{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T03:16:09Z","timestamp":1787800569902,"version":"build-2784847793"},"reference-count":39,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,24]],"date-time":"2022-12-24T00:00:00Z","timestamp":1671840000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Covestro (germany)","award":["2017-2022"],"award-info":[{"award-number":["2017-2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The impact of phosphorus-containing flame retardants (FR) on rigid polyisocyanurate (PIR) foams is studied by systematic variation of the chemical structure of the FR, including non-NCO-reactive and NCO-reactive dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide (BPPO)- and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-containing compounds, among them a number of compounds not reported so far. These PIR foams are compared with PIR foams without FR and with standard FRs with respect to foam properties, thermal decomposition, and fire behavior. Although BPPO and DOPO differ by just one oxygen atom, the impact on the FR properties is very significant: when the FR is a filler or a dangling (dead) end in the PIR polymer network, DOPO is more effective than BPPO. When the FR is a subunit of a diol and it is fully incorporated in the PIR network, BPPO delivers superior results.<\/jats:p>","DOI":"10.3390\/ma16010172","type":"journal-article","created":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T02:55:07Z","timestamp":1672109707000},"page":"172","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Effective Halogen-Free Flame-Retardant Additives for Crosslinked Rigid Polyisocyanurate Foams: Comparison of Chemical Structures"],"prefix":"10.3390","volume":"16","author":[{"given":"Johannes U.","family":"Lenz","sequence":"first","affiliation":[{"name":"Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4209-1759","authenticated-orcid":false,"given":"Doris","family":"Pospiech","sequence":"additional","affiliation":[{"name":"Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6176-6737","authenticated-orcid":false,"given":"Hartmut","family":"Komber","sequence":"additional","affiliation":[{"name":"Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Korwitz","sequence":"additional","affiliation":[{"name":"Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oliver","family":"Kobsch","sequence":"additional","affiliation":[{"name":"Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maxime","family":"Paven","sequence":"additional","affiliation":[{"name":"Covestro Deutschland AG, Kaiser-Wilhelm-Allee 60, 51365 Leverkusen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rolf W.","family":"Albach","sequence":"additional","affiliation":[{"name":"Covestro Deutschland AG, Kaiser-Wilhelm-Allee 60, 51365 Leverkusen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"G\u00fcnther","sequence":"additional","affiliation":[{"name":"Bundesanstalt f\u00fcr Materialforschung und-Pr\u00fcfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5726-9754","authenticated-orcid":false,"given":"Bernhard","family":"Schartel","sequence":"additional","affiliation":[{"name":"Bundesanstalt f\u00fcr Materialforschung und-Pr\u00fcfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1557\/mrs2003.83","article-title":"Aluminum Foams: On the Road to Real Applications","volume":"28","author":"Banhart","year":"2003","journal-title":"MRS Bull."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"17170","DOI":"10.1021\/acs.iecr.8b04799","article-title":"Development of a Bead Foam from an Engineering Polymer with Addition of Chain Extender: Expanded Polybutylene Terephthalate","volume":"57","author":"Standau","year":"2018","journal-title":"Ind. 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