123
Subject Areas :
1 -
Keywords: Intumescent coatings, non-intumescent coatings, nanocomposite, sol-gel method, passive fire protection, formulation optimization,
Abstract :
Fire-retardant and fire-resistant coatings, as one of the most efficient and cost-effective passive protection strategies, play a key role in delaying ignition, reducing heat transfer, and limiting flame spread. This review article aims to systematize the existing knowledge in four main areas: first, the fundamentals and mechanisms of action, distinguishing between two categories of intumescent coatings (forming a swollen char layer with expansion capability of up to 100 times) and non-intumescent coatings (gas-phase mechanism or glassy layer formation). Second, formulation optimization based on industrial experimental evidence, demonstrating that the selection of an appropriate polymer binder, optimal ratio of main components, and nano-clay and reinforcing fiber additives have a direct impact on the thermal stability and integrity of the char layer. Third, emerging technologies such as nanocomposites and the sol-gel method, which, by creating transparent coatings while preserving the aesthetic appearance of the substrate, have significantly expanded the application range of these systems. In the final section, considering the challenges associated with the direct application of coatings onto sensitive substrates (chemical damage, reduced mechanical strength, and aesthetic alterations), the "indirect application" approach onto supporting materials is proposed as a low-impact strategy consistent with the principles of reversibility. Nevertheless, the lack of systematic studies in direct comparison of different formulations and evaluation of the long-term durability of these coatings remains a fundamental gap in current knowledge.
[1] T. Mariappan, "Recent developments of intumescent fire protection coatings for structural steel: A review," Journal of fire sciences, vol. 34, no. 2, pp. 120–163, 2016.
[2] T. Mariappan, "Fire retardant coatings," New technologies in protective coatings, vol. 28, no. 5, 2017.
[3] R. White and M. Dietenberger, "Fire safety of wood construction. Wood handbook‑wood as an engineering material," General technical report FPL‑GTR‑190. Madison: US Department of Agriculture, Forest Service, Forest Products Laboratory, 2010.
[4] M. Jimenez, S. Duquesne, and S. Bourbigot, "Multiscale experimental approach for developing high-performance intumescent coatings," Industrial & engineering chemistry research, vol. 45, no. 13, pp. 4500–4508, 2006.
[5] G. B. Verburg et al., "Water-resistant, oil-based, intumescing fire-retardant coatings. I. Developmental formulations," Journal of the American Oil Chemists Society, vol. 41, no. 10, pp. 670–674, 1964.
[6] C. A. Wilkie and A. B. Morgan, Fire retardancy of polymeric materials. CRC press, 2024.
[7] B. A. L. Östman and E. Mikkola, "European classes for the reaction to fire performance of wood‐based panels," Fire and materials, vol. 34, no. 6, pp. 315–330, 2010.
[8] F. Goldsmith, "Fire retardant coatings: an evaluation of fire retardant coatings as a means of protecting wood panels. doi: http://dx. doi. org/10.14288/1.0103122, Wood 493," ed: April, 2011.
[9] T. Hirata, S. Kawamoto, and T. Nishimoto, "Thermogravimetry of wood treated with water‐insoluble retardants and a proposal for development of fire‐retardant wood materials," Fire and materials, vol. 15, no. 1, pp. 27–36, 1991.
[10] K. G. Pabeliña, C. O. Lumban, and H. J. Ramos, "Plasma impregnation of wood with fire retardants," Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, vol. 272, pp. 365–369, 2012.
[11] Q. Li, P. Jiang, and P. Wei, "Synthesis, characteristic, and application of new flame retardant containing phosphorus, nitrogen, and silicon," Polymer Engineering & Science, vol. 46, no. 3, pp. 344–350, 2006.
[12] R. Mačiulaitis, D. Lipinskas, and K. Lukošius, "Singularity and importance of determination of wood charring rate in fire investigation," 2006.
[13] C. Branca and C. Di Blasi, "Semi-global mechanisms for the oxidation of diammonium phosphate impregnated wood," Journal of Analytical and Applied Pyrolysis, vol. 91, no. 1, pp. 97–104, 2011.
[14] E. Baysal, M. Altinok, M. Colak, S. K. Ozaki, and H. Toker, "Fire resistance of Douglas fir (Pseudotsuga menzieesi) treated with borates and natural extractives," Bioresource technology, vol. 98, no. 5, pp. 1101–1105, 2007.
[15] E. D. Tomak and A. D. Cavdar, "Limited oxygen index levels of impregnated Scots pine wood," Thermochimica acta, vol. 573, pp. 181–185, 2013.
[16] H. Getto and S. Ishihara, "Functionally graded wood in fire endurance with basic nitrogen compounds and phosphoric acid," Fire and materials, vol. 22, no. 2, pp. 77–83, 1998.
[17] Subyakto, T. Kajimoto, T. Hata, S. Ishihara, S. Kawai, and H. Getto, "Improving fire retardancy of fast growing wood by coating with fire retardant and surface densification," Fire and materials, vol. 22, no. 5, pp. 207–212, 1998.
[18] H. L. Lee, G. C. Chen, and R. M. Rowell, "Thermal properties of wood reacted with a phosphorus pentoxide–amine system," Journal of Applied Polymer Science, vol. 91, no. 4, pp. 2465–2481, 2004.
[19] R. Stevens, D. S. Van Es, R. Bezemer, and A. Kranenbarg, "The structure–activity relationship of fire retardant phosphorus compounds in wood," Polymer Degradation and Stability, vol. 91, no. 4, pp. 832–841, 2006.
[20] D. Marney and L. Russell, "Combined fire retardant and wood preservative treatments for outdoor wood applications–a review of the literature," Fire Technology, vol. 44, no. 1, pp. 1–14, 2008.
[21] H. Abd El-Wahab, M. Abd El-Fattah, N. Abd El-Khalik, and C. M. Sharaby, "Synthesis and performance of flame retardant additives based on cyclodiphosph (V) azane of sulfaguanidine, 1, 3-di-[N/-2-pyrimidinylsulfanilamide]-2, 2, 2.4, 4, 4-hexachlorocyclodiphosph (V) azane and 1, 3-di-[N/-2-pyrimidinylsulfanilamide]-2, 4-di [aminoacetic acid]-2, 4-dichlorocyclodiphosph (V) azane incorporated into polyurethane varnish," Progress in Organic Coatings, vol. 74, no. 3, pp. 615–621, 2012.
[22] B. Kandola, A. Horrocks, D. Price, and G. Coleman, "Flame-retardant treatments of cellulose and their influence on the mechanism of cellulose pyrolysis," Journal of Macromolecular Science, Part C: Polymer Reviews, vol. 36, no. 4, pp. 721–794, 1996.
[23] O. Grexa, F. Poutch, D. Manikova, H. Martvonova, and A. Bartekova, "Intumescence in fire retardancy of lignocellulosic panels," Polymer degradation and stability, vol. 82, no. 2, pp. 373–377, 2003.
[24] G. Dobele, I. Urbanovich, A. Zhurins, V. Kampars, and D. Meier, "Application of analytical pyrolysis for wood fire protection control," Journal of Analytical and Applied Pyrolysis, vol. 79, no. 1-2, pp. 47–51, 2007.
[25] H. Qu, W. Wu, H. Wu, Y. Jiao, and J. Xu, "Thermal degradation and fire performance of wood treated with various inorganic salts," Fire and materials, vol. 35, no. 8, pp. 569–576, 2011.
[26] L. Yuan, X. Chen, and Y. Hu, "Combination effect of 4-picolinic acid with 5A zeolite on ammonium polyphosphate flame-retarded sawdust board," Journal of Fire Sciences, vol. 32, no. 3, pp. 230–240, 2014.
[27] L. Richardson and A. Cornelissen, "Fire‐resistant coatings for roof/ceiling deck timbers," Fire and materials, vol. 11, no. 4, pp. 191–194, 1987.
[28] W. Gardner and C. Thomson, "Ignitability and heat‐release properties of forest products," Fire and materials, vol. 15, no. 1, pp. 3–9, 1991.
[29] C.-S. Chou, S.-H. Lin, and C.-I. Wang, "Preparation and characterization of the intumescent fire retardant coating with a new flame retardant," Advanced Powder Technology, vol. 20, no. 2, pp. 169–176, 2009.
[30] F. Carosio, F. Cuttica, L. Medina, and L. A. Berglund, "Clay nanopaper as multifunctional brick and mortar fire protection coating—Wood case study," Materials & Design, vol. 93, pp. 357–363, 2016.
[31] S. M. Fufa, A. Steen‐Hansen, B. P. Jelle, and P. J. Hovde, "Reaction to fire and water vapour resistance performance of treated wood specimens containing TiO2 and clay nanoparticles," Fire and Materials, vol. 38, no. 7, pp. 717–724, 2014.
[32] C.-S. Chuang, K.-C. Tsai, T.-H. Yang, C.-H. Ko, and M.-K. Wang, "Effects of adding organo-clays for acrylic-based intumescent coating on fire-retardancy of painted thin plywood," Applied Clay Science, vol. 53, no. 4, pp. 709–715, 2011.
[33] H. R. Taghiyari, "Fire-retarding properties of nano-silver in solid woods," Wood Science and Technology, vol. 46, no. 5, pp. 939–952, 2012.
[34] A. Haghighi Poshtiri, H. R. Taghiyari, and A. Naghi Karimi, "The optimum level of nano-wollastonite consumption as fire-retardant in poplar wood (Populus nigra)," International Journal of Nano Dimension, vol. 4, no. 2, pp. 141–151, 2013.
[35] J. Liu, R. G. Kutty, Q. Zheng, V. Eswariah, S. Sreejith, and Z. Liu, "Hexagonal boron nitride nanosheets as high-performance binder-free fire-resistant wood coatings," 2016.
[36] L. Vakhitova, K. Kalafat, R. Vakhitov, and V. Drizhd, "Improving the fire-retardant performance of industrial reactive coatings for steel building structures," Heliyon, vol. 10, no. 14, 2024.