Polymer nanocomposites (PNCs) play a fundamental role in the design of novel materials since they offer a chance to combine the unique properties of nanoparticles with the beneficial advantages offered by polymers, while yielding potential performance well beyond that of each individual component 1,2. Recently, the embedding of inorganic nanoparticles in organic polymers has received considerable attention, because organic-inorganic nanocomposites play an important role to improve the physical properties of classical polymers 3. Polymer systems are quite significant due to their applicable properties which include; simple production, low cost, and lightweight 4. One of the most important techniques to enhance their properties is the loading of polymers with nanoparticles. With this, polymer properties can be improved while preserving suitable properties 5. Improvements in properties can often occur even at comparatively small filler concentrations 6.
Polystyrene (PS) with the chemical formula (C8H 8) n is the most widely known and used polymer in both industry and everyday life. It is a synthetic hydrophobic polymer. It is considered to be an excellent host material for composites. It has attracted significant attention due to its superior properties such as rigidity, perfect electrical insulation properties, low water absorption, low cost, and ease of processing, which are fundamental for numerous industrial applications 7, 8. The addition of inorganic nanoparticles to polymers allows the modification of the physical polymer properties as well as the achievement of new properties for the polymer matrix. Aluminum oxide nanoparticles Al2O3 nanoparticles received great attention for the development of polymer–nanocomposites during recent years due to its particular characteristics such as high chemical stability, high luminous transmittance, and intensive ultraviolet.
Moreover, Al2O3 nanoparticles in polymeric materials are further applied as surface coatings 9, 10. Although various studies investigated the properties of polymer nanocomposites as a function of nanosized fillers in PS 11, 12, none of these focused on systems with Al2O3 embedded in PS. However, studying the structure of polymers that are embedded with nanoparticles is important to describe the change in crystallinity and lattice parameters after introducing the nanofiller in the polymer matrix.
These techniques are not only beneficial for the clarification of changing confirmation due to the motion of individual molecules of the polymer, but also explain the behavior of structure formation 13.The UV-visible analysis of polymer filled with inorganic nanoparticles is an advantageous technique to investigate the transitions of electrons and for obtaining knowledge about the band structure, the optical activation energy and the refractive index of the polymeric materials under consideration. Investigation of the optical constants such as refractive index, real and imaginary part of complex dielectric and optical conductivity of polymer films is important in the fabrication of new materials. Studying the optical parameter of the materials leads to their benefits in several industrial applications 14. Refractive index is important optical parameters for designing prisms. Optical windows and optical fibers, besides the changes of the refractive index of the material are essential for controlling optical behavior of the polymeric material 15.
The irradiation of polymer films can induce different modifications in both structural and optical behavior. Molecular chain scission, intermolecular cross-linking and the formation of C=C are some of the structural changes than can occur in the irradiated polymer, all of which modify the physical properties of the material 16, 17. As we mentioned above, several studies investigated the properties of the polymer as a function of nanosized fillers in PS, but none of them are focused on systems with Al2O3 embedded in PS. The novelty of our current approach is to prepare a new material of polystyrene filled with different concentrations of Al2O3 nanoparticles which could be used in the applications of surface coating and as anticorrosion material.
Thus, we aim to investigate the influence of Al2O3 nanoparticle additives and gamma irradiation on the structure and optical properties of PS. This work objective is not only to give proof of the physical and chemical modifications in the polymer under consideration but also to determine the feasibility of boosting its characteristic features to make it much applicable.