{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T04:36:17Z","timestamp":1791606977424,"version":"4.3.4"},"reference-count":59,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,18]],"date-time":"2024-09-18T00:00:00Z","timestamp":1726617600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000923","name":"Australian Research Council","doi-asserted-by":"publisher","award":["IH200100010"],"award-info":[{"award-number":["IH200100010"]}],"id":[{"id":"10.13039\/501100000923","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Paintback Limited","award":["IH200100010"],"award-info":[{"award-number":["IH200100010"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The need for ending plastic waste and creating a circular economy has prompted significant interest in developing a new family of composite materials through recycling and recovery of waste resources (including bio-sourced materials). In this work, a family of natural fiber-reinforced plastic composites has been developed from paint pail waste recycled polypropylene (rPP) and waste wool fibers of different diameter and aspect ratio. Composites were fabricated by melt processing using polypropylene-graft-maleic anhydride as a compatibilizer. The internal morphology, interfacial and thermal characteristics, viscoelastic behavior, water sorption\/wettability, and mechanical properties of composites were studied using electron microscopy, high-resolution synchrotron Fourier transform infrared microspectroscopy, thermal analysis, rheology, immersion test, contact angle measurement, tensile test and flexural test. The composite matrix exhibited an internal morphology of coalescent micro-droplets due to the presence of polyethylene and dry paint in the rPP phase. In general, the rheological and mechanical properties of the composites comprising higher-aspect-ratio (lower diameter) fibers exhibited relatively superior performance. About an 18% increase in tensile strength and a 39% increase in flexural strength were measured for composites with an optimal fiber loading of 10 wt.%. Interfacial debonding and fiber pull-out were observed as the main failure mechanism of the composites. The developed composites have potential for applications in automotive, decking, and building industries.<\/jats:p>","DOI":"10.3390\/polym16182631","type":"journal-article","created":{"date-parts":[[2024,9,18]],"date-time":"2024-09-18T09:43:13Z","timestamp":1726652593000},"page":"2631","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Upcycling Post-Consumer Paint Pail Plastic Waste"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2748-8734","authenticated-orcid":false,"given":"Rajkamal","family":"Balu","sequence":"first","affiliation":[{"name":"Chemical and Environmental Engineering, School of Engineering, STEM College, RMIT University, Melbourne, VIC 3000, Australia"},{"name":"ARC Industrial Transformation Research Hub for Transformation of Reclaimed Waste into Engineered Materials and Solutions for a Circular Economy (TREMS), RMIT University, Melbourne, VIC 3000, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Swati","family":"Sharma","sequence":"additional","affiliation":[{"name":"Paintback Limited, South West Suite, Level 3, 717 Bourke St, Docklands, VIC 3008, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachael","family":"Roberts","sequence":"additional","affiliation":[{"name":"Paintback Limited, South West Suite, Level 3, 717 Bourke St, Docklands, VIC 3008, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0699-3464","authenticated-orcid":false,"given":"Jitraporn","family":"Vongsvivut","sequence":"additional","affiliation":[{"name":"ANSTO\u2014Australian Synchrotron, 800 Blackburn Road, Clayton, VIC 3168, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9010-8506","authenticated-orcid":false,"given":"Namita Roy","family":"Choudhury","sequence":"additional","affiliation":[{"name":"Chemical and Environmental Engineering, School of Engineering, STEM College, RMIT University, Melbourne, VIC 3000, Australia"},{"name":"ARC Industrial Transformation Research Hub for Transformation of Reclaimed Waste into Engineered Materials and Solutions for a Circular Economy (TREMS), RMIT University, Melbourne, VIC 3000, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,18]]},"reference":[{"key":"ref_1","unstructured":"OECD (2022). 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