Spider silk: Tougher, sustainable alternative to synthetic textiles

Increasing awareness of the adverse effects the clothing and textiles industries have on the environment has prompted several companies to search for sustainable material options.

At present, many apparel manufacturers favor synthetic fabrics such as nylon, polyester and acrylic over natural variants as these are more durable, and boast consumer-friendly properties, including better stretch, and water- and stain-resistance. But because man-made textiles are often petroleum-based, it takes a very long time for these materials to decompose.

Enter the spider silk. The scene in the Spider Man 2 movie where Spider Man pulls a runaway train to a halt has some truth to it. According to experts, although silk that spiders produce is light and stretchy as a rubber band, its tensile strength is comparable to that of steel. These properties combined make the fiber tougher than Kevlar.

And these attributes are what inspired several companies to create a synthetic version.

Spiber Inc., a Japan-based biomaterials specialist, is among the first to successfully produce artificial spider silk. The company uses genetically modified E.coli. It also employs different microorganisms depending on the gene sequences the firm wants to create. Currently, Spider has developed more than 600 types of original proteins.

The company has already collaborated with Japan sportswear brand Goldwin Inc., The North Face's distributing arm in the country, to release a parka made of spider silk. The jacket, dubbed as the Moon Parka, was unveiled recently at The North Face's flagship store at 510 Fifth Avenue in New York. The retail date, however, is yet to be disclosed.

AMSilk from Germany claims to have produced the strongest synthetic spider silk yet. Called Biosteel, the fiber also adopts E.coli and was designed originally for use on surgical implants. The firm has partnered the sportswear giant adidas to release the Futurecraft Biofabric, a pair of biodegradable running shoes made of synthetic spider silk.

US-based startup Bolts Thread, meanwhile, has created its version using fermented yeast. The fibers undergo wet-spinning, a process similar to what isused in producing Lyocell. The company said using yeast is significantly less expensive than employing E.coli.

Bolt Thread has announced recently a $50 million funding and its partnership with outdoor brand Patagonia. The enterprises, however, have yet to divulge details on the products they are working on.

The main advantage of synthetic spider silk is that it is protein-based, which means the ingredients are renewable and biodegradable, unlike in petroleum-based fibers.

Producing the fabric in large quantities, however, prove to be a challenge. Spider silk also costs significantly more than popular synthetics such as nylon, polyester and acrylic.

But Bolt Threads is taking a positive step towards mass production. The company revealed that although it will not have a product on the market first, the firm has begun to produce silk in kilograms and plans to start turning out metric tons in coming months. It also intends to have some demo textiles and a few products up for sale in the next 12 to 18 months.