Effect of polymer molecular weight variations on PZT slip for tape casting

Ceramic slips were formulated based on the PZT/plasticized-polymer system. The total volume of polymer in slip was held constant, while the relative amount of plasticizer and binder was varied. Experiments were performed to elucidate the effects of the polymer molecular weight and its end-to-end distance on the properties of green sheet as well as on the rheological properties of casting slips. Tapes(thickness=200 μm) were cast from these slips and their properties were evaluated. The properties of polymers such as their average molecular weight(end-to-end distance) and molecular weight distribution had a dramatic effect both on slip rheology and green sheet properties. The optimum ratio of PVB to DPB for the PZT tape casting process was 75 : 25. The properties of green sheet agreed well to viscosity behavior of PZT slip. And the burn-out behaviors of each green sheet were quite different.