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Molecular Dynamics Simulations of Polymer/Post Collisions. AIChE@2003.SF. Gary W. Slater & Martin Kenward Universit é d’ Ottawa (physique). Exploiting a Transient Elongational Flow Field to Prepare Monodisperse Polymers by Midpoint Chain Scission.
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Molecular Dynamics Simulations of Polymer/Post Collisions AIChE@2003.SF Gary W. Slater & Martin Kenward Université d’Ottawa (physique) G. W. Slater
Exploiting a Transient Elongational Flow Field to Prepare Monodisperse Polymers by Midpoint Chain Scission • Brett A. Buchholz1, Jacob M. Zahn1,‡, Martin Kenward2, • Gary W. Slater2, Annelise E. Barron1 • 1Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA • 2Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada • ‡Present Address: Department of Chemical Engineering, Stanford University, Palo Alto, CA, USA G. W. Slater
Effluent collection Fused-silica capillary Nitrogen gas port Pressurized chamber Tightening screw Polymer solution Pressure-loading device G. W. Slater
Capillary inner diameter = 250 m, outer diameter = 359 m The elongational flow field • Converging stream lines and their likely effect on polymer conformation • Polymer chains uncoil and stretch, and in some cases can become fully elongated • Three critical times: passage time; elongation time; scission time. G. W. Slater
Modeling results: LPA • Good fit to experimental data obtained • There is the clear possibility of more than one breakage event per pass • Distribution of scission around center point (0)only 10% • m0 fluctuated for each pass • Simulation of the result of 50 passes through the system (Mw = 546 kDa; PDI = 1.077) G. W. Slater
Nanofluidics: New Physics, New Devices, New Frontiers AIChE@2003.SF Gary W. SLATER Université d’Ottawa (physique) Ottawa, Canada G. W. Slater
Nano-sims G. W. Slater
Nano-fluctuations Fluid density temperature G. W. Slater