Low Thermal Conductivity Plaster – Perlite Microsphere Composites as Potential Thermal Insulation Materials in Building Construction

Abstract In the current study plaster − expanded perlite microsphere composites, were investigated regarding their thermal insulation properties. In this context commercially available plaster powder was mixed with expanded perlite microspheres, of various grain size distribution and bulk density, aiming the investigation of the effect of ultrafines in the aggregates on the mechanical properties of the composites. The mixing procedure resembles that of making plaster mortars, in building construction. Thermal conductivity of composites was found to be sizably lower than that of pure plaster, and was further decreased with increasing filler loading. Moreover, filler density seems to affect thermal insulation performance, at high loading concentrations. Slight increase of the mechanical properties was identified when aggregates include ultrafine particles. Thermal insulation performance experiments indicate that plaster − expanded perlite microsphere composites clearly exhibit better thermal insulation properties, in comparison to pure plaster. Overall, expanded plaster − expanded perlite microsphere composites seem to be efficient insulation materials for potential applications in buildings’ construction, toward reducing their energy footprint.