Nonuniform

ace to hisinteresting edi- torial. between structure, composition, and properties ... components not present in the extremes. In some cases, it may be...
0 downloads 0 Views 2MB Size
GUEST EDITORIAL

Great New Products Have Their Origins in Great New Thoughts

The biography of our guest this month is written i n his extensiue xientifie publications over a period of 50 years. A YS&entific Weltmensch.” as I would describe Maurice Huggins, needs no reiteration of total accomplishments. The outlinebelow isasamplepref. ace to his interesting editorial.

After receiving the Ph.D. degree from the University of California (Berkeley) in 1922, Dr. Huggins was successively a t Harvard, the California Institute of Technology, Stanford, Johns Hopkins, and the Eastman Kodak Co. Retiring from the Kodak Lahoratories a t the end of 1958, he went to Stanford Research Institute, from which he retired in 1967. He is now a consultant and Senior Research Associate with the Arcadia Institute for Scientific Research. His researches have been largely concerned with the structure of matter-atoms, molecules, crystals, glasses, liquids, solutions-and with correlations

between structure, composition, and properties. He discovered the hydrogen bond (in 1919) and hydrogen-bonded helical and extended-chain structures for proteins. He is especially well known for his researches on polymer structures and properties. Currently, he is working in three scientific areas: a new theory of the thermodynamic properties of solutions, applications of his “structon” theory to various types of inorganic crystals and glasses, and the structures of anomalous water and related suhstances. THEEDITOR

Made-To-Order Nonuniform Materials

How should the composition of a material joining two dissimilar substances vary to give the strongest possible bonding? Can nonuniform glasses be advantageously substituted for the usual homogeneous lenses, prisms, and mirrors in a given type of optical apparatus?

New types of materials, requiring the development of preparative procedures radically different from those previously in use, occasionally become of great industrial interest. This has happened, for example, when synthetic elastomers were first developed as substitutes for natural rubber and when single crystals of certain inorganic substances, containing impurities of precisely prescribed types and amounts, became important for electronic applications. As I have suggested in a lecture on “Some Macromolecular Horizons” (to be published in Pure and Applied Chemistry), a similar situation may arise in the not-distant future with respect to nonuniform materials having compositions that change gradually, in an advantageous way, from place to place. A material in the form of a sheet, for example, might be much better for a given application if its composition changes gradually in a particular manner from one side of the sheet to the other. Consider, for example, such problems as the following:

If it should appear that a nonuniform material, conforming to certain specifications, is desirable, the next problem is to devise a practical method for its synthesis. Even if all the compositions required are known to exist stably, as in many metal alloys, inorganic glasses, and other types of solid solution, new techniques may have to be developed for producing the specified variation of composition with location. If the two extreme compositions are widely different, such as a metal and a nonmetallic compound of an inorganic glass and an organic elastomer, it may he necessary to use, for intermediate compositions, one or more components not present in the extremes. In some cases, it may be necessary or useful to employ eutectic mixtures or sintered powder mixtures of two different compositions, with the proportions of the two phases gradually varied. All I wish to do here is to suggest that some advance thinking about these problems, with regard to materials or applications in your special field of activity, may prove rewarding-and perhaps even interesting.

How should the composition of a sheet material change so as to stop a given projectile, travelling at a given velocity, with a minimum thickness of the sheet?

MAURICE L. HUGGINS 135 Northridge Lane Woodside, Calif. 94062 Ind. Eng. Chem. Prod Res. Develop.,Vol. 9, No. 2, 1970

121