| Autor: |
Traxler, Ines, Fischer, Joerg, Felgel-Farnholz, Alexander, Laske, Stephan |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings; 2024, Vol. 3158 Issue 1, p1-6, 6p |
| Abstrakt: |
Thermoforming of polypropylene (PP) requires low flowability and high stiffness, which are relevant to the processing and the application, respectively. A selection of four commercially available post-consumer PP recyclates was tested regarding their quality. Therefore, infrared (IR) spectroscopy, thermoanalytical measurements and tensile tests were performed on material level. Furthermore, multilayer cups with top layers of virgin material and core layers of the respective recyclates were produced and product tests for the shrinkage diameter, the top load as well as the migration were performed. IR measurements revealed different amounts of polyethylene contaminations in all recyclates which was confirmed by crystallization enthalpies of the thermoanalytical measurements. A correlation of the results of both characterization methods was established. Mechanical tests revealed inferior stiffness of the recyclates compared to the reference material. The inferior properties confirm the use of multilayer structures for the cups to keep the properties in the target ranges. To combine the results of material and product tests two correlations were deduced. While the correlation of crystallization enthalpy and shrinkage diameter does not reveal a good comparison, a non-linear correlation of tensile modulus and top load was found. A minor change to lower tensile moduli leads to a major change to inferior product properties represented by a low top load. Migration tests revealed significant differences between all recyclates. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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