A melt flow index-based approach for the viscosity curves determination

Keltoum OUBELLAOUCH; R. PELACCIA; Paolo POZZI; Giulia ZANIBONI; L. Orazi; L. DONATI; B. REGGIANI

doi:10.21741/9781644903131-298

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A melt flow index-based approach for the viscosity curves determination

OUBELLAOUCH Keltoum, PELACCIA Riccardo, POZZI Paolo, ZANIBONI Giulia, ORAZI Leonardo, DONATI Lorenzo, REGGIANI Barbara

Abstract. To optimize the polymers processing technologies, a rheological characterization of the polymer is essential to predict its behavior at specific temperatures and under varying shear rates. Simulating this process requires providing the simulation software with viscosity curves for the polymer to be processed, ensuring a reliable simulation. However, traditional rheological characterization utilizing a capillary rheometer is known for its high cost, time-intensive nature, and the need for skilled operators. In this study, a more cost-effective approach is proposed, using the Melt Flow Indexer (MFI) to obtain the experimental viscosity curves. These undergo an innovative numerical procedure based on simulating the MFI tests, reducing the numerical-experimental error in terms of pressure applied to the molten polymer. This methodology is applied to characterize three different thermoplastic polymers: polypropylene, 30% glass-reinforced polypropylene and 30% glass-reinforced polyamide. The viscosity curves obtained through this methodology are then compared to those obtained using the capillary rheometer, serving as a reference to assess the accuracy of the proposed approach.

Keywords
Melt Flow Index, Capillary Rheometer, Viscosity Curves, Optimization

Published online 4/24/2024, 10 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: OUBELLAOUCH Keltoum, PELACCIA Riccardo, POZZI Paolo, ZANIBONI Giulia, ORAZI Leonardo, DONATI Lorenzo, REGGIANI Barbara, A melt flow index-based approach for the viscosity curves determination, Materials Research Proceedings, Vol. 41, pp 2720-2729, 2024

DOI: https://doi.org/10.21741/9781644903131-298

The article was published as article 298 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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