Now showing items 1-10 of 10

    • The Beads-on-String Structure of Viscoelastic Threads 

      Clasen, Christian; Eggers, Jens; Fontelos, Marco A.; Li, Jie; McKinley, Gareth H. (2007-01-23)
      By adding minute concentrations of a high molecular weight polymer, liquid jets or bridges collapsing under the action of surface tension develop a characteristic shape of uniform threads connecting spherical uid drops. ...
    • Drop Formation and Breakup of Low Viscosity Elastic Fluids: Effects of Molecular Weight and Concentration 

      Tirtaatmadja, Viyada; McKinley, Gareth H.; Cooper-White, Justin J. (2007-01-23)
      The dynamics of drop formation and pinch-off have been investigated for a series of low viscosity elastic fluids possessing similar shear viscosities, but differing substantially in elastic properties. On initial approach ...
    • Elongational Viscosity of Monodisperse and Bidisperse Polystyrene Melts 

      Nielsen, Jens K.; Rasmussen, Henrik K.; Hassager, Ole; McKinley, Gareth H. (2007-01-23)
      The startup and steady uniaxial elongational viscosity have been measured for two monodisperse polystyrene melts with molecular weights of 52 kg/mole and 103 kg/mole, and for three bidisperse polystyrene melts. The ...
    • Experimental Investigations of Elastic Tail Propulsion At Low Reynolds Number 

      Yu, Tony S.; Lauga, Eric; Hosoi, A.E. (2007-05-04)
      A simple way to generate propulsion at low Reynolds number is to periodically oscillate a passive flexible filament. Here we present a macroscopic experimental investigation of such a propulsive mechanism. A robotic swimmer ...
    • The Flexure-based Microgap Rheometer (FMR) 

      Clasen, Christian; Gearing, Brian P.; McKinley, Gareth H. (2007-01-23)
      We describe the design and construction of a new microrheometer designed to facilitate the viscometric study of complex fluids with very small sample volumes (1-10 μl)and gaps of micrometer dimensions. The Flexure-based ...
    • How Dilute are Dilute Solutions in Extensional Flows? 

      Clasen, Christian; Plog, J.P.; Kulicke, W.-M.; Owens, M.; Macosko, C.; e.a. (2007-01-23)
      We investigate the concentration-dependence of the characteristic relaxation time of dilute polymer solutions in transient uniaxial elongational flow. A series of monodisperse polystyrene solutions of five different ...
    • Inductively Heated Shape Memory Polymer for the Magnetic Actuation of Medical Devices 

      Buckley, Patrick R.; McKinley, Gareth H.; Wilson, Thomas S.; Small IV, Ward; Benett, William J.; e.a. (2007-01-23)
      Presently there is interest in making medical devices such as expandable stents and intravascular microactuators from shape memory polymer (SMP). One of the key challenges in realizing SMP medical devices is the implementation ...
    • Linear to Non-linear Rheology of Wheat Flour Dough 

      Ng, Trevor S.K.; McKinley, Gareth H.; Padmanabhan, Mahesh (2007-01-23)
      We provide an overview of transient extensional rheometry techniques for wheat flour doughs in which the deformation and material response is well defined. The behavior of a range of model doughs was explored with a ...
    • Preferential Association of Segment Blocks in Polyurethane Nanocomposites 

      James-Korley, LaShanda T.; Liff, Shawna M.; Kumar, Nitin; McKinley, Gareth H.; Hammond, Paula T. (2007-01-23)
      Controlling the level of dispersion of silicate layers in polymer matrices through intermolecular interactions and exploiting these interactions to enhance thermomechanical behavior are key challenges in the field of polymer ...
    • Tuning Gastropod Locomotion: Modeling The Influence Of Mucus Rheology on the Cost of Crawling 

      Lauga, Eric; Hosoi, A.E. (2007-05-04)
      Common gastropods such as snails crawl on a solid substrate by propagating muscular waves of shear stress on a viscoelastic mucus. Producing the mucus accounts for the largest component in the gastropod’s energy budget, ...