3), Chinellato Anne Cristine (3)*
(1) Postgraduate Program in Materials Science and Engineering, Federal University of ABC - Santo André - Brazil, (2) Undergraduate education in Materials Engineering, Federal University of ABC - UFABC - Santo André - Brazil, (3) CECS - Federal University of ABC - UFABC - Santo André - Brazil
This work aimed to study the effect of thermoplastic polyurethane (TPU) morphology / structure on the electrical conductivity of TPU / carbon black (NF) composites. For this purpose, TPU / NF composites with different NF concentrations were prepared in a single screw extruder using two TPUs with different hardnesses (Shore A 90 and 72). Regarding the morphology of the TPU, the analysis of DSC, TGA, and scanning electron microscopy indicate that the higher presence of rigid segments favors the electrical conductivity of the composite. This assumption can be considered because materials prepared under the same processing conditions and with the same amounts of carbon black had different conductivities. This is probably due to the fact that NF interacts preferentially with the rigid segments of the TPU structure. Thermal aging tests did not show considerable changes in the electrical conductivity of the composite, although some morphological changes were observed.