DIRECT MEASUREMENT OF REPULSIVE VAN-DER-WAALS INTERACTIONS USING AN ATOMIC-FORCE MICROSCOPE

Authors
MILLING A MULVANEY P LARSON I
Citation
A. Milling et al., DIRECT MEASUREMENT OF REPULSIVE VAN-DER-WAALS INTERACTIONS USING AN ATOMIC-FORCE MICROSCOPE, Journal of colloid and interface science, 180(2), 1996, pp. 460-465
Citations number
21
Categorie Soggetti
Chemistry Physical
Journal title
Journal of colloid and interface science → ACNP
ISSN journal
00219797
Volume
180
Issue
2
Year of publication
1996
Pages
460 - 465
Database
ISI
SICI code
0021-9797(1996)180:2<460:DMORVI>2.0.ZU;2-7
Abstract
The forces of interaction between a flat poly(tetrafluoroethylene) (PT FE) surface and gold spheres (of radii 3-8 mu m) were measured as a fu nction of apparent surface separation for different intervening media, For air, fluorinated alkanes, and polar liquids the interaction betwe en the surfaces was found to be attractive, With intervening liquids o f low-polarity the interaction was found to be repulsive, This repulsi on is attributed to a negative composite Hamaker coefficient leading t o van der Waals repulsion. (C) 1996 Academic Press, Inc.