Ultra-high molecular-weight polyethylene (UHMWPE) and linear polyethylene (LPE) were treated by low keV H2+, He+ and N2+ ion beams up to 2×1017 ions cm-2, and the chemical changes induced in the modified surface layer were studied by FT-IR and XPS. The concentration of vinyl groups decreased, while that of the trans-vinylene, trans-trans diene, methyl and carbonyl groups increased. The degree of polymer crystallinity was reduced. Changes in the valence band, in the C KVV Auger peak and in the plasmon loss splitting of the Cls peak indicated the occurrence of graphitisation. On treatment by N2+ ions - in addition to the above changes - nitrogen incorporation took place. The N-content of the surface layer reached a saturation value of ∼11 at% at ∼1017 ions cm-2. The Nls peak was decomposed to three components at 398.3, 400 and ∼402.8 eV, which were assigned to nitrogen in C-N, C=N (imine), and C=N with delocalised nonbonding electron pair on N, respectively.
|Number of pages||5|
|Journal||Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms|
|Publication status||Published - Jan 1 1999|
- Ion beam
- Surface structure
ASJC Scopus subject areas
- Nuclear and High Energy Physics