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

• Successful production of mechanically stable and optically transparent thiol-ene/silica sol–gel hybrid thin films.
• Efficient use of sol–gel reaction and photopolymerization by UV irradiation for the preparation of high performance thin film materials.
• Feasible control over microstructure of thin films by the introduction of silica network using sol–gel reaction.
• Control over gas permeabilities of the obtained versatile thin barrier films.

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.

Mechanically stable and optically transparent thiol-ene/silica sol–gel hybrid thin films were successfully produced and their performance as versatile barrier was assessed.Figure optionsDownload as PowerPoint slide