Application of azide-containing molecules as modifiers of HTPB

Synthesis and evaluation of properties
  • Maurício Ferrapontoff Lemos
  • Luis Claudio MendesEmail author
  • Manfred Bohn
  • Thomas Keicher


Hydroxyl-terminated polybutadiene (HTPB) has been widely modified and copolymerized with azide substances to be applicable as an elastomer binder in a composite solid propellant (CSP). This research presents a systematic evaluation of the HTPB chemical modification performed with two types of azide-containing molecules such as ethylene glycol bis-(azidoacetate) (EGBAA) and octyl-1-azide. The chemical modification of HTPB was carried out through the bulk reaction between the HTPB double bonds and azide pendant groups. The synthesis was performed by measuring gas evolution in a pressure–vacuum stability device. Through size exclusion chromatography and Fourier-transform infrared spectroscopy, the molar mass and the formation of carbon–nitrogen bonds were evaluated, respectively. Elemental analysis detected nitrogen in the modified HTPB. Differential scanning calorimetry revealed changes in the glass transition temperature (Tg). The final products were dependent on the type of azide molecules. Thermogravimetric analysis showed that HTPB modified with EGBAA presented higher thermal stability. Solid and viscous elastomers were achieved with modification by EGBAA and octyl azide, respectively. Both are potentially suitable for use as binders in CSP.


HTPB Chemical modification Azide molecule Propellant Binder 



Attenuated total reflection with FTIR


Composite solid propellant


Differential scanning calorimetry


Activation energy


Ethylene glycol bis-(azidoacetate)




Fourier-transform infrared spectroscopy


Gas evolution


Gel permeation chromatography


Hydroxyl-terminated polybutadiene


Reaction rate constant of gas evolution


Octyl-1-azide or azido n-octane


Pressure transducer vacuum stability test


Size exclusion chromatography


Standardization agreement (used in NATO)




Thermogravimetric analysis


Pre-exponential factor in Arrhenius equation



The authors would like to thank Universidade Federal do Rio de Janeiro (UFRJ)—Instituto de Macromoléculas Professora Eloisa Mano (IMA), the Instituto de Pesquisas da Marinha (IPqM—Brazil) and the Fraunhofer Institut für Chemische Technologie (Pfinztal, Gemany) for supporting the development of this work.


  1. 1.
    Cerri S, Bohn MA, Menke K, Galfetti L. Characterization of ADN/GAP-based and ADN/desmophen®-based propellant formulations and comparison with AP analogues. Propellants Explos Pyrotech. 2014;39:192–204.CrossRefGoogle Scholar
  2. 2.
    Kubota N. Propellants and explosives thermochemical aspects of combustion. 2nd ed. Weiheim: WILEY-VCH Verlag GmbH & Co. KGaA; 2007.Google Scholar
  3. 3.
    Sbegue LFC, Villar LD. Comparative assessment of stabilised polybutadiene binder under accelerated ageing. J Aerosp Technol Manag. 2016;8:122–9.CrossRefGoogle Scholar
  4. 4.
    Krishnan PSG, Ayyaswamy K, Nayak SK. Hydroxy terminated polybutadiene: chemical modifications and applications review hydroxy terminated polybutadiene—chemical modifications and applications. J Macromol Sci Part A Pure Appl Chem. 2013;50:128–38.CrossRefGoogle Scholar
  5. 5.
    Lemos MF, Bohn MA. DMA of polyester-based polyurethane elastomers for composite rocket propellants containing different energetic plasticizers. J Therm Anal Calorim. 2018;131:595–600.CrossRefGoogle Scholar
  6. 6.
    El-Basuony SA, Sadek MA, Wafy TZ, Mostafa HE. Thermokinetic studies of polyurethanes based on hydroxyl-terminated polybutadiene prepolymer. J Therm Anal Calorim. 2018;131:2013–9.CrossRefGoogle Scholar
  7. 7.
    Lucio B, De La Fuente JL. Rheokinetic analysis on the formation of metallo-polyurethanes based on hydroxyl-terminated polybutadiene. Eur Polym J. 2014;50:117–26.CrossRefGoogle Scholar
  8. 8.
    Mahanta AK, Pathak DD. HTPB-polyurethane : a versatile fuel binder for composite solid propellant. In: Zafar F, Sharmin E, editors. polyurethane. Rijeka: InTech; 2012. p. 229.Google Scholar
  9. 9.
    de Flon J, Andreasson S, Liljedahl M, Oscarson C, Wanhatalo M, Wingborg N. Solid Propellants based on ADN and HTPB. In: 47th AIAA/ASME/SAE/ASEE joint propulsion conference exhibition. San Diego: American Institute of Aeronautics and Astronautics, Inc.; 2011. pp. 1–12.Google Scholar
  10. 10.
    Abusaidi H, Ghaieni HR, Pourmortazavi SM, Motamed-Shariati SH. Effect of nitro content on thermal stability and decomposition kinetics of nitro-HTPB. J Therm Anal Calorim. 2016;124:935–41.CrossRefGoogle Scholar
  11. 11.
    Guery J, Chang I, Shimada T, Glick M, Boury D, Robert E, et al. Solid propulsion for space applications: an updated roadmap. Acta Astronaut. 2010;66:201–19.CrossRefGoogle Scholar
  12. 12.
    Lemos MF, Mussbach G, Bohn MA. Evaluation of filler effects on the dynamic mechanical behavior of HTPB-elastomer used as binder in exemplary composite formulations. J Aerosp Technol Manag. 2017;9:379–88.CrossRefGoogle Scholar
  13. 13.
    Gohardani AS, Stanojev J, Demairé A, Kjell A, Persson M, Wingborg N, et al. Green space propulsion: opportunities and prospects. Prog Aerosp Sci. 2014;71:128–49.CrossRefGoogle Scholar
  14. 14.
    Sciamareli J, Takahashi MFK, Teixeira JM, Iha K. Propelente sólido compósito polibutadiênico: I - Influência do agente de ligação. Quim Nova. 2002;25:107–10.CrossRefGoogle Scholar
  15. 15.
    Nardai M, Bohn M. Molecular dynamics simulation of cohesion within solid propellants. In: 42nd international pyrotechnics society seminars. Grand Junction: IPSUSA Seminars, Inc.; 2016. pp. 306–15.Google Scholar
  16. 16.
    Hafner S, Keicher T, Klapötke TM. Copolymers based on GAP and 1,2-epoxyhexane as promising prepolymers for energetic binder systems. Propellants Explos Pyrotech. 2017;42:1–11.CrossRefGoogle Scholar
  17. 17.
    Huisgen R, Seidel M, Wallbillich G, Knupfer H. Diphenyl-nitrilimin und seine 1.3-dipolaren additionen an alkene und alkine. Tetrahedron. 1962;17:3–29.CrossRefGoogle Scholar
  18. 18.
    Huisgen R, Szeimies G, Mobius L. Kinetik der Additionen organischer Azide an CC Mehrfachbindungen. Chem Ber. 1967;100:2494–507.CrossRefGoogle Scholar
  19. 19.
    Bräse S, Banert K, editors. Organic azides: syntheses and applications. Technology. New York: Wiley; 2010.Google Scholar
  20. 20.
    Bräse S, Gil C, Knepper K, Zimmermann V. Organic azides: an exploding diversity of a unique class of compounds. Angew Chem Int Ed. 2005;44:5188–240.CrossRefGoogle Scholar
  21. 21.
    Lillya CP, Juang R-H, Chien JCW, Miller RS. Synthesis of azido-polymers of butadiene. J Polym Sci. 1982;20:1505–16.Google Scholar
  22. 22.
    Pant CS, Santosh MS, Mehilal, Banerjee S, Khanna PK. Synthesis of azide-functionalized hydroxyl-terminated polybutadiene. In: New trends in research of energetic materials. Pardubice: University of Pardubice; 2015. pp. 229–38.Google Scholar
  23. 23.
    Sankar RM, Roy TK, Jana T. Functionalization of terminal carbon atoms of hydroxyl terminated polybutadiene by polyazido nitrogen rich molecules. Bull Mater Sci. 2011;34:745–54.CrossRefGoogle Scholar
  24. 24.
    Vasudevan V, Sundararajan G. Synthesis of GAP–PB–GAP triblock copolymer and application as modifier in AP a HTPB composite propellant. Propellants Explos Pyrotech. 1999;24:295–300.CrossRefGoogle Scholar
  25. 25.
    Ding Y, Hu C, Guo X, Che Y, Huang J. Structure and mechanical properties of novel composites based on glycidyl azide polymer and propargyl-terminated polybutadiene as potential binder of solid propellant. J Appl Polym Sci. 2014;131:1–8.Google Scholar
  26. 26.
    Subramanian K. Hydroxyl-terminated poly (azidomethyl ethylene oxide-b-butadiene-b-azidomethyl ethylene oxide)-synthesis, characterization and its potential as a propellant binder. Eur Polym J. 1999;35:1403–11.CrossRefGoogle Scholar
  27. 27.
    Filippi S, Mori L, Cappello M, Polacco G. Glycidyl azide-butadiene block copolymers: synthesis from the homopolymers and a chain extender. Propellants Explos Pyrotech. 2017;42:826–35.CrossRefGoogle Scholar
  28. 28.
    Mathew S, Manu SK, Varghese TL. Thermomechanical and morphological characteristics of cross-linked GAP and GAP-HTPB networks with different diisocyanates. Propellants Explos Pyrotech. 2008;33:146–52.CrossRefGoogle Scholar
  29. 29.
    Kawamoto AM, Diniz MF, Lourenço VL, Takahashi MFK, Keicher T, Krause H, et al. Synthesis and characterization of GAP/BAMO copolymers applied at high energetic composite propellants. J Aerosp Technol Manag. 2010;2:307–22.CrossRefGoogle Scholar
  30. 30.
    Gettwert V, Bohn M, Weiser V. Performance of ADN/GAP Propellants Compared to Al/AP/HTPB. In: Insensitive munitions and energetic materials technology symposium. 2015.Google Scholar
  31. 31.
    Reshmi S, Arunan E, Nair CPR. Azide and alkyne terminated polybutadiene binders: synthesis, cross-linking, and propellant studies. Ind Eng Chem Res. 2014;53:16612–20.CrossRefGoogle Scholar
  32. 32.
    Reshmi S, Vijayalakshmi KP, Thomas D, Rajeev R, Reghunadhan Nair CP. Polybutadiene crosslinked by 1,3-dipolar cycloaddition: pyrolysis mechanism, DFT studies and propellant burning rate characteristics. Combust Flame. 2016;167:380–91.CrossRefGoogle Scholar
  33. 33.
    Michejda CJ, Wladkowski BD, Smith RH. Theoretical investigation of the proton-induced decomposition of 4,5-dihydro-1,2,3-triazole to form the aziridinium ion: instability of the (2-aminoethyl)diazonium ion. J Am Chem Soc. 1991;113:7893–7.CrossRefGoogle Scholar
  34. 34.
    Chiba S. Application of organic azides for the synthesis of nitrogen-containing molecules. Synlett. 2012;23:21–44.CrossRefGoogle Scholar
  35. 35.
    Drees D, Loffel D, Messmer A, Schmid K. Synthesis and characterization of azido plasticizer. Propellants Explos Pyrotech. 1999;24:159–62.CrossRefGoogle Scholar
  36. 36.
    Brown OLI, Cary HE, Skinner GS, Wright EJ. The preparation, densities, refractive indices and viscosities of 1-azidoctane, 1-azidoheptane, 1-azidohexane and 1-azidopentane. J Phys Chem. 1957;61:103–4.CrossRefGoogle Scholar
  37. 37.
    Socrates G. Infrared and Raman characteristic group frequencies. 3rd ed. New York: Wiley; 2004.Google Scholar
  38. 38.
    Stuart BH. Infrared spectroscopy: fundamentals and applications. In: Ando DJ, editor. Analytical science and technology. New York: Wiley; 2004.Google Scholar
  39. 39.
    Guyomard A, Fournier D, Pascual S, Fontaine L, Bardeau JF. Preparation and characterization of azlactone functionalized polymer supports and their application as scavengers. Eur Polym J. 2004;40:2343–8.CrossRefGoogle Scholar
  40. 40.
    Patai S, editor. The chemistry of the azido group. New York: Interscience Publishers/Wiley; 1971.Google Scholar
  41. 41.
    Drygina OV, Garnovskii AD. 1,3-dipolar cycloaddition—a general method of synthesis of five-membered nitrogen-containing heterocycles with organoelemental substituents. Russ Chem Rev. 1986;55:851–66.CrossRefGoogle Scholar
  42. 42.
    Krivopalov VP, Shkurko OP. 1,2,3-Triazole and its derivatives. Development of methods for the formation of the triazole ring. Russ Chem Rev. 2005;74:339–79.CrossRefGoogle Scholar
  43. 43.
    Bohn MA, Volk F. Adiabatic self heating of propellants and explosives. In: International ICT annual conference. Karlsruhe: Fraunhofer-Institut fuer Chemische Technologie; 1993. pp. 8–1; 8–26.Google Scholar
  44. 44.
    Kaiser M, Ditz B, Dörich M, Bohn MA. Characterization of several HTPB binder samples by. In: 47th international annual conference on ICT ‘Energetic materials – synthesis characterization, and processing”. Karlsruhe: Fraunhofer-Institut fuer Chemische Technologie; 2016. pp. 55-1–55-33.Google Scholar
  45. 45.
    Lugadet F, Deffieux A, Fontanille M. Synthese de polybutadienes nitres hydroxytelecheliques par nitromercuration-demercuration—II. Etude de la demercuration et caracterisation des polybutadienes nitres. Eur Polym J. 1990;26:1035–40.CrossRefGoogle Scholar
  46. 46.
    Collar EP, Marco C, Laguna O, Areso S, García-Martínez JM. On the changes in glass transition temperatures of atactic polypropylenes induced by grafting of polar groups. J Therm Anal Calorim. 1999;58:541–50.CrossRefGoogle Scholar
  47. 47.
    Fox TG, Flory PJ. Second-order transition temperatures and related properties of polystyrene. I. Influence of molecular weight. J Appl Phys. 1950;21:581–91.CrossRefGoogle Scholar
  48. 48.
    Andrade J, Frutuoso AG, Iha K, Rocco JAFF, Bezerra EM, Matos JR, et al. Estudo da decomposição térmica de propelente sólido compósito de baixa emissão de fumaça. Quim Nova. 2008;31:301–5.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.Instituto de Macromoléculas Professora Eloisa ManoUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil
  2. 2.Instituto de Pesquisas da Marinha - IPqMRio de JaneiroBrazil
  3. 3.Fraunhofer Institute for Chemical Technology ICTPfinztalGermany

Personalised recommendations