Stability of thermo-sensitive properties of carbon-black/styrene-butadiene-rubber composite membranes

摘要: Conducting composite membranes were prepared by using styrene butadiene rubber as matrices and incorporating carbon blacks some organic crystals (2,6-di-tert-butyl-4-methyl phenol, BMP). A number of exhibited a thermo-sensitive property which corresponded to positive temperature coefficient (PTC) effect. Their DSC thermograms x-ray patterns indicated that there no significant changes in the structure although these subjected discontinuous repeated thermal cycle measurements more than 100 runs. The switching characteristic PTC intensity showed satisfyingly reproducible stability. It was also found ageing treatment could remarkably influence conductive properties membranes. When thermally aged at 90 or °C for various times up 480 h, essential resistivity observed their still effectively maintained. However, when exposed an elevated higher over time intervals from 24 detected original almost totally disappear depending on time. obtained results revealed maintain stability long term environment lower °C.