Synthetische Kunststoffe

Geier, Simon; Schmitz, Harald; Göschel, U.; Eyerer, Peter; Ostrowicki, Andreas; Woicke, Nina; Ulrich, Christian; Lutz, Wolfgang; Eschl, Johannes; Rüb, Guntmar; Keuerleber, Martin; Diemert, Jan; Hauk, Jürgen; Stieneker, Axel; Woidasky, Jörg; Fischer, Ingo; Kretschmer, Karsten; Ober, Ludwig; Kohlert, Christian; Ganslmeier, Stefan; Schlade, Christian; Schüle, Helmut; Kurz, Klaus; Tönnes, Kai Uwe; Elsner, Peter; Protte, Rainer; Liebing, David; Rodriguez, Ana K.; Raisch, Sven Robert; Dern, Heinz-Jürgen; Schlünken, Sigrid; Bräuning, Rüdiger; König, Alexander

doi:10.1007/978-3-642-16173-5_2

Cited by 3 publications

(13 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The peak temperatures of the major melting events in the DSC curves of the rPE materials are all between 131 °C and 132 °C, whereas those of the minor melting peaks ranged from 159 °C to 162 °C. The former is in good agreement with typical melting peak temperatures of PE-HD [ 20 ], while the latter is attributed to the melting of a PP fraction [ 16 , 20 ]. For the rPP materials, the peak temperatures of the major melting peaks were in the range of 159 °C to 164 °C, whereas the minor melting events have peak temperatures between 124 °C and 127 °C.…”

Section: Resultssupporting

confidence: 76%

“…For the rPP materials, the peak temperatures of the major melting peaks were in the range of 159 °C to 164 °C, whereas the minor melting events have peak temperatures between 124 °C and 127 °C. In this case, the former corresponds well with PP [ 16 , 20 ], while the latter fits to both PE-HD and PE-LLD. Due to the fact that PE-LLD is mainly used in film applications [ 19 ], it can be assumed that the present PE phase is likely PE-HD, and the comparatively moderate melting peak temperatures are a consequence of the low volume fraction and the mixing with PP as reported in the literature [ 57 ].…”

Section: Resultsmentioning

confidence: 58%

“…There is little variation between suppliers and grades. Furthermore, these numbers are within the range typically expected for unfilled high-density polyethylene (PE-HD) resins [ 19 , 20 ]. The density values of the rPP materials varied between 0.904 g/cm 3 (rPP-D) and 0.924 g/cm 3 (rPP-F).…”

Section: Resultsmentioning

confidence: 66%

“…The average density over all rPPs is 0.916 g/cm 3 . With the exception of rPP-D, these numbers are situated rather at the top end of the density value range typically expected for unfilled PP resins [ 16 , 20 ]. The spread between lowest and highest density is slightly higher in the rPP group than in the rPE group.…”

Section: Resultsmentioning

confidence: 97%

“…This highlights that both inorganics content and polyolefin cross-contamination, even at seemingly low nominal levels of a few percent by mass, significantly affect overall recyclate density. This finding might be of particular interest for rPE materials, because besides the MFR, the density is one of the prime characteristics to differentiate PE grades in industrial practice [ 19 , 20 ] and relevant standardization [ 64 ].…”

Section: Resultsmentioning

confidence: 99%

See 4 more Smart Citations

Characterization of Composition and Structure–Property Relationships of Commercial Post-Consumer Polyethylene and Polypropylene Recyclates

et al. 2021

View full text Add to dashboard Cite

The current efforts in moving closer towards a circular plastics economy puts massive pressure on recycled plastics, especially recycled polyethylene (rPE) and recycled polypropylene (rPP) to enter new markets. Their market penetration remained low so far, despite PE and PP constituting the largest share of plastic wastes. However, with the current imperative of more circularity comes a new focus on performance of recyclates. Hence, a detailed understanding of composition and structure–property relationships of post-consumer recyclates has to be developed. Five recycling companies from the Austrian and German markets were asked to supply their purest high-quality rPE and rPP grades. These were characterized by differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), and Fourier-transform infrared (FTIR) spectroscopy, and micro-imaging. Technological characterization included density measurements, determination of the melt flow rate (MFR), and Charpy impact testing. All recyclates contained diverse contaminants and inclusions ranging from legacy fillers like calcium carbonate to polymeric contaminants like polyamides or polyolefin cross-contamination. The overall amount, size, and distribution of contaminants varied significantly among suppliers. Furthermore, first structure–property relationships for polyolefin recyclates that link inorganic content and polymeric purity with density and impact performance could be derived.

show abstract

Section: Resultssupporting

confidence: 76%