AgResearch scientist unravels the science of carpets
For most of us it's just something we move around on each day without a thought. But when Steve McNeil looks at a carpet he sees a host of scientific possibilities.
In a career spanning 30 years specialising in wool and textiles, the AgResearch senior scientist has looked into how the design of carpet can affect the mobility of elderly or visually impaired people, how the carpets affect acoustics and absorb airborne contaminants, what resistance they offer to fire, and even how they can be used to improve plant growth.
In fact, McNeil's first role as a scientist just out of university was in applied chemistry relating to anti-static carpets.
"I think about the benefits of carpets when I see them, or see the lack of them," McNeil says.
"There are the issues of safety when moving around on them, and with wool carpets in particular, we know they improve indoor air quality by neutralising air contaminants such as formaldehyde and sulphur dioxide, which can be harmful. Wool carpets are also effective at absorbing noise – it's something you often don't notice until it's not there."
McNeil and a colleague experimented with a visual design of carpet made specifically for an elderly person, as compared against others carpets.
Subjects wearing face shields with a lens simulating the vision of a typical 80-year-old were observed at they walked across the different carpets, carrying a container filled with water so they had to concentrate on two tasks and couldn't see their feet.
"The result was that the specifically designed carpet, with a border pattern that was not cluttered by detail and gave the feeling of walking in a lane that guided the walker, and with clearly visible colours, was the easiest to navigate. It gave us a valuable insight into what design made life easier or more difficult for an elderly person, which could be important for independent living."
In another study, McNeil and colleagues tested the effectiveness of shredded wool carpet as a fertiliser – an area of interest given many consumers nowadays want to know that products can be recycled.
The shredded carpet was shown to act as a slow release fertiliser – increasing the dry matter yield of grass (dry matter is a measurement of the mass of something when completely dried) by as much as 80 per cent. It also had the effect of raising the level of essential elements such as nitrogen in the grass, as compared to unfertilised grass. This work encouraged other researchers to the study of the biodegradation of wool.
McNeil's work with textiles has also seen him explore the harmful effects of ultraviolet light (UV) and the potential for greater protection from clothing. He and his colleagues tested a range of organic and inorganic treatments on a lightweight knitted wool fabric to see how it affected the amount of light passing through the fabric.
One treatment, called Leucophor, raised the UV protection factor from below 15 to 50+. Importantly, this treatment held up when the fabric was washed.
McNeil has also demonstrated an alternative to using chemicals for removing the naturally occurring layer of fat on wool that repels water.
"We showed that the fat layer could be removed by ultrasound. When this layer is removed, new coatings such as those that prevent shrinkage of fabrics can be applied."
Having gained his Masters degree at the University of Canterbury and later his PhD from the University of New South Wales, McNeil cut his teeth as a scientist with the Wool Research Organisation of New Zealand (WRONZ), then moved to a WRONZ offshoot called Canesis, before Canesis was acquired and absorbed into AgResearch.
"Even though I grew up in Christchurch, we were on the edge of the town, and there were farms over the road. Sort of in between the city and the country. We would go and help the farmer milk his cows sometimes – back then it was called a town supply dairy farm. My father grew up in outback Queensland so he used to tell stories about drovers, stations and jackaroos. This gave me an interest in rural life."
"It's certainly made me appreciate the benefits and importance of what we are trying to achieve. While our textile team doesn't do `on-farm' work, we are dealing with textile products from New Zealand wool. So, if the textile factory here or overseas doubles its output of wool products, because of something we have developed, it will be doubling the amount of wool it buys from New Zealand."
While McNeil's career has always seen him focusing on the science behind wool and textiles, he feels like he has had a range of different jobs – such is the variety within his role.
"We are always bringing things in, like nanotechnology or artificial intelligence, to make better products, and that keeps the research challenging and interesting."