Conclusions and Future Outlook

Smith and J. March, March s Advanced Organic Chemistry Reactions, Mechanisms, and Structure, 6th Edn., JohnWiley Sons, Hoboken, New Jersey, 2007, Chapter 12 (b) N. Isaacs, Physical Organic Chemistry, 2nd Edn., Longman, Essex, England, 1995, Chapter 10 (c) T.H. Lowry and K.S. Richardson, Mechanism and Theory in Organic Chemistry, 3rd Edn., Harper CoUins Publishers, New York, 1987, Chapter 6. 

Eliel and S.H. WUen, Stereochemistry of Organic Compounds, WUey-lnterscience New York, 1994 1120-1121. 

The use of SCF solvents for advanced materials synthesis and processing is a burgeoning field, as witnessed by the large number of breakthroughs in the last five years. For example, most of the research reviewed in this chapter was published in the three-year period 2002-2004. In general, there have been two main thrusts to this work  

the elimination of volatile organic solvents and polluted aqueous waste streams  

We suggest that commercialization of this technology in the materials area will be brought about by the successful convergence of these two approaches. 

A range of future opportunities exists for the exploitation of SCF solvents in various areas of materials science. The explosive growth of nanoscale materials applications in the last five years points to one such area. Another field that may hold great future promise is SCF solvent engineering in supramolecular chemistry this has, as yet, been Httle exploited, despite the growing understanding that exists concerning micelle formation and self-assembly in SCFs. 

Perhaps the best scientific acid test for materials produced using SCFs is whether or not the same materials could be produced using more conventional methods. In truth, it is hard to point to any materials produced so far that could not, in principle, be produced using more conventional liquid- or vapor-phase technologies. There are, however, a growing number of examples of advanced materials which can be produced very conveniendy using SCFs which would be difficult or inconvenient to produce by other routes. To give a few examples  

As a conclusion one can say that the distinction of islands of specific activity from within a sea of baseline toxicity, with each island representing a local chemical biological mechanism domain, is still a challenge to be solved by scientists working both experimentally and computationally. 

In this chapter, we discussed some interesting studies on ternary polymer composites containing both clay and CNTs. Synergistic effect is observed in composites as improvements in various properties (such as mechanical, electrical and thermal stability properties) are obtained. This effect between clay and CNTs in polymer composites indicates that the nanofillers with different dimensions can greatly cooperate with each other in certain way to improve the properties of the composites rather than work independently. More importantly, the improvement is more than a simple sum of 

Currently, the study on ternary polymer composites containing both clay and CNTs is still at its primary stage, but it is promising and exciting to assemble two types of nanoparticles to break the limitation of single nanofiller in composites. Furthermore, we would like to propose some issues that should be addressed in future work in this field  

One of the benefits of the methods discussed in this chapter is that they provide a complete characterization of the thermodynamics of transfer of solute from crystal to aqueous solution. Since the solubility of a crystalline solute depends upon the properties of the undissolved crystalline precipitate as weU as the properties of the solution, the thermodynamic data provides valuable information in understanding not only which of the two molecules is more soluble but also why the selected molecule is more soluble. By contrast, QSPR models, which are statistical rather than first-principles approaches, provide only limited statistical information about the underlying physicochemical processes. Moreover, since most QSPR models predict solubility from molecular rather than crystal structure, they are not able to rationalize or predict different solubilities for different polymorphs of a molecule. Therefore, we believe that the bottom-up methods that utilize efficiently molecular-scale information about the solute and solvent structure will attract more attention in the future in terms of both practical applications and fundamental studies of solubility of druglike molecules. 

MOLECULAR SIMULATION METHODS TO COMPUTE INTRINSIC AQUEOUS 

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