Could Wool Fibers Replace Glass Fibers in FRP?

In New Zealand, surfboard maker Paul Barron has developed a new wild and wooly composite.

A few years ago, New Zealand surfboard maker Paul Barron spilled a bit of resin on his jersey, or maybe it was his jumper or his sweater, depending on which source you read. "I noticed how solid it went and the idea to replace fibreglass with wool began." That was the inspiration for his Woolight surfboard, now made by Kelly Slater's Firewire Surfboards.

I am sheepishly late to the story, having been recently pitched by New Zealand Trade and Enterprise, but Suzanne Labarre described how it is made in Fast Company last year:

The wool sheared off a sheep is up to 3 inches thick, with fibers flaring out in all directions. Barron developed a vacuum-pressure technique that converts this bulky material into a thin wool-and-bioresin composite, with a compression strength that rivals that of fiberglass and polyurethane. According to Firewire CEO Mark Price, the process reduces CO2 emissions by 40% and VOC emissions by half, compared with traditional construction.

Is this a real advance, or are they pulling the wool over our eyes? Barron tells the totally unbiased Sheep Central:

There are several advantages of wool over fibreglass. It is far nicer to work with, there is less waste – I can reuse the wool on the cutting floor – and it requires less resins. The ZQ wool that we use is ethically sourced and at the end of its life will biodegrade and give back to the environment. Most surfers are by their nature are environmentalists, as their playground is nature, so moving to zero waste products is very appealing.

But the uses for wool-reinforced plastic are a lot bigger than just surfboards. In fact, as Barron says, "the wool surfboard is only 'a drop in the ocean' of potential uses for wool composite materials in water sports and other products."

Fiberglass, or more properly Fiberglass reinforced plastic or FRP, is problematic for a number of reasons. The glass fibers can be dangerous if they are inhaled. As Barron notes in his patent application,

Fibreglass whilst giving some useful strength is not ideal. It is a man made material that is not from a sustainable source. There are also many safety considerations to its use. For example, the International Agency for Research on Cancer (IARC) has classified all synthetic mineral fibres (SMF) as being possibly carcinogenic to humans.

The plastic is usually a polyester resin made from fossil fuels. They are thermosetting resins that, once they set, cannot be recycled.

Barrett uses bioresins, some of which use soybean oil instead of fossil fuels and are really not much of an improvement. Another board maker, Fletcher Chouinard, says “the bio content of resins is tricky and we make sure that it’s not food crop derived, which is one of the biggest fallacies in the environmental / green movement, as soy and corn use far too much land, water and diesel to make sense as a petroleum alternative.” But there are others that are made from post industrial food waste that do not need crops to be grown and harvested. There are also new processes being developed that dissolve resin so that the fibers can be recovered and reused.

This is where it all gets really interesting: Barron has developed a material that could replace nasty old fibreglass in many applications.

Together with NZM [New Zealand Merino Company] I am working on several other concept designs including other water-based sports – wakeboards, skis, yachts and then there are other industries such as furniture, kitchens and even aircraft. So, while surfboards will only ever use a small amount of wool, the sky is the limit on where this technology might be used.

There are some who say that wool is not sustainable or ethical, and that raising livestock produces greenhouse gases and degrades land.Katherine has noted that "The biggest issue with wool is the methane emissions from burping sheep. An estimated 50 percent of wool’s carbon footprint comes from the sheep themselves, as opposed to other fabric industries whose larger emissions hail from the fabric production process. " There are others who say that certified organic wool is cruelty-free, that wool sequesters carbon, and that "the farming of wool with strong environmental practices can also restore and enhance the land." This is obviously a complex subject.

However, the idea of an FRP where the fibers are natural and renewable and held together by resins that are truly "bio" is very seductive.