Biodegradation-boosting synthetics
End-of-life scenarios are important when assessing a product’s impacts, but they are not an easy sell. This is one of many challenges the makers of synthetics yarns enhanced with biodegradation-accelerating additives face. As concerns regarding the permanence of plastic grow, so does demand for these materials that are engineered to leave no trace.
The positive attributes of synthetic fibres include durability, recyclability and various other functional properties. Active and outdoor apparel relies on hard-wearing synthetic yarns to deliver lasting performance. These garments will not break down, whatever uses, conditions or environments they are subjected to. However, synthetics, in essence plastics, are no longer viewed as a miracle material but as a source of pollution of such proportions that some now say we are living in the Plasticene Age. Synthetic yarns enhanced with an additive that accelerates biodegradation could be a solution to mitigate the persistence of these materials in nature.
Synthetic yarns owe their inherent durability to their strong molecular bonds. Engineering them to break down could thus seem counter-intuitive. The substances added to these so-called biodegradable synthetics are said to make them more accessible to microorganisms that can convert polymers back into their basic elements. This is a process that, in a well-managed landfill, will produce biogas and biomass.
To accelerate biodegradation sounds like a good idea, but how fast is ‘accelerated’? These manmade fibres are engineered to break down in a reasonable amount of time; it is still slow, but faster than for a standard petrochemical-based yarn. A sportswear item made from one of the many enhanced synthetics on the market will most likely still take decades to disintegrate in a landfill, but not centuries. This is pretty much the main claim that providers of these innovative materials can make. This new class of synthetics comes with a long list of caveats that makes it tricky to spin a positive marketing message. The key catch is that no reference to biodegradation can be made when describing the features of textiles, apparel, or even plastics for that matter. This article will not comply with that condition, but the term will never be found on any hang tag. The world of compostable or biodegradable plastics is highly regulated, and the trend today is not to lighten or lessen any restrictions.
A thriving market
Despite the restrictions imposed on marketing claims, and the complexity of describing how materials break down in a given situation – freshwater, salt water, soil, landfill, open environment – the market for synthetic yarns engineered to speed up biodegradation is surprisingly buoyant.
A division of Solvay in Brazil introduced what is possibly the first such synthetic polymer at ITMA in 2014 with Amni Soul Eco, a polyamide 6.6. Well aware of the novelty and specificity of this new yarn, the chemicals company headquartered in Belgium was careful to indicate that Amni Soul Eco would biodegrade, if correctly disposed of in an anaerobic landfill, in about five years. It is now one of several eco-nylons made by Italian nylon producer Fulgar. In 2021, Israel-based Nilit ushered in Sensil BioCare, also a polyamide 6.6, “enhanced with a special technology that helps lessen the persistence of synthetic waste in oceans and landfills.” Note the absence of the B-word.
Japanese fibre producer Asahi Kasei’s biodegradable elastane, Roica V550, came to market in 2017, and was touted as the first to receive Cradle-to-Cradle Material Health Gold Level certification. It also carries a Hohenstein Environment Compatibility Certification confirming that it does not release harmful substances in the environment when it breaks down.
CiCLO Technology was officially launched that same year as a textiles ingredient for polyester by Intrinsic Textiles Group (ITG), a start-up based in the Bay Area of San Francisco. Since then, it has formed a joint-venture, Intrinsic Advanced Materials (IAM), with an industrial partner, Parkdale Mills. The specially formulated additive was initially developed for the company’s own use in workwear programs, Andrea Ferris, co-founder and CEO, tells WSA.
Insulation specialist Primaloft introduced a biodegradable filler in 2018 presented as a market first as it is made from polyester that is both recycled and biodegradable. Advansa, based in Germany, one the newest members of this club, has recently launched Remotion with its Indonesian partner Asia Pacific Fibers (see separate article, page 34). Remotion is a polyester yarn made, in one version, from recycled ocean-bound plastic bottles and enhanced with “built-in biodegradability”. The partners take care to note that biodegradation rates strongly depend on individual factors like temperature, moisture, surface area and exposure of the final article in the soil, the types of microorganisms present in the soil, and many more.
Antex has also integrated a biodegradation accelerator in its range of Yarnaway synthetics. It has already been introduced in its polyester offering, but may in time be added to the company’s PBT, PA 6 and PA 66, as well as polypropylene offerings. The additive the Spanish filament and fibre producer has chosen to use is EcoOne. Made by US-based Ecologic, this is described as an “organic additive that enhances the biodegradation process through a series of chemical and biological processes when disposed of in a biologically active landfill”. The polyester yarn was in development for a year, the time needed to test different types of yarns, Antex innovation and sustainability director, Marta Molist, tells WSA. “We tested the biodegradation rates of virgin and recycled polymers, as well as solution-dyed yarns, and have, each time, compared samples made with and without the additive,” she says. EcoOne-enhanced textiles were found to biodegrade by almost 90% in 1,000 days. This, she points out, is much faster than conventional polyester.
In 2020, Cocona Inc, based in Boulder, Colorado, the maker of thermoregulating textile technology 37.5, took the bold move to reformulate its entire range of fibres and yarns so as to feature accelerated biodegradation, at no added cost. The additive it uses is supplied by US-based Biosphere, which claims that its solution works faster than other products of this type, as it “allows the microbes in both aerobic and anaerobic environments to consume plastic from deep within and not just on the surface”. The decision to choose Biosphere “is the result of looking at different options to accelerate biodegradability and years of research to make a difference at the end-of-life phase for products made from 37.5,” says Cocona president, Blair Kanis. She adds: “there is a general sentiment, across the industry, to address issues with synthetics at the beginning and end-of-life stages.” Lacking a global infrastructure for the recycling of apparel, the company postulates that most textile products will, for the time being, continue to end up in landfill or be incinerated.
As this inventory shows, brands can now choose from a wide array of synthetic yarns engineered to leave little or no trace in a well managed landfill. Suppliers, as we have seen, proceed with caution in the claims they make, and it is safe to say that few brands are promoting this feature when marketing their products. Biodegradable properties, like any new technology, will take time to make an impression on the market, says Concept III founder, David Parkes. Despite some scepticism early on, he says “demand is now quite strong”. He is a big fan of IAM’s CiCLO Technology, noting that the innovative company never lost momentum, and that its yarn has “no negatives”. Concept III will be introducing a novel wool insulation made from a sliver knit that uses CiCLO as a backing yarn at Performance Days in October. Making sherpa and fleece products with the yarn is also, he notes, a way to reduce the impact of fibre shedding, and useful in the US market where discarded clothing tends to be landfilled.
But biodegradability, says Mr Parkes, should not be considered a marketing pitch but rather a function. “Performance apparel brands, and the industry as a whole, have a responsibility to develop products that offer both performance and sustainability. We need fabrics that not only perform but also go one step further and this includes biodegradability.”
CiCLO polyester and nylon are now produced by 50 or so fibre and yarn manufacturers, Andrea Ferris tells WSA. IAM works closely with its partners. A sample from every production lot is tested to certify the presence of the additive at the correct dosage. Though the technology is partially owned by Parkdale Mills, CiCLO fibre and yarns are widely available globally and beyond Parkdale’s distribution, she says. “Exclusivity arrangements can be contrary to IAM’s mission of making the greatest impact towards reducing the microplastic pollution caused by synthetic textiles.”
The company, she adds, takes a conservative approach to consumer claims. “We never make any claim as to precisely how fast a textile with CiCLO technology will biodegrade; we claim ‘a reduction of microplastic pollution’ with no guaranteed timeframe. Any innovation capable of mitigating fibre shedding is great. But she adds: “A synthetic yarn will shed microfibres throughout its life and there will always be some leakage into nature. Our message is that if you have to use polyester or polyamide and there is no alternative with the same performance and durability properties, choose a solution that will allow it to biodegrade.”
A better solution
There are, in many technical markets, no alternatives to synthetics, agrees Marta Molist, at Antex. “A car seat made from cotton will not last as long as a polyester one, and durability is a key factor in sustainability.” With regards to the broader issue of microplastic pollution, she says that Yarnaway has been tested in marine water, where it will also biodegrade but at a slower rate than in landfills. “We cannot consider this as the definitive solution for microfibres, but because they biodegrade in marine water, the time that they will be present in the seas will be shorter than normal synthetic microfibres, so the probability that they interfere with sea flora and fauna is much lower,” she says.
Andrea Ferris, at CiCLO, shares this point of view: “What we are talking about is the biodegradation of plastic pollution in uncontrolled natural environments. Microfibres are transient and certain conditions need to be met for anything that is inherently biodegradable to biodegrade: it requires moisture and access to microbes for extended periods of time. These conditions are not unique to our technology. Cotton will break down more readily than CiCLO fibres, but it needs those same conditions. We study the rate of biodegradation of CiCLO polyester and nylon using ASTM and ISO tests, simulating environments where these conditions are met and where microfibres are prolific, including wastewater sludge, soil and sea water. CiCLO technology enables polyester and nylon to fully biodegrade, leaving behind only natural elements, and this is proven by multiple third-party lab studies. However, we are not claiming that CiCLO ‘eliminates’ microfibre pollution because we cannot control where pollution ends up. We are saying that less microplastic pollution is better than more.”
About blends and trimming
Designing an item of clothing made from a synthetic fibre engineered to speed up biodegradation immediately raises the question of fibre blends and trimming. Suppliers, when questioned, pose few if any limits. Fabric manufacturers tend to develop these synthetics in blends with cotton or wool, whose biodegradability is rarely disputed. “A garment will have trimmings, zippers, labels, and so on,” notes Blair Kanis at Cocona. This confirms it is “a journey” and that it will not be easy to market a product as being made from 100% biodegradable components.
Other properties often promoted in performance wear, such as antibacterial functions, may slow down the biodegradation process, notes Marta Molist, at Antex. IAM recommends that brands using CiCLO choose Oekotex, bluesign or Cradle-to-Cradle certified chemicals. “While we cannot make a sweeping generalisation that all dyes will biodegrade, we do see dyestuff biodegrade in our studies,” says Ms Ferris. Ms Molist agrees but points out that full biodegradability may not be possible due to the presence of additives such as titanium dioxide or flame-retardants. “They constitute a minute portion of the yarn, usually less than 0.5%. Bacteria could well digest the remaining content,” she says. Likewise, it is not a good idea to coat a fabric “with a non-biodegradable plastic substance that blocks microbes from accessing the fabric if it is being created with the intent to biodegrade at end of life,” says Ms Ferris. She believes that biodegradable laminates will be available in time.
One clearly positive attribute of these modified yarns is that they do not interfere with the recyclability of the textiles, says Ms Molist, who insists that this would be the optimal solution. All suppliers of biodegradable synthetics agree that recycling is the preferred end-of-life scenario. While there is no easy solution to offsetting the permanence of plastic in active and outdoor wear yet, synthetics engineered to leave little-to-no trace offer a best-case solution, pending the development of more circular end-of-life scenarios for performance apparel.
Surfwear brand Billabong has chosen CiCLO Technology for its Recycler range of boardshorts.
CREDIT: Billabong
