Due to their unique chemical stability, high photo catalytic activity, high electric permittivity, and non-toxic nature, metal oxide nanoparticles are used in a wide range of optical, electrical, electronic, biomedical, environmental, and catalytic devices. The current research is focused on developing a nanocomposite of polymethyl methacrylate and magnesium oxide by first synthesising MgO nanoparticles and then treating them with the polymer. Infrared spectrophotometer for determining functional groups, thermogravimetric and differential thermal analyzers for determining thermal stability, scanning electron microscopy for morphology and refractometer, and so on have all been used to characterise the synthesised PMMA-MgO nanoparticle composite. In our research for new uses, we found that adding MgO to PMMA speeds up the reaction and cuts the synthesis time in half, from 40 minutes to 15 minutes. The role of MgO as catalysts has thus been established.