{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T00:07:03Z","timestamp":1773706023578,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,6,30]],"date-time":"2025-06-30T00:00:00Z","timestamp":1751241600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52478245"],"award-info":[{"award-number":["52478245"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["24SFP-4"],"award-info":[{"award-number":["24SFP-4"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["Y20240070"],"award-info":[{"award-number":["Y20240070"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Program Fund of Non-Metallic Excellence and Innovation Center for Building Materials","award":["52478245"],"award-info":[{"award-number":["52478245"]}]},{"name":"Program Fund of Non-Metallic Excellence and Innovation Center for Building Materials","award":["24SFP-4"],"award-info":[{"award-number":["24SFP-4"]}]},{"name":"Program Fund of Non-Metallic Excellence and Innovation Center for Building Materials","award":["Y20240070"],"award-info":[{"award-number":["Y20240070"]}]},{"name":"National Foreign Expert Individual Human Project","award":["52478245"],"award-info":[{"award-number":["52478245"]}]},{"name":"National Foreign Expert Individual Human Project","award":["24SFP-4"],"award-info":[{"award-number":["24SFP-4"]}]},{"name":"National Foreign Expert Individual Human Project","award":["Y20240070"],"award-info":[{"award-number":["Y20240070"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Glass fiber reinforced polypropylene composite plates have gradually attracted more attention because of their repeated molding, higher toughness, higher durability, and fatigue resistance compared to glass fiber reinforced thermosetting composites. In practical engineering applications, composite plates have to undergo bending effect at different angles in corrosive environment of concrete, including bending bars from 0~90\u00b0, and stirrups of 90\u00b0, which may lead to long-term performance degradation. Therefore, it is important to evaluate the long-term performance of glass fiber reinforced polypropylene composite bending plates in an alkali environment. In the current paper, a new bending device is developed to prepare glass fiber reinforced polypropylene bending plates with the bending angles of 60\u00b0 and 90\u00b0. It should be pointed out that the above two bending angles are simulated typical bending bars and stirrups, respectively. The plate is immersed in the alkali solution environment for up to 90 days for long-term exposure. Mechanical properties (tensile properties and shear properties), thermal properties (dynamic mechanical properties and thermogravimetric analysis) and micro-morphology analysis (surface morphology analysis) were systematically designed to evaluate the influence mechanism of bending angle and alkali solution immersion on the long-term mechanical properties. The results show the bending effect leads to the continuous failure of fibers, and the outer fibers break under tension, and the inner fibers buckle under compression, resulting in debonding of the fiber\u2013matrix interface. Alkali solution (OH\u2212 ions) corrode the surface of glass fiber to form soluble silicate, which is proved by the mass fraction of glass fiber decreased obviously from 79.9% to 73.65% from thermogravimetric analysis. This contributes to the highest degradation ratio of tensile strength was 71.6% (60\u00b0 bending) and 65.6% (90\u00b0 bending), respectively, compared to the plate with bending angles of 0\u00b0. A high curvature bending angle (such as 90\u00b0) leads to local buckling of fibers and plastic deformation of the matrix, forming microcracks and fiber\u2013resin interface bonding at the bending area, which accelerates the chemical erosion and debonding process in the interface area, bringing about an additional maximum 10.56% degradation rate of the shear strength. In addition, the alkali immersion leads to the obvious degradation of storage modulus and thermal decomposition temperature of composite plate. Compared with the other works on the long-term mechanical properties of glass fiber reinforced polypropylene, it can be found that the long-term performance of glass fiber reinforced polypropylene composites is controlled by the corrosive media type, bending angle and immersion time. The research results will provide durability data for glass fiber reinforced polypropylene composites used in concrete as stirrups.<\/jats:p>","DOI":"10.3390\/polym17131844","type":"journal-article","created":{"date-parts":[[2025,6,30]],"date-time":"2025-06-30T13:06:17Z","timestamp":1751288777000},"page":"1844","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Preparation of Glass Fiber Reinforced Polypropylene Bending Plate and Its Long-Term Performance Exposed in Alkaline Solution Environment"],"prefix":"10.3390","volume":"17","author":[{"given":"Zhan","family":"Peng","sequence":"first","affiliation":[{"name":"Key Lab of Structures Dynamic Behavior and Control, Ministry of Education, Harbin Institute of Technology, Harbin 150090, China"},{"name":"Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters, Ministry of Industry and Information Technology, Harbin Institute of Technology, Harbin 150090, China"},{"name":"School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anji","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Lab of Structures Dynamic Behavior and Control, Ministry of Education, Harbin Institute of Technology, Harbin 150090, China"},{"name":"Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters, Ministry of Industry and Information Technology, Harbin Institute of Technology, Harbin 150090, China"},{"name":"School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chen","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9601-804X","authenticated-orcid":false,"given":"Chenggao","family":"Li","sequence":"additional","affiliation":[{"name":"Key Lab of Structures Dynamic Behavior and Control, Ministry of Education, Harbin Institute of Technology, Harbin 150090, China"},{"name":"Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters, Ministry of Industry and Information Technology, Harbin Institute of Technology, Harbin 150090, China"},{"name":"School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1002\/suco.202200302","article-title":"A practical approach for monitoring reinforcement corrosion in steel fiber reinforced concrete elements exposed to chloride rich environments","volume":"24","author":"Gomez","year":"2023","journal-title":"Struct. 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