Polymer Science Faculty Research

Title

Direct Measurement of Acid-Base Interaction Energy at Solid Interfaces

Document Type

Article

Publication Date

11-8-2010

Abstract

We have studied acid-base interactions at solid-liquid and solid-solid interfaces using interface-sensitive sum frequency generation (SFG) spectroscopy. The shift of the sapphire hydroxyl peak in contact with several polar and nonpolar liquids and polymers was used to determine the interaction energy. The trend in the interaction energies cannot be explained by measuring only water contact angles. Molecular rearrangements at the sapphire interface, to maximize the interaction of the acid-base groups, play a dominant role, and these effects are not accounted for in the current theoretical models. These results provide important insights into understanding adhesion, friction, and wetting on solid interfaces.

Publication Title

Langmuir

Volume

26

Issue

23

First Page

17804

Last Page

17807