Advanced processing of lead titanate-polyimide composites for high temperature piezoelectric sensing

High performance polymer-ceramic composites are presented as promising candidates for high temperature piezoelectric sensing applications. lead-titanate (PT) ceramic particulate is incorporated into a polyetherimide polymer matrix, (PEI) at a specific volume fraction of 20% in the forms of 0-3 and quasi 1-3. A conventional dielectrophoretic structuring is used to induce chain like particle configuration, followed by curing the matrix to form free standing films. Poling process is perfomed at temperatures above the T_g of the partially imidized matrix and under high voltages subsequently. Free standing composites are imidized at 200 °C and 300 °C to form fully imidized films. The poled particulate composites tend to retain the original piezoelectric properties upon fully imidization. The structured composites show enhanced dielectric and piezoelectric properties compared to 0-3 composites.