# X-Ray Reflectivity of a Polymer Monolayer at the Water/Vapor Interface

 Title: X-Ray Reflectivity of a Polymer Monolayer at the Water/Vapor Interface Author: Schlossman, M. L.; Schwartz, D. K.; Kawamoto, E. H.; Kellogg, G. J.; Pershan, Peter S.; Kim, M. W.; Chung, T. C. Note: Order does not necessarily reflect citation order of authors. Citation: Schlossman, M. L., D. K. Schwartz, E. H. Kawamoto, G. J. Kellogg, Peter S. Pershan, M. W. Kim, and T. C. Chung. 1991. X-ray reflectivity of a polymer monolayer at the water/vapor interface. Journal of Physical Chemistry 95(17): 6628-6632. Access Status: Full text of the requested work is not available in DASH at this time (“dark deposit”). For more information on dark deposits, see our FAQ. Full Text & Related Files: Scholossman_X-ray_JPC_1991.pdf (682.4Kb; PDF) Abstract: X-ray specular reflectivity from a monolayer of partially hydroxylated 1,2-polybutadiene (50% butyl alcohol random substitution) at the water/vapor interface was measured from below the critical wavevector for water, 0.0217 Å$$^{-1}$$, to $$Q_z$$ $$\cong$$ 0.6 Å$$^{-1}$$ (where $$Q_z$$ is the transferred momentum normal to the interface). The sample was prepared on a Langmuir trough, and measurements were made at five different surface densities in the high-pressure, or saturated, region of the isotherm. The measured reflectivity is interpreted to obtain a profile of the average electron density p(z) as a function of distance z along the surface normal. The profile has a local maximum that is approximately 10% larger than the electron density in bulk crystalline 1,2-polybutadiene. At the highest pressures the width of the liquid/vapor interface is $$\sim$$ 10% larger than the value calculated from thermal capillary waves using in situ measurements of the surface tension; however, for smaller pressures the measured and calculated values agree. Published Version: http://dx.doi.org/10.1021/j100170a046 Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:10357569 Downloads of this work: