Cellular ceramics processed by paraffin emulsified suspensions with collagen consolidation

Abstract

Cellular ceramics were prepared by emulsification of liquid paraffin in aqueous alumina suspensions, with sodium lauryl sulphate as a surfactant, and with or without collagen as a suspension shape stabilizer. Solidification of the paraffin droplets halts coarsening of this dispersed phase, and collagen-based gelling facilitates drying without coarsening of organic droplets and their subsequent thermal elimination without collapse of the green ceramic skeleton. Firing at 1550 degrees C, for 2 h, yielded the expected cellular ceramics. Cellular cell sizes and other microstructural features were changed by modifications in emulsification, namely addition of collagen and additions of defloculant, to adjust viscosity. These factors also play important effects on interconnectivity of cells. (C) 2013 Elsevier B.V. All rights reserved.