Journal of Thermal Analysis and Calorimetry

, Volume 133, Issue 3, pp 1471–1480 | Cite as

Preparation of modified fly ash hollow glass microspheres using ionic liquids and its flame retardancy in thermoplastic polyurethane

  • Chuanmei Jiao
  • Hongzhi Wang
  • Xilei Chen


In this article, a new type of flame-retardant HGM@[EOOEMIm][PF6] was prepared by modifying fly ash hollow glass microspheres (HGM) with ionic liquids 1-((ethoxycarbonyl)methyl)-3-methylimidazolium hexafluorophosphate([EOOEMIm][PF6]). The physical and chemical characteristic of HGM@[EOOEMIm][PF6] was tested by scanning electron microscope–energy-dispersive spectrometer and X-ray photoelectron spectroscopy, respectively. The flame-retardant characteristics including heat and smoke production of TPU composites were investigated using cone calorimeter test (CCT) and limiting oxygen index, etc. The CCT results revealed that the heat release rate (HRR), total smoke release, and smoke factor and so on decreased greatly with the addition of HGM@[EOOEMIm][PF6]. For example, when the loading of HGM@[EOOEMIm][PF6] was 0.125 mass%, the peak HRR value of the sample was decreased to 779.3 kW m−2 (TPU2), reduced by 23.7% compared with TPU1 (1021.1 kW m−2) containing the same loading of HGM. The thermal degradation behaviors of TPU composites have also been indicated by thermogravimetric analysis/infrared spectrometry (TG–IR). The TG–IR results showed that HGM@[EOOEMIm][PF6] could not only improve the thermal stability of TPU composites at high temperature, but also reduce the aromatic compounds as the smoke precursors. In all, HGM@[EOOEMIm][PF6] will make a great influence in improving the flame retardancy of TPU.


Hollow glass microspheres [EOOEMIm][PF6Thermoplastic polyurethane Flame retardancy 



The authors gratefully acknowledge the National Natural Science Foundation of China (Nos. 51776101, 51206084), the Major Special Projects of Science and Technology from Shandong Province (2015ZDZX11011), the Natural Science Foundation of Shandong Province (ZR2017MB016), and the Project of the State Administration of Work Safety (shandong-0039-2017AQ).


  1. 1.
    Ahmed Z, Hand D, Watkins M, Sutter L. Combined adsorption isotherms for measuring the adsorption capacity of fly ash in concrete. ACS Sustain Chem Eng. 2014;2:614–20.CrossRefGoogle Scholar
  2. 2.
    Ahmaruzzaman M, Gupta VK. Application of coal fly ash in air quality management. Ind Eng Chem Res. 2012;51:15299–314.CrossRefGoogle Scholar
  3. 3.
    Xu S. The comprehensive utilization of fly ash. Appl Mech Mater. 2013;459:82–6.CrossRefGoogle Scholar
  4. 4.
    Shen Y. A study on the comprehensive utilization of fly ash. Enter Sci Technol Dev. 2010;12:7–10.Google Scholar
  5. 5.
    Liu L, Hu J, Zhuo J, Jiao C, Chen X, Li S. Synergistic flame retardant effects between hollow glass microspheres and magnesium hydroxide in ethylene-vinyl acetate composites. Polym Degrad Stab. 2014;104:87–94.CrossRefGoogle Scholar
  6. 6.
    Hu Y, Mei R, An Z, Zhang J. Silicon rubber/hollow glass microsphere composites: influence of broken hollow glass microsphere on mechanical and thermal insulation property. Compos Sci Technol. 2013;79:64–9.CrossRefGoogle Scholar
  7. 7.
    Jiao Y, Xiao G, Xu W, Zhu R, Lu Y. Factors influencing the deposition of hydroxyapatite coating onto hollow glass microspheres. Mater Sci Eng. 2013;33:2744–51.CrossRefGoogle Scholar
  8. 8.
    Sun L, Wan S, Yu Z, Wang L. Optimization and modeling of preparation conditions of TiO2 nanoparticles coated on hollow glass microspheres using response surface methodology. Sep Purif Technol. 2014;125:156–62.CrossRefGoogle Scholar
  9. 9.
    Jiao C, Wang H, Li S, Chen X. Fire hazard reduction of hollow glass microspheres in thermoplastic polyurethane composites. J Hazard Mater. 2017;332:176–84.CrossRefGoogle Scholar
  10. 10.
    Li J, Luo X, Lin X. Preparation and characterization of hollow glass microsphere reinforced poly(butylene succinate) composites. Mater Des. 2013;46:902–9.CrossRefGoogle Scholar
  11. 11.
    Chen X, Jiang Y, Jiao C. Synergistic effects between hollow glass microsphere and ammonium polyphosphate on flame-retardant thermoplastic polyurethane. J Therm Anal Calorim. 2014;117:857–66.CrossRefGoogle Scholar
  12. 12.
    Wang Y, Ulrich V, Donnelly G, Lorenzini F, Marr A, Marr P. A recyclable acidic ionic liquid gel catalyst for dehydration: comparison with an analogous SILP catalyst. ACS Sustain Chem Eng. 2015;3:792–6.CrossRefGoogle Scholar
  13. 13.
    Ran S, Guo Z, Han L. Effect of Friedel–Crafts reaction on the thermal stability and flammability of high-density polyethylene/brominated polystyrene/graphene nanoplatelet composites. Polym Int. 2014;63(10):1835–41.CrossRefGoogle Scholar
  14. 14.
    Chen X, Feng X, Jiao C. Combustion and thermal degradation properties of flame-retardant TPU based on EMIMPF6. J Therm Anal Calorim. 2017;129(2):1–7.Google Scholar
  15. 15.
    Chen X, Jiang Y, Jiao C. Smoke suppression properties of ferrite yellow on flame retardant thermoplastic polyurethane based on ammonium polyphosphate. J Hazard Mater. 2014;266:114–21.CrossRefGoogle Scholar
  16. 16.
    Zhou K, Zhou G, Hu Y, et al. The influence of cobalt oxide–graphene hybrids on thermal degradation, fire hazards and mechanical properties of thermoplastic polyurethane composites. Compos Part A. 2016;88:10–8.CrossRefGoogle Scholar
  17. 17.
    Chattopadhyay D, Webster D. Thermal stability and flame retardancy of polyurethanes. Prog Polym Sci. 2009;34:1068–133.CrossRefGoogle Scholar
  18. 18.
    Zhou K, Gui Z, Hu Y. The influence of graphene based smoke suppression agents on reduced fire hazards of polystyrene composites. Compos Part A. 2016;80:217–27.CrossRefGoogle Scholar
  19. 19.
    Jiao C, Wang H, Zhang Z, et al. Preparation and properties of an efficient smoke suppressant and flame-retardant agent for thermoplastic polyurethane. Polym Adv Technol. 2017;28:1690–8.CrossRefGoogle Scholar
  20. 20.
    Covaci A, Harrad S, Abdallah MA, et al. Novel brominated flame retardants: a review of their analysis, environmental fate and behaviour. Environ Int. 2011;37:532–56.CrossRefGoogle Scholar
  21. 21.
    Laoutid F, Bonnaud L, Alexandre M, Lopez-Cuesta J, Dubois P. New prospects in flame retardant polymer materials: from fundamentals to nanocomposites. Mater Sci Eng. 2009;63:100–25.CrossRefGoogle Scholar
  22. 22.
    Chen X, Ma C, Jiao C. Synergistic effects between iron-graphene and ammonium polyphosphate in flame-retardant thermoplastic polyurethane. J Therm Anal Calorim. 2016;126:633–42.CrossRefGoogle Scholar
  23. 23.
    Chen X, Jiao C. Synergistic effects of hydroxy silicone oil on intumescent flame retardant polypropylene system. Fire Saf J. 2009;44:1010–4.CrossRefGoogle Scholar
  24. 24.
    Zhou K, Rui G, Qian X. Self-assembly of exfoliated molybdenum disulfide (MoS2) nanosheets and layered double hydroxide (LDH): towards reducing fire hazards of epoxy. J Hazard Mater. 2017;338:343–55.CrossRefGoogle Scholar
  25. 25.
    Zhou K, Qian X, Gao R, et al. Facile synthesis and characterization of a novel silica-molybdenum disulfide hybrid material. J Colloid Interface Sci. 2017;504:158–63.CrossRefGoogle Scholar
  26. 26.
    Ge H, Tang G, Hu W, Wang B, Pan Y, Song L, et al. Aluminum hypophosphite microencapsulated to improve its safety and application to flame retardant polyamide 6. J Hazard Mater. 2015;294:186–94.CrossRefGoogle Scholar
  27. 27.
    Hu W, Yu B, Jiang S, Song L, Hu Y, Wang B. Hyper-branched polymer grafting graphene oxide as an effective flame retardant and smoke suppressant for polystyrene. J Hazard Mater. 2015;300:58–66.CrossRefGoogle Scholar
  28. 28.
    Morgan A, Bundy M. Cone calorimeter analysis of UL-94 V-rated plastics. Fire Mater. 2007;31:257–83.CrossRefGoogle Scholar
  29. 29.
    Jiao C, Zhao X, Song W, Chen X. Synergistic flame retardant and smoke suppression effects of ferrous powder with ammonium polyphosphate in thermoplastic polyurethane composites. J Therm Anal Calorim. 2015;120:1173–81.CrossRefGoogle Scholar
  30. 30.
    Nie S, Peng C, Yuan S, Zhang M. Thermal and flame retardant properties of novel intumescent flame retardant polypropylene composites. J Therm Anal Calorim. 2012;113:865–71.CrossRefGoogle Scholar
  31. 31.
    Wumin-Min K, Shen M, Hu Y, Xing W, Wang X. Thermal degradation and intumescent flame retardation of cellulose whisker/epoxy resin composite. J Therm Anal Calorim. 2011;104:1083–90.CrossRefGoogle Scholar
  32. 32.
    Zhao X, Guerrero F, Llorca J, Wang D. New superefficiently flame-retardant bioplastic poly:flammability, thermal decomposition behavior, and tensile properties. ACS Sustain Chem Eng. 2016;4:202–9.CrossRefGoogle Scholar
  33. 33.
    Liu Y, Pearce E, Weil E. Flame retardancy of dicyandiamide-crosslinked epoxy resins containing phenolphthalein structures and/or a phosphorus containing additive. J Fire Sci. 1999;17:240–58.CrossRefGoogle Scholar
  34. 34.
    Chiu S, Wang W, Chiu S. Flame retardancy of polypropylene filled with ammonium polyphosphate, pentaerythritol and melamine additives. Polymer. 1998;39:1951–5.CrossRefGoogle Scholar
  35. 35.
    Chen X, Liu L, Jiao C, Qian Y, Li S. Influence of ferrite yellow on combustion and smoke suppression properties in intumescent flame-retardant epoxy composites. High Perform Polym. 2014;27:412–25.CrossRefGoogle Scholar
  36. 36.
    Ricciardi M, Antonucci V, Zarrelli M, Giordano M. Fire behavior and smoke emission of phosphate-based inorganic fire-retarded polyester resin. Fire Mater. 2012;36:203–15.CrossRefGoogle Scholar
  37. 37.
    Chen X, Liu L, Zhuo J, Jiao C. Influence of iron oxide green on smoke suppression properties and combustion behavior of intumescent flame retardant epoxy composites. J Therm Anal Calorim. 2014;119:625–33.CrossRefGoogle Scholar
  38. 38.
    Ye L, Qu B. Flammability characteristics and flame retardant mechanism of phosphate intercalated hydrotalcite in halogen-free flame retardant EVA blends. Polym Degrad Stab. 2008;93:918–24.CrossRefGoogle Scholar
  39. 39.
    Yang K, Xu M-J, Li B. Synthesis of N-ethyl triazine–piperazine copolymer and flame retardancy and water resistance of intumescent flame retardant polypropylene. Polym Degrad Stab. 2013;98:1397–406.CrossRefGoogle Scholar
  40. 40.
    Yan Y, Chen L, Jian R, Kong S, Wang Y. Intumescence: an effect way to flame retardance and smoke suppression for polystryene. Polym Degrad Stab. 2012;97:1423–31.CrossRefGoogle Scholar
  41. 41.
    Zhou K, Tang G, Jiang S, et al. Combination effect of MoS2 with aluminum hypophosphite in flame retardant ethylene-vinyl acetate composites. RSC Adv. 2016;6(44):37672–80.CrossRefGoogle Scholar
  42. 42.
    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 Stab. 2015;120:193–202.CrossRefGoogle Scholar
  43. 43.
    Ménard R, Negrell C, Ferry L, Sonnier R, David G. Synthesis of biobased phosphorus-containing flame retardants for epoxy thermosets comparison of additive and reactive approaches. Polym Degrad Stab. 2015;120:300–12.CrossRefGoogle Scholar
  44. 44.
    Pan Y, Zhan J, Pan H, Wang W, Tang G, Song L, et al. Effect of fully biobased coatings constructed via layer-by-layer assembly of chitosan and lignosulfonate on the thermal, flame retardant, and mechanical properties of flexible polyurethane poam. ACS Sustain Chem Eng. 2016;4:1431–8.CrossRefGoogle Scholar
  45. 45.
    Wang Z, Liu Y, Li J. Regulating effects of nitrogenous bases on char structure and flame retardancy of polypropylene/intumescent flame retardant composites. ACS Sustain Chem Eng. 2017;5:2375–83.CrossRefGoogle Scholar
  46. 46.
    Chen X, Jiang Y, Liu J, Jiao C, Qian Y, Li S. Smoke suppression properties of fumed silica on flame-retardant thermoplastic polyurethane based on ammonium polyphosphate. J Therm Anal Calorim. 2015;120:1493–501.CrossRefGoogle Scholar
  47. 47.
    Wang B, Song L, Hong N, Tai Q, Lu H, Hu Y. Effect of electron beam irradiation on the mechanical and thermal properties of intumescent flame retarded ethylene-vinyl acetate copolymer/organically modified montmorillonite nanocomposites. Radiat Phys Chem. 2011;80:1275–81.CrossRefGoogle Scholar
  48. 48.
    Ramani A, Dahoe A. On the performance and mechanism of brominated and halogen free flame retardants in formulations of glass fibre reinforced poly(butylene terephthalate). Polym Degrad Stab. 2014;104:71–86.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.College of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdaoPeople’s Republic of China

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