Moulded polypropylene foams produced using chemical or physical blowing agents: structure–properties relationship

Abstract

Polypropylene (PP) foams have become essential items due to their excellent properties. Nevertheless, obtaining net-shaped PP foams with medium relative densities is a complicated issue. In this article, two processes able to produce moulded PP foams in this density range are presented. One of them is based on a modification of the pressure quench foaming method and therefore uses a physical blowing agent (CO2). The second one is the improved compression moulding technique which uses a chemical blowing agent (azodicarbonamide). PP foams with relative densities in the range between 0.25 and 0.6 and cylindrical shape were prepared using these foaming techniques. A common PP grade (instead a highly branched one) was used to obtain the samples, showing, that by combining the appropriate foaming technique, the adequate moulds, suitable blowing agent and proper foaming parameters, net-shaped PP foams with excellent properties can be produced starting from a conventional PP grade. Samples were characterized by analyzing their cellular structure and their mechanical properties. Results have showed that depending on the chosen foaming route isotropic or anisotropic structures with cell sizes ranging from 40 to 350 μm and open cell content in the range between 0 and 65% can be obtained. Moreover, mechanical properties are highly influenced by the production route and chemical composition of the foams. For instance, the stiffer materials at relative densities higher than 0.4 are the ones produced using the chemical blowing agent while at relative densities lower than 0.4 are the ones produced using the physical blowing agent.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

References

  1. 1.

    Rodríguez-Pérez MA (2005) Adv Polym Sci 184:1

    Article  Google Scholar 

  2. 2.

    Eaves D (2004) Handbook of polymeric foams. Rapra Technology, Shawbury

    Google Scholar 

  3. 3.

    Klempner D, Sendijarevic V (2004) Handbook of polymeric foams and foam technology, 2nd edn. Hanser Publishers, Munich

    Google Scholar 

  4. 4.

    Naguib HE, Park CB, Song SW (2005) Ind Eng Chem Res 44:6685

    Article  CAS  Google Scholar 

  5. 5.

    Doroudiani S, Park CB, Kortschot MT (1996) Polym Eng Sci 36:2645

    Article  CAS  Google Scholar 

  6. 6.

    Naguib HE, Park CB, Panzer U (2002) Polym Eng Sci 42:1481

    Article  CAS  Google Scholar 

  7. 7.

    Naguib HE, Park CB, Reichelt N (2004) J Appl Polym Sci 91:2661

    Article  CAS  Google Scholar 

  8. 8.

    Xu ZM, Jian XL, Liu T, Hu GH, Zhao L, Zhu ZN, Yuan WK (2007) J Supercrit Fluid 41:299

    Article  CAS  Google Scholar 

  9. 9.

    Park CB, Cheung LK (1997) Polym Eng Sci 37:1

    Article  CAS  Google Scholar 

  10. 10.

    Zheng WG, Lee YH, Park CB (2010) J Appl Polym Sci 117:2972

    CAS  Google Scholar 

  11. 11.

    Zhai W, Kuboki T, Wang L, Park CB, Lee EK, Naguib HE (2010) Ind Eng Chem Res 49:9834

    Article  CAS  Google Scholar 

  12. 12.

    Antunes M, Velasco JI, Realinho V, Solorzano E (2009) Polym Eng Sci 49:2400

    Article  CAS  Google Scholar 

  13. 13.

    Bhattacharya S, Gupta RK, Jollands M, Bhattacharya SN (2009) Polym Eng Sci 49:2070

    Article  CAS  Google Scholar 

  14. 14.

    Jian XL, Liu T, Xu ZM, Zhao L, Hu GH, Yuan WK (2009) J Supercrit Fluid 48:167

    Article  Google Scholar 

  15. 15.

    Zhai W, Wang H, Yu J, Dong JY, He J (2008) Polymer 49:3146

    Article  CAS  Google Scholar 

  16. 16.

    Osswald TA, Turn LS, Gramman PJ (2002) Injection moulding handbook. Hanser Publishers, Munich

    Google Scholar 

  17. 17.

    Lee JWS, Wang J, Yoon JD, Park CB (2008) Ind Eng Chem Res 47:9457

    Article  CAS  Google Scholar 

  18. 18.

    Touleshkow N, Djoumaliisky S, Kotzev G (1989) Polym Degrad Stab 24:327

    Article  Google Scholar 

  19. 19.

    Guo MC, Heuzev MC, Carreau PJ (2007) Polym Eng Sci 47:1070

    Article  CAS  Google Scholar 

  20. 20.

    Okamoto KT (2003) Microcellular processing. Hanser Publishers, Munich

    Google Scholar 

  21. 21.

    Rodríguez-Pérez MA, Lobos J, Pérez-Muñoz CA, de Saja JA (2008) Cell Polym 27:327

    Google Scholar 

  22. 22.

    Rodríguez-Pérez MA, Lobos J, Pérez-Muñoz CA, de Saja JA (2009) J Cell Plast 45:389

    Article  Google Scholar 

  23. 23.

    Rodríguez-Pérez MA, Simoes RD, Roman-Lorza S, Alvarez-Lainez M, Montoya-Mesa C, Constantino CJL, de Saja JA (2011) Polym Eng Sci. doi:10.1002/pen.22046

  24. 24.

    Pinto J, Rodríguez-Pérez MA, de Saja JA (2009) In: XI Reunión del Grupo Especializado de Polímeros (GEP), 10–14 September 2009, Valladolid, Spain

  25. 25.

    Gibson LJ, Ashby MF (1997) Cellular solids: structure and properties. Cambridge University Press, Cambridge

    Google Scholar 

  26. 26.

    Rodríguez-Pérez MA, Alonso O, Duijsens A, de Saja JA (1998) J Appl Polym Sci 36:2587

    Article  Google Scholar 

  27. 27.

    Gong W, Gao J, Jiang M, He L, Yu J, Zhu J (2011) J Appl Polym Sci 122:2907

    Article  CAS  Google Scholar 

Download references

Acknowledgements

Financial assistance from Spanish Ministry of Science and Education and Feder Program (MAT 2009-14001 CO2-01) as well as Innocash Project (INC-0193) and ESA Project AO-99-075 “Advanced foams unless Microgravity” are gratefully acknowledged.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Cristina Saiz-Arroyo.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Saiz-Arroyo, C., de Saja, J.A., Velasco, J.I. et al. Moulded polypropylene foams produced using chemical or physical blowing agents: structure–properties relationship. J Mater Sci 47, 5680–5692 (2012). https://doi.org/10.1007/s10853-012-6357-7

Download citation

Keywords

  • Foam
  • Injection Moulding
  • Expansion Ratio
  • Anisotropy Ratio
  • Cell Size Distribution