Journal Home Online First Current Issue Archive For Authors Journal Information 中文版

Engineering >> 2022, Volume 17, Issue 10 doi: 10.1016/j.eng.2020.08.032

An Effective Green Porous Structural Adhesive for Thermal Insulating, Flame-Retardant, and Smoke-Suppressant Expandable Polystyrene Foam

The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE) & State Key Laboratory of Polymer Materials Engineering & National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, Sichuan University, Chengdu 610064, China

Received:2020-03-16 Revised:2020-06-16 Accepted: 2020-08-07 Available online:2022-05-18

Next Previous


To develop an efficient way to overcome the contradiction among flame retardancy, smoke suppression, and thermal insulation in expanded polystyrene (EPS) foams, which are widely used insulation materials in buildings, a novel “green” porous bio-based flame-retardant starch (FRS) coating was designed from starch modified with phytic acid (PA) that simultaneously acts as both a flame retardant and an adhesive. This porous FRS coating has open pores, which, in combination with the closed cells formed by EPS beads, create a hierarchically porous structure in FRS–EPS that results in superior thermal insulation with a lower thermal conductivity of 27.0 mW‧(m·K)−1. The resultant FRS–EPS foam showed extremely low heat-release rates and smoke-production release, indicating excellent fire retardancy and smoke suppression. The specific optical density was as low as 121, which was 80.6% lower than that of neat EPS, at 624. The FRS–EPS also exhibited self-extinguishing behavior in vertical burning tests and had a high limiting oxygen index (LOI) value of 35.5%. More interestingly, after being burnt with an alcohol lamp for 30 min, the top side temperature of the FRS–EPS remained at only 140 °C with ignition, thereby exhibiting excellent fire resistance. Mechanism analysis confirmed the intumescent action of FRS, which forms a compact phosphorus-rich hybrid barrier, and the phosphorus-containing compounds that formed in the gas phase contributed to the excellent flame retardancy and smoke suppression of FRS–EPS. This novel porous biomass-based FRS system provides a promising strategy for fabricating polymer foams with excellent flame retardancy, smoke suppression, and thermal insulation.


Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9

Fig. 10

Fig. 11

Fig. 12

Fig. 13

Fig. 14

Fig. 15


[1]  Široky´ J, Oldewurtel F, Cigler J, Prívara S. Experimental analysis of model predictive control for an energy efficient building heating system. Appl Energy 2011;88(9):3079–87. link1

[2]  Cao ZJ, Liao W, Wang SX, Zhao HB, Wang YZ. Polyurethane foams with functionalized graphene towards high fire-resistance, low smoke release, superior thermal insulation. Chem Eng J 2019;361:1245–54. link1

[3]  Li ME, Wang SX, Han LX, Yuan WJ, Cheng JB, Zhang AN, et al. Hierarchically porous SiO2/polyurethane foam composites towards excellent thermal insulating, flame-retardant and smoke-suppressant performances. J Hazard Mater 2019;375:61–9. link1

[4]  Wang SX, Zhao HB, Rao WH, Huang SC, Wang T, Liao W, et al. Inherently flameretardant rigid polyurethane foams with excellent thermal insulation and mechanical properties. Polymer 2018;153:616–25. link1

[5]  Chen HB, Shen P, Chen MJ, Zhao HB, Schiraldi DA. Highly efficient flame retardant polyurethane foam with alginate/clay aerogel coating. ACS Appl Mater Interfaces 2016;8(47):32557–64. link1

[6]  Xu Q, Jin C, Griffin G, Jiang Y. Fire safety evaluation of expanded polystyrene foam by multi-scale methods. J Therm Anal Calorim 2014;115(2):1651–60. link1

[7]  Raps D, Hossieny N, Park CB, Altstädt V. Past and present developments in polymer bead foams and bead foaming technology. Polymer 2015;56:5– 19. link1

[8]  Wang J, Chow W. A brief review on fire retardants for polymeric foams. J Appl Polym Sci 2005;97(1):366–76. link1

[9]  Tian HZ, Zhu CY, Gao JJ, Cheng K, Hao JM, Wang K, et al. Quantitative assessment of atmospheric emissions of toxic heavy metals from anthropogenic sources in China: historical trend, spatial distribution, uncertainties, and control policies. Atmos Chem Phys 2015;15(17):10127–47. link1

[10]  Zhang H, Kuo YY, Gerecke AC, Wang J. Co-release of hexabromocyclododecane (HBCD) and nano- and microparticles from thermal cutting of polystyrene foams. Environ Sci Technol 2012;46(20):10990–6. link1

[11]  Hong Y, Fang X, Yao D. Processing of composite polystyrene foam with a honeycomb structure. Polym Eng Sci 2015;55(7):1494–503. link1

[12]  Yu B, Liu M, Lu L, Dong X, Gao W, Tang K. Fire hazard evaluation of thermoplastics based on analytic hierarchy process (AHP) method. Fire Mater 2010;34(5):251–60. link1

[13]  Zhou K, Gui Z, Hu Y. The influence of graphene based smoke suppression agents on reduced fire hazards of polystyrene composites. Compos Part A Appl Sci Manuf 2016;80:217–27. link1

[14]  Stec AA, Hull TR. Assessment of the fire toxicity of building insulation materials. Energy Build 2011;43(2–3):498–506. link1

[15]  Glück G, Dietzen FJ, Hahn K, Ehrmann G, inventors. Method for producing expandable polystyrene particles. United States patent 6444714 B1. 2002.

[16]  Levchik SV, Weil ED. New developments in flame retardancy of styrene thermoplastics and foams. Polym Int 2008;57(3):431–48. link1

[17]  Huang J, Zhao Z, Chen T, Zhu Y, Lv Z, Gong X, et al. Preparation of highly dispersed expandable graphite/polystyrene composite foam via suspension polymerization with enhanced fire retardation. Carbon 2019;146:503–12. link1

[18]  Zhang S, Ji W, Han Y, Gu X, Li H, Sun J. Flame-retardant expandable polystyrene foams coated with ethanediol-modified melamine–formaldehyde resin and microencapsulated ammonium polyphosphate. J Appl Polym Sci 2018;135 (28):46471–8. link1

[19]  Cao Bo, Gu X, Song X, Jin X, Liu X, Liu X, et al. The flammability of expandable polystyrene foams coated with melamine modified urea formaldehyde resin. J Appl Polym Sci 2017;134(5):44423–30. link1

[20]  Wang Z, Jiang S, Sun H. Expanded polystyrene foams containing ammonium polyphosphate and nano-zirconia with improved flame retardancy and mechanical properties. Iran Polym J 2017;26(1):71–9. link1

[21]  Sayadi AA, Tapia JV, Neitzert TR, Clifton GC. Effects of expanded polystyrene (EPS) particles on fire resistance, thermal conductivity and compressive strength of foamed concrete. Constr Build Mater 2016;112:716–24. link1

[22]  Zhu ZM, Xu YJ, Liao W, Xu SM, Wang YZ. Highly flame retardant expanded polystyrene foams from phosphorus–nitrogen–silicon synergistic adhesives. Ind Eng Chem Res 2017;56(16):4649–58. link1

[23]  Hamdani-Devarennes S, El Hage R, Dumazert L, Sonnier R, Ferry L, Lopez-Cuesta JM, et al. Water-based flame retardant coating using nano-boehmite for expanded polystyrene (EPS) foam. Prog Org Coat 2016;99:32–46. link1

[24]  Messer A. Mini-review: polybrominated diphenyl ether (PBDE) flame retardants as potential autism risk factors. Physiol Behav 2010;100(3):245–9. link1

[25]  Covaci A, Gerecke AC, Law RJ, Voorspoels S, Kohler M, Heeb NV, et al. Hexabromocyclododecanes (HBCDs) in the environment and humans: a review. Environ Sci Technol 2006;40(12):3679–88. link1

[26]  Li ME, Yan YW, Zhao HB, Jian RK, Wang YZ. A facile and efficient flameretardant and smoke-suppressant resin coating for expanded polystyrene foams. Compos Part B Eng 2020;185:107797–803. link1

[27]  Li X, Chen H, Wang W, Liu Y, Zhao P. Synthesis of a formaldehyde-free phosphorus–nitrogen flame retardant with multiple reactive groups and its application in cotton fabrics. Polym Degrad Stabil 2015;120:193–202. link1

[28]  Zhao S, Malfait WJ, Guerrero-Alburquerque N, Koebel MM, Nyström G. Biopolymer aerogels and foams: chemistry, properties, and applications. Angew Chem Int Ed 2018;57(26):7580–608. link1

[29]  Bergel BF, Dias Osorio S, da Luz LM, Santana RMC. Effects of hydrophobized starches on thermoplastic starch foams made from potato starch. Carbohydr Polym 2018;200:106–14. link1

[30]  Soykeabkaew N, Thanomsilp C, Suwantong O. A review: starch-based composite foams. Compos Part A Appl Sci Manuf 2015;78:246–63. link1

[31]  Shogren R, Lawton J, Doane W, Tiefenbacher K. Structure and morphology of baked starch foams. Polymer 1998;39(25):6649–55. link1

[32]  Wang Z, Li Z, Gu Z, Hong Y, Cheng L. Preparation, characterization and properties of starch-based wood adhesive. Carbohydr Polym 2012;88 (2):699–706. link1

[33]  Zhang Y, Ding L, Gu J, Tan H, Zhu L. Preparation and properties of a starchbased wood adhesive with high bonding strength and water resistance. Carbohyd Polym 2015;115:32–7. link1

[34]  Guo Q, Cao J, Han Y, Tang Y, Zhang X, Lu C. Biological phytic acid as a multifunctional curing agent for elastomers: towards skin-touchable and flame retardant electronic sensors. Green Chem 2017;19(14):3418–27. link1

[35]  Cheng XW, Liang CX, Guan JP, Yang XH, Tang RC. Flame retardant and hydrophobic properties of novel sol-gel derived phytic acid/silica hybrid organic–inorganic coatings for silk fabric. Appl Surf Sci 2018;427:69–80. link1

[36]  Wang PJ, Liao DJ, Hu XP, Pan N, Li WX, Wang DY, et al. Facile fabrication of biobased PNC-containing nano-layered hybrid: preparation, growth mechanism and its efficient fire retardancy in epoxy. Polym Degrad Stabil 2019;159:153–62. link1

[37]  Zhao Y, Li XN, Chen T, Tang QY, Qiu LY, Wang BJ, et al. Preparation and antioxidant activity of phosphorylated polysaccharides from Russula alutacea Fr. Ekoloji 2018;27(105):17–22. link1

[38]  Rupper P, Gaan S, Salimova V, Heuberger M. Characterization of chars obtained from cellulose treated with phosphoramidate flame retardants. J Anal Appl Pyrolysis 2010;87(1):93–8. link1

[39]  Chang X, Chen D, Jiao X. Starch-derived carbon aerogels with highperformance for sorption of cationic dyes. Polymer 2010;51(16):3801–7. link1

[40]  Wang Y, Wu K, Xiao M, Riffat SB, Su Y, Jiang F. Thermal conductivity, structure and mechanical properties of konjac glucomannan/starch based aerogel strengthened by wheat straw. Carbohydr Polym 2018;197:284–91. link1

[41]  Wang YT, Zhao HB, Degracia K, Han LX, Sun H, Sun M, et al. Green approach to improving the strength and flame retardancy of poly(vinyl alcohol)/clay aerogels: incorporating biobased gelatin. ACS Appl Mater Interfaces 2017;9 (48):42258–65. link1

[42]  Rao WH, Zhu ZM, Wang SX, Wang T, Tan Y, Liao W, et al. A reactive phosphorus-containing polyol incorporated into flexible polyurethane foam: self-extinguishing behavior and mechanism. Polym Degrad Stabil 2018;153:192–200. link1

[43]  Liu BW, Chen L, Guo D, Liu X, Lei Y, Ding X, et al. Fire-safe polyesters enabled by end-group capturing chemistry. Angew Chem Int Ed 2019;58(27):9188–93. link1

[44]  Fu T, Zhao X, Chen L, Wu W, Zhao Q, Wang XL, et al. Bioinspired color changing molecular sensor toward early fire detection based on transformation of phthalonitrile to phthalocyanine. Adv Funct Mater 2019;29(8):1806586. link1

[45]  Li P, Wang B, Xu YJ, Jiang Z, Dong C, Liu Y, et al. Ecofriendly flame-retardant cotton fabrics: preparation, flame retardancy, thermal degradation properties, and mechanism. ACS Sustain Chem Eng 2019;7(23):19246–56. link1

[46]  Peng H, Wang D, Fu S. Tannic acid-assisted green exfoliation and functionalization of MoS2 nanosheets: significantly improve the mechanical and flame-retardant properties of polyacrylonitrile composite fibers. Chem Eng J 2020;384:123288. link1

[47]  Zhao HB, Cheng JB, Wang YZ. Biomass-derived Co@crystalline carbon@carbon aerogel composite with enhanced thermal stability and strong microwave absorption performance. J Alloys Compd 2018;736:71–9. link1

[48]  Jian RK, Ai YF, Xia L, Zhao LJ, Zhao HB. Single component phosphamide-based intumescent flame retardant with potential reactivity towards low flammability and smoke epoxy resins. J Hazard Mater 2019;371:529–39. link1

Related Research