Sheet-like Iron Hydroxyl Phosphate as an effective flame retardant and smoke suppressant for Polyacrylonitrile

Document Type : Reasearch Paper


Department of Chemistry, Amirkabir University of Technology (Tehran Polytechnic), 15875-4413, Tehran, Iran.


A novel, one-step, facile and low-cost strategy was successfully designed to synthesize iron hydroxyl phosphate (IP) nanosheets via solvothermal method using iron (II) sulfate heptahydrate, ethylene glycol, and phosphoric acid. Then, for the first time, the flame retardant and smoke suppressant properties of the IP were studied. The synthesized IP nanosheets were added into the polyacrylonitrile (PAN) matrix, by a solvent blending method, to prepare PAN/IP nanocomposite. The structure and morphology of the IP nanosheets were carefully characterized by X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). In addition, the thermal stability, flame retardancy and fire hazard of the PAN/IP nanocomposite were investigated by thermogravimetric analysis (TGA), cone calorimetry, and UL-94 vertical burning test. The PAN/IP nanocomposite exhibited significantly higher smoke suppression and flame retardancy capability as well as less fire hazards than those of the pure PAN. Moreover, incorporation of the IP into the PAN matrix increased the residual char. These improvements were attributed to the ability of the IP to contribute in formation of effective barrier char layer on the PAN, sheet-like morphology of the IP as well as catalytic activity of the IP in carbon monoxide (CO) oxidation.


  1. Wang D., Zhang Q., Zhou K,. Yang W., Hu Y., Gong X., (2014), The influence of manganese–cobalt oxide/graphene on reducing fire hazards of poly (butylene terephthalate). J. Hazard. Mater. 278: 391-400.
  2. Haghighi Poshtiri A., Taghiyari H. R., Naghi Karimi A., (2013), The optimum level of nano-wollastonite consumption as fire-retardant in poplar wood (Populus nigra). Int. J. Nano Dimens. 4: 141-151.
  3. Zhou K., Gui Z., Hu Y., (2016), The influence of graphene based smoke suppression agents on reduced fire hazards of polystyrene composites. Composite- A: Appl. Sci. Manufact. 80: 217-227.
  4. Dong Y., Gui Z., Hu Y., Wu Y., Jiang S., (2012), The influence of titanate nanotube on the improved thermal properties and the smoke suppression in poly (methyl methacrylate). J. Hazard. Mater. 209: 34-39.
  5. Yan X., Zhou W., Zhao X., Xu J., Liu P., (2016), Preparation, flame retardancy and thermal degradation behaviors of polyacrylonitrile fibers modified with diethylenetriamine and zinc ions. J. Therm. Anal. Calorim. 124: 719-728.
  6. Chen X., Liu L., Jiao C., (2015), Influence of iron oxide brown on smoke suppression properties and combustion behavior of intumescent flameā€retardant epoxy composites. Adv. Polym. Technol. 34: 21516-21521.
  7. Asadi S. Z., Shekarian E., Tarighaleslami A. H., (2015), Preparation and characterization of nano-porous Polyacrylonitrile (PAN) membranes with hydrophilic surface. Int. J. Nano Dimens. 6: 217-226.
  8. Ren Y., Jiang L., Tian T., Liu X., Han Z., (2018), Durable flame retardant polyacrylonitrile fabric via UV-induced grafting polymerization and surface chemical modification. RSC Adv. 8: 41389-41396.
  9. Rahimi-Aghdam T., Shariatinia Z., Hakkarainen M., Haddadi-Asl V., (2020), Nitrogen and phosphorous doped graphene quantum dots: Excellent flame retardants and smoke suppressants for polyacrylonitrile nanocomposites. J. Hazard. Mater. 381: 121013-121018.
  10. Rahimi-Aghdam T., Shariatinia Z., Hakkarainen M., Haddadi-Asl V., (2019), Polyacrylonitrile/N, P co-doped graphene quantum dots-layered double hydroxide nanocomposite: Flame retardant property, thermal stability and fire hazard. Eur. Polym. J. 120: 109256-109262.
  11. Hu W., Yu B., Jiang S.-D., Song L,. Hu Y., Wang B., (2015), Hyper-branched polymer grafting graphene oxide as an effective flame retardant and smoke suppressant for polystyrene. J. Hazard. Mater. 300: 58-66.
  12. Shariatinia Z., Javeri N., Shekarriz S., (2015), Flame retardant cotton fibers produced using novel synthesized halogen-free phosphoramide nanoparticles. Carbohydr. Polym. 118: 183-198.
  13. Wang D.-Y., Liu X.-Q., Wang J.-S., Wang Y.-Z., Stec A. A ., Hull T. R., (2009), Preparation and characterisation of a novel fire retardant PET/α-zirconium phosphate nanocomposite. Polym. Degrad. Stab. 94: 544-549.
  14. Zhang Y., Ren Y., Liu X., Huo T., Qin Y., (2018), Preparation of durable flame retardant PAN fabrics based on amidoximation and phosphorylation. Appl. Surf. Sci. 428: 395-403.
  15. Sang B., Li Z.-w., Li X.-h., Yu L.-g., Zhang Z.-j., (2016), Graphene-based flame retardants: a review. J. Mater. Sci. 51: 8271-8295.
  16. Wang X., Kalali E. N., Wan J.-T., Wang D.-Y., (2017), Carbon-family materials for flame retardant polymeric materials. Prog. Polym. Sci. 69: 22-46.
  17. Shi Y., Yu B., Duan L., Gui Z., Wang B., Hu Y., Yuen R. K., (2017), Graphitic carbon nitride/phosphorus-rich aluminum phosphinates hybrids as smoke suppressants and flame retardants for polystyrene. J. Hazard. Mater. 332: 87-96.
  18. Wang S., Hu Y., Zong R., Tang Y., Chen Z., Fan W., (2004), Preparation and characterization of flame retardant ABS/montmorillonite nanocomposite. Appl. Clay Sci. 25: 49-55.
  19. Gao Y., Wu J., Wang Q., Wilkie C. A., O'Hare D., (2014), Flame retardant polymer/layered double hydroxide nanocomposites. J. Mater. Chem. A. 2: 10996-11016.
  20. Yuan G., Yang B., Chen Y., Jia Y., (2019), Synthesis of a novel multi-structure synergistic POSS-GO-DOPO ternary graft flame retardant and its application in polypropylene. Compos. - A: Appl. Sci. Manuf. 117: 345-356.
  21. Setoudeh N., Jahani S., Kazemipour M., Foroughi M. M., Hassani Nadiki H., (2020), Zeolitic imidazolate frameworks and cobalt-tannic acid nanocomposite modified carbon paste electrode for simultaneous determination of dopamine, uric acid, acetaminophen and tryptophan: Investigation of kinetic parameters of surface electrode and its analytical performance. J. Electroanal. Chem. 863: 114045-114051.
  22. Foroughi M. M., Jahani S., Aramesh-Boroujeni Z., Rostaminasab Dolatabad M., Shahbazkhani K., (2021), Synthesis of 3D cubic of Eu3+/Cu2O with clover-like faces nanostructures and their application as an electrochemical sensor for determination of antiretroviral drug nevirapine. Ceram. Int. 47: 19727-19736.
  23. Foroughi M. M., Jahani S., Aramesh-Boroujeni Z., Vakili Fathabadi M., Hashemipour Rafsanjani H., Rostaminasab Dolatabad M., (2021), Template-free synthesis of ZnO/Fe3O4/Carbon magnetic nanocomposite: Nanotubes with hexagonal cross sections and their electrocatalytic property for simultaneous determination of oxymorphone and heroin. Microchem. J. 170: 106679-106685.
  24. Yinhua D., Foroughi M. M., Aramesh-Boroujeni Z., Jahani S., Peydayesh M., Borhani F, Khatami M., Rohani M., Dusek M., Eigner V., (2020), The synthesis, characterization, DNA/BSA/HSA interactions, molecular modeling, antibacterial properties, and in vitro cytotoxic activities of novel parent and niosome nano-encapsulated Ho(iii) complexes. RSC Adv. 10: 22891-22908.
  25. Foroughi M. M., Ranjbar M., (2017), Microwave-assisted synthesis and characterization photoluminescence properties: a fast, efficient route to produce ZnO/GrO nanocrystalline. J. Mater. Sci.: Mater. Electron. 28: 1359-1363.
  26. Yang Q., Lu S., Shen B., Bao S., Liu Y., (2018), An iron hydroxyl phosphate microoctahedron catalyst as an efficient peroxidase mimic for sensitive and colorimetric quantification of H2O2 and glucose. New J. Chem. 42: 6803-6809.
  27. Yu Y-D, Zhu Y-J., Wu J., (2017), Glycerin-assisted solvothermal synthesis of Fe3(PO4)2(OH)2 microspheres. Mater. Lett. 205: 158-161.
  28. Hajmalek S., Jahani S., Foroughi M. M., (2021), Simultaneous voltammetric determination of tramadol and paracetamol exploiting glassy carbon electrode modified with FeNi3 nanoalloy in biological and pharmaceutical media. Chem. Select 6: 8797-8808.
  29. Song H., Sun Y., Jia X., (2015), Hydrothermal synthesis of iron phosphate microspheres constructed by mesoporous polyhedral nanocrystals. Mater. Charact. 107: 182-188.
  30. Sarguru Nanajundaiah R., Hosur Kumara C., Madanahalli Ankanathappa S., (2022), Surface, structural and optical investigation on Poly Vinyl Alcohol (PVA)/Bi2WO6 nanocomposite films. Int. J. Nano Dimens., 10.22034/ijnd.2022.1946867.2109
  31. Jafarian Z., Nikpassand M., Pourahmad A., Zare Fekri L., (2022), Synthesis of fused Azo-linked 1, 2, 4-Triazole-3-Thione derivatives using Ag2S/RHA-MCM-41 nanocomposite. Int. J. Nano Dimens. 13: 117-125.
  32. Li S., Liu X., Mi R., Liu H., Li Y., Lau W.-M., Mei J., (2014), A facile route to modify ferrous phosphate and its use as an iron-containing resource for LiFePO4 via a polyol process. ACS Appl. Mater. Interf. 6: 9449-9457.
  33. Dittrich B., Wartig K.-A., Hofmann D., Mülhaupt R., Schartel B., (2013), Flame retardancy through carbon nanomaterials: Carbon black, multiwall nanotubes, expanded graphite, multi-layer graphene and graphene in polypropylene. Polym. Degrad. Stab. 98: 1495-1505.
  34. Ghiyasiyan-Arani M., Masjedi-Arani M., Ghanbari D., Bagheri S., Salavati-Niasari M., (2016), Novel chemical synthesis and characterization of copper pyrovanadate nanoparticles and its influence on the flame retardancy of polymeric nanocomposites. Sci. Rep. 6: 25231-25238.
  35. Gudarzifar H., Rezvani A., Sabbaghi S., (2021), Morphological investigation of Graphene Oxide/ Polyacrylamide super-elastic nanocomposite by a solution polymerization process with enhanced rheological property and thermal conductivity. Int. J. Nano Dimens. 12: 20-36.
  36. Ghobadi E., Hemmati M., Khanbabaei G., Shojaei M., Asghari M., (2015), Effect of nanozeolite 13X on thermal and mechanical properties of Polyurethane nanocomposite thin films. Int. J. Nano Dimens. 6: 177-181.
  37. Phuruangrat A., Thongtem T., Thongtem S., (2010), Preparation and characterization of nano-crystalline LiNi0.5Co0.5VO4 by tartate precursor combustion method. Int. J. Nano Dimens. 1: 111-118.
  38. Kardam A., Rohit Raj K., Srivastava S., (2012), Novel nano cellulosic fibers for remediation of heavy metals from synthetic water. Int. J. Nano Dimens. 3: 155-162.
  39. Ren Y., Zhang Y., Gu Y., Zeng Q., (2017), Flame retardant polyacrylonitrile fabrics prepared by organic-inorganic hybrid silica coating via sol-gel technique. Progr. Org. Coat. 112: 225-233.
  40. Porter D., Metcalfe E., Thomas M., (2000), Nanocomposite fire retardants: A review. Fire Mater. 24: 45-52.
  41. Abdi Z., Sedaghat S., (2016), Synthesis and characterization of functionalized single - walled carbon nanotube/ chitosan/polyaniline nanocomposite. Int. J. Nano Dimens. 7: 25-32.
  42. Pethsangave D. A., Khose R. V., Wadekar P. H., Some S., (2017), Deep eutectic solvent functionalized graphene composite as an extremely high potency flame retardant. ACS Appl. Mater. Interf. 9: 35319-35324.
  43. Zhou K., Gui Z., Hu Y., Jiang S., Tang G., (2016), The influence of cobalt oxide–graphene hybrids on thermal degradation, fire hazards and mechanical properties of thermoplastic polyurethane composites. Compos- A: Appl. Sci. Manuf. 88: 10-18.
  44. Yin Z., Cai W., Lu J., Yu B., Wang B., Song L., Hu Y., (2022), Cost-effective graphite felt and phosphorous flame retardant with extremely high electromagnetic shielding. Compos. B Eng. 236: 109819-109825.
  45. Shi X.-H., Li X.-L., Li Y.-M., Li Z., Wang D.-Y., (2022), Flame-retardant strategy and mechanism of fiber reinforced polymeric composite: A review. Compos. B. Eng. 233: 109663-109671.
  46. Shi Y., Long Z., Yu B., Zhou K., Gui Z., Yuen R. K., Hu Y., (2015), Tunable thermal, flame retardant and toxic effluent suppression properties of polystyrene based on alternating graphitic carbon nitride and multi-walled carbon nanotubes. J. Mater. Chem. A 3: 17064-17073.
  47. Qiu Y., Qian L., Feng H., Jin S., Hao J., (2018), Toughening effect and flame-retardant behaviors of phosphaphenanthrene/phenylsiloxane bigroup macromolecules in epoxy thermoset. Macromolec. 51: 9992-10002.
  48. Li M., Wu Z., Ma Z., Schwartz V., Mullins D. R, Dai S., Overbury S. H., (2009), CO oxidation on Au/FePO4 catalyst: Reaction pathways and nature of Au sites. J. Catal. 266: 98-105.