Investigation of the ceramifying process of modified silicone-silicate compositions

Glass frits were added into silicone-based composites with the aim to improve low temperature ceramification at elevated temperatures. The effect of glass frits on the properties of ceramic residue is investigated. Field emission scanning electron microscopy (FESEM), electron probe microchemical analysis (EPMA) and X-ray diffraction analysis (XRD) showed that glass frits reacted via a eutectic reaction with mica and silica. Electrical conductivity measurements at elevated temperatures showed a decline in volume resistivity with glass frit addition. It was concluded that increased conductivity is a result of ionic conduction of the glass phase produced by eutectic reactions between frits, silica and mica at high temperatures. Thermal mechanical analysis (TMA) was used to explore the dimensional changes of these composites during programmed heat treatment.