Fabrication of photo-crosslinkable polymer/silica sol-gel hybrid thin films as versatile barrier films

Abstract

Versatile films composed of a photo-crosslinkable thiol-ene (ThE)/silica sol-gel hybrid nanocomposite were prepared using a two-step process. Tetrafunctional thiol and triene monomers were employed as precursors to generate a matrix polymer. Tetraethyl orthosilicate (TEOS) was incorporated as the silica source for the sol-gel process. A two-step process, sol-gel reaction followed by photocuring, resulted in uniform and transparent hybrid thin films. The formation of homogeneous, mechanically stable, and optically transparent films was confirmed and the films were characterized by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses. The morphological properties of the films were assessed by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The thermal expansion of the obtained membrane films was examined by thermomechanical analysis (TMA). In addition, optical transmission and gas permeation were assessed for high-performance applications.