Terahertz Spectroscopy of Polymers

  • Christian Jansen
  • Steffen Wietzke
  • Martin Koch
Part of the Springer Series in Optical Sciences book series (SSOS, volume 171)


Polymers and terahertz (THz) waves form a fruitful symbiosis: on the one hand, non-polar plastics serve as base materials for THz optics as they exhibit low absorption and excellent machinability. On the other hand, THz time-domain spectroscopy (TDS) grants access to unique information about the molecular structure and morphology of polymers, offering an immense portfolio of interesting scientific opportunities. Furthermore, contact-free, non-destructive testing with non-ionizing THz radiation could evolve as a valuable addition to or substitution of ultrasonic and X-ray characterization, especially in quality inspection and process control applications. This chapter aims to give an overview of recent activities in this field, covering both the spectroscopic analysis of polymers with THz waves as well as the non-destructive testing of plastic components with THz systems.


Lattice Mode Orientation Polarization Polymeric Compound Wood Plastic Composite Cyclic Olefin Copolymer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors would like to express their sincere gratitude to each of the generous individuals who have permitted us to display some version of their data and illustrations for this chapter. This includes Frank Rutz (Fraunhofer Institute for Applied Solid-State Physics, Freiburg); Norman Krumbholz, Christian Jördens (Volkswagen AG, Wolfsburg), Markus Lehnhardt, Saranyu Lüders, Dirk Romeike (Institute for High Frequency Technology, TU Braunschweig), Sangam Chatterjee, Marco Reuter, Tilmann Jung, Maik Scheller and Nico Vieweg (Philipps-Universität Marburg). Further thanks are addressed to Prof. Guozhong Zhao (Capital Normal University of China), Thomas Hochrein, Benjamin Baudrit, Eduard Kraus, Dietmar Kraft, Thomas Zentgraf, Neda Kovacevic, Karsten Kretschmer and Martin Bastian (Southern German Plastics Center (Süddeutsches Kunststoff-Zentrum)) for providing plastic samples, additional measurements and helpful advice. The authors thank Wibke Dempwolf, Prof. Henning Menzel (Institute of Technical Chemistry, TU Braunschweig), Judith Hehl, Seema Agarwal, Prof. Andreas Greiner (Philipps-Universität Marburg) and Prof. Stefan Sostmann (ContiTech) and Neda Kovacevic, Benjamin Baudrit (SKZ) for DSC and DMA measurements, respectively. The authors also appreciate the fruitful discussions with Rafal Wilk (Menlo Systems); Ioachim Pupeza (Max Planck Institute of Quantum Optics); Christian Paulik (Borealis Polyolefine GmbH, Linz, Austria); Tomasz Hasek (Dräger), Kai Baaske (PTB), Ibraheem A. Ibraheem (INRS-EMT); Ole Peters, Michael Schwerdtfeger, Bernd Heinen, Matthias Wichmann, Benedikt Scherger, Matthias Stecher, Kristian Altmann and Thorsten Probst (Philipps-Universität Marburg).

The authors thank the Federal Ministry of Education and Research (BMBF) for funding the projects 13N11052, 13N8572, 13N9406, and 13N9466. Furthermore, we are grateful for the support of the Federal Ministry of Economics and Technology (BMWi), grants 182 ZN, 269 ZN, 345 ZN and VP2376001AB9, administered by the German Federation of Industrial Research Associations (AiF). Steffen Wietzke and Christian Jansen like to express their appreciation to the Federal Ministry of Education and Research for funding the preparatory project CHN 10/A11 (fact-finding visit at the Capital Normal University of China) and to the National Natural Science Foundation of China for Grant No. 50971094, both in the framework of the scientific and technological cooperation between China and Germany.


  1. 1.
    PlasticsEurope, Plastics—the Facts 2010: an analysis of European plastics production, demand and recovery for 2009. Technical Report, PlasticsEurope, 2010Google Scholar
  2. 2.
    S. Krimm, Infrared spectra of high polymers. Fortschr. Hochpolym. Fors. 2, 51–172 (1960)CrossRefGoogle Scholar
  3. 3.
    V.A. Bershtein, V.A. Ryzhov, Far infrared spectroscopy of polymers. Adv. Polym. Sci. 114, 42–121 (1994)Google Scholar
  4. 4.
    M. Scheller, M. Koch, Terahertz quasi time domain spectroscopy. Opt. Express 17, 17723–17733 (2009)ADSCrossRefGoogle Scholar
  5. 5.
    Teralyzer Data Extraction Suite, Lytera UG (haftungsbeschränkt),
  6. 6.
    P.Y. Han, M. Tani, M. Usami, S. Kono, R. Kersting, X.-C. Zhang, A direct comparison between terahertz time-domain spectroscopy and far-infrared Fourier transform spectroscopy. J. Appl. Phys. 89, 2357–2359 (2001)ADSCrossRefGoogle Scholar
  7. 7.
    R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, T. Kürner, Properties of building and plastic materials in the THz range. Int. J. Infrared Millim. Waves 28, 363–371 (2007)ADSCrossRefGoogle Scholar
  8. 8.
    N. Nagai, R. Fukasawa, Abnormal dispersion of polymer films in the THz frequency region. Chem. Phys. Lett. 388, 479–482 (2004)ADSCrossRefGoogle Scholar
  9. 9.
    Y.-S. Jin, G.-J. Kim, S.-G. Jeon, Terahertz dielectric properties of polymers. J. Korean Phys. Soc. 49, 513–517 (2006)Google Scholar
  10. 10.
    S. Wietzke, M. Reuter, N. Nestle, E. Klimov, U. Zadok, B. Fischer, M. Koch, Analyzing morphology and thermal history of polybutylene terephthalate by THz time-domain spectroscopy. J. Infrared Millim. Terah. Waves. 32, 952–959 (2011)Google Scholar
  11. 11.
    H. Hoshina, Y. Morisawa, H. Sato, A. Kamiya, I. Noda, Y. Ozaki, C. Otani, Higher order conformation of poly(3-hydroxyalkanoates) studied by terahertz time-domain spectroscopy. Appl. Phys. Lett. 96, 101904 (2010)ADSCrossRefGoogle Scholar
  12. 12.
    J. Balakrishnan, B.M. Fischer, D. Abbott, Sensing the hygroscopicity of polymer and copolymer materials using terahertz time-domain spectroscopy. Appl. Opt. 48, 2262–2266 (2009)ADSCrossRefGoogle Scholar
  13. 13.
    C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg, M. Salhi, N. Krumbholz, C. Jördens, T. Hochrein, M. Koch, Terahertz imaging: applications and perspectives. Appl. Opt. 49, E48–E57 (2010)ADSCrossRefGoogle Scholar
  14. 14.
    D. Turchinovich, A. Kammoun, P. Knobloch, T. Dobbertin, M. Koch, Flexible all-plastic mirrors for the THz range. Appl. Phys. A Mater. Sci. Process. 74, 291–293 (2002)ADSCrossRefGoogle Scholar
  15. 15.
    Y.H. Lo, R. Leonhardt, Aspheric lenses for terahertz imaging. Opt. Express 16, 15991–15998 (2008)ADSCrossRefGoogle Scholar
  16. 16.
    A. Sengupta, A. Bandyopadhyay, B.F. Bowden, J.A. Harrington, J.F. Federici, Characterisation of olefin copolymers using terahertz spectroscopy. Electron. Lett. 42, 1477–1479 (2006)CrossRefGoogle Scholar
  17. 17.
    A. Argyros, M.A. van Eijkelenborg, M.C. Large, I.M. Bassett, Hollow-core microstructured polymer optical fiber. Opt. Lett. 31, 172–174 (2006)ADSCrossRefGoogle Scholar
  18. 18.
    K. Nielsen, H.K. Rasmussen, A.J. Adam, P.C. Planken, O. Bang, P.U. Jepsen, Bendable, low-loss Topas fibers for the terahertz frequency range. Opt. Express 17, 8592–8601 (2009)ADSCrossRefGoogle Scholar
  19. 19.
    B. Fischer, M. Hoffmann, P. U. Jepsen, and M. Walther, Use of the plastic materials topas and zeonex for biotechnological applications in the terahertz range, European Patent Application—EP1505382, 2005Google Scholar
  20. 20.
    J.U.Y. Shin, J.I.Y. Park, C. Liu, J. He, S.C. Kim, Chemical structure and physical properties of cyclic olefin copolymers (IUPAC technical report). Pure Appl. Chem. 77, 801–814 (2005)CrossRefGoogle Scholar
  21. 21.
    B. Wunderlich, Thermodynamics and kinetics of crystallization of flexible molecules. J. Polym. Sci. Part B Polym. Phys. 46, 2647–2659 (2008)ADSCrossRefGoogle Scholar
  22. 22.
    J. Dobbertin, A. Hensel, C. Schick, Dielectric spectroscopy and calorimetry in the glass transition region of semi-crystalline poly(ethylene terephthalate). J. Therm. Anal. Calorim. 47, 1027–1040 (1996)CrossRefGoogle Scholar
  23. 23.
    R.F. Boyer, Transitions and relaxations, in Encyclopedia of Polymer Science and Technology, vol. 2, ed. H.F. Mark (Wiley, New York, 1977), pp. 745–839Google Scholar
  24. 24.
    M. Tasumi, S. Krimm, Crystal vibrations of polyethylene. J. Chem. Phys. 46, 755–766 (1967)ADSCrossRefGoogle Scholar
  25. 25.
    G.D. Dean, D.H. Martin, Inter-molecular vibrations of crystalline polyethylene and long-chain paraffins. Chem. Phys. Lett. 1, 415–416 (1967)ADSCrossRefGoogle Scholar
  26. 26.
    M.I. Bank, S. Krimm, Lattice-frequency studies of crystalline and fold structure in polyethylene. J. Appl. Phys. 39, 4951–4958 (1968)ADSCrossRefGoogle Scholar
  27. 27.
    J.R. Birch, K.F. Ping, Temperature dependence of the FIR optical constants of low density polyethylene. Infrared Phys. Technol. 36, 673–677 (1995)ADSCrossRefGoogle Scholar
  28. 28.
    J.W. Fleming, G.W. Chantry, P.A. Turner, E.A. Nicol, Temperature effects and the observation of the B2u lattice mode in the far infrared absorption spectrum of polyethylene. Chem. Phys. Lett. 17, 84–85 (1972)ADSCrossRefGoogle Scholar
  29. 29.
    J. Birch, E. Nicol, The FIR optical constants of the polymer TPX. Infrared Phys. 24, 573–575 (1984)ADSCrossRefGoogle Scholar
  30. 30.
    G.W. Chantry, H.M. Evans, J.W. Fleming, H.A. Gebbie, TPX, a new material for optical components in the far infra-red spectral region. Infrared Phys. 9, 31–33 (1969)ADSCrossRefGoogle Scholar
  31. 31.
    V.A. Bershtein, V.A. Ryzhov, Relationship between molecular characteristics of polymers and parameters of far-infrared spectra. J. Macromol. Sci. Phys. B 23, 271–287 (1984)CrossRefGoogle Scholar
  32. 32.
    M.J. Hannon, F.J. Boerio, J.L. Koenig, Vibrational analysis of polytetrafluoroethylene. J. Chem. Phys. 50, 2829–2836 (1969)ADSCrossRefGoogle Scholar
  33. 33.
    G.W. Chantry, J.W. Fleming, E.A. Nicol, H.A. Willis, M.E.A. Cudby, F.J. Boerio, Far infra-red spectrum of crystalline polytetrafluoroethylene. Polymer 15, 69–73 (1974)CrossRefGoogle Scholar
  34. 34.
    G.W. Chantry, E.A. Nicol, R.G. Jones, H.A. Willis, M.E.A. Cudby, On the vibrational assignment problem for polytetrafluoroethylene: 1. The far infra-red spectrum, Polymer 18, 37–41 (1977)Google Scholar
  35. 35.
    M. Kobayashi, K. Tashiro, H. Tadokoro, Molecular vibrations of three crystal forms of poly(vinylidene fluoride). Macromolecules 8, 158–171 (1975)ADSCrossRefGoogle Scholar
  36. 36.
    J.F. Rabolt, K.W. Johnson, Low frequency vibrations in polyvinylidene fluoride (form II). J. Chem. Phys. 59, 3710–3712 (1973)ADSCrossRefGoogle Scholar
  37. 37.
    M. Latour, R.L. Moreira, Submillimeter infrared absorption and chain conformations of poly(vinylidene fluoride) and copolymers. II. Phase transition analysis. J. Polym. Sci. Part B Polym. Phys. 25, 1717–1723 (1987), cited By (since 1996): 3Google Scholar
  38. 38.
    H. Tadokoro, Structure of Crystalline Polymers (Robert E. Krieger Publishing Company, Malabar, Florida, 1990)Google Scholar
  39. 39.
    W.F.X. Frank, H. Fiedler, On the problem of direct observation of H-bridge interactions in polymers by FIR spectroscopy. Infrared Phys. 19, 481–489 (1979), cited By (since 1996): 1Google Scholar
  40. 40.
    C.S. Nie, F. Kremer, A. Poglitsch, G. Bechtold, L. Genzel, Picosecond relaxations in hydrated polyamide-6 observed by millimeter-wave spectroscopy. J. Polym. Sci. Part A-2 Polym. Phys. 23, 1247–1254 (1985)Google Scholar
  41. 41.
    H. Tadokoro, M. Kobayashi, H. Yoshidome, T.A.I. Kazuo, D. Marino, Structural studies of polyesters. II. Far-infrared spectra of aliphatic polyesters: comparison with alpha-polyamides. J. Chem. Phys. 49, 3359–3373 (1968)ADSCrossRefGoogle Scholar
  42. 42.
    M. Goldstein, D. Stephenson, W.F. Maddams, Far infra-red spectrum of poly(vinyl chloride). Polymer 24, 823–826 (1983)CrossRefGoogle Scholar
  43. 43.
    J.M.G. Cowie, Polymers: Chemistry and Physics of Modern Materials, 3rd edn. (Taylor and Francis, Boca Raton, 2008)Google Scholar
  44. 44.
    W. Frank, U. Leute, Infrared and Millimeter Waves: Electromagnetic Waves in Matter, vol. 8, Chap. 2 (Academic, New York, 1983)Google Scholar
  45. 45.
    R.B. Beevers, Polymer characterization by refractometry. J. Polym. Sci. Polym. Phys. Ed. 12, 1407–1415 (1974)ADSCrossRefGoogle Scholar
  46. 46.
    G. Chantry, Infrared and Millimeter Waves: Electromagnetic Waves in Matter (Academic, New York, 1983)Google Scholar
  47. 47.
    K. Tashiro, M. Kobayashi, Structural phase transition in ferroelectric fluorine polymers: X-ray diffraction and infrared/Raman spectroscopic study. Phase Transition 18, 213–246 (1989)CrossRefGoogle Scholar
  48. 48.
    R. Hasegawa, M. Kobayashi, H. Tadokoro, Molecular conformation and packing of poly(vinylidene fluoride). Stability of three crystalline forms and the effect of high pressure. Polym. J. 3, 591–599 (1972)CrossRefGoogle Scholar
  49. 49.
    A. Warrier, S. Krimm, Intermolecular interactions in crystalline poly(vinyl chloride). Macromolecules 3, 709–710 (1970)ADSCrossRefGoogle Scholar
  50. 50.
    R.J. Fredericks, T.H. Doyne, R.S. Sprague, Crystallographic studies of nylon 4. I. Determination of the crystal structure of the alpha polymorph of nylon 4. J. Polym. Sci. Part A-2 Polym. Phys. 4, 899–911 (1966)ADSCrossRefGoogle Scholar
  51. 51.
    R.H. Boyd, Relaxation processes in crystalline polymers: molecular interpretation—a review. Polymer 26, 1123–1133 (1985)CrossRefGoogle Scholar
  52. 52.
    J.A. Forrest, K. Dalnoki-Veress, J.R. Stevens, J.R. Dutcher, Effect of free surfaces on the glass transition temperature of thin polymer films. Phys. Rev. Lett. 77, 2002–2005 (1996)ADSCrossRefGoogle Scholar
  53. 53.
    B. Wunderlich, Reversible crystallization and the rigid-amorphous phase in semicrystalline macromolecules. Prog. Polym. Sci. 28, 383–450 (2003)CrossRefGoogle Scholar
  54. 54.
    J.H. Gibbs, E.A. DiMarzio, Nature of the glass transition and the glassy state. J. Chem. Phys. 28, 373–383 (1958), cited By (since 1996): 531Google Scholar
  55. 55.
    J.D. Menczel, R.B. Primeeds, Thermal Analysis of Polymers: Fundamentals and Applications (Wiley, Hoboken, 2009)Google Scholar
  56. 56.
    G. Patterson, Physical Chemistry of Macromolecules, 2nd edn. (Taylor and Francis, Boca Raton, 2007)Google Scholar
  57. 57.
    K. Nakagawa, Y. Ishida, Dielectric relaxations and molecular motions in poly(vinylidene fluoride) with crystal form II. J. Polym. Sci. Polym. Phys. Ed. 11, 1503–1533 (1973)ADSGoogle Scholar
  58. 58.
    R. Simha, R.F. Boyer, On a general relation involving the glass temperature and coefficients of expansion of polymers. J. Chem. Phys. 37, 1003–1007 (1962)ADSCrossRefGoogle Scholar
  59. 59.
    S. Wietzke, C. Jansen, T. Jung, M. Reuter, B. Baudrit, M. Bastian, S. Chatterjee, M. Koch, Terahertz time-domain spectroscopy as a tool to monitor the glass transition in polymers. Opt. Express 17, 19006–19014 (2009)ADSCrossRefGoogle Scholar
  60. 60.
    S. Wietzke, C. Jansen, M. Reuter, T. Jung, D. Kraft, S. Chatterjee, B.M. Fischer, M. Koch, Terahertz spectroscopy on polymers: a review of morphological studies. J. Mol. Struct. 1006(1–3), 41–51 (2011). doi:  10.1016/j.molstruc.2011.07.036, Google Scholar
  61. 61.
    S. Wietzke, C. Jansen, M. Reuter, T. Jung, J. Hehl, D. Kraft, S. Chatterjee, A. Greiner, M. Koch, Thermomorphological study of the terahertz lattice modes in polyvinylidene fluoride and high-density polyethylene. Appl. Phys. Lett. 97, 022901 (2010)ADSCrossRefGoogle Scholar
  62. 62.
    R. Androsch, M.L. Di Lorenzo, C. Schick, B. Wunderlich, Mesophases in polyethylene, polypropylene, and poly(1-butene). Polymer 51, 4639–4662 (2010)CrossRefGoogle Scholar
  63. 63.
    J. Murphy, Additives for Plastics Handbook (Elsevier, Oxford, 2001)Google Scholar
  64. 64.
    D.B. Todded, Plastics Compounding: Equipment and Processing (Hanser, Munich, 1998)Google Scholar
  65. 65.
    N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, M. Koch, Monitoring polymeric compounding processes inline with THz time-domain spectroscopy. Polym. Test. 28, 30–35 (2009)CrossRefGoogle Scholar
  66. 66.
    N. Krumbholz, T. Hochrein, N. Vieweg, I. Radovanovic, I. Pupeza, M. Schubert, K. Kretschmer, M. Koch, Degree of dispersion of polymeric compounds determined with terahertz time-domain spectroscopy. Polym. Eng. Sci. 51, 109–116 (2011)CrossRefGoogle Scholar
  67. 67.
    C. Jansen, S. Wietzke, V. Astley, D.M. Mittleman, M. Koch, Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies. Appl. Phys. Lett. 96, 111108 (2010)ADSCrossRefGoogle Scholar
  68. 68.
    C. Jansen, C. Jördens, M. Koch, Terahertz-Volumen-Bauelement, German Patent Application, 2008Google Scholar
  69. 69.
    R. Boulay, P. Dube, P.A. Belanger, T. Vu-Khanh, P. Cielo, Analysis of filler concentrations and orientation in reinforced polymers by far-IR techniques. SPIE 665, 352–360 (1986)CrossRefGoogle Scholar
  70. 70.
    S. Wietzke, C. Jansen, F. Rutz, D.M. Mittleman, M. Koch, Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy. Polym. Test. 26, 614–618 (2007)CrossRefGoogle Scholar
  71. 71.
    M. Scheller, S. Wietzke, C. Jansen, M. Koch, Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory. J. Phys. D Appl. Phys. 42, 065415 (2009)ADSCrossRefGoogle Scholar
  72. 72.
    M. Scheller, C. Jansen, M. Koch, Analyzing sub-100-\(\mu \)m samples with transmission terahertz time domain spectroscopy. Opt. Commun. 282, 1304–1306 (2009)ADSCrossRefGoogle Scholar
  73. 73.
    G. Blom, Probability and Statistics: Theory and Applications (Springer, Berlin, 1989)zbMATHGoogle Scholar
  74. 74.
    R. Kacker, A. Jones, On use of Bayesian statistics to make the guide to the expression of uncertainty in measurement consistent. Metrologia 40, 235–248 (2003)ADSCrossRefGoogle Scholar
  75. 75.
    B.N. Taylor, C.E. Kuyatt, Guidelines for evaluating and expressing the uncertainty of NIST measurement results. NIST Technical Note 1297, 1994 edn. (U.S. Govt. Printing Office, Washington, DC, 1994)Google Scholar
  76. 76.
    L. K. H. van Beek, Progress in Dielectrics (Tliffe, London, 1969), Vol. 7, chap. Dielectric behaviour of heterogeneous systems, pp. 69–114.Google Scholar
  77. 77.
    D.K. Hale, The physical properties of composite materials. J. Mater. Sci. 11, 2105–2141 (1976)ADSCrossRefGoogle Scholar
  78. 78.
    J.C. Maxwell-Garnett, Colours in metal glasses and in metallic films. Philos. Trans. R. Soc. London, Ser. A 203, 385–420 (1904)ADSCrossRefGoogle Scholar
  79. 79.
    D.A.G. Bruggeman, Berechnung verschiedener physikalischer Konstanten von heterogenen Substanzen: I Dielektrizitätskonstanten und Leitfähigkeiten der Mischkörper aus isotropen Substanzen. Ann. Phys. 24, 636–664 (1935)CrossRefGoogle Scholar
  80. 80.
    D. Polder, J.H. van Santen, The effective permeability of mixtures of solids. Physica 12, 257–271 (1946)ADSCrossRefGoogle Scholar
  81. 81.
    W. Grellmann, S. Seidler, Polymer Testing (Hanser, Munich, 2007)CrossRefGoogle Scholar
  82. 82.
    M. Bastian, K. Kretschmer, M. Schubert, A new online measurement technique for the evaluation of the degree of dispersion, in Proceedings of the 21st Annual Meeting of the Polymer Processing Society (PPS21), 2005Google Scholar
  83. 83.
    D.R. França, C.-K. Jen, K.T. Nguyen, R. Gendron, Ultrasonic in-line monitoring of polymer extrusion. Polym. Eng. Sci. 40, 82–94 (2000)CrossRefGoogle Scholar
  84. 84.
    M. Stephan, S. Große, M. Stintz, U. Blankschein, Real time detection of particulate heterogeneities in polymer extrusion processes using microphotometric measuring method. Plast. Rubber Compos. 35, 432–438 (2006)CrossRefGoogle Scholar
  85. 85.
    M. Stephan, S. Große, M. Stintz, U. Blankschein, Microphotometric inline determination of polymer blend morphologies during extrusion processing. J. Appl. Polym. Sci. 103, 258–262 (2007)CrossRefGoogle Scholar
  86. 86.
    M. Xanthos, A. Patel, Recent developments in in-line spectroscopy/microscopy for monitoring extrusion processes. Adv. Polym. Technol. 14, 151–157 (1995)CrossRefGoogle Scholar
  87. 87.
    D. Fischer, T. Bayer, K.-J. Eichhorn, M. Otto, In-line process monitoring on polymer melts by NIR-spectroscopy. Fresenius J. Anal. Chem. 359, 74–77 (1997)CrossRefGoogle Scholar
  88. 88.
    N. Vieweg, N. Krumbholz, T. Hasek, R. Wilk, V. Bartels, C. Keseberg, V. Pethukhov, M. Mikulics, L. Wetenkamp, M. Koch, Fiber-coupled THz spectroscopy for monitoring polymeric compounding processes. Proc. SPIE 6616, 66163M (2007)ADSCrossRefGoogle Scholar
  89. 89.
    T. Hochrein, N. Krumbholz, K. Kretschmer, M. Bastian, M. Koch, Terahertz-spectroscopy: a new tool for monitoring compounding processes, in Proceedings of the 24th Annual Meeting of the Polymer Processing Society (PPS24), 2008 (Accepted as invited keynote)Google Scholar
  90. 90.
    J.T. Kindt, C.A. Schmuttenmaer, Far-infrared dielectric properties of polar liquids probed by femtosecond terahertz pulse spectroscopy. J. Phys. Chem. 100, 10373–10379 (1996)CrossRefGoogle Scholar
  91. 91.
    R. Boulay, B. Drouin, R. Gagnon, P.A. Belanger, P. Cielo, Far infra-red moisture monitoring in polymeric composites. Polym. Commun. (Guildford) 26, 69–71 (1985)Google Scholar
  92. 92.
    H. Looyenga, Dielectric constants of heterogeneous mixtures. Physica 31, 401–406 (1965)ADSCrossRefGoogle Scholar
  93. 93.
    C. Jördens, Einsatz und Optimierung von Terahertz-Systemen in der zerstörungsfreien Messtechnik. Ph.D. Thesis, Technische Universität Carolo-Wilhelmina zu Braunschweig, 2009Google Scholar
  94. 94.
    D. Zimdars, J. White, G. Sucha, G. Fichter, G. Stuk, C. Megdanoff, A. Chernovsky, S.L. Williamson, Terahertz measurement and imaging detection of delamination and water intrusion in ground based radome panels. Proc. SPIE (The International Society for Optical Engineering) 6549, 654906 (2007)Google Scholar
  95. 95.
    D.A. Grewell, A. Benatar, J.B. Park, Plastics and composites welding handbook (Hanser, Munich, 2003)Google Scholar
  96. 96.
    S. Wietzke, C. Jördens, N. Krumbholz, B. Baudrit, M. Bastian, M. Koch, Terahertz imaging: a new non-destructive technique for the quality control of plastic weld joints. J. Eur. Opt. Soc. (Rapid Publications) 2, 07013 (2007)CrossRefGoogle Scholar
  97. 97.
    S. Wietzke, E. Kraus, B. Baudrit, P. Heidemeyer, O. Peters, N. Krumbholz, M. Koch, M. Bastian, Zerstörungsfreie Terahertzprüfung von stoffschlüssigen Kunststoffverbindungen. Technical Report, Süddeutsches Kunststoff-Zentrum, Würzburg, 2010Google Scholar
  98. 98.
    J. Lagarias, J. Reeds, M. Wright, P. Wright, Convergence properties of the Nelder–Mead simplex algorithm in low dimensions. SIAM J. Optim. 9, 112–147 (1998)Google Scholar
  99. 99.
    C. Jansen, S. Wietzke, H. Wang, M. Koch, G. Zhao, Terahertz spectroscopy on adhesive bonds. Polym. Test. 30, 150–154 (2010)CrossRefGoogle Scholar
  100. 100.
    M. Born, E. Wolf, Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light, 7th edn. (Cambridge University Press, Cambridge, 1999)Google Scholar
  101. 101.
    R. Balkova, S. Holcnerova, V. Cech, Testing of adhesives for bonding of polymer composites. Int. J. Adhes. Adhes. 22, 291–295 (2002)CrossRefGoogle Scholar
  102. 102.
    M.P. Zanni-Deffarges, M.E.R. Shanahan, Diffusion of water into an epoxy adhesive: comparison between bulk behaviour and adhesive joints. Int. J. Adhes. Adhes. 15, 137–142 (1995)CrossRefGoogle Scholar
  103. 103.
    N.C.J. Van der Valk, W.A.M. Van der Marel, P.C.M. Planken, Terahertz polarization imaging. Opt. Lett. 30, 2802–2804 (2005)ADSCrossRefGoogle Scholar
  104. 104.
    C. Jördens, M. Scheller, S. Wietzke, D. Romeike, C. Jansen, T. Zentgraf, K. Wiesauer, V. Reisecker, M. Koch, Terahertz spectroscopy to study the orientation of glass fibres in reinforced plastics. Comp. Sci. Technol. 70, 472–477 (2010)CrossRefGoogle Scholar
  105. 105.
    N. Karpowicz, D. Dawes, M.J. Perry, X.-C. Zhang, Fire damage on carbon fiber materials characterized by THz waves. Proc. SPIE 6212, 62120G (2006)Google Scholar
  106. 106.
    S. Akhtar, A.I. Isayev, Self-reinforced composites of two thermotropic liquid crystalline polymers. Polym. Eng. Sci. 33, 32–42 (1993)CrossRefGoogle Scholar
  107. 107.
    F. Rutz, T. Hasek, M. Koch, H. Richter, U. Ewert, Terahertz birefringence of liquid crystal polymers. Appl. Phys. Lett. 89, 221911 (2006)Google Scholar
  108. 108.
    M. Latour, R.L. Moreira, Submillimeter infrared absorption and chain conformations of poly(vinylidene fluoride) and copolymers. I. Crystalline and amorphous contributions. J. Polym. Sci. Part B Polym. Phys. 25, 1913–1921 (1987)ADSCrossRefGoogle Scholar
  109. 109.
    D.Y. Shen, S.K. Pollack, S.L. Hsu, Far-infrared study of hydrogen bonding in a semicrystalline polyurethane. Macromolecules 22, 2564–2569 (1989)ADSCrossRefGoogle Scholar
  110. 110.
    A. Boldizar, S. Jacobsson, S. Hard, Far infrared birefringence versus other orientational measurements of high-pressure injection-molded high-density polyethylene. J. Appl. Polym. Sci. 36, 1567–1581 (1988)CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Christian Jansen
    • 1
  • Steffen Wietzke
    • 1
  • Martin Koch
    • 1
  1. 1.Fachbereich Physik, AG Terahertz-SystemtechnikPhilipps-Universität MarburgMarburgGermany

Personalised recommendations