Rather than focus solely on plastic alternatives, we must consider the full lifecycle of materials to see the benefits of circularity. Three technologies are surfacing as viable solutions to increase plastic’s circularity with low-carbon performance at the core.
The cotton tote bag, a seemingly sustainable alternative to plastic or paper bags, actually poses a little-known sustainability challenge: It needs to be used 20,000 times to offset its overall impact of production, according to Denmark’s Ministry of Environment and Food. That means using the same cotton tote bag every day for 54 years.
Despite consumer demand for alternative materials for plastic packaging — from metal and glass to paper and cotton — these options are not always the better solutions.
A study by Tsinghua University in Beijing, my hometown, found that paper bags — viewed as a more sustainable packaging material than plastic — resulted in the highest comprehensive environmental impact among five analyzed materials in China. Through a life cycle assessment — which accounted for all stages between raw material extraction and waste disposal — Tsinghua evaluated a range of environmental factors including air pollution, water pollution and resource depletion. The number of organic pollutants produced throughout the lifecycle of a paper bag was determined to be 16.4 times that of a high-density polyethylene (PE) plastic shopping bag.
To avoid creating upstream or downstream environmental impacts by implementing siloed fixes, we must consider the full lifecycle of certain materials to see the benefits of circularity. At Dow, we believe plastic is too valuable a material to be disregarded in the pursuit of sustainable solutions. Instead of solely pursuing non-plastic alternatives, we must apply material science to reduce the impact of plastic on the environment, while maintaining the material’s low weight and lesser energy consumption.
Taking a lifecycle view, three technologies are surfacing as viable solutions to increase plastic’s circularity with low-carbon performance at the core: mono-materials, compatibilizers and bio-based materials.
Simplifying with mono-materials
While all polyethylene can technically be recycled, the process of layering materials to create a finished product adds a complexity not suited for most traditional mechanical recycling systems. When you try to melt down the packaging to make it into something new, it can’t be done; the polymers separate like oil and water.
By growing the market for mono-materials — products composed of a single type of material — we can deliver packaging solutions that are fully recyclable from the moment they are put in the bin.
In China, for instance, Dow partnered with Liby — a leading laundry brand — to re-invent its detergent pouches for circularity. Enabled by Dow’s technology, Liby’s recyclable packaging earned the first “Double E” (easy-to-collect and easy-to-recycle) label in China, which helps consumers distinguish recyclable packaging.
Mono-materials are often disregarded in favor of multi-materials, which are perceived to offer added quality given they can accommodate everything from flexibility to branding applications. Yet, the Tsinghua study found that if all plastic packaging consumed per year in China were replaced with packaging made from other materials that provide the same function, overall life cycle environmental impact would increase by 2.3 times.
Consumer demand for sustainable packaging has also taken off in recent years. A 2022 survey by Innova Market Insights found 23 percent of consumers “strongly agree” and 42 percent “agree” that they would be willing to switch their usual brand for a brand with more environmentally sustainable packaging.
We now have the tools and innovative approaches to leverage mono-materials to produce the same high-performance packaging benefits, now with greater recycling potential.
Making opposites attract
When mono-materials aren’t an option, innovators in the materials space are also working to develop compatibilizers to allow for the reuse of blended materials. Compatibilizers are the addition of a substance to a blend of polymers to stabilize it — and they play an essential role in solving for recycling.
Dow has developed a special compatibilizer called RETAIN™ that helps a plastic package break down evenly across layers and enables the packaging to be recycled and recreated into a new plastic material.
Working in partnership with Kashi’s Bear Naked brand at Pack Studios, Dow’s innovation lab, we designed a new sustainable product pouch using our RecycleReady and RETAIN™ polymer modifier technologies. A revolutionary, non-laminated standup pouch design provided recycling solutions that traditional lamination could not — and within existing recycling streams.
Through material science, we can innovate outside the box, so to speak — evolving our understanding of how resources can work together for more sustainable solutions.
Downshifting fossil fuels
Bio-based PE resin performs with the same quality as fossil fuel-based PE, but with a lower carbon footprint at both beginning-of-life and end-of-life for packaging.
Creative thinking, even within the bio-based category, is required to avoid competing with the human food system. However, food waste and non-edible renewable sources have proven valuable as sustainable feedstocks.
In a step toward viable bio-based alternatives, Dow developed AFFINITY™ RE technology, which uses renewable feedstocks such as bio-naphtha from tall oil — a byproduct of paper pulp production that’s sourced in sustainably managed forests. Exploring the ways in which renewable waste can take on new life will be a critical path to moving the needle on waste reduction overall.
The path forward
Sustainability is not always intuitive; and there is no silver bullet for a circular economy. However, investments in science and a willingness to explore the non-traditional can put us on a path where future generations can make educated choices for the most sustainable products possible.
To learn more about the plastic packaging situation in China — including policies, environmental impact and product solutions — read the Tsinghua University study here.