Influence of Process Conditions on the Local Shrinkage and on the Pressure Evolution inside the Mold Cavity of the Injection Molded Polypropylene in Two Modifications - PP Homopolymer; 40 % Talc Filled PP

Abstract:

This work is focusing on optimization of the chosen process conditions (melt temperature, injection rate and holding pressure) and their mutual interaction on the local shrinkage of wall thickness carried out on rectangular plate. The test was applied on semicrystalline polymer in following modifications - polypropylene homopolymer and 40 % talc filled polypropylene. For better understanding of processes influencing shrinkage the pressure evolution inside cavity was captured by transducers placed near the gate and at the end of flow.

• Periodical: Key Engineering Materials (Volume 669)
• Pages: 11-18
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.669.11
• Online since: October 2015
• Authors: Robert Záboj
• Keywords: Cavity Pressure, Injection Molding, Polypropylene, Shrinkage

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DOI: 10.1115/msec2007-31082