The Miracle of Composites

Composites are solid materials that result when two or more substances are combined to form a new substance containing properties that are superior to those of the original ingredients. This can be illustrated by the synthetic composite fiberglass, which is commonly used in boat hulls, fishing rods, bows, arrows, and other sporting goods.a Fiberglass is made by setting fine fibers of glass in a liquid or jellylike matrix of plastic (called a polymer). When the polymer hardens, or sets, the end result is a composite that is lightweight, strong, and flexible. If the kinds of fibers and the matrix are varied, an enormously broad range of products can be made. Of course, man-made composites are still crude compared with those found naturally in humans, animals, and plants.

In humans and animals, instead of fibers of glass or carbon, a fibrous protein called collagen forms the basis of the composites that give strength to skin, intestines, cartilage, tendons, bones, and teeth (except for the enamel).b One reference work describes collagen-based composites as being “among the most advanced structural composite materials known.”

For example, consider tendons, which tie muscle to bone. Tendons are remarkable, not just because of the toughness of their collagen-based fibers but also because of the brilliant way these fibers are woven together. In her book Biomimicry, Janine Benyus writes that the unraveled tendon “is almost unbelievable in its multileveled precision. The tendon in your forearm is a twisted bundle of cables, like the cables used in a suspension bridge. Each individual cable is itself a twisted bundle of thinner cables. Each of these thinner cables is itself a twisted bundle of molecules, which are, of course, twisted, helical bundles of atoms. Again and again a mathematical beauty unfolds.” It is, she says, “engineering brilliance.” Is it any surprise that scientists speak of being inspired by nature’s designs?—Compare Job 40:15, 17.

As mentioned, man-made composites pale when compared with those of nature. Still, synthetics are remarkable products. In fact, they are listed among the ten most outstanding engineering achievements of the past 25 years. For example, composites based on graphite or carbon fibers have led to new generations of aircraft and spacecraft parts, sporting goods, Formula One race cars, yachts, and lightweight artificial limbs—to mention just a few items in a rapidly growing inventory.