Multifunctional material

The possibility of coordinating functionalized TTFs onto polynuclear core is a very stimulating issue because it is now well established that polynuclear cores, with some restrictions of course, can act as SMMs. We started a systematic investigation of polynuclear paramagnetic complexes with TTF CH=CH—py ligands to scan the possibility to access to bifunctional molecules which can act at the same time as SMM and single component metal. We succeeded in coordinating our modified TTFs to several homo- or heteropolynuclear complexes. This opens new perspectives in the field of multifunctional materials. The size of these molecules, which is of the order of 4 nm, is another important aspect in the field of molecular scale electronic. 

Acknowledgements This work has been supported by CICYT (BI02000-0351-P4-05, AGL2001-5005-E) and by the EC nanotechnology and nanosciences, knowledge-based multifunctional materials, new production processes and devices (contract number NMP-505485-1). 

The expected contribution of catalysis in this area will derive both from the availability, at low processing costs, of new monomers obtained from biomasses and from the development of an optimized combination of biotechnology processes with classical and new biocatalytic processes. Research priorities for catalysis in the area of polymers from renewable materials for packaging, furniture, domestic water purification and recycling include the need to develop novel catalysts, e.g., for functionalization of polymeric and dendrimeric materials, with side-chain photoactive molecular switches (to be used as smart materials), or the development of multifunctional materials, combining, for example, nanofiltration with catalytic reactivity. 

The example above shows that heterogeneous catalysts are multifunctional materials not at the nanometer but even at the atomic scale. A detailed structural understanding is a prerequisite for a targeted development of these eatalysts. This would be impossible without the help of modem TEM techniques. It can be expeeted, that the next generation of TEM instmments with Cs-corrected eondensor- and objective lenses in combination with high resolution energy electron loss spectrometers ean reveal stmetural and chemical details of eatalysts even at the atomie seale [10,11]. 

There is a definite trend in the supplier industry to develop multifunctional materials with value-added properties. One supplier has introduced a modified hydrocarbon resin that softens, improves filler incorporation, improves mill banding, and increases tack in the green compound while imparting increased low strain (<100%) stiffness, significandy improving tear resistance in the vulcanized compound. 

Functionally graded materials (FGMs) are multifunctional materials, which contain a spatial variation in composition and/or microstructure for the specific purpose of controlling variations in thermal, structural or functional properties. Also in the ceramics composites field, a wide range of functionally graded (FG) ceramics are available. Hence, a possible classification of the different classes is made in this chapter. 

In the near future, the use of multifunctional polymer-based materials with separation/selective transport capabilities is also to be expected in the design of production systems with integrated environmental protection or inthe combination of chemical reactions and separation by attaching a catalytic functionality to the respective material [1]. Thus, those multifunctional materials should contribute materially to the development of clean energy and/or energy saving and therefore sustainable production technologies. In connection with these perspectives, there is considerable interest in new/modified polymer-based materials with tailored transport/catalytic properties. Also, many sensor applications are based on controlled permeation. 

If we can combine ferroelectrically polarizable guest molecules with PCPMs, then we can obtain new types of multiferroic materials, where ferroelectricity and ferromagnetism coexist. Such multifunctional materials have recently aroused increasing interest from the viewpoint of the development of new materials with very large magnetoelectric effects. [Mn3(HCOO)6] EtOH is considered to be the first ferroelectric PCP.182 Because the desolvated compound [Mn3(HCOO)6] shows a very small and almost temperature-independent dielectric constant, irrespective of the direction of the electric field,183 the observed ferroelectric property is considered to come mainly from the guest EtOH molecules. 

The self-assembly of the various polymer systems described in the above sections is only a brief summary of the attempts by chemists to create multifunctional materials based on noncovalent interactions. The unique regions present within a polymer including the (1) main-chain/backbone, (2) end groups, (3) side-chains and (4) dendritic periphery, along with the ability to functionalize any of these regions with recognition units, provide chemists with a wide array of self-assembly possibilities with which to build and create multifunctional materials. 

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