Joule heating treatments of conductive butyl rubber/ceramic superconductor composites: a new way for improving the stability and reproducibility?

The present paper describes the effect of superconductors on the sintering process, apparent cross-linking density, sintering factor, hardness and volume fraction of butyl rubber (IIR) composites. Electrical conductivity and I-V characteristics at various processing conditions of IIR with different concentrations of superconductor were measured. The stability and reproducibility of IIR composites were tested. Also, the conduction mechanism of electrical conductivity is discussed. Specific heat and the amount of heat transferred by radiation and convection were calculated via the proposed model and calorimetry as a function of superconductor content. It was found that superconductor accelerates the driving force during the sintering process and the characteristic time constant during sintering decreases while the sintering factor, the apparent cross-linking density, hardness and volume fraction of rubber increases as the content of superconductor increases. In addition, it was proved that the superconductor and Joule heating effect improves the electrical and thermal properties of IIR. (C) 2001 Elsevier Science Ltd. All rights reserved.