Cargando…

Thermal Degradation of Organophosphorus Flame Retardants

The development of new organophosphorus flame retardants for polymeric materials is spurred by relatively low toxicity, effectiveness, and demand for replacement of more traditional materials. To function, these compounds must decompose in a degrading polymer matrix to form species which promote mod...

Descripción completa

Detalles Bibliográficos
Autor principal: Howell, Bob A.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9695522/
https://www.ncbi.nlm.nih.gov/pubmed/36433056
http://dx.doi.org/10.3390/polym14224929
_version_ 1784838081790083072
author Howell, Bob A.
author_facet Howell, Bob A.
author_sort Howell, Bob A.
collection PubMed
description The development of new organophosphorus flame retardants for polymeric materials is spurred by relatively low toxicity, effectiveness, and demand for replacement of more traditional materials. To function, these compounds must decompose in a degrading polymer matrix to form species which promote modification of the solid phase or generate active radical moieties that escape to the gas phase and interrupt combustion propagating reactions. An understanding of the decomposition process for these compounds may provide insight into the nature of flame retardant action which they may offer and suggest parameters for the synthesis of effective new organophosphorus flame retardants. The thermal degradation of a series of organophosphorus esters varying in the level of oxygenation at phosphorus—alkyl phosphate, aryl phosphate, phosphonate, phosphinate—has been examined. Initial degradation in all cases corresponds to elimination of a phosphorus acid. However, the facility with which this occurs is strongly dependent on the level of oxygenation at phosphorus. For alkyl phosphates elimination occurs rapidly at relatively low temperature. The same process occurs at somewhat higher temperature for aryl phosphates. Elimination of a phosphorus acid from phosphonate or phosphinate occurs more slowly and at much higher temperature. Further, the acids formed from elimination rapidly degrade further to evolve volatile species.
format Online
Article
Text
id pubmed-9695522
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-96955222022-11-26 Thermal Degradation of Organophosphorus Flame Retardants Howell, Bob A. Polymers (Basel) Article The development of new organophosphorus flame retardants for polymeric materials is spurred by relatively low toxicity, effectiveness, and demand for replacement of more traditional materials. To function, these compounds must decompose in a degrading polymer matrix to form species which promote modification of the solid phase or generate active radical moieties that escape to the gas phase and interrupt combustion propagating reactions. An understanding of the decomposition process for these compounds may provide insight into the nature of flame retardant action which they may offer and suggest parameters for the synthesis of effective new organophosphorus flame retardants. The thermal degradation of a series of organophosphorus esters varying in the level of oxygenation at phosphorus—alkyl phosphate, aryl phosphate, phosphonate, phosphinate—has been examined. Initial degradation in all cases corresponds to elimination of a phosphorus acid. However, the facility with which this occurs is strongly dependent on the level of oxygenation at phosphorus. For alkyl phosphates elimination occurs rapidly at relatively low temperature. The same process occurs at somewhat higher temperature for aryl phosphates. Elimination of a phosphorus acid from phosphonate or phosphinate occurs more slowly and at much higher temperature. Further, the acids formed from elimination rapidly degrade further to evolve volatile species. MDPI 2022-11-15 /pmc/articles/PMC9695522/ /pubmed/36433056 http://dx.doi.org/10.3390/polym14224929 Text en © 2022 by the author. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Howell, Bob A.
Thermal Degradation of Organophosphorus Flame Retardants
title Thermal Degradation of Organophosphorus Flame Retardants
title_full Thermal Degradation of Organophosphorus Flame Retardants
title_fullStr Thermal Degradation of Organophosphorus Flame Retardants
title_full_unstemmed Thermal Degradation of Organophosphorus Flame Retardants
title_short Thermal Degradation of Organophosphorus Flame Retardants
title_sort thermal degradation of organophosphorus flame retardants
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9695522/
https://www.ncbi.nlm.nih.gov/pubmed/36433056
http://dx.doi.org/10.3390/polym14224929
work_keys_str_mv AT howellboba thermaldegradationoforganophosphorusflameretardants