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Aligned two- and three-dimensional structures by directional freezing of polymers and nanoparticles

Abstract

The preparation of materials with aligned porosity in the micrometre range is of technological importance for a wide range of applications in organic electronics, microfluidics, molecular filtration and biomaterials. Here, we demonstrate a generic method for the preparation of aligned materials using polymers, nanoparticles or mixtures of these components as building blocks. Directional freezing is used to align the structural elements, either in the form of three-dimensional porous structures or as two-dimensional oriented surface patterns. This simple technique can be used to generate a diverse array of complex structures such as polymer–inorganic nanocomposites, aligned gold microwires and microwire networks, porous composite microfibres and biaxially aligned composite networks. The process does not involve any chemical reaction, thus avoiding potential complications associated with by-products or purification procedures.

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Figure 1: Freeze-aligned porous polymers and polymer–nanoparticle composites.
Figure 2: Control over pore spacing by varying freezing rate.
Figure 3: Aligned PVA–cerium oxide (PVA–CeO2) composite.
Figure 4: Two- and three-dimensional aligned GNP structures.
Figure 5: Qualitative theoretical framework for the inclusion of particles in ice.
Figure 6: Complex interpenetrating composite materials.
Figure 7: Aligned porous biodegradable polymer.

References

  1. 1

    Gu, H., Zheng, R., Zhang, X & Xu, B. Using soft lithography to pattern highly oriented polyacetylene (HOPA) films via solventless polymerization. Adv. Mater. 16, 1356–1359 (2004).

    Article  Google Scholar 

  2. 2

    Quake, S. R. & Scherer, A. From micro- to nanofabrication with soft materials. Science 290, 1536–1540 (2000).

    Article  Google Scholar 

  3. 3

    Yamaguchi, A. et al. Self-assembly of a silica-surfactant nanocomposite in a porous alumina membrane. Nature Mater. 3, 337–341 (2004).

    Article  Google Scholar 

  4. 4

    Adelung, R. et al. Strain-controlled growth of nanowires within thin-film cracks. Nature Mater. 3, 375–379 (2004).

    Article  Google Scholar 

  5. 5

    Xu, C. Y., Inai, R., Kotaki, M. & Ramakrishna, S. Aligned biodegradable nanofibrous structure: a potential scaffold for blood vessel engineering. Biomaterials 25, 877–886 (2004).

    Article  Google Scholar 

  6. 6

    Mahler, W. & Bechtold, M. F. Freeze-formed silica fibres. Nature 285, 27–28 (1980).

    Article  Google Scholar 

  7. 7

    Mukai, S. R., Nishihara, H. & Tamon, H. Formation of monolithic silica gel microhoneycombs (SMHs) using pseudosteady state growth of microstructural ice crystals. Chem. Commun. 874–875 (2004).

  8. 8

    Fukasawa, T., Ando, M., Ohji, T. & Kanzaki, S. Synthesis of porous ceramics with complex pore structure by freeze-dry processing. J. Am. Ceram. Soc. 84, 230–232 (2001).

    Article  Google Scholar 

  9. 9

    Butler, M. F. Growth of solutal ice dendrites studied by optical interferometry. Cryst. Growth Des. 2, 59–66 (2002).

    Article  Google Scholar 

  10. 10

    Butler, M. F. Instability formation and directional dendritic growth of ice studied by optical interferometry. Cryst. Growth Des. 1, 213–223 (2001).

    Article  Google Scholar 

  11. 11

    Butler, M. F. Freeze concentration of solutes at the ice/solution interface studied by optical interferometry. Cryst. Growth Des. 2, 541–548 (2002).

    Article  Google Scholar 

  12. 12

    Hussain, I., Brust, M., Papworth, A. J. & Cooper, A. I. Preparation of acrylate stabilized gold and silver hydrosols and gold-polymer composite films. Langmuir 19, 4831–4835 (2003).

    Article  Google Scholar 

  13. 13

    Uhlmann, D. R., Chalmers, B. & Jackson, K. A. Interaction between particles and a solid-liquid interface. J. Appl. Phys. 35, 2986–2993 (1964).

    Article  Google Scholar 

  14. 14

    Körber, Ch., Rau, G., Cosman, M. D. & Cravalho, E. G. Interaction of particles and a moving ice-liquid interface. J. Cryst. Growth 72, 649–662 (1985).

    Article  Google Scholar 

  15. 15

    Rempel, A. W. & Worster, M. G. The interaction between a particle and an advancing solidification front. J. Cryst. Growth 205, 427–440 (1999).

    Article  Google Scholar 

  16. 16

    Butler, R., Hopkinson, I. & Cooper, A. I. Synthesis of porous emulsion-templated polymers using high internal phase CO2-in-water emulsions. J. Am. Chem. Soc. 125, 14473–14481 (2003).

    Article  Google Scholar 

  17. 17

    Zhang, H. & Cooper, A. I. Synthesis of monodisperse emulsion-templated polymer beads by oil-in-water-in-oil (O/W/O) sedimentation polymerization. Chem. Mater. 14, 4017–4020 (2002).

    Article  Google Scholar 

  18. 18

    Recknor, J. B., Recknor, J. C., Sakaguchi, D. S. & Mallapragada, S. K. Oriented astroglial cell growth on micropatterned polystyrene substrates. Biomaterials 25, 2753–2767 (2004).

    Article  Google Scholar 

Download references

Acknowledgements

We thank Unilever and EPSRC (Portfolio Partnership in Complex Materials Discovery, EP/C511794/1) for financial support. A.I.C. thanks the Royal Society for a University Research Fellowship.

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Correspondence to Andrew I. Cooper.

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Zhang, H., Hussain, I., Brust, M. et al. Aligned two- and three-dimensional structures by directional freezing of polymers and nanoparticles. Nature Mater 4, 787–793 (2005). https://doi.org/10.1038/nmat1487

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