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.
APAC Sustainability Director, Packaging and Specialty Plastics
Dow
Published Jun 7, 2022 8am EDT / 5am PDT / 1pm BST / 2pm CEST