Contact Angle Studies in XLPE Hybrid Nanocomposites with Inorganic Nanofillers

Wetting properties and surface energy characteristics of cross-linked polyethylene (XLPE) with different nanofillers (such as Al2O3, SiO2, TiO2, and clay) were studied using contact angle measurements with water and dimethyl sulfoxide (DMSO) as solvents. Similar trend of variation of contact angle was found for both the kinds of systems. In nanocomposites, the high packing density of the macromolecules on the super molecular level (with marked ordering even in quasi-amorphous regions) create steric and kinetic hindrances for penetration of solvent molecules, which may result in high degree of solvent resistance, confirmed by the transition of the material from wetting region (for neat XLPE) to a non- wetting region (for nanocomposites). Results of contact angle studies have been correlated with the morphology and microstructure development in each system by electron microscopy.