Nowadays, nanofillers are used to improve the numerous properties of the polymer. Incorporation of nanofiller in polymers often lead to boost the properties of resultant materials. Several researchers have devoted great attention to the surface modification of nanofillers by chemical or physical interaction. The nanofillers’ surface was stabilized by covalent attachment of polymer ligands. Some literature evidenced that the agglomeration of nanofiller can also be minimized by strengthening the interaction between the nanofillers with the polymer matrix, which leads to the formation of polymer nanocomposites. It is reported that the combination of well-dispersed and surface-treated nanofillers would yield excellent opportunities to engineer the thermal behavior of a wide range of nanocomposites. Several polymers have been utilized to develop polymer nanocomposites like PMMA, PPy-PVA, LDPE, etc., with various nanofillers to study the thermal and optical behavior. This chapter throws light on the influence of nanofillers (ZnO, TiO2 and ZrO) in the thermal and optical properties of Poly(pyridine-4-yl-methyl) methacrylate-co-butyl methacrylate.