Ask someone for a fact about New Zealand and chances are they’ll likely say, “There are more sheep than people.” It’s true, with 30 million sheep to 4.4 million humans, so it is little wonder that wool production is a major source of export revenue, and national pride, for the country. But the industry is in serious decline. Total wool exports fell 30.2 percent to NZ$367 million ($251.3 million USD) in the year to January 2021, and with wool prices so low it can often cost farmers more to shear sheep than they can get for the wool once sold.
We’re not talking about luxury Merino wool here. That ultrafine fiber still commands a high price, but it makes up only 10 percent of New Zealand wool products. Some 80 percent of New Zealand wool is actually strong wool, a coarser natural fiber more typically used for carpets and rugs.
Changing tastes and the popularity of man-made fibers means there’s a surfeit of strong wool in New Zealand—an estimated 1 million tons is stored waiting for the prices to improve—but 26-year-old inventor Logan Williams, and his company Shear Edge, is hoping to make the most of this increasingly ignored material by chopping it up and using it to make boats, knives, fencing, and just about anything that’s currently made using plastic.
Williams has pioneered a method of adding processed strong wool to polymers, including bio-based PLA (polylactic acid), typically made from corn starch. The result is a material that not only uses less plastic but is lighter and stronger—and, crucially, this wooly plastic can be processed by existing plastic-forming machinery.
“Wool is composed of keratin protein,” explains Williams. “It’s actually one of the strongest natural materials on the planet, so when it gets infused with the polymer it makes it incredibly strong, but also lighter, so the more wool we can put into the polymer the lighter the products will be and less plastic will be needed.”
The pellets, made in Shear Edge’s Hamilton factory, south of Auckland on New Zealand’s North Island, can be used as a substitute for plastic manufacturing without having to invest in new machinery. “Our pellets can be universally applied to almost all forms of manufacturing, says Williams. “This includes injection molding, extrusion, rotational molding, and thermoforming. Our customers may only have to slightly change the temperature and torque of their existing machinery, and aside from visible fibers, it looks almost identical to the industry standard.”
Shear Edge’s wool composites have been tested by Scion Research (a New Zealand government-owned company that carries out scientific research for the benefit of the country) to international ISO and ASTM standards, and the results show that wool makes composites lighter and stiffer, with higher impact and tensile strength.
Shear Edge is currently producing 4 tons a day, and Williams hopes that by using strong wool, he can give farmers an income stream for a product that is often considered worthless, especially as they can use parts of the fleece such as bellies, side,s and pieces that would otherwise be thrown away. Currently the company’s formula replaces as much as 35 per cent of the typical base polymer without a reduction in performance. It’s also worth noting that, unlike a material such as glass fiber, it is 100 percent recyclable.
“We’re trying to make pellets that can be ubiquitously added to any factory and lower the barrier of entry. So any customer can take our pellets and make their products,” says Williams.
So far Shear Edge has partnered with a number of companies to showcase its woolly pellets, including making handles for New Zealand-based Victory Knives, hi-tech fencing—for the sheep farming industry, obviously—and both a kayak and catamaran, the latter of which will be thoroughly tested by making the choppy crossing of the Cook Strait, which separates the North and South Islands of New Zealand, in February.
While keen to promote environmentally favorable and biodegradable solutions such as PLA, Shear Edge pellets are versatile enough to be incorporated with most common polymers including PHA, HDPE, LDPE, PP, PET, PA and PVC.
But no matter what base material is used, the pellets will reduce the amount of plastic in circulation. A standard kayak usually weighs 20 kilgrams, but by adding wool it drops to 18 kg, which equates to a saving in the region of around 2,000 plastic bags. Yes, it’s a drop in the proverbial ocean compared to the 9 million tons dumped in the oceans each year, but Williams is hoping that an innovation that benefits supplier, manufacturer, and planet will catch on to the extent that the numbers really do start to make a difference.
Shear Edge isn’t the only company looking to substitute wool for man-made materials. UK-based Solidwool has been producing bespoke furniture and accessories using a mix of Herdwick sheep wool and bio-resin for years, while a 2010 project between Scotland’s Strathclyde University and Spain’s University of Seville experimented with a reinforced eco-friendly brick made using a mix of wool and seaweed.
And back in New Zealand, Woolcool has designs on the 1 million tons of wool in storage for its brilliantly efficient natural alternative to cold shipping made using 100 percent felted sheep’s wool which is washed, scoured, and sealed within a recyclable polyethylene wrap. It’s fully biodegradable, can be added to compost, yet has been proven to keep food chilled for at least 24 hours.
The question is whether Shear Edge’s approach, which costs some 20 percent more than the equivalent polymer, will entice enough manufacturers to make the global impact Williams is hoping for. The company goal is to sell 50,000 tons of material a year and to have about 50 core customers across 25 different industries. “The higher cost is mostly because our philosophy is to deliver a higher wool price to our hard-working farms, while reinforcing environmentally conscious and ethical practices,” Williams says. “But if the stores do run dry, and in the unlikely event that the New Zealand wool industry does collapse, we’ll switch to using recycled wool or find alternatives from other countries.”