The market
The global market for biocompatible polymers is estimated at $10 billion. According to the German Nova Institute, demand for bio-industrial plastics and composites is experiencing double-digit growth despite the economic crisis. Petroleum-derived polymers have replaced most natural substitutes and even metals. The introduction of engineered plastics has reduced the cost and weight of transportation vehicles and electronics. Naturally sourced polymers maintain a loyal customer base and are even increasing their market share. However, plastics made from corn starch compete with food, cotton consumes massive amounts of irrigation water and pesticides, and cellulose cellophane requires sulfuric acid in its production process. These examples imply that polymers derived from renewable resources are not necessarily sustainable.
Silk is historically the first industrialized polymer to become a market standard. Global silk production exceeded one million tons per year around 1900 but plummeted to 90,000 tons a century later, resulting in the loss of approximately 25 million rural jobs. Silk farming and processing were disrupted by China, India, Persia, Turkey, and Italy. Only a few luxury products, such as Hermès ties, survived as benchmarks of quality. Recently, production has rebounded to nearly 100,000 tons.
Innovation
When the Chinese began cultivating mulberry trees around 5,000 years ago, they focused on regenerating surface soils in arid lands to develop agriculture to meet their growing food demand. It was by chance that a cocoon fell into the Empress's teacup, and she pulled 300 meters of silk thread from the hot water. This discovery gave rise to a global industry. Silk has never been able to compete with the introduction of synthetic fibers, and few have undertaken fundamental research to identify the true potential of this renewable polymer.
Professor Fritz Vollrath and the Silk Group at the University of Oxford (UK) have studied natural polymers from bees, ants, mussels, spiders, and moths. Some spiders produce silk that surpasses titanium. This is the first silk with a high performance-to-weight ratio while also being biocompatible. The silk is absorbed by the body's tissues, whereas titanium is not rejected. Secondly, the silk of the mulberry worm, which is not a worm but a caterpillar, can be transformed into spider silk simply by controlling the pressure and moisture content. Thirdly, carbon-rich silk not only replaces a petroleum-derived polymer that emitted carbon during its production, but it also unlocks a positive cycle of carbon sequestration from tree planting to the production of biocompatible devices at low energy and pressure, creating a raw material that can be recycled indefinitely. If raw silk is obtained by traditional methods as is the case in Bhutan, the caterpillar is not boiled to death and offers a new perspective on human agriculture.
The first cash flow
While silk was once the standard raw material for fine clothing, this market has evaporated over the years. It will be very difficult for silk to enter the consumer goods market, where nylon has long since replaced natural polymers. The first portfolio of applications concerns medical devices. Fritz Vollrath founded Oxford Biomaterials and successfully created four companies, each focusing on clearly defined niches where silk has a competitive advantage. The four applications are: sutures, nerve repair, bone grafting, and orthopedic devices. Capital has been raised and partners have been confirmed for each application. The new companies spun off from Oxford Biomaterials are Neurotex, Suturox, and Orthrox, the latter being co-funded by the Welcome Foundation.
The simplest commercial product is sutures, those threads surgeons use to stitch us up after surgery. Braiding raw silk under sterile conditions is all that's required, followed by attaching a needle to the fiber. Mass production of standardized sutures is controlled by a few players like Johnson & Johnson. While it's possible to make little money with silk for textiles, a niche market like sutures could stimulate the revival of local industries operating within a niche market, replacing costly imports with local manufacturing that incorporates tree planting, rural jobs, and carbon sequestration, with a cash flow from added value that requires only limited investment to enter the market.
The opportunity
The potential applications of silk extend beyond medical devices. Certain consumer products also offer an extraordinary opportunity, although more product development is needed because there are no off-the-shelf designs for the fast-moving mass market of consumer goods. The razor is a clear target. A razor is made of titanium and stainless steel. It is estimated that 100,000 tons of high-quality metals from razors end up in landfills. The amount of stainless steel and titanium per razor has been reduced by a factor of 20 compared to the first versions invented by Mr. Gillette over a century ago. Lately, the total amount of highly processed metals, including titanium, is on the rise again, as the single blade has become a double, triple, and now even five-blade version, each time promising a closer shave.
It may seem unreasonable to suggest that a silk-based alternative could surpass the inventive capacity of Gillette's 500 full-time researchers. However, the new business model that might emerge could be so different that none of the three market leaders (Gillette, Schick, and BIC) could commit to such a fundamental shift. Instead of cutting the keratin (the hair) with a blade, the silk threads rolled across the skin, trimming the top of the hair just like old-fashioned hand clippers. A major advantage is that silk can only cut hair, never skin.
If the 100,000 tons of highly processed metals sent to landfill were replaced by silk, more mulberry trees would need to be planted, as the current global supply is only 100,000 tons. This planting requires approximately 1,250,000 hectares of mulberry trees on land, which is abundant worldwide. Planting, caterpillar rearing, and processing generate around 1,500,000 jobs while restarting the carbon sequestration cycle, surpassing any technological solution. The potential for introducing silk as a competitive product lies in niche markets where current consumer behavior is wasteful. The possibility of replacing titanium with something as smooth as silk has a clear commercial advantage that many are ready to exploit. What about you?
