Gasous hole closing in a polymer Langmuir monolayer.
The hole-closing phenomenon is studied in a polymer Langmuir film with coexisting gaseous and liquid phases both as a test of hydrodynamic theories of a two-dimensional fluid embedded in a three-dimensional one and as a means to accurately determine line tension, an important parameter determining size, shape, and dynamics within these and other membrane model systems. The hole-closing curve consists of both a universal linear regime and a history-dependent nonlinear one. Improved experimental technique allows us to explore the origin of the nonlinear regime. The linear regime confirms previous theoretical work and yields a value lambda = (0.69 +/- 0.02) pN for the line tension of the boundary between the gaseous and liquid phases. The observed hole closing also demonstrates that the two-dimensional polymer gas must be taken as having a small, probably negligible elasticity, so that line-tension measurements assuming that both phases are incompressible should be re-evaluated.
Zou
Lu
L
Department of Physics, Kent State University, Kent, Ohio 44242, USA.
Bernoff
Andrew J
AJ
Mann
J Adin
JA
Alexander
James C
JC
Mann
Elizabeth K
EK
D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D005740:Gases / Q000737:chemistry*; D006358:Hot Temperature; D007834:Lasers; D045423:Microbubbles; D011312:Pressure
D004129:Dimethylpolysiloxanes; D005740:Gases; C013830:baysilon