Polymethyl methacrylate based open-cell porous plastics for high-pressure ceramic casting

The aim of the present study is to investigate the microstructure-property relation in polymethyl methacrylate (PMMA)-based porous mould materials used for high-pressure casting of ceramic articles. For this purpose, porous plastic materials were produced by the polymerization of water-in-oil emulsions with various compositions of emulsion constituents and particle sizes of the filler PMMA beads. Pore morphology, porosity and water permeability of the materials were measured. The compressive stress-strain behavior, collapse stress and elastic modulus values of the macroporous materials were determined by performing compressive mechanical testing. Fracture toughness values of the materials were also measured using the single-edge notched bending method. The results showed that the concentration of emulsion constituents and PMMA bead sizes has significant effects on the pore morphology, porosity, water permeability and mechanical properties of the porous plastics. (C) 2004 Elsevier B.V. All rights reserved.