PET foaming: development of a new class of rheological additives for improved processability

PET foaming: development of a new class of rheological additives for improved processability

Clizia Aversa, Massimiliano Barletta, Annalisa Genovesi, Annamaria Gisario

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Abstract. Polymer foaming is a process broadly used for manufacturing light weight packaging solutions. Polystyrene (PS) is the most widespread material for this application, as it combines easy processability, low cost and high performance of the resulting items. However, foamed PS is difficult to recycle and highly polluting for the oceans and aquatic environment. Polyethylene terephthalate (PET) is, instead, commonly recycled and R-PET is broadly used for several industrial applications. Yet, PET quickly loses viscosity during the foaming process, due to thermo-hydrolytic and oxidative degradation thus causing poor foaming. In this paper, an innovative combination of chain extenders, anti-oxidants and nucleating agents to modify PET rheology is studied. The additives were experimented both in off-line and in-line apparatus. The experimental results show PET rheology can be customized by appropriately modulating the content of the different additives, thus making PET suitable for foaming process of high-quality items.

Polymers, Extrusion, Foaming

Published online 9/5/2023, 9 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Clizia Aversa, Massimiliano Barletta, Annalisa Genovesi, Annamaria Gisario, PET foaming: development of a new class of rheological additives for improved processability, Materials Research Proceedings, Vol. 35, pp 376-384, 2023


The article was published as article 45 of the book Italian Manufacturing Association Conference

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