Skip to main content
Log in

Preparation and Characterization of DGEBA/EPN Epoxy Blends with Improved Fracture Toughness

  • Article
  • Published:
Chinese Journal of Polymer Science Aims and scope Submit manuscript

Abstract

The physical and mechanical properties of blends composed of two kinds of epoxy resins of different numbers of functional groups and chemical structure were studied. One of the resins was a bifunctional epoxy resin based on diglycidyl ether of bisphenol A and the other resin was a multifunctional epoxy novolac resin. Attempt was made to establish a correlation between the structure and the final properties of cured epoxy samples. The blend samples containing high fraction of multifunctional epoxy resin showed higher solvent resistance and lower flexural modulus compared with the blends containing high fraction of bifunctional epoxy resin. The epoxy blends showed significantly higher ductility under bending test than the neat epoxy samples. The compressive modulus and strength increased with increasing of multifunctional epoxy in the samples, probably due to enhanced cross-link density and molecular weight. Morphological analysis revealed the presence of inhomogeneous sub-micrometer structures in all samples. The epoxy blends exhibited significantly higher fracture toughness (by 23% at most) compared with the neat samples. The improvement of the fracture toughness was attributed to the stick-slip mechanism for crack growth and activation of shear yielding and plastic deformation around the crack growth trajectories for samples with higher content of bifunctional epoxy resin as evidenced by fractography study.

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

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Lee, H.; Neville. K. “Handbook of epoxy resins”, McGraw Hill, New York, 1982, p. 5–1

    Google Scholar 

  2. May, C. A. “Epoxy resins chemistry and technology”, 2nd edn. Marcel Dekker, New York, 1988, p. 551

    Google Scholar 

  3. Hamerton, I. “Recent developments in epoxy resins”, Rapra Review Reports, Shawbury, 1996, 8(7), 58–63.

    Google Scholar 

  4. Pham, H. A. Q.; Marks, M. J. Epoxy resins, in, “Encyclopedia of Polymer Science and Technology”, Vol. 9, 3rd Edition, John Wiley & Sons. 2010, p. 678.

    Google Scholar 

  5. Ratna, D.; Banthia, A. K., Rubber toughened epoxy. Macromol. Res. 2004, 12(1), 11–21.

    Article  CAS  Google Scholar 

  6. Ikram, S.; Munir, A. Mechanical and thermal properties of chemically modified epoxy resin. Open J. Synth. Theory Appl. 2012, 1(3), 36–43.

    Article  CAS  Google Scholar 

  7. Akbari, R.; Beheshty, M. H.; Shervin, M. Toughening of dicy-andiamide-cured DGEBA-based epoxy resins by CTBN liquid. Iran. Polym. J. 2013, 22(5), 313–324.

    Article  CAS  Google Scholar 

  8. Jamshidi, H.; Akbari, R.; Beheshty, M. H. Toughening of dicyandiamide-cured DGEBA-based epoxy resins using flexible diamine rubber. Iran. Polym. J. 2015, 24(5), 399–410.

    Article  CAS  Google Scholar 

  9. Hwang, J. F.; Manson, J. A.; Hertzberg, R. W.; Miller, G. A.; Sperling, L. H. Structure-property relationship in rubbertoughened epoxies. Polym. Eng. Sci. 1989, 29(20), 1466–1476.

    Article  CAS  Google Scholar 

  10. Saadati, P.; Baharvand, H.; Rahimi, A.; Morshedian, J. Effect of modified liquid rubber on increasing toughness of epoxy resins. Iran. Polym. J. 2005, 14(7), 637–646.

    CAS  Google Scholar 

  11. Martinez, I.; Martin, M. D.; Eceiza, A.; Oyanguren, P.; Mondragon, I. Phase separation in polysulfone-modified epoxy mixtures: relationships between curing conditions, morphology and ultimate behavior. Polymer 2000, 41(3), 1027–1035.

    Article  CAS  Google Scholar 

  12. Giannotti, M. I.; Bernal, C. R.; Oyanguren, P. A.; Galante, M. J. Morphology and fracture properties relationship of epoxy-diamine systems simultaneously modified with polysulfone and poly(ether imide). Polym. Eng. Sci. 2005, 45(9), 1312–1318.

    Article  CAS  Google Scholar 

  13. Li, H.; Gan, W.; Zhao, L.; Li, S. Studies on the phase separation of apolyetherimide modified epoxy resin. VI. Effect of surface energy on reaction-induced phase separation of epoxy resinmodified with polyetherimide. J. Macromol. Sci., Part A Pure Appl. Chem. A 2003, 40(8), 833–846.

    Google Scholar 

  14. Andrés, M. A.; Garmendia, J.; Valea, A.; Eceiza, A.; Mondragon, I. Fracture toughness of epoxy resins modified with poly-ethersulfone: influence of stoichiometry on themorphology ofthe mixtures. J. Appl. Polym. Sci. 1998, 69(1), 183–191.

    Article  Google Scholar 

  15. Grishchuk, S.; Gryshchuk, O.; Weber, M.; Karger-Kocsis, J. Structure and toughness of polyethersulfone (PESU)-modifiedanhydride-cured tetrafunctional epoxy resin: effect of PESU molecular mass. J. Appl. Polym. Sci. 2012, 123(2), 1193–1200.

    Article  CAS  Google Scholar 

  16. Ma, S. Q.; Liu, W. Q.; Hu, C. H.; Wang, Z. F. Modification of epoxy resins with polyether-g-polysiloxanes. Iran. Polym. J. 2010, 19(3), 185–196.

    CAS  Google Scholar 

  17. Tong, J. D.; Bai, R. K.; Zou, Y. F.; Pan, C. Y.; Ichimura, S. Flexibility improvement of epoxy-resin by using polysiloxanes and theirderivatives. J. Appl. Polym. Sci. 1994, 52(10), 1373–1381.

    Article  CAS  Google Scholar 

  18. Zhao, F.; Sun, Q. C.; Fang, D. P.; Yao, K. D. Preparation and properties of polydimethylsiloxane-modified epoxy resins. J. Appl. Polym. Sci. 2000, 76(11), 1683–1690.

    Article  CAS  Google Scholar 

  19. Mahnam, N.; Beheshty, M. H.; Barmar, M.; Shervin, M. Modification of dicyandiamide-cured epoxy resin with different molecular weight of polyethylene glycol and its effect on epoxy/glass prepreg characteristic. High Perform. Polym. 2013, 25(6), 705–713.

    Article  Google Scholar 

  20. Sprenger, S. Epoxy resins modified with elastomers and surface-modified silica nanoparticles. Polymer 2013, 54(18), 4790–4797.

    Article  CAS  Google Scholar 

  21. Lee, J.; Yee, A. F. Fracture of glass bead/epoxy composites: on micro-mechanical deformations. Polymer 2000, 41(23), 8363–8373.

    Article  CAS  Google Scholar 

  22. Sahoo, N. G.; Rana, S.; Cho, J. W.; Chan, S. H.; Li, L. Polymer nanocomposites based on functionalized carbon nanotubes. Prog. Polym. Sci. 2010, 35(7), 837–867.

    Article  CAS  Google Scholar 

  23. Rahman, M. M.; Hosur, M.; Zainuddin, S.; Jajam, K. C.; Tippur, H. V.; Jee-lani. S. Mechanical characterization of epoxy compositesmodified with reactive polyol diluents and randomly-oriented amino-functionalized MWCNTs. Polym. Test. 2012, 31(8), 1083–1093.

    Article  CAS  Google Scholar 

  24. Pearson, R. A.; Yee, A. F. Toughening mechanisms in elastomer-modified epoxies: Part 3: The effect of crosslink density. J. Mater. Sci. 1989, 24(7), 2571–2580.

    Article  CAS  Google Scholar 

  25. Shaw, S. J.; Tod, D. A. The effects of cure conditions on a rubber-modified epoxy adhesive. J. Adhesion. 1989, 28(4), 231–246.

    Article  CAS  Google Scholar 

  26. Levita, G.; Petris, S. D.; Marchetti, A.; Lazzeri, A. Crosslink density and fracture toughness of epoxy resisn, J. Mater. Sci. 1991, 26(9), 2348–2352.

    Article  CAS  Google Scholar 

  27. Liu, S. H.; Nauman, E. B. Effects of crosslinking density on the toughening mechanisms of rubber-modified thermosets. J. Mater. Sci. 1991, 26(24), 6581–6590.

    Article  CAS  Google Scholar 

  28. Bradley, W. L.; Schultz, W.; Corelto, C.; Komatsu, S. “The synergistic effect of crosslink density and rubber additions on the fracture toughness of polymers, In Toughened Plastics”, ed. by Riew C. K.; Kinloch, A. J., ACS, Washington, 1993, p. 317.

  29. Wang, H. H.; Chen, J. C. Modification and compatibility of epoxy resin with hydroxyl terminated or amine terminated polyuretanes. Polym. Eng. Sci. 1995, 35(18), 1468–1475.

    Article  CAS  Google Scholar 

  30. Kishi, H.; Shi, Y. B.; Huang, J.; Yee, A. F. Shear ductility and toughenability study of highly cross-linked epoxy/ polyethersulphone, J. Mater. Sci. 1998, 32(3), 3479–3488.

    Article  Google Scholar 

  31. Franco, M.; Mondragon, I.; Bucknall, C. B. Blends of epoxy resin with amine-terminated polyoxypropylene elastomer: Morphology and properties. J. Appl. Polym. Sci. 1999, 72(3), 427–434.

    Article  CAS  Google Scholar 

  32. Aizpurua, B.; Franco, M.; Corcuer, M. A.; Riccardi, C. C.; Mondragon, I. Chemorheology and ultimate behavior of epoxy-amine mixtures modified with a liquid oligomer. J. Appl. Polym. Sci. 2000, 76(8), 1269–1279.

    Article  CAS  Google Scholar 

  33. Arias, M. L.; Frontini, P. M.; Williams, R. J. J. Analysis of the damage zone around the crack tip for two rubber-modified epoxy matrices exhibiting different toughenability. Polymer 2003, 44(5), 1537–1546.

    Article  CAS  Google Scholar 

  34. Kang, B. U.; Jho, J. Y.; Kim, J.; Lee, S. S.; Park, Lim. S.; Choe, C. R. Effect of molecular weight between crosslinks on the fracture behavior of rubber-toughened epoxy adhesives. J. Appl. Polym. Sci. 2001, 79(1), 38–48.

    Article  CAS  Google Scholar 

  35. Kishi, H.; Naitou, T.; Matsuda, S.; Murakami, A.; Muraji, Y.; Nakagawa, Y. Mechanical oroperties and inhomogeneous nanostructures of dicyandiamide-cured epoxy resins. J. Polym. Sci., Part B: Polym. Phys. 2007, 45(12), 1425–1434.

    Article  CAS  Google Scholar 

  36. Zhang, D. H.; Jia, D. M.; Huang, X. B. Bisphenol-A epoxy resin reinforced and toughened by hyperbranched epoxy resin. Front. Chem. Eng. China 2007, 1(4), 349–354.

    Article  CAS  Google Scholar 

  37. Mc Aninch, I. M.; Palmese, G. R.; Len hart, J. L.; Scala, J. J. L. Epoxy-amine networks with varying epoxy polydispersity. J. Appl. Polym. Sci. 2015, 132(8), 41503–41512.

    Article  Google Scholar 

  38. Kishi, H.; Kunimitsu, Y.; Nakashima, Y.; Abe, T.; Imade, J.; Oshita, S.; Morishita, Y.; Asada, M. Control of nanostructures generated in epoxy matrices blended with PMMA-b-PnBA-b-PMMA triblock copolymers. Express Polym. Lett. 2015, 9(1), 23–35.

    Article  CAS  Google Scholar 

  39. Acebo, C.; Alorda, M.; Ferrando, F.; Fernández-Francos, X.; Serra, A.; Morancho, J. M.; Salla, J. M.; Ramis X. Epoxy/anhydride thermosets modified with end-capped star polymers with poly(ethyleneimine) cores of different molecular weight and poly(ε-caprolactone) arms. Express Polym. Lett. 2015, 9(9), 809–823.

    Article  CAS  Google Scholar 

  40. Thomas, R.; Abraham, J.; Thomas, S.; Thomas, S. Influence of carboxyl-terminated (butadiene-co-acrylonitrile) loading on the mechanical and thermal properties of cured epoxy blends. J. Polym. Sci., Part B: Polym. Phys. 2004, 42(13), 2531–2544.

    Article  CAS  Google Scholar 

  41. Yang, G.; Fu, S.; Yang, J. P. Preparation and mechanical properties of modified epoxy resins with flexible diamines. Polymer 2007, 48(1), 302–310.

    Article  CAS  Google Scholar 

  42. Yang, G.; Zheng, B.; Yang, J. P.; Xu, G. S.; Fu, S. Y. Preparation and cryogenic mechanical properties of epoxy resins modified by poly(ethersulfone). J. Polym. Sci., Part A: Polym. Chem. 2008, 46(2), 612–624.

    Article  CAS  Google Scholar 

  43. Yang, J. P.; Chen, Z. K.; Yang, G.; Fu, S. Y.; Ye, L. Simultaneous improvements in the cryogenic tensile strength, ductility and impact strength of epoxy resins by a hyperbranched polymer. Polymer 2008, 49(13), 3168–3175.

    Article  CAS  Google Scholar 

  44. Chen, Z. K.; Yang, G.; Yang, J. P.; Fu, S. Y.; Ye, L.; Huang, Y. G. Simultaneously increasing cryogenic strength, ductility and impact resistance of epoxy resins modified by n-butyl glycidyl ether. Polymer 2009, 50(19), 4753–4759.

    Article  CAS  Google Scholar 

  45. Zhao, Y.; Chen, Z. K.; Liu, Y.; Xiao, H. M.; Feng, Q. P.; Fu, S. Y. Simultaneously enhanced cryogenic tensile strength and fracture toughness of epoxy resins by carboxylic nitrilebutadiene nano-rubber. Compos: Part A. 2013, 55, 178–187.

    Article  CAS  Google Scholar 

  46. Liu. Yang, G.; Xiao, H. M.; Feng, Q. P.; Fu, S. Y. Mechanical properties of cryogenic epoxy adhesives: effects of mixed curing agent content. Int. J. Adhes. Adhes. 2013, 41, 113–118.

    Article  Google Scholar 

  47. Feng, Q. P.; Yang, J. P.; Liu, Y. I.; Xiao, H.; Fu, S. Simultaneously enhanced cryogenic tensile strength, ductility and impact resistance of epoxy resins by polyethylene glycol. J. Mater. Sci. Technol.; 2014, 30(1), 90–96.

    Article  CAS  Google Scholar 

  48. Halawani, N.; Augé, J. L.; Morel, H.; Gain, O.; Pruvost, S. Electrical, thermal and mechanical properties of poly-etherimide epoxy-diamine blend. Compos. Part B 2017, 110, 530–541.

    Article  CAS  Google Scholar 

  49. Cheng, X.; Wu, Q.; Morgan, S. E.; Wiggins, J. S. Morphologies and mechanical properties of polyethersulfone modified epoxy blends through multifunctional epoxy composition. J. Appl. Polym. Sci. 2017, 134(18), 44775–44785.

    Article  Google Scholar 

  50. Karger-Kocsis J.; Friedrich K. Fatigue crack propagation and related failure in modified, anhydride-cured epoxy resins. Colloid. Polym. Sci. 1992, 270(6), 549–562.

    Article  CAS  Google Scholar 

  51. Karger-Kocsis J.; Friedrich K. Microstructure-related fracture toughness and fatigue crack growth behavior in toughened, anhydride-cured epoxy resins. Compos. Sci. Technol. 1993, 48(1), 263–272.

    Article  CAS  Google Scholar 

  52. Marks, M. J.; Snelgrove, R. V. Effect of conversion on the structure-property relationships of amine-cured epoxy thermosets. ACS Appl. Mater. Interfaces 2009, 1(4), 921–926.

    Article  CAS  Google Scholar 

  53. Pramanik, M.; Fowler, E. W.; Rawlins, J. W. Another look at epoxy thermosets correlating structure with mechanical properties. Polym. Eng. Sci. 2014, 54(9), 1990–2004.

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Mohammad Hosain Beheshty.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Khalina, M., Beheshty, M.H. & Salimi, A. Preparation and Characterization of DGEBA/EPN Epoxy Blends with Improved Fracture Toughness. Chin J Polym Sci 36, 632–640 (2018). https://doi.org/10.1007/s10118-018-2022-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10118-018-2022-1

Keywords

Navigation