Tunable Properties

Breedveld V., Nowak A.P., Sato J., Deming T.J., and Pine D.J. Rheology of block copolypeptide solutions Hydrogels with tunable properties. Macromolecules, 37, 3943, 2004. 

The consideration that many zeolite types exist, each with many tunable properties (e.g., pore size and alumina content), leads not only to a wealth of options but also to a high level of complexity. Owing to this complexity and limited understanding of zeolite formation and permeation behavior, a lot of experimental effort is required in this field, slowing down developments toward successful application. 

In this chapter, we demonstrate the design of high surface area catalysts with controlled, tunable properties... 

In recent years, nano has become a hot topic in materials science. The common theme here is always size matters and over the last decades, researchers have developed exciting new materials with unique and tunable properties. In this... 

W. Wang, J. Xu, and Y.-H. Lai, Alternating conjugated and transannular chromophores tunable property of fluorene-paracyclophane copolymers via transannular tt-tt interaction, Org. Lett., 5 2765-2768, 2003. 

During the last ten years, studies of luminescence and photochemistry of polypyridyl Ru(II), Rh(III) and Co(III) complexes, porphyrins and uranyl salts, in the presence of biological macromolecules such as DNA, have been the focus of increasing research work. The interest in such coordination compounds stems from their easily tunable properties. Not only their size and shape but also their... 

Nair KP, Breedveld V, Week M. Complementary hydrogen bonded thermoreversible polymer networks with tunable properties. Macromolecules 2008 in press. 

Such facets of dynamic metal-ligand binding offer a range of tunable properties in MSPs. We now discuss a selection of examples that reveals how these systems differ from typical covalent polymers and small molecule metal complexes yet combine the properties of both to form a new class of materials. 

With the aim of preparing photoinduced electron transfer devices or simply to be used as fluorescent reporter groups, the synthesis and utility of pyrene-L-alanine have been reported on several occasions. Regarding the development of charge-transfer devices, it was shown that intramolecular electron transfer occurred in 310- and a-helical peptidic systems, such as 182 and 185, between a pyrene and a dimethylaminophenyl chromophore (Scheme 51).[95 101] The rates depend on the relative orientation of the chromophoric side chains and on the framework conformation. Therefore, the preparation of tailor-made charge-transfer devices with tunable properties can be envisaged. 

Budarin, V., J.H. Clark, J.J.E. Hardy, R. Luque, K. Milkowski, S.J. Tavener and A.J. Wilson, Starbons New Starch-Derived Mesoporous Carbonaceous Naterials with Tunable Properties, Angewandte Chemie International Edition, 45, 3782-3786 (2006). 

Synthesis of metal nanostructures with tunable properties (optical, magnetic, electronic, catalytic, etc.), in specific physicochemical environments, is today of great importance from a fundamental as well as an applied point of view. Since the physicochemical properties of nanostructures are strongly dependent not only on the size but also on the shape, controlling the architecture of metal nanoparticles... 

In comparison with classic Lewis acids derived from main group halides (e.g., B, Al, Sn), f-elements, and early transition metal halides, late transition metal Lewis acids often are more inert to ubiquitous impurities such as water, offer higher stability, tunable properties by ligand modification, and a well-defined structure and coordination chemistry, thus allowing detailed studies of reaction mechanisms, and a rational basis for catalyst optimization. Among this new class of late transition metal Lewis acids, ruthenium complexes - the subject of this chapter - display remarkable properties... 

Growing interest is being paid to the preparation of nano-structured materials with sought-after properties. The hydrolysis-condensation of organo-alkoxysilanes represents a mild process to achieve hybrid silicas with tunable properties owing to the wide variety of organic components one can incorporate in these solids [1,2]. 

Dense gases are fluids that are near or above their critical points, generally with reduced temperature and pressure between 0.9 and 1.2. Near-critical fluids exhibit distinctive properties such as low viscosity, high diffusivity, low surface tension, and solvation power. Because the properties of DGs are dependent on pressure and temperature, they offer a unique environment with tunable properties that is ideal for the formulation of pharmaceuticals. 

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