10. Materials Made To Measure
Until the end of the twentieth century, the discovery of new materials
was a haphazard and empirical process. We do not know how silk and
paper were invented in ancient China, but we can be certain that
no one understood the first thing about why they have their particular
and attractive properties. Copper was perhaps first smelted in the
Middle East as a by-product of pigment manufacture. Even the earliest
synthetic polymers and plastics-cellulose nitrate, vulcanized rubber,
bakelite-were chance discoveries, whose discoverers knew next to
nothing of their material's composition.
As we enter the twenty-first century, things are fundamentally
different. We have an entirely different attitude to materials discovery.
Serendipity will never become obsolete, for science has always depended
on an element of luck coupled to a prepared mind. But materials
are being not so much discovered as invented: designed for the job,
their components rationally selected and assembled for specific
functions. Even steels have become highly designed materials, with
carefully blended compositions to suit different roles. A report
by the US National Academy of Science in 1997 put it like this:
"Our knowledge now gives us unprecedented control over the structure
and properties of materials."
Several factors have made this possible. Materials scientists now
have at their disposal a vast array of techniques for probing the
most intimate structural features of materials: new microscopes
that can provide images at atomic resolution, scattering methods
for deducing crystal structures of the tiniest samples, spectroscopic
probes which reveal the subtleties of chemical bonding. Fabrication
methods permit the control of structure over a wide range of length
scales. The ability to design molecules that interact and assemble
in highly specific and predictable ways has had a great impact on
the synthesis of molecular materials. Increases in computer power
enable theorists to predict many properties of a hypothetical material-electronic,
mechanical, optical-based on a knowledge of nothing more than how
the atoms are arranged. A greater understanding of the mechanisms
of cell biology guide the design of new materials sympathetic to
the processes of life. These developments provide many handles for
manipulating the material world.
At the same time (and for much the same reasons), materials science
has emerged as an expanding interface between many diverse disciplines,
at which there are rich seams of fundamental science to be mined.
And so the discipline has been transformed from a branch of engineering
to one of the mainstreams of fundamental and applied science, attracting
fruitful collaboration between scientists of all persuasions.
Regardless of whether this or that material mentioned in this article
proves to be a winner in the marketplace, the impact of these changes
will be profound, not only in science but in daily life. The future
of information technology, energy production, transportation, space
technology, medical science and chemical engineering all depend
to a considerable degree on the invention of new materials. These
will surely be the products of exquisite planning and execution,
fabrics tailored to perform feats unimaginable in traditional materials.
With such capabilities at our fingertips, society will be confronted
more strongly than ever with the responsibility to make wise choices
about the technologies it creates.
Bibliography
Amato I. (1997). Stuff: The Materials the World is Made of. New
York: Basic Books. [Describes the emergence of materials science
as an independent discipline, and provides some vignettes of current
themes.]
Ball P. (1997). Made To Measure: New Materials for the 21st Century.
New Jersey, US: Princeton University Press. [A survey of current
developments and trends in materials science intended for the non-scientist.]
Bard A. J. (1994). Integrated Chemical Systems. New York: John
Wiley. [A more technical book that looks at the interfaces between
chemistry, biology and electronics and the "modular" approach to
molecular-based technologies.]
Bloor D., Brook R. J., Flemings M. C., and Mahajan S. eds. (1994).
The Encyclopaedia of Advanced Materials. Oxford, UK: Pergamon. [A
comprehensive overview of current materials science, written at
a somewhat technical level.]
Olson G. B. (2000). Designing a new material world. Science 288,
993-998. [A historical survey of materials engineering, with particular
emphasis on metals and alloys.]
Biographical Sketch
Philip Ball is a science writer and a consultant editor for Nature,
the international journal of science. He was an editor for physical
sciences with Nature for over 10 years. He is also Science Writer
in Residence at University College, London. Philip Ball's books
include Made To Measure: New Materials for the 21st Century (Princeton
University Press, 1997) and H2O: A Biography of Water (Weidenfeld
and Nicolson, 1999). He writes on all areas of science for the international
press and in the scientific literature. Philip holds a degree in
Chemistry from the University of Oxford, and a Ph.D. in physics
from the University of Bristol, UK.
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