T. Dermis, S. Mayavan, N.K. Dutta, N.R. Choudhury and S. Holdcroft
block copolymer, fuel cell, fuel cell membrane, PEFM, polymer nanomaterials
Block copolymers [1,2] and ionomers comprising fluoro/non-fluoro segments have significant potential applications in the field of fuel cell. However, they are very difficult to synthesize; because fluoro monomers are not amenable to living ionic polymerization or pseudo-living radical polymerization . Recently, Holdcroft et al.  have successfully synthesized a series of high molecular weight block copolymers of poly (vinylidene difluoride hexafluoropropylene)-b-poly(methyl methacrylate), P(VDF-co-HFP) b-PMMA and Poly (vinylidene difluoride hexafluoropropylene)-b-sulfonated poly(styrene). Such block copolymers (BCP) can act as templates to enhance ordering of nanoparticles within one phase and tailor permeability, proton transport, catalytic properties. Here we report the preparation and properties of these novel block copolymer nanocomposites for fuel cell applications. We incorporated organometallic precursors into three different polymer matrices (varying block ratios) and then formed mixed metal oxide or metallic nanoparticles within the BCP. Effect of block compositions and environment on the self-organisation and nanoparticle deposition behaviour has been investigated using microscopic, spectroscopic and scattering techniques. The results demonstrate that the nanocomposites exhibit selective binding of nanoparticles onto specific regions of the phase-separated BCP. This method allows preparation of simple patterned surfaces or films with consequent ability to prepare ordered nanocomposites via interfacial wetting with required performance characteristics. References 1. A. Ciferri, ‘Supramolecular Polymers’ Marcel Dekker, Inc.2000. 2. N. K. Dutta, A. K. Bhowmick and N. Roy Choudhury, ‘Thermoplastic Elastomers' in Handbook of Thermoplastics, ed. O. Olabisi, Marcel Dekker, New York, 1997. 3. K. Matyjaszewski and J.Xia, J. Chem. Rev. 101, 2991, 20013. Z. Shi, S. Holdcroft, Macromolecules, 37, 2084, 2004. 4. Z. Shi, S. Holdcroft, Macromolecules, 37, 2084, 2004.