Ability to tailor materials

The big revolutionary improvements in polyethylene technology have occurred in steps of 20 years (Fig. 1) [2]. In each new development step, catalyst and process innovations have gone hand-in-hand and the control over the polymer structure and the ability to tailor material properties have increased. Today ethylene can be polymerised under various conditions to yield polyethylenes having markedly different chain structures and physical... 

Design of organoboron polymer electrolytes will continue to have a great deal of potential based on the ability to tailor boron atoms. This is an attractive approach for single ion conductive materials. 

Dais membranes are reported to be much less expensive to produce than Nation they are also reported to exhibit a rich array of microphase-separated morphologies because of the ability to tailor the block length and composition of the unsulfonated starting polymer. The main drawback of employing hydrocarbon-based materials is their much... 

World War II helped shape the future of polymers. Wartime demands and shortages encouraged scientists to seek substitutes and materials that even excelled those currently available. Polycarbonate (Kevlar), which could stop a speeding bullet, was developed, as was polytetrafluoroethylene (Teflon), which was super slick. New materials were developed spurred on by the needs of the military, electronics industry, food industry, etc. The creation of new materials continues at an accelerated pace brought on by the need for materials with specific properties and the growing ability to tailor-make giant molecules macromolecules—polymers. 

Thin films of block copolymers are likely to find many applications as nanostructured materials, due to the ability to tailor nanoscale dot and stripe patterns. Theory for microphase separation in thin films, especially the effect of confinement on structure orientation is now quite advanced. " Models for the effect of confinement on thermodynamics have also been developed, although this aspect has attracted less attention. 

While establishing molecular networks for cocrystal design and determining crystal structures is very important, the value of cocrystals of pharmaceutical components lies in the ability to tailor the functionality of materials. In contrast to polymorphs that have the same chemical composition, cocrystals do not. As such, one would expect that with cocrystals one could introduce greater changes in material properties than with polymorphs. Properties that relate to pharmaceutical performance and that can be controlled by cocrystal formation include melting point, solubility, dissolution, chemical stability, hygroscopicity, mechanical properties, and bioavailability. The cocrystals for which pharmaceutical properties have been studied are few and some of these are presented below. Clearly further research in this area is needed. 

Polymers have unique versatility for many packaging applications in that their mechanical properties can be tailored, giving materials ranging from rubber-like gels with dramatic changes in modulus with temperature, to hard solids with almost no changes at all. Moreover, electrical properties can be varied to achieve, within limits, desired values of dielectric constant, low ionic conductivity, etc. Key concerns today often center on the ability to achieve simultaneously the desired mechanical and electrical properties, a difficult task. The ability to tailor the coefficient of thermal expansion, CTE (also often abbreviated TCE) to match that of the substrate or of other components is a subject of considerable interest. 

Most research-intensive universities are well equipped with characterization techniques such as electron microscopy, electron and x-ray diffraction, and probe microscopy, which are used routinely to characterize small structures, small volumes, and thin films. However, the ability to characterize extremely small nanostructures or to tailor materials at an atomic level requires much more specialized equipment. 

In practice, an infinite variety of polymer/inorganic particle combinations can be envisaged. This article has attempted to summarize the most important issues to be considered for successful formation of such nanocomposite colloids. The ability to tailor the affinity between the organic and inorganic parts is the key to a happy marriage between these two naturally incompatible compounds. However, despite the considerable advances, excitement, and promise of O/I composite latexes, substantial fundamental research is still necessary to provide a deeper understanding of current synthetic methods, develop new processes, and enable further exploitation of these materials. 

It has been suggested that a possible solution would be to replace these metal components with light-weight, high i>erformance composite materials consisting of polymeric materials. Such a composite material is believed to provide a relatively low elastic modulus as compared to metals, the absence of metal ion release products, and the ability to tailor the strength of the material to suit individusd design requirements. However, the problem of fixation in hard tissue of a polymeric component would still exist, as in the case of the current use of UHMWPE components. 

Much of the work that has been done up to this point on high temperature polymer blends is the definition of miscible blend polymer pairs and an understanding of the features that lead to that miscibility. The development of miscible blends often leads to the ability to tailor the properties, including the Tg of mixtures. Such a tailoring is an alternative to the development of entirely new polymeric materials with the desired property profile. One of the advantages of the blend approach is that it is generally faster and less expensive than the synthesis and scale-up of an entirely new polymer. The downside of the blend approach is that it is difficult to define miscible pairs and miscibility is often the situation that is not observed with polymer mixtures. 

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