Comparative Study of Surface Morphology and Spectroscopic Analysis for Corona and Chromic Acid Treated Polyethylene Film for Water Based Ink Printing.

Polyethylene, Specially the LDPE is one of the most widely used thermoplastic in packaging industries, due to its low cost, broad range of properties like excellent moisture barrier and chemical resistance which are need for food packaging sectors. As mentioned above LDPE is most widely used plastic for packaging film applications but the major disadvantage is that the surface of the LDPE film is smooth and non polar also shows the lack of chemical functionality which is a requirement for adhesive bonding, hence surface preparation/modification become necessary. Often which adhesion properties increase of all the available methods to modify the polymer surface for enhancing adhesion properties, here in this study we have used Corona treatment and Chromic acid treatment to modify surface of LDPE film. The modification in surface due to the treatments were correlated by means of Fourier transformed infrared spectroscopy (FTIR) to determine the presence of polar species such as carbonyl, carboxyl and hydroxyl groups etc. The improvement in ink adhesion, both water based and solvent based inks was studied by standard Scotch tape adhesion test. Furthermore Surface property and Surface morphology was characterized by contact angle measurement and Scanning Electron Microscope (SEM). Surface energy and surface roughness can be directly correlated to the improvement in surface-related properties.