{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:17:43Z","timestamp":1785428263859,"version":"3.56.0"},"reference-count":34,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T00:00:00Z","timestamp":1784851200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100018987","name":"Technical University of Cluj-Napoca","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100018987","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/03r8nwp71","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Problem statement: Contaminated mixed plastic waste\u2014bearing metallic, paper, cardboard and organic residues\u2014remains largely excluded from mechanical recycling because conventional routes require a costly, water- and energy-intensive washing\u2013drying pretreatment. Research gap: No published study combines a fully dry, washing-free valorisation route for such waste with certified mechanical characterisation and a quantified CO2 mass balance that explicitly credits elimination of the washing\u2013drying stage. Methodology: This study presents DMP (Downcycled Mixed Plastic), a patented (OSIM, Romania) dry valorisation process based on continuous single-screw extrusion (D = 150 mm, L\/D = 17.3), characterised through differential scanning calorimetry (DSC), certified mechanical\/thermal testing at accredited Romanian laboratories, Weber-number dispersion analysis, and a process-parameter sensitivity study. Key findings: The composite exhibits certified mechanical properties (tensile strength 9.22 MPa, elongation at break 112.8%, compressive strength 14.5 MPa); composition\u2013property analysis across four batches shows that increasing the PP weight fraction from 20 to 28 wt% raises tensile strength by 8.3% while reducing elongation by 5.2%; a computed Weber number (We = 166.7 \u226b We_crit) is consistent with fine PP-phase dispersion within the PE matrix; the sensitivity study confirms statistically robust structure\u2013property relationships (R2 = 0.93\u20130.98); and the CO2 mass balance establishes a net avoidance of 3.150 t CO2 eq per tonne of waste processed relative to conventional wet recycling. Significance: dry, washing-free processing is a technically promising pathway for valorising plastic waste streams currently considered non-recyclable, potentially reducing production cost by 60\u201370% relative to wet recycling, pending additional characterisation identified as priorities for future work.<\/jats:p>","DOI":"10.3390\/polym18151815","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T01:26:23Z","timestamp":1785115583000},"page":"1815","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Characterisation of Eco-Innovative Polymer Composites Obtained by Processing Hard-to-Recycle Plastic Waste: Extrusion Parameters, Chemical Composition, and Mechanical Performance"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2116-5026","authenticated-orcid":false,"given":"Tudor Andrei","family":"Rusu","sequence":"first","affiliation":[{"name":"Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rusu","family":"Tiberiu","sequence":"additional","affiliation":[{"name":"Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, Str. Memorandumului 28, 400114 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,24]]},"reference":[{"key":"ref_1","unstructured":"European Parliament, and Council of the European Union (2006). Directive 2006\/12\/EC of the European Parliament and of the Council of 5 April 2006 on Waste. Off. J. Eur. Union, L114, 9\u201321."},{"key":"ref_2","unstructured":"European Commission (2014). Towards a Circular Economy: A Zero Waste Programme for Europe, European Commission. 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