The Miracle of Silk

Spider silk is five times stronger than steel of the same thickness. Steel, known for being one of the strongest materials in the world, is an alloy produced in large factories in a series of processes. Spiders' silk, however, five times stronger than steel, is not produced in large factories: it is made by an arachnid. Just about any spider we can see anywhere can produce it. Another striking feature of the silk is that it is very light. We can demonstrate this with an example. A silk thread stretching around the whole world would only weigh 320 grams.(1) In addition, spider silk can stretch to four times its own length. It is very difficult to find a material both strong and elastic. For example, steel cables are one of the strongest materials around. But because they are not elastic like rubber, they slowly lose their shape. And although rubber cables do not lose their shape, they are not strong enough to lift heavy weights. On the other hand, as has been described above, spider silk is five times stronger than steel wire of the same thickness, and 30 percent more elastic than rubber of the same thickness.(2)
Spiders make different threads in their bodies for different purposes. These silks, in the same way as they have different qualities from the point of view of strength and elasticity, also exhibit different thicknesses and levels of stickiness. For example, although the dragline, which plays such a large part in the spider's life, does not possess the quality of stickiness, it is nevertheless strong and elastic. It can easily bear weights up to two or three times the weight of the spider. It is thanks to this silk that the spider, carrying the prey it has caught, can move safely up and down.