Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material
Due to the lack of raw material and forced by political demand, an increasing percentage of postconsumer materials (PCR) shall be used in all processing methods in polymer technology. Thermoforming, as one of the oldest polymer-processing methods, has special requirements regarding the melt stabilit...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-08-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/14/15/3172 |
| _version_ | 1797432678676430848 |
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| author | Lisa-Maria Wittmann Joachim Kaschta Dietmar Drummer |
| author_facet | Lisa-Maria Wittmann Joachim Kaschta Dietmar Drummer |
| author_sort | Lisa-Maria Wittmann |
| collection | DOAJ |
| description | Due to the lack of raw material and forced by political demand, an increasing percentage of postconsumer materials (PCR) shall be used in all processing methods in polymer technology. Thermoforming, as one of the oldest polymer-processing methods, has special requirements regarding the melt stability at high temperatures. Low melt stability affects the thermoforming in a negative manner, as the low stiffness leads the sheet to sag during the heating phase. In this study, two-layer sheets are used in order to improve melt stability of PCR material. The focus is placed on the influence of rheological properties on the biaxial stretching behavior of mono- and two-layer sheets in partially molted state. In order to create a stabilizing layer, two different thermoformable virgin materials with a melt flow rate (MFR) of 3 g/10 min and 6 g/10 min were chosen. The second layer consists of instable PCR materials with a MFR of 16 g/10min and 50 g/10 min. Rheological investigations, molecular characterization and biaxial stretching tests are used to show the benefit of two-layer sheets for processing PCR material under elongational stress. The results show that the use of two-layer sheets can improve the biaxial stretching properties, so that two-layer sheets can offer a significant potential in the processing of PCR materials in thermoforming. |
| first_indexed | 2024-03-09T10:05:06Z |
| format | Article |
| id | doaj.art-0cb4dd7e286742b3b7d8e19900756fc4 |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-09T10:05:06Z |
| publishDate | 2022-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-0cb4dd7e286742b3b7d8e19900756fc42023-12-01T23:07:27ZengMDPI AGPolymers2073-43602022-08-011415317210.3390/polym14153172Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer MaterialLisa-Maria Wittmann0Joachim Kaschta1Dietmar Drummer2Department of Mechanical Engineering, Institute of Polymer Technology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Am Weichselgarten 10, 91058 Erlangen, GermanyDepartment of Material Science and Engineering, Institute of Polymer Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Martenstraße 7, 91058 Erlangen, GermanyDepartment of Mechanical Engineering, Institute of Polymer Technology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Am Weichselgarten 10, 91058 Erlangen, GermanyDue to the lack of raw material and forced by political demand, an increasing percentage of postconsumer materials (PCR) shall be used in all processing methods in polymer technology. Thermoforming, as one of the oldest polymer-processing methods, has special requirements regarding the melt stability at high temperatures. Low melt stability affects the thermoforming in a negative manner, as the low stiffness leads the sheet to sag during the heating phase. In this study, two-layer sheets are used in order to improve melt stability of PCR material. The focus is placed on the influence of rheological properties on the biaxial stretching behavior of mono- and two-layer sheets in partially molted state. In order to create a stabilizing layer, two different thermoformable virgin materials with a melt flow rate (MFR) of 3 g/10 min and 6 g/10 min were chosen. The second layer consists of instable PCR materials with a MFR of 16 g/10min and 50 g/10 min. Rheological investigations, molecular characterization and biaxial stretching tests are used to show the benefit of two-layer sheets for processing PCR material under elongational stress. The results show that the use of two-layer sheets can improve the biaxial stretching properties, so that two-layer sheets can offer a significant potential in the processing of PCR materials in thermoforming.https://www.mdpi.com/2073-4360/14/15/3172two-layer sheetbiaxial stretchingpostconsumer material |
| spellingShingle | Lisa-Maria Wittmann Joachim Kaschta Dietmar Drummer Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material Polymers two-layer sheet biaxial stretching postconsumer material |
| title | Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material |
| title_full | Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material |
| title_fullStr | Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material |
| title_full_unstemmed | Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material |
| title_short | Biaxial Elongation Behavior in Partially Molted State of Two-Layer Sheets Containing Postconsumer Material |
| title_sort | biaxial elongation behavior in partially molted state of two layer sheets containing postconsumer material |
| topic | two-layer sheet biaxial stretching postconsumer material |
| url | https://www.mdpi.com/2073-4360/14/15/3172 |
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