title: Contact angles of submillimeter particles: connecting wettability to nanoscale surface topography.
abstract: A method is presented for the measurement of contact angles of particles in the size range 100-1000 microm, using an optical microscope. This method is used to characterize the wettability of polyethylene particles produced in a gas-phase polymerization process. The as-polymerized particles are shown to be significantly more hydrophobic than melt-processed polyethylene materials. The surface structure of the particles is examined with scanning electron microscopy, and the increased hydrophobicity of the as-polymerized particles is attributed to the nanoscale texture of the particle surfaces.
authors.affiliation: Department of Chemical Engineering, Case Western Reserve University, Cleveland, Ohio 44106, USA.
authors.forename: Keith M
authors.initials: KM
authors.lastname: Forward
authors.forename: Amanda L
authors.initials: AL
authors.lastname: Moster
authors.forename: Daniel K
authors.initials: DK
authors.lastname: Schwartz
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Lacks