{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T17:32:05Z","timestamp":1790357525247,"version":"4.1.0"},"reference-count":46,"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\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>While plastics are regarded as the most resourceful materials nowadays, ranging from countless utilities including protective or decorating coatings, to adhesives, packaging materials, electronic components, paintings, furniture, insulating composites, foams, building blocks and so on, their critical limitation is their advanced flammability, which in fire incidents can result in dramatic human fatalities and irreversible environmental damage. Herein, epoxy-based composites with improved flame-resistant characteristics have been prepared by incorporating two flame retardant additives into epoxy resin, namely 6-(hydroxy(phenyl)methyl)-6H-dibenzo[c,e][1,2]oxaphosphinine-6-oxide (PFR) and boric acid (H3BO3). The additional reaction of 9,10-dihydro-oxa-10-phosphophenanthrene-10-oxide (DOPO) to the carbonyl group of benzaldehyde yielded PFR, which was then used to prepare epoxy composites having a phosphorus content ranging from 1.5 to 4 wt%, while the boron content was 2 wt%. The structure, morphology, thermal stability and flammability of resulted epoxy composites were investigated by FTIR spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis, differential scanning calorimetry, and microscale combustion calorimetry (MCC). Thermogravimetric analysis indicated that the simultaneous incorporation of PFR and H3BO3 improved the thermal stability of the char residue at high temperatures. The surface morphology of the char residues, studied by SEM measurements, showed improved characteristics in the case of the samples containing both phosphorus and boron atoms. The MCC tests revealed a significant reduction in flammability as well as a significant decrease in heat release capacity for samples containing both PFR and H3BO3 compared to the neat epoxy thermoset.<\/jats:p>","DOI":"10.3390\/polym14194005","type":"journal-article","created":{"date-parts":[[2022,9,26]],"date-time":"2022-09-26T03:34:17Z","timestamp":1664163257000},"page":"4005","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Effects of Phosphorus and Boron Compounds on Thermal Stability and Flame Retardancy Properties of Epoxy Composites"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9454-4399","authenticated-orcid":false,"given":"Corneliu","family":"Hamciuc","sequence":"first","affiliation":[{"name":"Department of Polycondensation and Thermally Stable Polymers, \u201cPetru Poni\u201d Institute of Macromolecular Chemistry, 41A, Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9017-9926","authenticated-orcid":false,"given":"T\u0103chi\u021b\u0103","family":"Vlad-Bubulac","sequence":"additional","affiliation":[{"name":"Department of Polycondensation and Thermally Stable Polymers, \u201cPetru Poni\u201d Institute of Macromolecular Chemistry, 41A, Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8544-5671","authenticated-orcid":false,"given":"Diana","family":"Serbezeanu","sequence":"additional","affiliation":[{"name":"Department of Polycondensation and Thermally Stable Polymers, \u201cPetru Poni\u201d Institute of Macromolecular Chemistry, 41A, Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5107-6369","authenticated-orcid":false,"given":"Ana-Maria","family":"Macsim","sequence":"additional","affiliation":[{"name":"Department of Polycondensation and Thermally Stable Polymers, \u201cPetru Poni\u201d Institute of Macromolecular Chemistry, 41A, Grigore Ghica Voda Alley, 700487 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4541-7446","authenticated-orcid":false,"given":"Gabriela","family":"Lisa","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Gheorghe Asachi Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, Bd. Mangeron 73, 700050 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ion","family":"Anghel","sequence":"additional","affiliation":[{"name":"Police Academy \u201cAlexandru Ioan Cuza\u201d, Fire Officers Faculty, Morarilor Str. 3, Sector 2, 022451 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioana-Emilia","family":"\u015eofran","sequence":"additional","affiliation":[{"name":"Police Academy \u201cAlexandru Ioan Cuza\u201d, Fire Officers Faculty, Morarilor Str. 3, Sector 2, 022451 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1515\/eng-2021-0078","article-title":"Epoxy resins thermosetting for mechanical engineering","volume":"11","author":"Sukanto","year":"2021","journal-title":"Open Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/15583724.2019.1650063","article-title":"Multifunctionality in Epoxy Resins","volume":"60","author":"Capricho","year":"2020","journal-title":"Polym. 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