Optical and physical properties of infrared-exposed-PMMA/zircon composites

Poly(methyl methacrylate) (PMMA) with ZrSiO₄ (zircon)-filler composites were synthesized and their physical properties after infrared (IR) exposure was investigated. The zircon filler concentrations were 0, 0.5, and 1 wt%. The infrared exposures were 50 and 150 lx. The crystal and molecular structures of the unexposed and exposed samples were investigated using x-ray diffraction (XRD) and Fourier-transform Infrared (FTIR) spectroscopy. At the same time, the thermo-mechanical and optical properties were examined using dynamic mechanical analysis (DMA) and UV–Vis spectroscopy instruments, respectively. No significant XRD crystal structure changes were observed, but the IR molecular structure data showed the breaking of PMMA bonds. The zircon filler successfully reduced the number of PMMA bonds breaking. Generally, IR exposure degrades the thermo-mechanical properties of PMMA, but the presence of zircon filler improved them. The IR exposure also increased the absorption in UV and visible regions but reduced the E_g values.