INFLUENCE OF THE ADDITION OF PORE FOAMING AGENT ON MECHANICAL AND THERMAL PROPERTIES OF PORCELAIN TILES

In this work, the effect of pore foaming agents (polymethyl methacrylate, PMMA) on the densification characteristics as well as mechanical and thermal properties of sintered porcelain samples was investigated. The influence of the PMMA content (0 -20 wt. %) and sintering temperature (1000 -1300 C) were also studied. The result showed that the incorporation of PMMA in porcelain bodies led to a decrease in the density, while the porosity increased with an increase in sintering temperature. At 1300 C, the bulk density and porosity of porous porcelain samples with PMMA additions (5 -20 wt. %) were in the range of 1.91 -2.23 gcm -3 and 1.3 -17.2 %, respectively. The flexural strength of the porous porcelain samples prepared by adding 5 -20 wt. % PMMA and sintering at 1300 C was in a range of 36 -56 MPa, which is higher than the minimum strength values (35 MPa) of ISO 13006 standard for ceramic tiles. The thermal conductivity of porous porcelain is a function of the sintering temperatures. The increase in sintering temperature had a positive effect on the thermal conductivity of ceramic samples, because the thermal conductivity decreased significantly with increasing porosity levels. The addition of 20 wt. % PMMA in porcelain samples sintered at 1300 C reduced the thermal conductivity up to 34 % while maintaining acceptable flexural strength values (~ 36 MPa). Thus, it is possible to use these porcelain samples as ceramic tiles in order to enhance the thermal resistance of building materials.