THE FORCE-AREA CURVE FOR A SPREAD SLIGHTLY SOLUBLE MONOLAYER (MYRISTIC ACID)

The pressure versus area curves for a spread myristic acid monolayer a re markedly affected by the compression velocities as becomes clear fr om the published results of K. Motomura, A. Shibata, M. Nakamura, and R. Matuura (J. Colloid Interface Sci. 29, 623, 1969). This is due to t he dissolution of spread molecules into the bulk solution. From these apparent Pi-A curves the thermodynamic Pi-A curve (without a phase tra nsition), where no diffusion is present, can be constructed in three d ifferent ways. A qualitative explanation for the different diffusion r elaxation times obtained by each approach is given. (C) 1995 Academic Press, Inc.