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Scientists Crack Silk's Secret
AEton writes "Researchers at Tufts University have reportedly discovered the mechanism by which spidersilk is produced. Besides the obvious use as a Kevlar substitute in bulletproof vests, silk has applications in microprocessor production, nanoscale optical fiber, a and any other application requiring strength and flexbility. Scientists have long grappled with the issue of creating silk; artificial silk is inferior to the real stuff, and the spiders can't be farmed (when you put them too close together, they eat each other). The method these Tufts researchers have found makes "strong silk" production feasible; if they can make it economical, the impact on safety equipment alone makes this material a worthwhile investment."
Searching ScAm's Ask the Expert section, I found the following:
"Dragline silk [a kind of silk all spiders make] is a composite material comprised of two different proteins, each containing three types of regions with distinct properties. One of these forms an amorphous (noncrystalline) matrix that is stretchable, giving the silk elasticity. When an insect strikes the web, the stretching of the matrix enables the web to absorb the kinetic energy of the insects flight. Embedded in the amorphous portions of both proteins are two kinds of crystalline regions that toughen the silk. Although both kinds of crystalline regions are tightly pleated and resist stretching, one of them is rigid. It is thought that the pleats of the less rigid crystalline regions not only fit into the pleats in the rigid crystals but that they also interact with the amorphous areas in the proteins, thus anchoring the rigid crystals to the matrix. The resulting composite is strong, tough, and yet elastic."
SiLK which is used for microprocessor applications is not connected in any way to spider silk. The former is an acronymn for a resin
(aromatic hydrocarbon) made by Dow Chemicals and used by IBM and other chip companies as an insulator between the multiple layers of wires on a chip. Silicon Low-K = SiLK
http://us.expasy.org/spotlight/articles/sptlt02
"Spider silk is 40 times finer than human hair and right up to World War II, it was used for crosshairs in optical devices such as microscopes, guns and bomb-guiding systems. In fact, though crosshairs are now etched or made with metal filaments, some military facilities still keep a domesticated black widow spider as a silk provision for old instruments. To this day, Australian aborigines use the silk of a giant spider for fishing lines."
Knowing how to collect Black Widow silk is essential if you are repairing and restoring old microscopes and other optical equipment. They are not aggressive, and live a long time, and are content in a very small container.