Composition Dependence and Optical Properties of Polymethyl Methacrylate/Alumina Nanocomposite in the IR Region Determined by Kramers-Kronig Relation

Abstract

The dependence of the IR optical properties of PMMA/Al 2 O 3 nanocomposite on the alumina content was investigated in the wavelength range of 3500-2800 cm − 1. The samples were prepared via emulsion polymerization technique using oleic acid as a coupling agent. Grafting density calculations were carried out by means of elemental analysis CHN to yield the best coupling agent content. FTIR analysis confirmed the existence of a chemical bond between aluminum oxide and oleic acid. The outcomes of XRD analyses showed the presence of cubic gamma aluminum oxide in the nanocomposite, in contrast to the amorphous nature of PMMA. TEM images showed the core-shell morphology of the particles other than pristine PMMA. Optical constants of the nanocomposite were calculated based on FTIR spectra and the Kramers-Kronig equations. The presence of nano alumina modified some of the optical indexes in IR region.