{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T19:18:03Z","timestamp":1792091883287,"version":"4.4.0"},"reference-count":55,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2024,11,29]],"date-time":"2024-11-29T00:00:00Z","timestamp":1732838400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the implementation of the university research","award":["716\/2024"],"award-info":[{"award-number":["716\/2024"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The increasing complexity and production volume of glass-fiber-reinforced polymers (GFRP) present significant recycling challenges. This paper explores a potential use for mechanically recycled GFRP by blending it with high-density polyethylene (HDPE). This composite could be applied in products such as terrace boards, pipes, or fence posts, or as a substitute filler for wood flour and chalk. Recycled GFRP from post-consumer bus bumpers were ground and then combined with recycled HDPE in a twin-screw extruder at concentrations of 10, 20, 30, and 40 wt%. The study examined the mechanical and structural properties of the resulting composites, including the effects of aging and re-extrusion. The modulus of elasticity increased from 0.878 GPa for pure rHDPE to 1.806 GPa for composites with 40 wt% recycled GFRP, while the tensile strength ranged from 36.5 MPa to 28.7 MPa. Additionally, the porosity increased linearly from 2.65% to 7.44% for composites with 10 wt% and 40 wt% recycled GFRP, respectively. Aging and re-extrusion improved the mechanical properties, with the tensile strength of the 40 wt% GFRP composite reaching 34.1 MPa, attributed to a reduction in porosity by nearly half, reaching 3.43%.<\/jats:p>","DOI":"10.3390\/ma17235875","type":"journal-article","created":{"date-parts":[[2024,12,3]],"date-time":"2024-12-03T10:52:30Z","timestamp":1733223150000},"page":"5875","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Structural and Mechanical Properties of Recycled HDPE with Milled GFRP as a Filler"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4612-1639","authenticated-orcid":false,"given":"Maciej Jan","family":"Spycha\u0142a","sequence":"first","affiliation":[{"name":"Faculty of Mechanical Engineering, Military University of Technology, Kaliskiego 2 St., 00-908 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1568-5431","authenticated-orcid":false,"given":"Paulina","family":"Latko-Dura\u0142ek","sequence":"additional","affiliation":[{"name":"Faculty of Materials Science and Engineering, Warsaw University of Technology, Wo\u0142oska 141 St., 02-507 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2503-6600","authenticated-orcid":false,"given":"Danuta","family":"Miedzi\u0144ska","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Military University of Technology, Kaliskiego 2 St., 00-908 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2793-8555","authenticated-orcid":false,"given":"Kamila","family":"Sa\u0142asi\u0144ska","sequence":"additional","affiliation":[{"name":"Faculty of Materials Science and Engineering, Warsaw University of Technology, Wo\u0142oska 141 St., 02-507 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iga","family":"Cetnar","sequence":"additional","affiliation":[{"name":"Faculty of Materials Science and Engineering, Warsaw University of Technology, Wo\u0142oska 141 St., 02-507 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7494-8975","authenticated-orcid":false,"given":"Arkadiusz","family":"Pop\u0142awski","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Military University of Technology, Kaliskiego 2 St., 00-908 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3694-1342","authenticated-orcid":false,"given":"Anna","family":"Boczkowska","sequence":"additional","affiliation":[{"name":"Faculty of Materials Science and Engineering, Warsaw University of Technology, Wo\u0142oska 141 St., 02-507 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kehinde, O., Ramonu, O.J., Babaremu, K.O., and Justin, L.D. 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