The Effect of GGBFS, Quartz Flour, Micro-Calcite, and Their Combinations on the Structure and Properties of Polymer Concrete

This research aims to develop new types of polymer concrete composites. The main objective of the work was to investigate the influence of various types of mineral fillers (ground granulated blast-furnace slag (GGBFS), quartz flour (QF), micro-calcite (MC)) and their combinations on the properties of polymer concrete (PC) and to develop new effective PC compositions. An optimal PC composition was developed and seven series of experimental PC samples with different types of mineral fillers were manufactured: 1PC (GGBFS); 2PC (QF); 3PC (MC); 4PC (GGBFS + QF); 5PC (GGBFS + MC); 6PC (QF + MC); 7PC (GGBFS + QF + MC). The following parameters were measured: density, compressive strength, water absorption, and thermal conductivity. Scanning electron microscopy was used to assess the PC microstructure. To quantitatively evaluate the significance and influence of the mineral filler type on the PC properties, an analysis of variance was performed. The experimental results showed that the mineral fillers GGBFS, QF and MC and their combinations affect the properties of PC, especially its strength. The composition of 5PC turned out to be optimal: epoxy resin 15%; hardener 1.5%; plasticizer 1.5%; quartz sand 30%; crushed granite 30%; GGBFS 11%; MC 11%. Polymer concrete of composition 5PC had a density of 2263 kg/m3, a maximum compressive strength of 103.8 MPa, a minimum water absorption of 0.25% and a thermal conductivity coefficient of 0.466 W/m·K. The PC of all compositions had similar morphology, with a uniform structure and a randomly distributed pore size ranging from 81.27 µm to 384.9 µm. Microcracks were predominantly concentrated at the phase boundaries and propagated through the polymer matrix, enveloping the filler grains. The study yielded effective composite materials that could potentially be used in mechanical engineering as well as in industrial and civil construction, following durability testing and the determination of the full range of required properties.