{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T22:33:19Z","timestamp":1780957999037,"version":"3.54.1"},"reference-count":48,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,10,29]],"date-time":"2019-10-29T00:00:00Z","timestamp":1572307200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["WU 750\/ 8-1 SCHA 730\/ 15-1"],"award-info":[{"award-number":["WU 750\/ 8-1 SCHA 730\/ 15-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The current trend for future flame retardants (FRs) goes to novel efficient halogen-free materials, due to the ban of several halogenated FRs. Among the most promising alternatives are phosphorus-based FRs, and of those, polymeric materials with complex shape have been recently reported. Herein, we present novel halogen-free aromatic and aliphatic hyperbranched polyphosphoesters (hbPPEs), which were synthesized by olefin metathesis polymerization and investigated them as a FR in epoxy resins. We compare their efficiency (aliphatic vs. aromatic) and further assess the differences between the monomeric compounds and the hbPPEs. The decomposition and vaporizing behavior of a compound is an important factor in its flame-retardant behavior, but also the interaction with the pyrolyzing matrix has a significant influence on the performance. Therefore, the challenge in designing a FR is to optimize the chemical structure and its decomposition pathway to the matrix, with regards to time and temperature. This behavior becomes obvious in this study, and explains the superior gas phase activity of the aliphatic FRs.<\/jats:p>","DOI":"10.3390\/molecules24213901","type":"journal-article","created":{"date-parts":[[2019,10,31]],"date-time":"2019-10-31T05:18:26Z","timestamp":1572499106000},"page":"3901","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Aromatic vs. Aliphatic Hyperbranched Polyphosphoesters as Flame Retardants in Epoxy Resins"],"prefix":"10.3390","volume":"24","author":[{"given":"Jens C.","family":"Markwart","sequence":"first","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany"},{"name":"Graduate School Materials Science in Mainz, Staudinger Weg 9, 55128 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Battig","sequence":"additional","affiliation":[{"name":"Bundesanstalt f\u00fcr Materialforschung und-pr\u00fcfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria M.","family":"Velencoso","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dennis","family":"Pollok","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Polymerforschung, Ackermannweg 10, 55128 Mainz, 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"}]},{"given":"Frederik R.","family":"Wurm","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Alexander, B., Jens, C.M., Frederik, R.W., and Bernhard, S. 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