Journal of Materials Science

, Volume 32, Issue 18, pp 4749–4758 | Cite as

Fracture mechanisms of poly(ethylene terephthalate) and blends with styrene-butadiene-styrene elastomers

  • V Tanrattanakul
  • W. G Perkins
  • F. L Massey
  • A Moet
  • A Hiltner
  • E Baer


Poly(ethylene terephthalate) (PET) was blended with 5 wt % of an elastomeric block copolymer. The hydrogenated styrene-butadiene-styrene (SEBS) elastomers were functionalized with 0–4.5 wt % maleic anhydride grafted on the midblock. Notched tensile tests in the temperature range − 40–55 °C differentiated among the blends in terms of their toughness. The least effective elastomer was the unfunctionalized SEBS; all the functionalized SEBS elastomers effectively increased the toughness of PET. Fractographic analysis indicated that PET and the blend with unfunctionalized SEBS fractured through a pre-existing craze. Although adhesion of the unfunctionalized SEBS to the matrix was poor, the elastomer strengthened the craze somewhat, as indicated by an increase in length of the pre-existing craze when final separation occurred. A functionalized SEBS caused the fracture mechanism to change from crazing to ductile yielding. Graft copolymer formed by reaction of PET hydroxyl end groups with the anhydride in situ was thought to act as an emulsifier to decrease particle size and improve adhesion. These factors promoted cavitation, which relieved the triaxiality at the notch root and permitted the matrix to shear yield.


Fracture Surface Cavitation Crack Path Maleic Anhydride Notch Root 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    V. TANRATTANAKUL, W. G. PERKINS, F. L. MASSEY, A. MOET, A. HILTNER and E. BAER, Polymer (in press).Google Scholar
  2. 2.
    idem, ibid. (in press).Google Scholar
  3. 3.
    I. WALKER and A. A. COLLYER, in “Rubber toughened engineering plastics”, edited by A. A. Collyer (Chapman & Hall, London, 1994) p. 29.CrossRefGoogle Scholar
  4. 4.
    C. CHENG, A. HILTNER, E. BAER, P. R. SOSKEY and S. G. MYLONAKIS, J. Appl. Polym. Sci. 52 (1994) 177.CrossRefGoogle Scholar
  5. 5.
    idem, J. Mater. Sci. 30 (1995) 587.CrossRefGoogle Scholar
  6. 6.
    D. L. WILFONG, A. HILTNER and E. BAER, ibid. 21 (1986) 2014.CrossRefGoogle Scholar
  7. 7.
    M.-P. LEE, A. HILTNER and E. BAER, Polym. Engng. Sci. 32 (1992) 909.CrossRefGoogle Scholar
  8. 8.
    D. DOMPAS, G. GROENINCKX, M. ISOGAWA, T. HASEGAWA and M. KADOKURA, Polymer 35 (1994) 4750.CrossRefGoogle Scholar
  9. 9.
    E. S. SHIN, A. HILTNER and E. BAER, J. Appl. Polym. Sci. 46 (1992) 213.CrossRefGoogle Scholar
  10. 10.
    J. MURRAY and D. HULL, J. Polym. Sci. A-2 8 (1970) 583.CrossRefGoogle Scholar
  11. 11.
    M. J. DOYLE, J. Mater. Sci. 17 (1982) 204.CrossRefGoogle Scholar
  12. 12.
    W. DÖLL, in “Fractography and failure mechanics of polymers and composites”, edited by A. C. Roulin-Moloney (Elsevier Applied Science, London, 1989) p. 387.Google Scholar
  13. 13.
    C. CHENG, N. PEDUTO, A. HILTNER, E. BAER, P. R. SOSKEY and S. G. MYLONAKIS, J. Appl. Polym. Sci. 53 (1994) 513.CrossRefGoogle Scholar
  14. 14.
    C. J. CHOU, K. VIJAYAN, D. KIRBY, A. HILTNER and E. BAER, J. Mater. Sci. 23 (1988) 2533.CrossRefGoogle Scholar
  15. 15.
    H.-J. SUE and A. F. YEE, ibid. 24 (1989) 1447.CrossRefGoogle Scholar
  16. 16.
    M. C. M. van der SANDEN and H. E. MEIJER, Polymer 35 (1994) 2774.CrossRefGoogle Scholar
  17. 17.
    K. DIJKSTRA, J. ter LAAK and R. J. GAYMANS, ibid. 35 (1994) 315.CrossRefGoogle Scholar

Copyright information

© Chapman and Hall 1997

Authors and Affiliations

  • V Tanrattanakul
    • 1
  • W. G Perkins
    • 2
  • F. L Massey
    • 2
  • A Moet
    • 3
  • A Hiltner
  • E Baer
  1. 1.Department of Macromolecular Science and Centre for Applied Polymer ResearchCase Western Reserve UniversityClevelandUSA
  2. 2.Polyester Technical CentreShell Chemical CompanyAkronUSA
  3. 3.Department of Chemical and Petroleum EngineeringUnited Arab Emirate UniversityUnited Arab Emirates

Personalised recommendations