Abstract

Conductive rubber based nanocomposites applicable as pressure sensors

Author(s): Omar A.Al-Hartomy, Ahmed A.Al-Ghamdi, Nikolay Dishovsky, Petrunka Malinova, Rashko Dimitrov, Farid El-Tantawy

This work reports on the preparation of composites based on different in chemical nature elastomers (natural rubber and siloxane) filled with different amounts of fillers (furnace carbon black, titaniumdiboride and hybrid combination of furnace carbon black and nanosized nickel powder) and investigation of the changes in their volume resistivity depending on applied pressure on the composites in the regions 0-35 kPa (low pressures) and 0-100 MPa (high pressures) to evaluate their pressure sensitive properties. It has been established that when applied pressure is higher than 10 ÌÐà (in the 0÷100 ÌÐà range) the volume resistivity of all composites studied depends slightly or almost does not depend on pressure no matter what the nature of the elastomer matrix and filler is. It means that the composites are not suitable for pressure sensors at high pressures. In the 0÷35 kÐà range all composites are sensitive to pressure changes. In most cases the character of the dependences is linear and reversible. The increase in filler concentration and pressure applied leads to a volume resistivity decrease, i.e. at low pressures some of the composites could be used as pressure sensors in orthopaedics and in other fields of medicine. The composites based on siloxane rubber and filled with carbon black are the most suitable for sensors of all studied.