Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene
Post-consumer recyclates often have a property profile that results from mixing a variety of products, which are made from different materials, produced by different processing methods, and coming from applications with different lifetimes. This usually leads to a mixture of all these material prope...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-03-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/15/7/1717 |
| _version_ | 1797607143715635200 |
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| author | Ines Traxler Hannes Kaineder Joerg Fischer |
| author_facet | Ines Traxler Hannes Kaineder Joerg Fischer |
| author_sort | Ines Traxler |
| collection | DOAJ |
| description | Post-consumer recyclates often have a property profile that results from mixing a variety of products, which are made from different materials, produced by different processing methods, and coming from applications with different lifetimes. This usually leads to a mixture of all these material properties in the recycling process. In contrast, virgin materials are specifically designed for applications and thus offer all the necessary properties for the intended products. In order to be able to use recycled materials for specific and demanding applications, not only the viscosity, which is important for processing and often varies greatly with recyclates, but also the mechanical properties, particularly the tensile modulus and impact strength, must be adjusted. For this purpose, various virgin materials of polypropylene homopolymers, random copolymers, and block copolymers with different flowabilities were mixed in different proportions and their properties were determined. The flowability of homopolymers and random copolymers in the blend behaved very similarly, while block copolymers exhibited a different behavior in some cases. By incorporating homopolymers into blends, the stiffness of the resulting material blend can be very well adjusted. The addition of random copolymers can increase strain at break, and the addition of block copolymers results in a significant increase in impact strength. In numbers, the maximum adjustment range for tensile modulus, yield stress, strain at break, and impact strength are 880 MPa, 14 MPa, 185%, and 6.9 kJ/m<sup>2</sup>, respectively. While a good and reliable prediction of property profile is possible for polymer blends with different virgin materials, the resulting material properties for polymer blends of virgin and recycled materials are also influenced by impurities. In this work, however, a good prediction was also achieved for recyclate blends. |
| first_indexed | 2024-03-11T05:27:03Z |
| format | Article |
| id | doaj.art-b2385e1ccf244cca9cd7465933a4898e |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-11T05:27:03Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-b2385e1ccf244cca9cd7465933a4898e2023-11-17T17:26:32ZengMDPI AGPolymers2073-43602023-03-01157171710.3390/polym15071717Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer PolypropyleneInes Traxler0Hannes Kaineder1Joerg Fischer2Competence Center CHASE GmbH, Altenberger Strasse 69, 4040 Linz, AustriaInstitute of Polymeric Materials and Testing, Johannes Kepler University, Altenberger Strasse 69, 4040 Linz, AustriaInstitute of Polymeric Materials and Testing, Johannes Kepler University, Altenberger Strasse 69, 4040 Linz, AustriaPost-consumer recyclates often have a property profile that results from mixing a variety of products, which are made from different materials, produced by different processing methods, and coming from applications with different lifetimes. This usually leads to a mixture of all these material properties in the recycling process. In contrast, virgin materials are specifically designed for applications and thus offer all the necessary properties for the intended products. In order to be able to use recycled materials for specific and demanding applications, not only the viscosity, which is important for processing and often varies greatly with recyclates, but also the mechanical properties, particularly the tensile modulus and impact strength, must be adjusted. For this purpose, various virgin materials of polypropylene homopolymers, random copolymers, and block copolymers with different flowabilities were mixed in different proportions and their properties were determined. The flowability of homopolymers and random copolymers in the blend behaved very similarly, while block copolymers exhibited a different behavior in some cases. By incorporating homopolymers into blends, the stiffness of the resulting material blend can be very well adjusted. The addition of random copolymers can increase strain at break, and the addition of block copolymers results in a significant increase in impact strength. In numbers, the maximum adjustment range for tensile modulus, yield stress, strain at break, and impact strength are 880 MPa, 14 MPa, 185%, and 6.9 kJ/m<sup>2</sup>, respectively. While a good and reliable prediction of property profile is possible for polymer blends with different virgin materials, the resulting material properties for polymer blends of virgin and recycled materials are also influenced by impurities. In this work, however, a good prediction was also achieved for recyclate blends.https://www.mdpi.com/2073-4360/15/7/1717polypropylene recyclatemixing rulespolymer blendsMFRmechanical propertiesdesign from recycling |
| spellingShingle | Ines Traxler Hannes Kaineder Joerg Fischer Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene Polymers polypropylene recyclate mixing rules polymer blends MFR mechanical properties design from recycling |
| title | Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene |
| title_full | Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene |
| title_fullStr | Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene |
| title_full_unstemmed | Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene |
| title_short | Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene |
| title_sort | simultaneous modification of properties relevant to the processing and application of virgin and post consumer polypropylene |
| topic | polypropylene recyclate mixing rules polymer blends MFR mechanical properties design from recycling |
| url | https://www.mdpi.com/2073-4360/15/7/1717 |
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