| 초록 |
Up to now, polyurethane / carbon black / stearic acid showed the lowest critical transformation temperature (Tc) of 70℃ among polymeric PTC composites. This is due to the expansion in volume of stearic acid. In this study, palmitic acid and myristic acid which shows lower Tc than stearic acid were used to make the composite and the effect of those on the Tc. Programmable oven and digital multimeter were used to measure the temperature dependence of resistivity.Melting point of palmitic acid, myristic acid and Tc of the composite were measured by DSC. From the SEM images of composites, the degree of dispersion will be discussed. |
