{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T12:40:16Z","timestamp":1759149616206,"version":"3.44.0"},"reference-count":37,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,9,28]],"date-time":"2025-09-28T00:00:00Z","timestamp":1759017600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology, I.P. (FCT, I.P.) FCT\/MCTES","award":["UIDB\/00151\/2020"],"award-info":[{"award-number":["UIDB\/00151\/2020"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Polymers"],"abstract":"<jats:p>Thermoset fibre-reinforced composites are widely used in high-end industries, but a growing demand for more sustainable and recyclable alternatives conveyed the research efforts towards thermoplastics. To expand their usage, new approaches to their manufacture and mechanical performance must be tackled and tailored to each engineering challenge. The present study designed, manufactured and tested advanced multi-layer laminated composites of thermoplastic polypropylene prepreg reinforced with continuous woven fibreglass with interlayer toughening through thermoplastic polyurethane elastomer (TPU) layers manufactured by fused filament fabrication. The manufacturing process was iteratively optimized, resulting in successful adhesion between layers. Three composite configurations were produced: baseline glass fibre polypropylene (GFPP) prepreg and two multi-layer composites, with solid and honeycomb structured TPU layers. Thermal and mechanical analyses were conducted with both the polyurethane elastomer and the manufactured laminates. Tensile testing was conducted on additively manufactured polyurethane elastomer specimens, while laminated composites were tested in three-point bending. The results demonstrated the potential of the developed laminates. TPU multi-layer laminates exhibit higher thermal stability compared to the baseline GFPP prepreg-based composites. The addition of elastomeric layers decreases the flexural modulus but increases the ability to sustain plastic deformation. Multi-layer laminate composites presenting honeycomb TPU layers exhibit improved geometric and mechanical consistency, lower delamination and fibre breakage, and a high elastic recoverability after testing.<\/jats:p>","DOI":"10.3390\/polym17192622","type":"journal-article","created":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T11:40:52Z","timestamp":1759146052000},"page":"2622","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Multi-Layer Laminate of Fibreglass Thermoplastic Composite Reinforced with Fused Filament Fabrication TPU Layers"],"prefix":"10.3390","volume":"17","author":[{"given":"Ana Paula","family":"Duarte","sequence":"first","affiliation":[{"name":"Atl\u00e2ntica\u2014Instituto Universit\u00e1rio, F\u00e1brica da P\u00f3lvora de Barcarena, 2730-036 Barcarena, Portugal"},{"name":"CERENA\u2014Centro de Recursos Naturais e Ambiente, Instituto Superior T\u00e9cnico, Av. Rovisco Pais, n\u00ba 1, 1049-001 Lisboa, Portugal"},{"name":"C-MAST\u2014Centre for Mechanical and Aerospace Science and Technologies, Universidade da Beira Interior, Convento de Sto. Ant\u00f3nio, 6201-001 Covilh\u00e3, Portugal"}]},{"given":"Pedro R.","family":"da Costa","sequence":"additional","affiliation":[{"name":"Atl\u00e2ntica\u2014Instituto Universit\u00e1rio, F\u00e1brica da P\u00f3lvora de Barcarena, 2730-036 Barcarena, Portugal"},{"name":"C-MAST\u2014Centre for Mechanical and Aerospace Science and Technologies, Universidade da Beira Interior, Convento de Sto. Ant\u00f3nio, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3525-9218","authenticated-orcid":false,"given":"Manuel","family":"Freitas","sequence":"additional","affiliation":[{"name":"Atl\u00e2ntica\u2014Instituto Universit\u00e1rio, F\u00e1brica da P\u00f3lvora de Barcarena, 2730-036 Barcarena, Portugal"},{"name":"C-MAST\u2014Centre for Mechanical and Aerospace Science and Technologies, Universidade da Beira Interior, Convento de Sto. Ant\u00f3nio, 6201-001 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Jiang, L., Zhou, Y., Jin, F., and Hou, Z. (2023). Influence of Polymer Matrices on the Tensile and Impact Properties of Long Fiber-Reinforced Thermoplastic Composites. 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