Portal de Periódicos da CAPES

Surface modification of polyethylene by low keV ion beams

1999; Elsevier BV; Volume: 148; Issue: 1-4 Linguagem: Inglês

10.1016/s0168-583x(98)00833-7

1872-9584

A. Tóth, Toby D. M. Bell, I. Bertóti, M. Mohai, B. Zelei,

Diamond and Carbon-based Materials Research

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 C1s 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 N1s 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.