Polymer inverse opal

Cassagneau, T., and Caruso, E., Semiconducting polymer inverse opals prepared by electropolymerization, Adv. Mater., 14, 34, 2002. 

Ozaki, M., Shimoda, Y, Kasano, M. et al.. Electric field tuning of the stop band in a liquid-crystal-infiltrated polymer inverse opal, Adv. Mater., 14, 514, 2002. 

Cassagneau T, Caruso F (2002) Conjugated polymer inverse opals for potentiometric biosensing. Adv Mater 14 1837... 

Cassagneau, T., Caruso, F. Conjugated polymer inverse opals for potentlometiic blosenslng. Adv. Mater. 14, 1837-1841 (2002)... 

Polymer inverse opals (Figure 9.10) can be formed by partially or fidly filling the void spaces of a colloidal crystal with a liquid precursor by capillary action. These precursors are generally UVor thermally-curable polymers, such as polyurethenes or polyacrylates, epoxies with initiators, sol-gel materials or more recently conducting polymers like polypyrrole [113, 117-122]. The liquid precursors are then solidified and the original template is removed. This results in long-range ordered porous material with a predse periodic structure which has found use in many applications such as photonics, membranes and biosensors. 

Miguez, H Meseguer, F Lopez, C Lopez-Tejeira, F and Sanchez-Dehesa, J. (2001) Synthesis and photonic bandgap characterization of polymer inverse opals. Adv. Mater., 13 (6), 393-396. 

Fig. 11.14 (a) Reflection peak wavelength of polymer inverse opal infiltrated with 5CB as a function of applied voltage, (b) SEM image of polymer inverse opal... 

The porous membrane templates described above do exhibit three-dimensionality, but with limited interconnectedness between the discrete tubelike structures. Porous structures with more integrated pore—solid architectures can be designed using templates assembled from discrete solid objects or su-pramolecular structures. One class of such structures are three-dimensionally ordered macroporous (or 3-DOM) solids, which are a class of inverse opal structures. The design of 3-DOM structures is based on the initial formation of a colloidal crystal composed of monodisperse polymer or silica spheres assembled in a close-packed arrangement. The interconnected void spaces of the template, 26 vol % for a face-centered-cubic array, are subsequently infiltrated with the desired material. 

Figure 15.7 (a) The preparation of inverse opal photonic balls using polymer spheres and an inorganic... 

Ordered macroporous materials (OMMs) are a new family of porous materials that can be synthesized by using colloidal microspheies as the template. - The most unique characteristics of OMMs are their uniformly sized macropores arranged at micrometer length scale in three dimensions. Colloidal microspheres (latex polymer or silica) can self assemble into ordered arrays (synthetic opals) with a three-dimensional crystalline structure. The interstices in the colloidal crystals are infiltrated with a precursor material such as metal alkoxide. Upon removal of the template, a skeleton of the infiltrated material with a three-dimensionally ordered macroporous structure (inverse opals) is obtained. Because of the 30 periodicity of the materials, these structures have been extensively studied for photonic applications. In this paper, the synthesis and characterization of highly ordered macroporous materials with various compositions and functionalities (silica, organosilica, titana, titanosilicate, alumina) are presented. The application potential of OMMS in adsorption/separation is analyzed and discussed. 

The opals obtained by self-assembly are mechanically unstable because there is only Van der Waals force between spheres. The subsequent infiltration process could easily destroy the ordered colloid arrays. So we annealed the opals of polymer sphere to increase their stability. As a result, there would form interconnections between spheres, which come from the slight melting of the sphere surfoces. These necks can provide the opal with necessary mechanical stability. In addition, they are important for producing inverse opal structure. After infiltration, when the samples are treated with calcinations, these necks can act as channels for the transport of the products formed during calcination like CO2. 

Xu, T., Cheng, Z., Zhang, Q. et al.. Fabrication and characterization of three-dimensional periodic ferroelectric polymer-silica opal composites and inverse opals, J. Appl. Phys., 88, 405, 2000. 

FIGURE 4.6 Schematic showing the approach used to produce highly ordered inverse opal structures with conducting polymers. 

Figure 15.7 (a) The preparation of inverse opal photonic balls using polymer spheres and an inorganic scaffold (b) SEM image of the polymer template using balls of radius 463 2 mn. The spheres form a crystalline hexagonal array (reprinted with permission from [14] 2003 American Chemical Society). 

Instead of infiltration with neat metal nanoparticles, the interstitial voids of the template opal can also be filled wifh a mefal precursor. The impregnation of the preformed colloidal crystals with the metal precursor, followed by transformation of the precursor to the neat metal and removal of the template, results in metallic inverse opals. For example, nickel oxalate was precipitated in a PS opal and converted into a NiO macroporous network by calcination of the metal salt and combustion of the polymer. In a subsequent step, the nickel oxide was reduced to neat Ni in a hydrogen atmosphere to yield a macroporous metal network [82]. It was further suggested by the authors that by the same technique other metal networks (e.g.. Mg, Mn, Fe, Zn from their oxides and Ca, Sr, Ba etc. from their carbonates) should be accessible. 

N.A., Alexander, M., Vaia, R.A., 2004. Remotely actuated polymer nancxomposites—stress-recovery of carbon-nanotube-filled thermoplastic elastomers. Nat Mater. 3, 115-120. Copyright 2004, Macmillan Publishers Ltd. (B) Reproduced with permission from reference Yu, A., Meiser, F., Cassagneau, T., Caruso, F., 2004. Fabrication of polymer-nanopartide composite inverse opals by a one-step electrochemical co-deposition process. Nano Lett 4, 177-181. Copyright 2004, American Chemical Society. (C) Reproduced with permission from reference Fie, X., Shi, Q., Zhou, X., Wan, C., Jiang,... 

Yu, A., Meiser, E, Cassagneau, T, Caruso, E, 2004. Fabrication of polymer-nanoparticle composite inverse opals by a one-step electrochemical co-deposition process. Nano Lett. 4,177-181. 

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