Mechanical short-term and long-term properties of PP recyclate blends

The amount of recycled material in new products should be increased in the next few years. By adding virgin material, the mechanical properties of the pure recyclate can be improved. In this work, 10 % and 40 % post-consumer recyclate was added to a virgin material and analyzed. Both raw materials were also tested. The short-term as well as the long-term properties decrease with increasing recyclate content. The recyclate has a higher influence on the young’s modulus, yield stress and slow crack growth resistance than on the notched impact toughness.

Recycling of polymers recently gained increasing attention among the scientific, industrial, andcommercial community as well as the wider public. On one hand it is due to the materials’ economicand technical relevance and on the other hand the environmental and social challengesassociated with waste perspective of plastic products (Aumnate, Rudolph, & Sarmadi, 2019;Rajendran, et al., 2013; Reichel, Schienmakere, & Gillabel, 2016). Aside from polyethylene (PE) with a market share of 19.4%, polypropylene (PP) is the most commonpolymer. Most PP products are used in packaging (~40 %) followed by building & construction(~20 %) and automotive (~10 %). In the building and construction sector the operationallifetime is more than 50 years, therefore the long structural lifetimes are required. In Europe,almost 30 Mio. t of post-consumer waste was collected, after sorting 32 % of the post-consumerwaste is sent to recycler. Only 13 % of the collected waste is used in new products, the highestamount of 46 % is the building & construction sector (PlasticsEurope AISBL, 2019). Most recyclatesare therefore used in products that require a long structural lifetime. By adding virgin material,the mechanical properties of the recyclate can be improved and a higher amount of recyclates can be processed into new products (Utracki & Wilkie, 2014).

Copyright: © Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben
Quelle: Recy & Depotech 2022 (November 2022)
Seiten: 2
Preis inkl. MwSt.: € 1,00
Autor: J. Hinczica
Jutta Geier
Ulrike Kirschnick
Dipl.-Ing. Alexandra Holzer
C. Holzer

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