{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T20:01:42Z","timestamp":1790884902911,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,9,24]],"date-time":"2022-09-24T00:00:00Z","timestamp":1663977600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"General Project of Science and Technology Plan of Beijing Municipal Commission of Education","award":["KM202010011001"],"award-info":[{"award-number":["KM202010011001"]}]},{"name":"General Project of Science and Technology Plan of Beijing Municipal Commission of Education","award":["22175006"],"award-info":[{"award-number":["22175006"]}]},{"name":"National Natural Science Foundations","award":["KM202010011001"],"award-info":[{"award-number":["KM202010011001"]}]},{"name":"National Natural Science Foundations","award":["22175006"],"award-info":[{"award-number":["22175006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>A phosphorous-based bi-functional compound HPDAl was used as a reactive-type flame retardant (FR) in an epoxy thermoset (EP) aiming to improve the flame retardant efficiency of phosphorus-based compounds. HPDAl, consisting of two different P-groups of aluminum phosphinate (AHP) and phosphophenanthrene (DOPO) with different phosphorous chemical environments and thus exerting different FR actions, exhibited an intramolecular P-P groups synergy and possessed superior flame-retardant efficiency compared with DOPO or AHP alone or the physical combination of DOPO\/AHP in EP. Adding 2 wt.% HPDAl made EP composites acquire a LOI value of 32.3%, pass a UL94 V-0 rating with a blowing-out effect, and exhibit a decrease in the heat\/smoke release. The flame retardant modes of action of HPDAl were confirmed by the experiments of the scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetry\u2013Fourier transform infrared spectroscopy\u2013gas chromatograph\/mass spectrometer (TG-FTIR-GC\/MS). The results indicate that the phosphorous-based FRs show different influences on the flame retardancy of composites, mainly depending on their chemical structures. HPDAl had a flame inhibition effect in the gas phase and a charring effect in the condensed phase, with a well-balanced distribution of P content in the gas\/condensed phase. Furthermore, the addition of HPDAl hardly impaired the mechanical properties of the matrix due to the link by chemical bonds between them.<\/jats:p>","DOI":"10.3390\/ijms231911256","type":"journal-article","created":{"date-parts":[[2022,9,25]],"date-time":"2022-09-25T23:13:27Z","timestamp":1664147607000},"page":"11256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["A Phosphorous-Based Bi-Functional Flame Retardant Based on Phosphaphenanthrene and Aluminum Hypophosphite for an Epoxy Thermoset"],"prefix":"10.3390","volume":"23","author":[{"given":"Bo","family":"Xu","sequence":"first","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanting","family":"Liu","sequence":"additional","affiliation":[{"name":"China Metallurgical Information and Standardization Research Institute, No. 11, Deng Shi Kou Street, Dongcheng District, Beijing 100730, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simiao","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siheng","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8847-4934","authenticated-orcid":false,"given":"Lijun","family":"Qian","sequence":"additional","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yajun","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Shan","sequence":"additional","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qinglei","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Chemistry and Materials Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"China Light Industry Engineering Technology Research Center of Advanced Flame Retardants, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"},{"name":"Petroleum and Chemical Industry Engineering Laboratory of Non-halogen Flame Retardants for Polymers, No. 11, Fucheng Road, Haidian District, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5012","DOI":"10.1016\/j.polymer.2005.04.025","article-title":"Flame retardant aircraft epoxy resins containing 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Des."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/23\/19\/11256\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:38:45Z","timestamp":1760143125000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/23\/19\/11256"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9,24]]},"references-count":36,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2022,10]]}},"alternative-id":["ijms231911256"],"URL":"https:\/\/doi.org\/10.3390\/ijms231911256","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,9,24]]}}}