Characterization of SiO_2/ LDPE Composite Barrier Films

Silicon dioxide, SiO_2 has been deposited on Low-Density Polyethylene (LDPE) surface using Physical Vapor Deposition (PVD) technique. Several thickness films (200, 500, 700 and 1500 nm) were prepared. The obtained films were identified and characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV-VIS) and atomic force microscopy (AFM). At specific coating thickness, far infrared radiation transmittance was prohibited while the ultraviolet–visible transmittance is allowed and that will be explained in details. The morphological characterization emphasized the homogeneity of the prepared films surface and the uniform of grains size with the following order 500, 700, 450 and 525 nm as observed by AFM. Optical measurements show that, the coated films prevent the transmission of IR radiation near 10μm and allow UV-VIS transmission during sun-shining time.