Polycarbonate/poly(methyl methacrylate)/silica aerogel blend composites for advanced transparent thermal insulations: Mechanical, thermal, and optical studies

Abstract

AbstractUsing transparent thermal insulators, which are low heat conductors and good light transmitters, is a brilliant idea to preserve heat energy. In this regard, silica aerogels (SAs) have attracted immense attention these days because of their unique nanoporous networks, consisting of connective silica nanoparticles and high‐volume nanopores. The present study investigates the influence of incorporating 3 and 5 phr SAs on the mechanical properties, thermal conductivity (TC), and optical characteristics of polycarbonate/poly(methyl methacrylate) (PC/PMMA) (75/25, 50/50, and 25/75 w/w) blends. The scanning electron microscopy studies indicated that the PC/PMMA/SA (25/75/3) composite has the best dispersion. The highest improvements in tensile strength and Young's modulus were observed for the PC/PMMA/SA (75/25/5) composite. In addition, incorporating the SA resulted in a reduction in the impact strength of all the blends. The lowest TC was observed for the PC/PMMA/SA (75/25/5) blend composite. The TC results were compared with the data predicted by the Agari, Russell, Maxwell–Eucken, and Bruggeman models. It was found that the Agari logarithmic model has the best agreement with the experimental data. Except for PC, PMMA, PC/PMMA (25/75), and PC/PMMA/SA (25/75/3), no other samples showed optical transmittance. On average, PC/PMMA/SA (25/75/3) had 13% more light absorption than PC/PMMA (25/75).