title: Elastic modulus of a polymer nanodroplet: theory and experiment.
abstract: We redevelop a theoretical model that, in conjunction with atomic force microscopy (AFM), can be used as a noninvasive method for determination of the elastic modulus of a polymer nanodroplet residing on a flat, rigid substrate. The model is a continuum theory that combines surface and elasticity theories for prediction of the droplet's elastic modulus, given experimental measurement of its adsorbed height. Utilization of AFM-measured heights for relevant droplets reported in the literature and from our own experiments illustrated the following: the significance of both surface and elasticity effects in determining a polymer droplet's spreading behavior; the extent of a continuum theory's validity as one approaches the nanoscale; and a droplet size effect on the elastic modulus.
authors.affiliation: Institute for Materials and Processes, School of Engineering, The University of Edinburgh, Edinburgh, United Kingdom. a.evangelopoulos@ed.ac.uk
authors.forename: Apostolos E A S
authors.initials: AE
authors.lastname: Evangelopoulos
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Glynos
authors.forename: Frédéric
authors.initials: F
authors.lastname: Madani-Grasset
authors.forename: Vasileios
authors.initials: V
authors.lastname: Koutsos