The volume resistivity ( v ) of natural rubber (NR) and nitrile butadiene rubber (NBR)-based composites filled with different amounts of titanium diboride (TiB 2 ) decreases with increasing filler concentration. Volume resistivity decreases with increasing pressure and temperature and there is no hysteresis loop formed. The conduction mechanism of the composites is interpreted by calculation of the activation energy (E a ) and hopping energy (E h ). The defined electrical properties classify the investigated samples as polymer composite semiconductors. The possibilities for real application of these composites as linear thermistors and transducers in pressure sensors are studied.
SiC-and B 4 C-filled NBR rubber composites were prepared with various volume fractions of filler by a conventional roll-mill method. The morphological structures of the NBR-SiC and NBR-B 4 C composites were analyzed by scanning electron microscopy. The dependence of roomtemperature volume resistivity (r v ) on the concentration of filler in the two systems was studied. In addition, variation in the number of current carriers (n), mobility carriers (m), dielectric constant (e), and dielectric loss factor (tan d) on filler concentration in the two systems were investigated in detail. The applicability of composites as negative temperature coefficient (NTCR) linear thermistors was studied by the dependence of volume resistivity on temperature. The resistivity showed negative temperature dependence and changed linearly with temperature parallel. The conduction mechanism of the conductivity of the two composites was analyzed in terms of the computed activation energy and hopping energy. Change in volume resistivity as a function of frequency for the two systems was also investigated. Finally, the dependence of volume resistivity on applied pressure and possible real applications of these composites as transducers in pressure sensors were also studied.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.