Surface interactions in a shear field

Authors

  • Laura J. Dietsche,

    1. Dept. of Chemical Engineering, University of California at Berkeley, and Center for Advanced Materials, Lawrence Berkeley Laboratory, Berkeley, CA 94720
    Current affiliation:
    1. Dow Chemical, Midland, MI 48674
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  • Morton M. Denn,

    Corresponding author
    1. Dept. of Chemical Engineering, University of California at Berkeley, and Center for Advanced Materials, Lawrence Berkeley Laboratory, Berkeley, CA 94720
    • Dept. of Chemical Engineering, University of California at Berkeley, and Center for Advanced Materials, Lawrence Berkeley Laboratory, Berkeley, CA 94720
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  • Alexis T. Bell

    1. Dept. of Chemical Engineering, University of California at Berkeley, and Center for Advanced Materials, Lawrence Berkeley Laboratory, Berkeley, CA 94720
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Abstract

The dynamics of chain exchange between flowing bulk melt and the channel wall were studied for oligomeric polyolefins using attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FTIR). The dynamics are dominated by a surprisingly slow first-order process which depends on flow rate and materials of construction of the channel wall. The picture which seems to emerge is an entropically-driven flow-rate- (or stress-) dependent adsorption equilibrium which retards the exchange between the surface and bulk.

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