Arthropod silks are proteins. They can be produced through genetic engineering technology as a mass of protein in bioreactors. When arthropods produce silk strands they force the protein through a structure known as a spinnerette. The physical forces on the protein as it passes through the spinnerette turns the disorganized protein mass into linear strands. The limitation to production of artificial silks has been the lack of an artificial spinnereatte that will produce strands or threads.
The spinnerette hurdle has been overcome by at least one company. Bolt Threads. They have created a process to turn synthetic spider silk into thread and expect to produce a cloth commercially by 2018. The cloth may have some properties of silkworm silk but other unique properties. It may replace some uses of traditional silk, but more likely, it will have its own niche in the fabric and fashion industry.