Materials Science and Engineering for the 1990s Maintaining Competitiveness in the Age of Materials (1989) / Chapter Skim
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Appendix A: Synthesis
Appendix A: Synthesis
Pages 207-223
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From page 209... ...
· Close interactions between scientists and engineers engaged in materials synthesis, characterization, processing, and, ultimately, manufacturing are highly desirable in order to achieve rapid economic exploitation of research in synthesis. · While U.S.
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From page 210... ...
Additional findings of the committee are as follows: · New educational experiences for many scientists and engineers will be required if the materials research community is to be able to carry out tightly coupled programs in synthesis, characterization, analysis, and processing. Both undergraduate and graduate academic curricula need to be reexamined with the goal of helping students achieve a level of basic understanding of materials synthesis and materials properties that will allow them to participate in fruitful exchanges of research ideas.
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From page 211... ...
This general decline of industrial research has posed a dilemma for this committee throughout its various attempts to formulate meaningful recommendations, and the difficulty seems particularly severe with regard to research in synthesis. On the one hand, the committee strongly believes that research directly related to the synthesis of commercially useful materials can be performed successfully only in an industrial environment.
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From page 212... ...
Another reason for the blurred distinction is that modern techniques for preparing materials often are direct combinations of what we conventionally have considered to be separate operations of synthesis and processing. A pertinent example here is the reactive injection molding of polymers in which the synthetic chemical reactions occur simultaneously with the "process" of molding.
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From page 213... ...
While this situation is not necessarily bad, the lack of special expertise in synthetic chemistry leads to dependence on standard chemicals that can be acquired from commercial sources and standard methods of materials preparation. It seems likely that really new approaches to the design of materials systems will require novel synthetic techniques.
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From page 214... ...
Since about 1970, the United States has relied largely on foreign laboratories for the synthesis of new chemical compounds. The common experience was that foreign scientists would publish compositions and structures but would not be very quick to study the properties of novel materials.
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From page 215... ...
. Much of the best work in this field is now being carried out in Japan, where scientific leaders were early to recognize the need for strong coupling between synthesis and other areas of materials research, and have acted to meet this need by supporting appropriate programs at universities and at industrial and state-supported laboratories.
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From page 216... ...
information Industry The large-scale need for synthesis of new polymeric materials is a relatively recent development in the information industry. Until a few years ago, the only places where polymers played key roles in the manufacture of large mainframe computers were in lithographic processes for patterning metal lines and in the bindings of the particulate disks used for magnetic storage.
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From page 217... ...
Increasing the density of devices on chips requires development of submicron metal lines and an increase in the depth of circuitry from two or three levels to five or six. These developments will require, respectively, new photoresists with strong sensitivities at short wavelengths, and insulating polymers that planarize and have unusually low dielectric constants.
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From page 218... ...
For example, there is no fuel cell capable of directly consuming liquid fuel because there is no known electrode at which such fuels can be oxidized at useful rates. Development of new electrode catalysts for fuel cells might lead to dramatic improvements in the efficient use of energy resources and could help solve pollution problems.
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From page 219... ...
The synthesis of such materials requires improved understanding of the physics of detection and of the properties of materials that will be needed to defy detection. The interplay between synthesis, processing, and physics in this area must be strong, especially if the resulting materials are to maintain structural properties with minimal increase in mass and volume.
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From page 220... ...
The success of molecular precursors in solid-state synthesis often depends upon the use of ultrapure molecular materials. For example, a promising new method for producing ceramic fibers starts with the synthesis of a preceramic polymeric material that can be processed into a fiber and then py
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From page 221... ...
Organic nonlinear optical materials provide another illustration of the opportunities for research in the synthesis of ultrapure substances. It is becoming widely appreciated that the nonlinear optical properties of organic and organometallic molecules can be superior to those of inorganic solids.
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From page 222... ...
New Synthetic Methods At present, too little research is being carried out in the United States on truly novel synthetic methods. Most current research on synthesis emphasizes the use of conventional techniques for tailoring structures of molecules to achieve specific properties.
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From page 223... ...
A final example of novel synthesis concerns solid-state preparation techniques. The most commonly used methods involve reacting mixtures of powdered substances at high temperatures.
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