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Recycled soda lime silica glass‐filled polytetrafluoroethylene composites were prepared for substrate application at microwave frequencies. Various volume fractions (0.05–0.25) of the filler were dispersed in the polytetrafluoroethylene matrix. The composites' dielectric, mechanical, and thermal properties were examined with respect to the filler content. X‐ray diffraction data established the phase structure of the polytetrafluoroethylene matrix and recycled soda lime silica glass. Scanning electron microscope micrographs revealed uniform filler distribution at lower recycled soda lime silica contents, while energy dispersive x‐ray analysis showed the purity of the composites. The tensile strength of the composites reduced from 13.5 MPa to 4.26 MPa, while the moisture absorption and density raised from 0.07 % and 2.195 g/cm3 to 0.19 % and 2.228 g/cm3 when the recycled soda lime silica filler volume fraction was adjusted from 0.05–0.25. The lowest coefficient of thermal expansion values was recorded at 0.25 % recycled soda lime silica volume fraction, which increased from 31.12 ppm/°C to 68.32 ppm/°C at 40 °C to 200 °C. At 0.05 filler volume fraction, the respective values of ϵ' ${\varepsilon{} { {^\prime}}}$ , tanδ ${tan\delta }$ and Td ${{T}_{d}}$ of the composites decreased from 2.20, 0.0017, and 29.69 ps to 2.15, 0.0015, and 29.35 ps in the 8.2 GHz–12.4 GHz range. [ABSTRACT FROM AUTHOR]

Glass ionomer cements (GIC) are produced through acid base reaction between calcium-fluoroaluminosilicate glass powder and polyacrylic acid (PAA). Soda lime silica glasses (SLS), mainly composed of silica (SiO2), have been utilized in this study as the source of SiO2 for synthesis of Ca-fluoroaluminosilicate glass. Therefore, the main objective of this study was to investigate the potential of SLS waste glass in producing GIC. Two glasses, GWX 1 (analytical grade SiO2) and GWX 2 (replacing SiO2 with waste SLS), were synthesized and then characterized using X-ray diffraction (XRD) and energy dispersive X-ray (EDX). Synthesized glasses were then used to produce GIC, in which the properties were characterized using Fourier transform infrared spectroscopy (FT-IR) and compressive test (from 1 to 28 days). XRD results showed that amorphous glass was produced by using SLS waste glass (GWX 2), which is similar to glass produced using analytical grade SiO2 (GWX 1). Results from FT-IR showed that the setting reaction of GWX 2 cements is slower compared to cement GWX 1. Compressive strengths for GWX 1 cements reached up to 76MPa at 28 days, whereas GWX 2 cements showed a slightly higher value, which is 80MPa. [ABSTRACT FROM AUTHOR]