A heat-resistant preceramic polymer with broad working temperature range for silicon carbide joining

A room temperature curable heat-resistant adhesive with broad working temperature range was prepared through organic and inorganic modification. The preceramic polymethylsiloxane showed low bonding strength for silicon carbide from 400 degrees C to 600 degrees C because of the decomposition of polymer network. So the modification with epoxy resin was used to generate strong blending and copolymerization network which decomposed at higher temperature over 500 degrees C. The ceramization of active fillers and preceramic polymer compensated the bonding strength with rising temperature, thus eliminating the weak stage from 400 degrees C to 600 degrees C. The modification with fillers greatly improved its bonding strength at high temperature over 1000 degrees C. Consequently, the modified adhesive exhibited outstanding bonding strength tested at room temperature between 9.29 +/- 0.56 MPa and 37.28 +/- 1.33 MPa after heat-treatment from 25 degrees C to 1500 degrees C and the bonding strength directly tested at the temperature from 25 degrees C to 800 degrees C over 8.21 +/- 0.40 MPa. The adhesive shows the potential to extend the application for engineering ceramic joining.