Analyzing the Sharkskin Instability
نویسندگان
چکیده
The stretching and recoiling of polymer chains leads to the characteristic ridge pattern as a soft material exits narrow nozzle.
منابع مشابه
Control of the sharkskin instability in the extrusion of polymer melts using induced temperature gradients
Flow instabilities occur in a variety of commercial polymer processing operations including extrusion, film blowing, fiber spinning and coating. During the extrusion of molten polymer through capillary or slit die geometries, a transition from a smooth surface to a nearly periodic ridge-like surface distortion has been observed at a critical shear rate or wall shear stress (Petrie and Denn 1976...
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The sharkskin surface instability is commonly observed in the extrusion of polymer melts. We present a series of experiments in which a specifically designed rectangular slit die with insulated and independently heated sides and is used to induce precise temperature gradients across a flowing polyethylene melt. Our previous experiments demonstrated that the character of the surface distortions ...
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ژورنال
عنوان ژورنال: Physics
سال: 2021
ISSN: ['2624-8174']
DOI: https://doi.org/10.1103/physics.14.s106