title: Study of the morphology of the three-phase contact line and its evolution by morphological examination after droplet evaporation of aqueous polymer solutions.
abstract: The local morphology and its evolution of an air-liquid-solid three-phase contact line was studied on the homogeneous surfaces of homopolymer of polystyrene (PS) and poly(methyl methacrylate) (PMMA) and the nanostructured surface of diblock copolymer of PS- b-PMMA by the approach of the morphological study of the residual solid after droplet evaporation of water-soluble polymers such as poly(vinylpyrrolidone) (PVP) and poly(acrylic acid). The observation by atomic force microscopy discovered the stripelike "button-and-ribbon" structure of the precipitated polymer solute along the moving direction of the contact line. On the surface of PS- b-PMMA, the morphology of PVP has a close correlation with the nanostructure of PS- b-PMMA. The results exhibit the local morphology of the contact line and its evolution, revealing its pinning and depinning processes on the nanometer scale.
authors.affiliation: Beijing National Laboratory of Molecular Science, State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Sciences and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.forename: Cunfu
authors.initials: C
authors.lastname: Zhang
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhao
authors.forename: Yingxi
authors.initials: Y
authors.lastname: Zhu