A systematic approach was used to investigate the weathering-induced degradation of a common water–based intumescent coating. In this study, the coatings are intended for humid indoor applications on steel substrates. The coating contains ammonium polyphosphate, pentaerythritol, melamine, and polyvinyl acetate. By replacing each ingredient with a less water-soluble substance, the most vulnerable substances, polyvinyl acetate and pentaerythritol, were identified. Furthermore, the weathering resistance of the system was improved by exchanging the ingredients. The coatings were stressed by artificial weathering tests and evaluated by fire tests. Thermogravimetry and Fourier-transform infrared spectroscopy were used to study the thermal decomposition. This study lays the foundation for the development of a new generation of water-based intumescent coatings.
AlongiJHanZBourbigotS. Intumescence: tradition versus novelty: a comprehensive review. Prog Polym Sci2015; 51: 28–73.
2.
MaciulaitisRGrigonisMMalaiskieneJ. The impact of the aging of intumescent fire protective coatings on fire resistance. Fire Safe J2018; 98: 15–23.
3.
AneesSMDasariA. A review on the environmental durability of intumescent coatings for steels. J Mater Sci2018; 98: 15–23.
4.
AnderssonALundmarkSMaurerFSHJ. Evaluation and characterization of ammonium polyphosphate-pentaerythritol based system for intumescent coatings. J Appl Polym Sci2007; 104: 748–753.
5.
MorganABGilmanJW. An overview of flame retardancy of polymeric materials: application, technology, and future directions. Fire Mater2013; 37: 259–279.
6.
DasariAYuZZCaiPP, et al. Recent developments in the fire retardancy of polymeric materials. Prog Polym Sci2013; 38: 1357–1387.
7.
WangGYangJ. Thermal degradation study of fire resistive coating containing melamine polyphosphate and dipentaerythritol. Prog Organ Coatings2011; 72: 605–611.
CaminoGCostaLLuda di CortemigiaMP. Overview of fire retardant mechanisms. Polym Degrad Stabil1991; 33: 131–154.
10.
CaminoGCostaLTrossarelliL. Study of the mechanism of intumescence in fire retardant polymers: Part IV—evidence of ester formation in ammonium polyphosphate-pentaerythritol mixtures. Polym Degrad Stabil1984; 8: 13–22.
11.
CaminoGCostaLTrossarelliL. Study of the mechanism of intumescence in fire retardant polymers: Part VI—mechanism of ester formation in ammonium polyphosphate-pentaerythritol mixtures. Polymer Degrad Stabil1985; 12: 213–228.
12.
CaminoGCostaL. Performance and mechanism of fire retardants in polymers—a review. Polymer Degrad Stabil1988; 20: 271–294.
13.
VandersallH. Intumescent coating systems, their development and chemistry. J Fire Flamm1971; 2: 97–140.
14.
MorysMIllerhausBSturmH, et al. Revealing the inner secrets of intumescence: advanced standard time temperature oven (STT Mufo+)—µ-computed tomography approach. Fire Mater2017; 41: 927–939.
15.
MorysMIllerhausBSturmH, et al. Size is not all that matters: residue thickness and protection performance of intumescent coatings made from different binders. J Fire Sci2017; 35(4): 284–302.
16.
QinZLiDZhangW, et al. Surface modification of ammonium polyphosphate with vinyltrimethoxysilane: preparation, characterization, and its flame retardancy in polypropylene. Polym Degrad Stab2015; 119: 139–150.
17.
WangZWuKHuY. Study on flame retardance of co-microencapsulated ammonium polyphosphate and dipentaerythritol in polypropylene. Polym Eng Sci2008; 48: 2426–2431.
18.
MariappanT. Recent developments of intumescent fire protection coatings for structural steel: a review. J Fire Sci2015; 34(2): 120–163.
19.
SunLQuYLiS. Co-microencapsulate of ammonium polyphosphate and pentaerythritol and kinetics of its thermal degradation. Polymer Degrad Stabil2012; 97: 404–409.
20.
RimezBRahierHBiesemansM, et al. Flame retardancy and degradation mechanism of poly(vinyl acetate) in combination with intumescent flame retardants: I. Ammonium Polyphosphate. Polymer Degrad Stabil2015; 121: 321–330.
21.
WeilED. Fire-protective and flame-retardant coatings—a state-of-the-art review. J Fire Sci2010; 29: 259–296.
22.
BahraniBHemmatiVZhouA, et al. Effects of natural weathering on the fire properties of intumescent fire-retardant coatings. Fire Mater2018; 42: 413–423.
23.
DongYWangGSuQ, et al. Influence of degree of polymerization of ammonium polyphosphate on anti-aging property of waterborne fire resistive coatings. Surf Coat Technol2013; 246: 71–76.
24.
WangLLWangYCLiGQ, et al. Experimental study of hydrothermal aging effects on insulative properties of intumescent coating for steel elements. Fire Safe J2013; 55: 168–181.
25.
WangBShengHShiY, et al. Recent advances for microencapsulation of flame retardant. Polymer Degrad Stabil2015; 113: 96–109.
26.
DausLHSchartelBKorzenM. High-throughput fire tests and weathering-induced degradation behaviour of intumescent coatings. In: 3rd European symposium on fire safety science, Nancy, 12–14 September 2018, Journal of Physics Conference Series 1107, p. 032014. Bristol: IOP Publishing.
27.
JiangZLiuG. Microencapsulation of ammonium polyphosphate with melamine-formaldehyde-tris(2-hydroxyethyl) isocyanurate resin and its flame retardancy in polypropylene. Royal Soc Chem2015; 5: 88445–88455.
28.
ChenMXuYChenX, et al. Thermal stability and combustion behavior of flame retardant polypropylene with thermoplastic polyurethane-microencapsulated ammonium polyphosphate. High Perform Polym2014; 26(4): 445–454.
29.
DengCLDuSLZhaoJ, et al. An intumescent flame retardant polypropylene system with simultaneously improved flame retardancy and water resistance. Polym Degrad Stabil2014; 108: 97–107.
30.
CaoKWuSLWangKL, et al. Kinetic study on surface modification of ammonium polyphosphate with melamine. Ind Eng Chemis Res2011; 50(14): 8402–8406.
31.
ShaoZBDengCTanY, et al. Flame retardation of polypropylene via a novel intumescent flame retardant: ethylenediamine-modified ammonium polyphosphate. Polym Degrad Stabil2014; 106: 88–96.
32.
LiuZDaiMHuQ, et al. Effect of microencapsulated ammonium polyphosphate on the durability and fire resistance of waterborne intumescent fire-retardant coatings. J Coat Technol Res2019; 16(1): 135–145.
33.
DIN EN 10025-1:2005-4. Hot rolled products of structural steels—Part 1: general technical delivery conditions.
34.
ETAG 018:2012. Teil 2: Reaktive Brandschutzbeschichtungen auf Stahlbauteilen vom18.
35.
BrehmeSKöpplTSchartelB, et al. Competition in aluminium phosphinate-based halogen-free flame retardancy of poly(butylene terephthalate) and its glass-fibre composites. E-polymers2014; 14(3): 193–208.
36.
DIN EN 1363:2012, Fire Resistance Tests—Part 1: General Requirements.
37.
KrügerSGluthGJGWatollaM-B, et al. New ways: reactive fire protection coatings for extreme conditions. Bautechnik2016; 93(8): 531–542.
38.
WatollaMBGluthGJGSturmP, et al. Intumescent geopolymer-bound coatings for fire protection of steel. J Ceramic Sci Tech2017; 08(3): 351–364.
39.
DIN 4102-8:2003. Fire behavior of building materials and components—part 8: small scale test furnace.
40.
SchaefferD. Einführung in das Kunststoffgebiet. 2nd ed. Leipzig: Geest & Portig K.-G., 1953, pp. 227
41.
HarperCA. Handbook of plastics and elastomers, 1st ed. Baltimore, MD: McGraw-Hill; 1975, pp. 4–49.
42.
DaviesPGuyE. Accelerated aging of polyurethanes for marine applications. Polym Degrad Stabil2007; 92: 1455–1464.
KunzeRSchartelBBartholmaiM, et al. TG-MS and TG-FTIR applied for an unambiguous thermal analysis of intumescent coatings. J Thermal Anal Calorimetr2002; 70: 897–909.
49.
CaminoGCostaLTrossarelliL. Study of the mechanism of intumescence in fire retardant polymers: Part V—mechanism of formation of gaseous products in the thermal degradation of ammonium polyphosphate. Polym Degrad Stabil1985; 12: 203–211.
50.
LiuMLiuYWangQ. Flame-retarded poly(propylene) with melamine phosphate and pentaerythritol/polyurethane composite charring agent. Macromol Mater Eng2007; 292(2): 206–213.
