{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T22:15:23Z","timestamp":1769120123192,"version":"3.49.0"},"reference-count":46,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T00:00:00Z","timestamp":1768867200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Glass fiber-reinforced polymer (GFRP) composites are widely used in structural applications due to their high specific strength and durability; however, their mechanical performance strongly depends on fiber architecture and environmental exposure. This study evaluates the mechanical behavior and moisture-induced degradation of GFRP laminates through tensile tests, impact tests, dynamic mechanical analysis (DMA), and thermomechanical analysis (TMA) performed on a bi-directional glass\u2013epoxy GFRP laminate ([0\u00b0\/90\u00b0]). Tensile tests revealed a maximum longitudinal strength of 369 MPa in dry specimens, while water immersion for up to 21 days led to a significant reduction in tensile strength, from 207 MPa to 63 MPa, in diagonally cut specimens. Impact tests conducted at 12 J showed larger displacements in specimens cut along directions not aligned with the fibers, indicating matrix-dominated behavior. Dynamic mechanical analysis demonstrated strong dependence of stiffness on fiber orientation, with storage modulus values decreasing by approximately 45% in 45\u00b0 specimens compared with the principal directions, while the glass transition temperature remained within 59\u201362 \u00b0C. Thermomechanical analysis confirmed an increase in the coefficient of thermal expansion after aging, from 205.6 to 291.65 \u00b5m\/(m\u00b7\u00b0C) below Tg. These results provide insights into the structure\u2013property\u2013environment relationships governing the durability of GFRP composites and support the optimization of their design for long-term polymer-based applications.<\/jats:p>","DOI":"10.3390\/polym18020277","type":"journal-article","created":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T17:20:42Z","timestamp":1768929642000},"page":"277","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Experimental Evaluation of Tensile Behavior and Hygrothermal Degradation of Glass Fiber Composites"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6300-2255","authenticated-orcid":false,"given":"Ciprian Ionu\u021b","family":"Mor\u0103ra\u0219","sequence":"first","affiliation":[{"name":"Mechanical Engineering, Mechatronics and Robotics Department, Mechanical Engineering Faculty, \u201cGheorghe Asachi\u201d Technical University of Iasi, 700050 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1693-5076","authenticated-orcid":false,"given":"Viorel","family":"Goan\u021b\u0103","sequence":"additional","affiliation":[{"name":"Mechanical Engineering, Mechatronics and Robotics Department, Mechanical Engineering Faculty, \u201cGheorghe Asachi\u201d Technical University of Iasi, 700050 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6792-4425","authenticated-orcid":false,"given":"Lucia Raluca","family":"Maier","sequence":"additional","affiliation":[{"name":"Composite Materials Laboratory for Aeronautical Field, Romanian Research & Development Institute for Gas Turbines\u2014COMOTI, 220D Iuliu Maniu Av., 061126 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7772-1207","authenticated-orcid":false,"given":"Teodor Adrian","family":"Badea","sequence":"additional","affiliation":[{"name":"Composite Materials Laboratory for Aeronautical Field, Romanian Research & Development Institute for Gas Turbines\u2014COMOTI, 220D Iuliu Maniu Av., 061126 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul Doru","family":"B\u00e2rs\u0103nescu","sequence":"additional","affiliation":[{"name":"Mechanical Engineering, Mechatronics and Robotics Department, Mechanical Engineering Faculty, \u201cGheorghe Asachi\u201d Technical University of Iasi, 700050 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rajak, D.K., Pagar, D.D., Menezes, P.L., and Linul, E. 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