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High thermal conductivity of chain-oriented amorphous polythiophene

A Corrigendum to this article was published on 03 July 2014

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Abstract

Polymers are usually considered thermal insulators, because the amorphous arrangement of the molecular chains reduces the mean free path of heat-conducting phonons. The most common method to increase thermal conductivity is to draw polymeric fibres, which increases chain alignment and crystallinity, but creates a material that currently has limited thermal applications. Here we show that pure polythiophene nanofibres can have a thermal conductivity up to 4.4 W m–1 K–1 (more than 20 times higher than the bulk polymer value) while remaining amorphous. This enhancement results from significant molecular chain orientation along the fibre axis that is obtained during electropolymerization using nanoscale templates. Thermal conductivity data suggest that, unlike in drawn crystalline fibres, in our fibres the dominant phonon-scattering process at room temperature is still related to structural disorder. Using vertically aligned arrays of nanofibres, we demonstrate effective heat transfer at critical contacts in electronic devices operating under high-power conditions at 200 °C over numerous cycles.

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Figure 1: Microstructure of polythiophene nanofibres.
Figure 2: Thermal conductivity measurements of single fibres and vertically aligned arrays.
Figure 3: Application of vertically aligned polythiophene nanofibres as a TIM.
Figure 4: Device demonstration of polythiophene-nanofibre TIM at high temperature.

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  • 17 June 2014

    In the version of this Article originally published, in the section 'Thermal conductivity of individual fibres', the second sentence should have read "The measured thermal conductivity of the several nanofibre samples increases with decreasing diameter..." This error has now been corrected in the online versions of the Article.

References

  1. Choy, C. L. Thermal conductivity of polymers. Polymer 18, 984–1004 (1977).

    Article  CAS  Google Scholar 

  2. Henry, A. Thermal transport in polymers. Ann. Rev. Heat Transfer http://dx.doi.org/10.1615/AnnualRevHeatTransfer.2013006949 (2013).

  3. Han, Z. D. & Fina, A. Thermal conductivity of carbon nanotubes and their polymer nanocomposites: a review. Prog. Polym. Sci. 36, 914–944 (2011).

    Article  CAS  Google Scholar 

  4. Wang, X., Ho, V., Segalman, R. A. & Cahill, D. G. Thermal conductivity of high-modulus polymer fibers. Macromolecules 46, 4937–4943 (2013).

    Article  CAS  Google Scholar 

  5. Liu, J. & Yang, R. Length-dependent thermal conductivity of single extended polymer chains. Phys. Rev. B 86, 104307 (2012).

    Article  Google Scholar 

  6. Arkadii, A., Michael, B., Oleg, G. & Eyal, Z. Effect of supramolecular structure on polymer nanofibre elasticity. Nature Nanotech. 2, 59–62 (2007).

    Article  Google Scholar 

  7. Choy, C. L., Wong, Y. W., Yang, G. W. & Kanamoto, T. Elastic modulus and thermal conductivity of ultradrawn polyethylene. J. Polym. Sci. 37, 3359–3367 (1999).

    Article  CAS  Google Scholar 

  8. Lim, C., Tan, E. & Ng, S. Effects of crystalline morphology on the tensile properties of electrospun polymer nanofibers. Appl. Phys. Lett. 92, 141908 (2008).

    Article  Google Scholar 

  9. Choy, C. L., Chen, F. C. & Luk, W. H. Thermal conductivity of oriented crystalline polymers. J. Polym. Sci. 18, 1187–1207 (1980).

    CAS  Google Scholar 

  10. Papkov, D. et al. Simultaneously strong and tough ultrafine continuous nanofibers. ACS Nano 7, 3324–3331 (2013).

    Article  CAS  Google Scholar 

  11. Prasher, R. Thermal interface materials: historical perspective, status, and future directions. Proc. IEEE 94, 1571–1586 (2006).

    Article  CAS  Google Scholar 

  12. Kurabayashi, K., Asheghi, M., Touzelbaev, M. & Goodson, K. E. Measurement of the thermal conductivity anisotropy in polyimide films. J. Microelectromech. Syst. 8, 180–191 (1999).

    Article  CAS  Google Scholar 

  13. Lu, G. et al. Drying enhanced adhesion of polythiophene nanotubule arrays on smooth surfaces. ACS Nano 2, 2342–2348 (2008).

    Article  CAS  Google Scholar 

  14. Xiao, R., Cho, S. I., Liu, R. & Lee, S. B. Controlled electrochemical synthesis of conductive polymer nanotube structures. J. Am. Chem. Soc. 129, 4483–4489 (2007).

    Article  CAS  Google Scholar 

  15. Martin, C. R. Nanomaterials: a membrane-based synthetic approach. Science 266, 1961–1966 (1994).

    Article  CAS  Google Scholar 

  16. Cannon, J. P., Bearden, S. D. & Gold, S. A. Effect of wetting solvent on poly (3-hexylthiophene)(P3HT) nanotubles fabricated via template wetting. Synth. Met. 160, 2623–2627 (2010).

    Article  CAS  Google Scholar 

  17. Shen, S., Henry, A., Tong, J., Zheng, R. & Chen, G. Polyethylene nanofibres with very high thermal conductivities. Nature Nanotech. 5, 251–255 (2010).

    Article  CAS  Google Scholar 

  18. Bazzaoui, E. A. et al. SERS spectra of polythiophene in doped and undoped states. J. Phys. Chem. 99, 6628–6634 (1995).

    Article  CAS  Google Scholar 

  19. Louarn, G., Buisson, J. P., Lefrant, S. & Fichou, D. Vibrational studies of a series of alpha-oligothiophenes as model systems of polythiophene. J. Phys. Chem. 99, 11399–11404 (1995).

    Article  CAS  Google Scholar 

  20. Shi, L. et al. Measuring thermal and thermoelectric properties of one-dimensional nanostructures using a microfabricated device. J. Heat Transfer 125, 881–888 (2003).

    Article  CAS  Google Scholar 

  21. Cahill, D. G., Watson, S. K. & Pohl, R. O. Lower limit to the thermal conductivity of disordered crystals. Phys. Rev. B 46, 6131–6140 (1992).

    Article  CAS  Google Scholar 

  22. Bullen, A. J., O'Hara, K. E., Cahill, D. G., Monteiro, O. & von Keudell, A. Thermal conductivity of amorphous carbon thin films. J. Appl. Phys. 88, 6317–6320 (2000).

    Article  CAS  Google Scholar 

  23. Liu, X. et al. High thermal conductivity of a hydrogenated amorphous silicon film. Phys. Rev. Lett. 102, 035901 (2009).

    Article  Google Scholar 

  24. Allen, P. B., Feldman, J. L., Fabian, J. & Wooten, F. Diffusons, locons and propagons: character of atomic vibrations in amorphous Si. Phil. Mag. B 79, 1715–1731 (1999).

    Article  CAS  Google Scholar 

  25. Feldman, J. L., Kluge, M. D., Allen, P. B. & Wooten, F. Thermal conductivity and localization in glasses: numerical study of a model of amorphous silicon. Phys. Rev. B 48, 12589–12602 (1993).

    Article  CAS  Google Scholar 

  26. Regner, K. T. et al. Broadband phonon mean free path contributions to thermal conductivity measured using frequency domain thermoreflectance. Nature Commun. 4, 1640 (2013).

    Article  Google Scholar 

  27. Osinin, S. & Nosov, M. Relation between the speed of sound and the orientation of chain molecules in anisotropic systems. Mech. Compos. Mater. 2, 4–6 (1966).

    Google Scholar 

  28. Cola, B. A. et al. Photoacoustic characterization of carbon nanotube array thermal interfaces. J. Appl. Phys. 101, 054313 (2007).

    Article  Google Scholar 

  29. Mohammad, F., Calvert, P. D. & Billingham, N. C. Thermal stability of electrochemically prepared polythiophene and polypyrrole. Bull. Mater. Sci. 18, 255–261 (1995).

    Article  CAS  Google Scholar 

  30. Otiaba, K. et al. Thermal interface materials for automotive electronic control unit: trends, technology and R&D challenges. Microelectron. Reliab. 51, 2031–2043 (2011).

    Article  Google Scholar 

  31. Cahill, D. G. & Pohl, R. O. Heat flow and lattice vibrations in glasses. Solid State Commun. 70, 927–930 (1989).

    Article  Google Scholar 

  32. Choy, C. L., Tong, K. W., Wong, H. K. & Leung, W. P. Thermal conductivity of amorphous alloys above room temperature. J. Appl. Phys. 70, 4919–4925 (1991).

    Article  CAS  Google Scholar 

  33. Taphouse, J. H. et al. Carbon nanotube thermal interfaces enhanced with sprayed on nanoscale polymer coatings. Nanotechnology 24, 105401 (2013).

    Article  Google Scholar 

  34. Taphouse, J. H., Smith, O. N. L., Marder, S. R. & Cola, B. A. A pyrenylpropyl phosphonic acid surface modifier for mitigating the thermal resistance of carbon nanotube contacts. Adv. Funct. Mater. 24, 465–471 (2014).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This work was supported by the National Science Foundation (NSF; grant no. CBET-1133071), a seed grant from the Georgia Tech Center for Organic Photonics and Electronics and an NSF-IGERT graduate fellowship for T.L.B. The work of Y.C. was supported by the Air Force Office of Scientific Research (award no. FA9550-09-1-0162). The work of K.H.S. was supported by the US Department of Energy, Office of Basic Energy Sciences (award no. DE-SC0002245). The work at UT Austin was supported by the NSF (award no. CBET-0933454). A.W. acknowledges support from the NSF Graduate Research Fellowship Program. K.D.B. was supported by the Natural Science Foundation of China (award no. 51205061), the Natural Science Foundation of Jiangsu Province (award no. BK2012340) and the National Basic Research Program of China (award no. 2011CB707605).

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Contributions

V.S., T.L.B. and B.A.C. conceived and designed the experiments. V.S. prepared the samples and performed the material spectroscopy and adhesion tests. T.L.B. performed the photoacoustic measurements. A.W., K.B., M.T.P., S.A.M. and L.S. performed the microbridge measurements. D.P.R., T.R.G. and D.H.A. performed the SiC chip tests. Y.C. and K.H.S. provided the TEM images and crystallinity characterization. W.L. and A.H. provided the single chain simulations. V.S., T.L.B. and B.A.C. analysed and discussed the data. V.S., T.L.B. and B.A.C. co-wrote the manuscript. All authors commented on the manuscript.

Corresponding author

Correspondence to Baratunde A. Cola.

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Competing interests

Georgia Tech has applied for a patent, application no. PCT/US 61/484,937, related to the design methods and materials produced in this work. Nanostructured composite polymer thermal/electrical interface material and method for making the same, B.A. Cola, K. Kalaitzidou, H.T. Santoso, V. Singh, US 2012/0285673 A1, November 15, 2012.

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Singh, V., Bougher, T., Weathers, A. et al. High thermal conductivity of chain-oriented amorphous polythiophene. Nature Nanotech 9, 384–390 (2014). https://doi.org/10.1038/nnano.2014.44

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