Evaluation of Chemical Properties of Polymethylmethacrylate in Two Different Media by Using Ultraviolet-Visible Spectroscopy

Abstract

Aim: The aim of this study was to evaluate the effect of concentration of chlorine on the polymethylmethacrylate and the influence of chemical properties of polymethylmethacrylate using ultraviolet-visible spectroscopy.Materials and methods: A total of 30 acrylic blocks of dimensions 65X 13X 3 mm as per the specification of ASTM [American standard for testing materials] were made in heat cure denture base resin to evaluate the effect of chlorine on polymethylmethacrylate. 30 samples were divided into 3 groups of 10 samples in each. Group, I was stored in artificial saliva which acts as a control group, Group II was stored in a 3ppm concentration of chlorine, and Group III was stored in a 100ppm concentration of chlorine.Results: Ultraviolet rays are passed into the sample, the results are obtained on a graph with a wavelength in nanometer on the X-axis and the percentage of reflectance on the Y-axis. If an organic compound absorbs ultraviolet radiation, it means that the compound contains carbonyl or conjugated double bonds3. Since polymethylmethacrylate absorbs ultraviolet rays, the existence of these bonds is confirmed in the graph.Conclusion: Within the limitations of the study it was concluded that the effect of chlorine on polymethylmethacrylate can react over the conjugated bond or carbonyl group at higher concentrations, whereas the action of chlorine is negligible at a lower concentrations.