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Measuring melt density in polymer extrusion processes using shear ultrasound waves

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Abstract

Ultrasound shear waves propagating at a frequency of 2.25 MHz are used to measure the density of polymer melt in real time during extrusion process. The acoustic impedance of the polymer melt is calculated using the measured reflection coefficient off the polymer melt interface boundary. A normalisation procedure was developed to normalise for the effect of other process and material parameters not pertinent to the melt density. The ultrasound measurement is independent of the attenuation in the polymer melt and the thickness of the melt stream, which makes this technique highly desirable for heavily loaded polymers and large extrusion dies.

The system was evaluated using polyvinyl chloride compounds containing various levels of foaming agent and process aid at fixed processing conditions. The system measurements of the melt density are compared to the weight of the extrudate measured by a laboratory scale. The correlation coefficient between the two measurements is approximately 96%.

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References

  1. Erwin L, Dohner J (1984) Measurement of mixing in polymer melts by focused ultrasound. Polym Eng Sci 24(16):1277

    Article  Google Scholar 

  2. Piche L (1984) Ultrasonic velocity measurement for the determination of density in polyethylene. Polym Eng Sci 24(17):1354

    Article  Google Scholar 

  3. Gendron R, Tatibouet J, Guevremont J, Dumoulin M, Piche L (1995) Ultrasonic behavior of polymer blends. Polym Eng Sci 35(1):79

    Article  Google Scholar 

  4. Sahnoune A, Hamel A, Piche L (1998) Ultrasonic characterization and rheology of polymer foams. In: Proceedings of SPE ANTEC, Atlanta, April 1998, 56(2):1927

  5. Gendron R, Piche L, Hamel A, Doumoulin M, Tatibouet J (1997) Ultrasonic characterization of extrusion instabilities. In: Proceedings of SPE ANTEC Toronto, April 1997, 55(2):2254

  6. Bear RS, Brown SD (1993) Ultrasonic pulse method with nonlinear calibration for quantitative monitoring of polymer blends. Anal Chem 65:1169

    Article  Google Scholar 

  7. Verdier C, Piau M (1996) Analysis of the morphology of polymer blends using ultrasound. J Phys D Appl Phys 29:1455

    Article  Google Scholar 

  8. Piche L (1998) Ultrasonic probe for on-line process monitoring. In: Proceedings of SPE ANTEC Atlanta, April 1998, 56(3):3617

  9. Jen CK, Chen J-Y, Hoa SV, Nguyen KT, Legoux J-G, Hébert H 1997) Clad buffer rods for in-situ process monitoring. In: Proceedings of the IEEE symposium on ultrasound, Toronto, October 1997, 1:801

  10. Brown EC, Collins TLD, Dawson AJ, Olley P, Coates PD (1998) Ultrasound: a virtual instrument approach for monitoring of polymer melt variables. In: Proceedings of SPE ANTEC, Atlanta, April 1998, 1:335

  11. França DR, Wen S-SL, Jen C-K, Nguyen KT, Hébert H (1997) Advances in on-line monitoring of polymer injection molding process. In: Proceedings of the IEEE symposium on ultrasound, Toronto, October 1997, pp 807

  12. Wang H, Cao B, Jen CK, Nguyen KT, Viens M (1997) On-line ultrasonic monitoring of the injection molding process. Polym Eng Sci 37(2):363

    Article  Google Scholar 

  13. Gendron R, Daigneault L, Tatibouet J, Doumoulin M (1994) Residence time distribution in extruders determined by in-line ultrasonic measurements. In: Proceedings of SPE ANTEC, San Francisco, May 1994, 52:167

  14. Sahnoune A, Piche L, Hamel A, Gendron R, Daigneault L (1997) Ultrasonic monitoring of foaming in polymers. In: Proceedings of SPE ANTEC Toronto, April 1997, 55(2):2259

  15. Sahnoune A, Hamel A, Piche L (1998) Ultrasonic characterization and rheology of polymer foams. In: Proceedings of SPE ANTEC Atlanta, April 1998, 2:1927

  16. Gendron R, Daigneault LE, Tatibouet J, Doumoulin MM (1996) Residence time distribution in extruders determined by in-line ultrasonic measurements. Adv Polym Technol 15(2):111

    Article  Google Scholar 

  17. Sahnoune A, Piche L (1996) Glass transition and ultrasonic relaxation in polystyrene. In: Proceedings of the 1996 MRS fall meeting, Boston, December 1996

  18. Shah VV (1996) Effect of viscosity on ultrasound wave reflection from a solid/liquid interface. Ultrasonics 34(8):817

    Article  Google Scholar 

  19. Mason WP, McSkimin HJ (1952) Dynamic shear properties of polymers at ultrasonic frequencies. J Bell Sys Tech 31:122

    Article  Google Scholar 

  20. Sheen SH, Chien H-T, Rapits AC (1995) An in-line ultrasonic viscometer. Rev Prog Quantit Nondestruct Eval 14A:1151

    Google Scholar 

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Authors and Affiliations

  1. Industrial and Manufacturing Engineering Department, University of Wisconsin-Milwaukee, 3200 N. Cramer St., Milwaukee, WI, 53201, USA

    Nidal H. Abu-Zahra

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  1. Nidal H. Abu-Zahra
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Correspondence to Nidal H. Abu-Zahra.

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Abu-Zahra, N. Measuring melt density in polymer extrusion processes using shear ultrasound waves. Int J Adv Manuf Technol 24, 661–666 (2004). https://doi.org/10.1007/s00170-003-1743-6

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  • DOI: https://doi.org/10.1007/s00170-003-1743-6

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