Journal of Thermal Analysis and Calorimetry

, Volume 116, Issue 3, pp 1273–1278 | Cite as

Thermal characterization of poly-l-lactide by dielectric analysis and modulated DSC

  • C. A. Gracia-Fernández
  • S. Gómez-Barreiro
  • A. Álvarez-García
  • J. López-BeceiroEmail author
  • B. Álvarez-García
  • S. Zaragoza-Fernández
  • R. Artiaga


Dielectric analysis (DEA) is a very sensitive technique, which allows for detection of small structural changes at the low scale. An advantage of DEA, with respect to other modulated techniques, is the possibility of using a wider frequency range. Molecular relaxations of the order of only a few nanometers are not observed by any other thermoanalytic method. Nevertheless, these small relaxations involve dipole changes that can be observed by DEA. Thus, this technique is used here, in combination with temperature-modulated differential scanning calorimetry (TMDSC) to obtain insightful information about the thermal transitions of poly-l-lactic acid (PLLA), one of the stereo-isomers of polylactide. Its complex thermal behavior is the subject of ongoing debate, with several overlapping crystallization and melting processes. The combined use of TMDSC and DEA provides a better insight of three important transitions of this polymer: the alpha relaxation, the enthalpic relaxation, and the cold crystallization. The dependences of the enthalpy relaxation on the dynamic glass transition relaxation and on the glass transition as a thermal event are evaluated. On the other hand, it will be shown how the cold crystallization can be identified by TMDSC, and DEA helps us understand the effect of crystallization on the dipole movements. The shape of the dielectric permittivity curve at low frequencies is compared to that of the reversing heat capacity to check whether both signals are sensitive or not to the same events. It is also verified how the experimental results of alpha relaxation of PLLA follow an Arrhenius or a Vogel trend.


Poly-l-lactic acid DEA TMDSC Glass transition Enthalpic relaxation Crystallization 



This research has been partially supported by the Spanish Ministry of Science and Innovation, Grant MTM2011-22392 (ERDF included).

Supplementary material

10973_2013_3629_MOESM1_ESM.xls (478 kb)
Supplementary material 1 (XLS 477 kb)


  1. 1.
    McCrum NG, Read ME, Williams G. Anelastic and dielectric effects in polymeric solids. New York: Wiley; 1967.Google Scholar
  2. 2.
    Coln MCW, Senturia SD. The application of linear system theory to parametric microsensor. In: Proceedings of Transducers’ 85. 1985. p. 118–21.Google Scholar
  3. 3.
    Prime RB. Thermosets. In: Turi EA, editor. Thermal characteristics of polymer materials. 2nd ed. San Diego: Academic Press; 1997. p. 1518–23.Google Scholar
  4. 4.
    Hunt BJ, James MI. Polymer characterisation. 1st ed. London: Blackie Academic & Professional; 1993.CrossRefGoogle Scholar
  5. 5.
    Sheppard NF, Senturia SD. Dielectric properties of bisphenol-a epoxy resins. J Polym Sci Part B Polym Phys. 1989;27:753–62.CrossRefGoogle Scholar
  6. 6.
    Senturia SD, Sheppard NF. Dielectric analysis of thermoset cure. In: Dušek K, editor. Epoxy Resins Compos. IV ed. Berlin: Springer; 1986. p. 1–47.CrossRefGoogle Scholar
  7. 7.
    Debye P. Polar molecules. New York: Chemical Catalog Co.; 1929.Google Scholar
  8. 8.
    Cole KS, Cole RH. Dispersion and absorption in dielectrics I. Alternating current characteristics. J Chem Phys. 1941;9:341–51.CrossRefGoogle Scholar
  9. 9.
    Davidson DW, Cole RH. Dielectric relaxation in glycerol, propylene glycol, and n-propanol. J Chem Phys. 1951;19:1484–90.CrossRefGoogle Scholar
  10. 10.
    Havriliak S, Negami S. A complex plane analysis of α-dispersions in some polymer systems. J Polym Sci Part C Polym Symp. 2007;14:99–117.CrossRefGoogle Scholar
  11. 11.
    Havriliak S, Negami S. A complex plane representation of dielectric and mechanical relaxation processes in some polymers. Polymer. 1967;8:161–210.CrossRefGoogle Scholar
  12. 12.
    Atkinson JL, Vyazovkin S. Dynamic mechanical analysis and hydrolytic degradation behavior of linear and branched poly(l-lactide)s and poly(l-lactide-co-glycolide)s. Macromol Chem Phys. 2013;214:835–43.CrossRefGoogle Scholar
  13. 13.
    Malmgren T, Mays J, Pyda M. Characterization of poly(lactic acid) by size exclusion chromatography, differential refractometry, light scattering and thermal analysis. J Therm Anal Calorim. 2006;83:35–40.CrossRefGoogle Scholar
  14. 14.
    Atkinson JL, Vyazovkin S. Thermal properties and degradation behavior of linear and branched poly(l-lactide)s and poly(l-lactide-co-glycolide)s. Macromol Chem Phys. 2012;213:924–36.CrossRefGoogle Scholar
  15. 15.
    Monticelli O, Bocchini S, Gardella L, Cavallo D, Cebe P, Germelli G. Impact of synthetic talc on PLLA electrospun fibers. Eur Polym J. 2013;49:2572–83.CrossRefGoogle Scholar
  16. 16.
    Zhou Z. Influence of thermal treatment on the thermal behavior of poly-l-lactide. J Macromol Sci Part B. 2007;46:1247–54.CrossRefGoogle Scholar
  17. 17.
    Martinelli A, Calì M, D’Ilario L, Francolini I, Piozzi A. Effect of the nucleation mechanism on complex poly(l-lactide) nonisothermal crystallization process. Part 1: thermal and structural characterization. J Appl Polym Sci. 2011;121:3368–76.CrossRefGoogle Scholar
  18. 18.
    Pyda M, Wunderlich B. Reversing and nonreversing heat capacity of poly(lactic acid) in the glass transition region by TMDSC. Macromolecules. 2005;38:10472–9.CrossRefGoogle Scholar
  19. 19.
    Gracia-Fernández CA, Gómez-Barreiro S, López-Beceiro J, Naya S, Artiaga R. New approach to the double melting peak of poly(l-lactic acid) observed by DSC. J Mater Res. 2012;27:1379–82.CrossRefGoogle Scholar
  20. 20.
    Sasaki T, Yamauchi N, Irie S, Sakurai K. || Differential scanning calorimetry study on thermal behaviors of freeze-dried poly(l-lactide) from dilute solutions. J Polym Sci Part B. 2005;43:115–24.CrossRefGoogle Scholar
  21. 21.
    Pluta M, Jeszka JK, Boiteux G. Polylactide/montmorillonite nanocomposites: structure, dielectric, viscoelastic and thermal properties. Eur Polym J. 2007;43:2819–35.CrossRefGoogle Scholar
  22. 22.
    Sabater i Serra R, Escobar Ivirico JL, Meseguer Dueñas JM, Balado AA, Gómez Ribelles JL, Salmerón Sánchez M. Segmental dynamics in poly(ε-caprolactone)/poly(l-lactide) copolymer networks. J Polym Sci Part B Polym Phys. 2009;47:183–93.CrossRefGoogle Scholar
  23. 23.
    Arnoult M, Dargent E, Mano JF. Mobile amorphous phase fragility in semi-crystalline polymers: comparison of PET and PLLA. Polymer. 2007;48:1012–9.CrossRefGoogle Scholar
  24. 24.
    Magoń A, Pyda M. Study of crystalline and amorphous phases of biodegradable poly(lactic acid) by advanced thermal analysis. Polymer. 2009;50:3967–73.CrossRefGoogle Scholar
  25. 25.
    Pan P, Zhu B, Inoue Y. Enthalpy relaxation and embrittlement of poly(l-lactide) during physical aging. Macromolecules. 2007;40:9664–71.CrossRefGoogle Scholar
  26. 26.
    Vogel H. The law of the relation between the viscosity of liquids and the temperature. Phys Z. 1921;22:645.Google Scholar
  27. 27.
    Kortaberria G, Marieta C, Jimeno A, Arruti P, Mondragon I. Crystallization of poly(l-lactid acid) monitored by dielectric relaxation spectroscopy and atomic force microscopy. J Microsc. 2006;224:277–89.CrossRefGoogle Scholar
  28. 28.
    Núñez-Regueira L, Gracia-Fernndez CA, Gómez-Barreiro S. Characterization of a thermoset by thermal analysis techniques: criterion to assign the value of the α-transition temperature by dielectric analysis. J Appl Polym Sci. 2005;96:2027–37.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2014

Authors and Affiliations

  • C. A. Gracia-Fernández
    • 1
  • S. Gómez-Barreiro
    • 2
  • A. Álvarez-García
    • 3
  • J. López-Beceiro
    • 3
    Email author
  • B. Álvarez-García
    • 3
  • S. Zaragoza-Fernández
    • 3
  • R. Artiaga
    • 3
  1. 1.TA Instruments-Waters CromatografíaAlcobendasSpain
  2. 2.Department of Applied Physics, CESUGAUniversity College of DublinA CoruñaSpain
  3. 3.University of A CoruñaFerrolSpain

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