Flame-retardant surface treatments

Abstract

Flame retardants mitigate the threat of fire from inherently flammable materials responsible for sustaining a high standard of living. Although bulk flame retardants have proven effective for many years, there is now increased interest in the use of surface treatments to localize flame-retardant chemistry at the exterior of a material, where combustion occurs, in an effort to preserve desirable bulk properties and minimize the amount of additive needed. This Review provides a historical overview that leads to the most promising surface treatments that will help pave the way for developing more effective and non-intrusive flame retardants in the future. The way in which a fire transpires, and the various chemistries and mechanisms used to counteract fire propagation, are discussed. Challenges that remain to improve current flame-retardant surface treatments are also addressed, as the success of these treatments depends on the scalability, durability and ability to impart desired functionality without conferring environmental problems.

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Fig. 1: Mechanism for combustion and flame-retardant modes of action.
Fig. 2: Examples of impregnation-based flame-retardant chemistry.
Fig. 3: Plasma-assisted surface treatment.
Fig. 4: Sol–gel surface treatment.
Fig. 5: Polyelectrolyte treatments include layer-by-layer assembled coatings and directly deposited polyelectrolyte coatings.

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The authors acknowledge the worldwide flame retardant scientific community that provided much of the content herein.

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Correspondence to Jaime C. Grunlan.

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Chemical Watch: https://chemicalwatch.com/58037/maine-bans-all-flame-retardants-in-upholstered-furniture

Outright bans on flame retardants: https://chemicalwatch.com/58037/maine-bans-all-flame-retardants-in-upholstered-furniture

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Lazar, S.T., Kolibaba, T.J. & Grunlan, J.C. Flame-retardant surface treatments. Nat Rev Mater 5, 259–275 (2020). https://doi.org/10.1038/s41578-019-0164-6

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