Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9817819 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2005 | 6 Pages |
Abstract
Film samples of two very pure polyolefins (low density polyethylene, LDPE and biaxially oriented polypropylene, BOPP) were surface-modified by two different methods, namely vacuum ultraviolet (VUV) irradiation with a Kr resonant lamp in low-pressure NH3 gas, and atmospheric pressure glow discharge (APGD) plasma treatment in pure N2 gas. Samples were then stored in air and the time-dependence of surface properties (the surface energy and chemical composition) was monitored using several complementary surface-sensitive techniques: contact angle goniometry (CAG), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). We show that the main mechanism responsible for hydrophobic recovery is the motion of polymer chains and chain segments, which governs an apparent “loss” of functional groups, within the first monolayers of the surface (â¼1Â nm). Finally, comparing BOPP samples modified by both techniques, we show that aging can be reduced by crosslinking near the surface, as illustrated by depth-sensing nano-indentation measurements.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
F. Truica-Marasescu, S. Guimond, P. Jedrzejowski, M.R. Wertheimer,