Thermal degradation and flame retardancy of flexible polyvinyl chloride containing solid superacid

  • Ming GaoEmail author
  • Mei Wan
  • Xuan Zhou


The objective of the present article was to study the thermal degradation behavior and flame retardancy of flexible polyvinyl chloride (PVC) composites containing TiO2/SO 4 2− solid superacid because of its strong catalytic ability for esterification and dehydration. The TiO2/SO 4 2− solid superacid was synthesized by using precipitation immersion method, and its structure was investigated by X-ray diffraction. As expected, the value of limiting oxygen index for PVC/Sb2O3/(TiO2/SO 4 2− ) composite was 32.5% and the char yield of PVC/Sb2O3/(TiO2/SO 4 2− ) composite was significantly improved compared to neat PVC in thermogravimetry tests. In addition, the peak heat release rate and smoke production rate of PVC/Sb2O3/(TiO2/SO 4 2− ) decreased by 14% and 42%, respectively, compared with neat PVC. Moreover, the results of cone calorimetry tests and electron micrograph of char residue showed that the char yield of TiO2/SO 4 2− was enhanced, resulting in a strong char layer structure with outstanding fire retardance cone. In conclusion, the results of this work showed that the addition of solid superacid promoted the decomposition and dehydration of PVC, which formed a compact and continuous char layer on the surface of the material. Hence, the study provides a new perspective for producing composites with excellent flame retardancy and smoke suppression properties of PVC.


Flame retardance Polyvinyl chloride (PVC) Solid superacid Thermal degradation Smoke suppression Cone calorimeter 



Funding was provided by the Fundamental Research Funds for the National Natural Science Foundation (Grant No. 51574124) and the Central Universities (Grant No. 3142017065).


  1. 1.
    Starnes WH Jr. Structural and mechanistic aspects of the thermal degradation of poly(vinyl chloride). Prog Polym Sci. 2002;27:2133–70.CrossRefGoogle Scholar
  2. 2.
    Xu J, Zhang C, Qu H, et al. Zinc hydroxystannate and zinc stannate as flame-retardant agents for flexible poly(vinyl chloride). J Appl Polym Sci. 2005;98(3):1469–75.CrossRefGoogle Scholar
  3. 3.
    Tian CM, Wang H, Liu X, et al. Flame retardant flexible poly(vinyl chloride) compound for cable application. J Appl Polym Sci. 2003;89(11):3137–42.CrossRefGoogle Scholar
  4. 4.
    Coaker AW. Fire and flame retardants for PVC. J Vinyl Addit Technol. 2003;9:108–15.CrossRefGoogle Scholar
  5. 5.
    Wei Q, Yang J, Zhang Y, Chang G, Du B. Determination of antimony (III) in environmental water samples in microemulsion system by the fluorescence quenching method. Talanta. 2002;58:419–26.CrossRefGoogle Scholar
  6. 6.
    Oorts K, Smolders E, Degryse F, Buekers J, Gascó G, Cornelis G, Mertens J. Solubility and toxicity of antimony trioxide (Sb2O3) in soil. Environ Sci Technol. 2008;42:4378–83.CrossRefGoogle Scholar
  7. 7.
    Pan Y, Wang D. One-step hydrothermal synthesis of nano zinc carbonate and its use as a promising substitute for antimony trioxide in flame retardant flexible poly(vinyl chloride). RSC Adv. 2015;5(35):27837–43.CrossRefGoogle Scholar
  8. 8.
    Lu Y, Wu C, Xu S. Mechanical, thermal and flame retardant properties of magnesium hydroxide filled poly(vinyl chloride) composites: the effect of filler shape. Compos Part A. 2018;113:1–11.CrossRefGoogle Scholar
  9. 9.
    Zhang B, Han J. Synthesis of microencapsulated zinc stannate and its application in flame-retardant poly(vinyl chloride) membrane material. Fire Mater Banner. 2018;42(1):109–18.CrossRefGoogle Scholar
  10. 10.
    Pi H, Guo SY, Ning Y. Mechanochemical improvement of the flame-retardant and mechanical properties of zinc borate and zinc borate-aluminum trihydrate-filled poly(vinyl chloride). J Appl Polym Sci. 2003;89(3):753–62.CrossRefGoogle Scholar
  11. 11.
    Ropero-Vega JL. Sulfated titania [TiO2/SO4 2−]: a very active solid acid catalyst for the esterification of free fatty acids with ethanol. Appl Catal A. 2010;379:24–9.CrossRefGoogle Scholar
  12. 12.
    Zhang Z, et al. Thermal degradation behaviors and reaction mechanism of carbon fibreepoxy composite from hydrogen tank by TG-FTIR. J Hazard Mater. 2018;357:73–80.CrossRefGoogle Scholar
  13. 13.
    Ding W, Li J, Tao K. Char strengthened by carbon microspheres formed in situ during combustion of IFR/EVA composites catalyzed by solid super acid. RSC Adv. 2014;4(64):34161.CrossRefGoogle Scholar
  14. 14.
    Gao S, Ji Y, Zhang H, et al. Effects of modified zeolites by solid acid on flame retardant systems of polypropylene properties. Plastics. 2011;6:021.Google Scholar
  15. 15.
    Li Y, et al. Fatty acid methyl ester synthesis catalyzed by solid superacid catalyst SO4 2−/ZrO2-TiO2/La3+. Appl Energy. 2010;87(1):156–9.CrossRefGoogle Scholar
  16. 16.
    Wang H, Jiang L, Wang Y, Zheng Y, Jiao X, Pan D. Synthesis of borneol from α-pinene catalyzed by SO4 2−/TiO2–La3+ nanometer rare-earth solid superacid. Inorg Nano-Met Chem. 2018;48(1):23–30. Scholar
  17. 17.
    Ravi K, Krishnakumar B, Swaminathan M. Efficient, rapid, and solvent-free synthesis of substituted bis(indolyl)methanes using sulfated anatase titania as a solid acid catalyst. Synth React Inorg Met-Org Nano-Met Chem. 2015;45(9):1380–6.CrossRefGoogle Scholar
  18. 18.
    Liao S, Donggen H, Denghua Yu, Yunlan S, Yuan G. Preparation and characterization of ZnO/TiO2, SO4 2−/ZnO/TiO2 photocatalyst and their photocatalysis. J Photochem Photobiol A Chem. 2004;168:7–13.CrossRefGoogle Scholar
  19. 19.
    Bickley R, Gonzalea-Carreno T, Lees J. A structural investigation of titanium dioxide photocatalysts. J Solid State Chem. 1991;92:178–90.CrossRefGoogle Scholar
  20. 20.
    Gao M, Chen S, Wang H, Chai ZH. Design, preparation, and application of a novel, microencapsulated, intumescent, flame-retardant-based mimicking mussel. ACS Publ. 2018;3(6):6888–94.Google Scholar
  21. 21.
    Morgan AB, Bundy M. Cone calorimeter analysis of UL-94V-rated plastics. Fire Mater. 2007;31:257–83.CrossRefGoogle Scholar
  22. 22.
    Kim J, Lee JH. Estimating the fire behavior of wood flooring using a cone calorimeter. J Therm Anal Calorim. 2012;110:677–83.CrossRefGoogle Scholar
  23. 23.
    Han L, et al. Metallic ferrites as flame retardants and smoke suppressants in flexible poly(vinyl chloride). Therm Anal Calorim. 2016;123(1):293–300.CrossRefGoogle Scholar
  24. 24.
    Fang Y, Wang Q, Bai X, Wang W, Cooper PA. Thermal and burning properties of wood flour-poly(vinyl chloride) composite. J Therm Anal Calorim. 2012;109:1577–85.CrossRefGoogle Scholar
  25. 25.
    Ming G, Li J, Zhang X, Yue L, Chai Z. The flame retardancy of epoxy resin including the modified graphene oxide and ammonium polyphosphate. Combust Sci Technol. 2018;190(6):1126–40.CrossRefGoogle Scholar
  26. 26.
    Dong M, Gu X, Zhang S, et al. Effects of acidic sites in HA zeolite on the fire performance of polystyrene composite. Ind Eng Chem Res. 2013;52(26):9145–54.CrossRefGoogle Scholar
  27. 27.
    Kissinger HE. Variation of peak temperature with heating rate in differential thermal analysis. J Res Natl Bur Stand. 1956;57(4):217–21.CrossRefGoogle Scholar
  28. 28.
    Sun Y, et al. Thermal behavior of the flexible polyvinyl chloride including montmorillonite modified with iron oxide as flame retardant. J Therm Anal Calorim. 2018;131:65–70.CrossRefGoogle Scholar
  29. 29.
    Chunming T, Hai W, Xiulan L. Flame retardant flexible poly(vinyl chloride) compound for cable application. J Appl Polym Sci. 2003;89(11):3137–42.CrossRefGoogle Scholar
  30. 30.
    Ning T, Guo SY. Flame-retardant and smoke-suppressant properties of zinc borate and aluminum trihydrate filled rigid PVC. J Appl Polym Sci. 2000;77(14):3119–27.CrossRefGoogle Scholar
  31. 31.
    Gumargalieva KZ. Problems of ageing and stabilization of poly(vinyl chloride). Polym Degrad Stab. 1996;52(1):73–9.CrossRefGoogle Scholar
  32. 32.
    Tian CM, Wang H, Guo HZ. Low-melting sulfate glasses as additives to semirigid PVC and their flame retardant and smoke suppressant properties. J Vinyl Addit Technol. 2003;9(2):69–80.CrossRefGoogle Scholar
  33. 33.
    Knumann R, Bockhorn H. Investigation of the kinetics of pyrolysis of PVC by TG-MS-analysis. Combust Sci Technol. 1994;101(1):285–99.CrossRefGoogle Scholar
  34. 34.
    Gao T, et al. Preparation of zinc hydroxystannate-decorated graphene oxide nanohybrids and their synergistic reinforcement on reducing fire hazards of flexible poly(vinyl chloride). Nanoscale Res Lett. 2016;11:192.CrossRefGoogle Scholar
  35. 35.
    Wang X, Zhang Q. Effect of hydrotalcite on the thermal stability, mechanical properties, rheology and flame retardance of poly(vinyl chloride). Polym Int. 2004;53(6):698–707.CrossRefGoogle Scholar
  36. 36.
    Qi Y, Wu W, Han L, Qu H, Han X, Wang A, Xu J. Using TG-FTIR and XPS to understand thermal degradation and flame-retardant mechanism of flexible poly(vinyl chloride) filled with metallic ferrites. J Therm Anal Calorim. 2015;123(2):1263–71.CrossRefGoogle Scholar
  37. 37.
    Zheng L, Qiao Z, Xu X, Wang L. Effects of γ irradiation on the compression and inter-laminar shear properties of G10 for the BESIII beam pipe supporting flange. Fusion Eng Des. 2017;117:24–9.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.School of Environmental EngineeringNorth China Institute of Science and TechnologyYanjiao, BeijingChina
  2. 2.School of Safety EngineeringNorth China Institute of Science and TechnologyYanjiao, BeijingChina

Personalised recommendations