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A Dielectric Slit Die for In-Line Monitoring of Polymer Compounding



Anthony J. Bur, S C. Roth, M M. McBrearty


The dielectric slit die is an instrument that is designed to measure electrical, rheological, ultrasonics, optical and other properties of a flowing liquid. In one application it is connected to the exit of an extrudder, pump or mixing machine that passes liquefied material such as molten plastics, solvents, slurries, colloidal suspensions and foodstuffs into the sensing region of slit shaped die. Dielectric sensing is the primary element of the slit die, but in addition to the dielctric sensor, the die contains other sensing devices such as pressure, optical and ultrasonics sensors.The slit die has a flexible design that permits interchangability among sensors and sensor positions. To demonstrate sensor operation, we present data from extrusion and compounding of a polymer/clay nanocomposite.
Review of Scientific Instruments
No. 4


dielectric properties, microstructure, nanocomposites, nylon 12, optical sensor, polyamide, process monitoring


Bur, A. , Roth, S. and McBrearty, M. (2004), A Dielectric Slit Die for In-Line Monitoring of Polymer Compounding, Review of Scientific Instruments, [online], (Accessed July 18, 2024)


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Created April 1, 2004, Updated February 19, 2017