Bandgap Engineering and Optical Characterizations of Filler Reinforced PMMA Composite Thin Films

Polymeric composite (PC) materials are multifarious materials widely used in almost all industries due to their fascinating properties of being flexible, lightweight, durable, costeffective, and easy mass fabrication in a variety of shapes and sizes. Furthermore, the thermophysical properties of these polymeric materials can be further enhanced by the addition of an appropriate amount of organic or inorganic filler. Their high refractive index renders them to be used as components in the manufacturing of optoelectronic devices and hence certain optoelectronic parameters can be tailor-made by insertion of an appropriate filler in the host polymer. PMMA is one such versatile polymer with interesting optical properties, which can be further tuned up with filler enforcement for desired applications. This review deals with such organic and inorganic filler-doped PMMA composites with enhanced optical properties. Initially, the authors throw light on general physical and chemical properties of PMMA and its suitability to incorporate various fillers and the varied approaches of PMMA filler interactions. The review addresses briefly the various techniques of synthesis and optical characterisation of these PMMA-based PC. Further it attempts to summarize the underlying theories and concepts that construe the correlation between structure and optical parameters. The introduction of filler to bring a change in optical behaviour as desired is a challenging one. Hence authors have included not only the present state of art of these materials and the challenges thrown but also how the researchers are aiming to mitigate them in future.

Keywords: Absorption coefficient, Band gap energy, Extinction coefficient, Electrical resistivity, Finesse coefficient, High-frequency dielectric constant, Kramer’s-Kronig’s relation, Localized charge density value, Optical mobility, Oscillator strength, Optical conductivity, Organic and inorganic nanoparticles, Polymethyl methacrylate (PMMA), Polymer nanocomposites.