Artificial spider silk from Amsilk is more flexible and possibly better suited for high-performance applications than its rival, carbon fiber.

Amsilk, a southern German startup that makes artificial spider silk, hopes to soon be spinning bigger webs thanks to a fresh agreement with pan-European planemaker Airbus.

Next year, they’re aiming to present their first jointly-developed composite material, based on Amsilk’s synthetic biopolymer that was inspired by arachnid silk.

Amsilk is located in Martinsried, Germany, and owned by twins Andreas and Thomas Strüngmann. The Strüngmann brothers made their fortunes with Hexal, a generic drugmaker, and the company’s fibers came from research by Thomas Scheibel, a biomaterials professor at the University of Bayreuth.

The fibers are made by genetically modifying E.coli bacteria to produce spider silk proteins. These purified proteins are then dried into a silk powder, which can be put into textiles, cosmetics or used as the basis for lightweight composites.

Wings of Biosteel

Amsilk calls it “Biosteel” and says synthetic silk is resistant, flexible and soft, giving it an advantage over carbon fiber for use in implants and prosthetics, or even aviation. “The disadvantage of carbon is that aircraft are often grounded after a bump because parts have to be replaced,” said Amsilk boss Jens Klein. Minor damage to carbon fiber can be a big problem whereas Biosteel may be able to take the knock and remain in use.

“The technology has enormous long-term potential,” he said, “especially financially.”

Mr. Klein joined Amsilk in 2014 as CEO after stints at medical device and pharmaceutical maker Fresenius as well as chemical company Evonik. His contacts helped popularize Biosteel in cosmetics and led to a 2016 prototype for an Adidas shoe.

“Cosmetics is the lowest hanging fruit,” he said. Conventional nail polishes, for example, keep oxygen from passing through the nails but those made from synthetic silk allow water vapor and oxygen to the skin below. But, Mr. Klein said, mobility holds greater promise for the material, as well as higher regulatory demands.

Airbus will contribute financially to the agreement but will not take a stake in Amsilk.