Force-distance curves by AFM

Adhesion forces in liquid media: Effect of surface topography and wettability

“…Two UHMWPE samples with different roughness but similar wettability were tested. For the sample of lower roughness the adhesion forces measured in air were much stronger than those measured in water or in an aqueous solution, in agreement with previous results reported by other authors [20,21]. In contrast, the sample of higher roughness yielded adhesion forces of similar magnitude in air and in the polar liquids, which can be conveniently explained by the existence of nanobubbles at the aqueous solution-polyethylene interface.…”

Effect of the covalently linked fatty acid 18-MEA on the nanotribology of hair’s outermost surface

“…As a Wrst step and to investigate Wbres in their usual environment, AFM force-curves were obtained in air. Although adhesion measurements under these conditions are likely to be inXuenced by capillary forces (Cappella et al, 1997), chemical speciWcity is maintained (Sedin and Rowlen, 2000). Indeed, the mean adhesion forces for the MSUD hair sample were markedly reduced compared to those obtained for hair from the MSUD unaVected child (F D 48 and 83 nN, respectively, p < 0.05; Fig.…”

New insights into the nature of the wool fibre surface

“…There are a number of excellent articles and reviews in this area (Cappella and Dietler, 1999;Frisbie et al, 1994;Green et al, 2002;Heinz and Hoh, 1999;Leggett, 2003;Noy et al, 1997), covering both adhesion and friction and the use of standard and chemically modified tips.…”