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The flame-retardant mechanism of P-containing flame retardants: radical capturing effect in the gaseous phase and char promotion effect in the condensed phase. Reprinted with permission from Ref. [51]. Copyright 2021, Elsevier.
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Polymer matrix is vulnerable to fire hazards and needs to add flame retardants to enhance its performance and make its application scenarios more extensive. At this stage, it is more necessary to add multiple flame-retardant elements and build a multi-component synergistic system. Metal organic frameworks (MOFs) have been studied for nearly three d...
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... the one hand, phosphorus flame retardants can release PO· and PO2· radicals and other reactive radicals such as H·, HO·, and O· generated in the combustion chain reaction burst reaction. On the other hand, phosphorus flame retardants can release some phosphoric acid-containing to promote the dehydration of polymer substrates into carbon, as shown in Figure 5. As the mechanism diagram shows, most conventional phosphorus flame retardants have a single flame-retardant mechanism, while P-N flame retardants can effectively improve the thermal stability and fire safety performance of polymers [52]. ...
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Citations
... The presence of the phosphorus-nitrogen skeleton in their structure allows for a conjugation effect, resulting in exceptional chemical stability and resistance to oxidation even after prolonged exposure to air [16][17][18][19][20]. Studies indicate that coordination compounds formed by combining these derivatives with metals not only display high thermal stability but also effectively suppress the release of heat and smoke during material combustion [21][22][23][24]. Metal elements can catalyze dehydration and chain breakage of the polymer matrix, leading to the formation of a stable carbon layer that effectively suppresses heat and smoke release during combustion. ...
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