Investigation of the effects of gas-counter-pressure injection molding on the properties and manufacturability of post-consumer recycled polypropylene

Investigation of the effects of gas-counter-pressure injection molding on the properties and manufacturability of post-consumer recycled polypropylene


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Abstract. In contemporary times, the most effective strategy for mitigating the environmental effects of plastics and their manufacturing is recycling. However, producing high-quality items from recycled materials remains a challenge. This study addresses these challenges, specifically focusing on the injection molding process for recycled polypropylene. Key issues identified include poor surface finish of the molded items, mold contamination with oily residues, and strong odors during processing. The proposed solution involves the innovative use of gas counter pressure in conjunction with injection molding. The study explores various nitrogen pressure levels to assess their impact. Findings indicate that an optimal pressure level significantly improves the surface quality of the products and reduces the accumulation of dirt in the mold cavities. While gas counter pressure does not mitigate odor emissions, it represents a promising step forward in developing a high-quality recycled polypropylene compound. This approach could pave the way for more advanced recycling techniques, enhancing the quality of products made from recycled plastics.

Gas Counter Pressure, Injection Molding, Recycling, Post-Consumer Polypropylene

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: BORTOLETTO Anna, BOVO Enrico, SORGATO Marco, LUCCHETTA Giovanni, Investigation of the effects of gas-counter-pressure injection molding on the properties and manufacturability of post-consumer recycled polypropylene, Materials Research Proceedings, Vol. 41, pp 2730-2739, 2024


The article was published as article 299 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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