{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T05:16:28Z","timestamp":1789190188766,"version":"build-2803163510"},"reference-count":37,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T00:00:00Z","timestamp":1765411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004837","name":"Spanish Ministry of Science and Innovation","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Serra H\u00fanter fellowship"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The present work deals with the preparation and characterization of fire-retardant acrylonitrile\u2013butadiene\u2013styrene (ABS) foams incorporating 25 wt% of a phosphorus flame-retardant (PFR) system formed by 50% of ammonium polyphosphate (APP) and 50% of aluminum diethylphosphinate (AlPi). To further enhance performance, 5 wt% of the PFR was replaced by either montmorillonite (MMT) or layered double hydroxide (LDH) nanoparticles, maintaining the overall FR content constant. The formulations were prepared by melt blending, and foams were produced using a one-step supercritical carbon dioxide (sCO2) dissolution foaming process. The incorporation of the PFR, alone or partially replaced by nanoclays, resulted in foams with smaller cell sizes and higher cell nucleation densities compared to pure ABS, with cell sizes reducing from 60 \u03bcm to as low as 40 \u03bcm and cell densities reaching values &gt; 107 cells\/cm3. The presence of LDH notably modified the thermal decomposition of ABS\u2013PFR, increasing the temperature at 5% mass loss (T5%) by more than 10 \u00b0C and the amount of formed residue by more than 15%. The ABS\u2013PFR\/LDH foam also showed a higher glass transition temperature (3 \u00b0C increase) and a higher specific storage modulus (920 MPa\u00b7cm3\/g, a more than 40% increase). Cone calorimetry revealed a very significant reduction in the peak of the heat release rate (PHRR) and increased residue formation for ABS\u2013PFR compared to ABS (from 1672 kW\u00b7m\u22122 to as low as 483 kW\u00b7m\u22122). LDH nanoparticles further decreased HRR during the early quasi-static combustion stage of foams, indicating a more effective condensed-phase flame-retardant action than MMT.<\/jats:p>","DOI":"10.3390\/polym17243285","type":"journal-article","created":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T11:17:27Z","timestamp":1765451847000},"page":"3285","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Effects of Layered Nanoclays on the Cellular Structure, Dynamic\u2013Mechanical\u2013Thermal Properties and Fire Behavior of Flame-Retardant ABS Foams"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5911-1969","authenticated-orcid":false,"given":"Marcelo","family":"Antunes","sequence":"first","affiliation":[{"name":"Poly2 Group, Department of Materials Science and Engineering, Terrassa School of Industrial, Aerospace and Audiovisual Engineering (ESEIAAT), Technical University of Catalonia (UPC BarcelonaTech), C\/Colom 11, 08222 Terrassa, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3720-6374","authenticated-orcid":false,"given":"Farnaz","family":"Ghonjizade-Samani","sequence":"additional","affiliation":[{"name":"Poly2 Group, Department of Materials Science and Engineering, Terrassa School of Industrial, Aerospace and Audiovisual Engineering (ESEIAAT), Technical University of Catalonia (UPC BarcelonaTech), C\/Colom 11, 08222 Terrassa, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9919-9782","authenticated-orcid":false,"given":"Vera","family":"Realinho","sequence":"additional","affiliation":[{"name":"Poly2 Group, Department of Materials Science and Engineering, Terrassa School of Industrial, Aerospace and Audiovisual Engineering (ESEIAAT), Technical University of Catalonia (UPC BarcelonaTech), C\/Colom 11, 08222 Terrassa, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,11]]},"reference":[{"key":"ref_1","unstructured":"(1994). 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