Wettability of CaCO3 surfaces

The wettability of calcium carbonate, an important parameter in the evaluat ion of the interaction characteristics of materials used in conservation, w as examined by measurements with the Wilhelmy plate technique. Heterogeneou s surfaces consisting of glass and calcium carbonate were examined. Stable calcium carbonate layers were deposited on microscope glass slides using su persaturated solutions in which the equimolar concentrations of total calci um and total carbonate used ranged between 0.1 and 0.4 M, over a pH range b etween 9 and 12 and temperature between 25 and 80 degrees C. In all cases a morphous calcium carbonate was deposited, the extent of surface coverage in creasing with increasing supersaturation and temperature. Higher surface co verage of the glass slides with calcium carbonate yielded lower contact ang les suggesting increased wettability of the heterogeneous surface. (C) 1999 Elsevier Science B.V. All rights reserved.