Aging effects around the glass and melting transitions inpoly(dimethylsiloxane) visualized by resistance measurements

The process of aging in rubbers requires monitoring over long periods (days to years). To do so in nonconducting rubbers, small amounts of carbon-black particles were dispersed in a fractal network through the rubber matrix, to make the rubber conducting without modifying its properties. Continuous monitoring of the resistance reveals the structural changes around the glass and melting transitions and especially details about the hysteresis and aging processes. We illustrate the method for the semicrystalline polymer poly(dimethylsiloxane).