Bioplastics—where exactly are we?

The biennial Innovation Takes Root event was once again an ideal opportunity to check in on the progress of packaging that’s made from renewable resources.

Every two years NatureWorks, the world’s largest producer of polylactic acid (PLA), gathers together its partners and customers in Orlando, FL, for an event called Innovation Takes Root. Essentially it’s a biennial in-house convention of those who are stakeholders in the business of packaging made from renewable resources.

The fourth edition of Innovation Takes Root, held this Spring, was no different, with more than 300 additives and coatings suppliers, machinery manufacturers, compounders, converters, end-users, and brand owners gathered from as far afield as Europe and Asia for a two-day, multi-track, heady mix of presentations. It was all about ideas, challenges, processes, and development news about new performance applications. Also in the mix was no small amount of futurology and glimpses at long-lead-time research into emerging technological advances in bioplastics. Finally, at the end, it was all topped off by an end-note presentation by NatureWorks’ CEO Marc Verbruggen charting the way ahead. Here from the presentations are the main takeaways that will shape, or are already directly affecting, the bioplastics packaging sector.

The brand owner writes the checks
In packaging, while the consumer is king, it’s the brand owner who specifies the product and writes the checks. So any presentation that allows industry a peek into the check writers’ long-term thinking is bound to draw a full house.

This was the case when Nestlé, arguably the world’s largest Consumer Packaged Goods manufacturer, took the stage. Sokhna Gueye, Nestlé’s Packaging Environmental Sustainability Specialist, began by acknowledging the role packaging plays in food waste reduction, product protection, and contribution to sustainable development, as she outlined Nestlé’s Environmental Sustainability Policy.

As a global food giant, Nestlé is probably at the forefront of transparency and actionable policies that take the wider perspective of sustainability, including gender equality, rural development in the developing world, responsible sourcing, etc. Gueye presented and narrowed the global strategy down to the brand’s key packaging focus: Sustainability by Design, following a Life Cycle Analysis (LCA) approach, to ensure all packaging is optimised to use minimal adequate materials by weight and volume while maintaining product and environmental performance through to end-of-life.

“With end-of-life, we want to contribute to initiatives that help the recovery of used packaging and address littering. We aim to use recycled materials that have an environmental benefit and are appropriate, with a focus on paper, paperboard, corrugated, and plastic applications,” explained Gueye.

“We also want to lead the development and use of renewable materials,” she said, which brought her to bioplastics. But few in the audience were prepared for the uncomfortable questions she posed.

“For us bioplastics raise several questions, one of which is end-of-life compostability and biodegradability,” said Gueye. She then wondered if things like ease of compostability and minimized impact on the environment—fundamental to the whole bioplastics movement—are really and truly advanced by bioplastics. Even when sourced from sustainably managed resources, do bioplastics really address resource depletion and global warming when one takes into consideration the long-term impact on water use and agriculture?

Plain-speaking Gueye posed many rhetorical questions before delivering the Nestlé perspective: “Today there is limited availability of composting facilities. Even where they exist, compostable packaging is not necessarily accepted by the market. As a global brand, the great challenge is that we can’t put compostable material into markets and tell our consumers it is compostable, because that is not necessarily the reality at end of life in their country. If they don’t have the schemes or means to compost, we cannot claim the benefit.

“Even then, composting is not necessarily the most appropriate end-of-life option, compared to other options like recycling, direct fuel substitution, or incineration with energy recovery. Composting frequently brings less environmental benefits than some of these options.” Uncomfortable words for an audience for whom composting is a KSP (Key Selling Point). And she wasn’t finished.

“When compared to conventional plastics, bioplastics do have the potential to reduce greenhouse gas emissions and save on non-renewable energy use. But when we also look at the agricultural production side of the equation—fertilizer use, the impact of pesticides on animals, and water use—bioplastics mostly produce more greenhouse gases, not less.”

After letting that echo around a suddenly silenced room, she delivered the get-out-of-jail card by asserting that all is not lost. “What it means is that there is potential to improve in these categories by having better agricultural practices and by using alternative sources,” she said.

Gueye reiterated the importance of packaging material performance, suggesting areas the PLA industry should address: having adequate moisture barriers and exploring 3rd-generation bioplastics, which Gueye terms as “new bioplastics adapted to packaging applications derived from non-food sources such as wood, agricultural waste, drought resistant plants, and algae. The third-generation bioplastics are about enhanced performance compared to conventional materials and non-competition with food. This is what we are looking at for the long term.”

By the time Gueye was finished, her audience had little choice but to accept that no matter how many studies out there suggest that bioplastics do not compete with food crops, the fear that they do remains a key concern for brand owners such as Nestlé. That being the case, we can only wonder if Nestlé will be investing in bioplastics any time soon.

The confectionery view
Confectionery company Mars took a different approach, and has been in a four-year Research & Development program with Dutch producer of starch-based products Rodenburg Biopolymers to produce a bio-based film specifically for the Mars and Snickers chocolate product lines.

According to Thijs Rodenburg, CEO of Rodenburg Biopolymers, in the original concept specification, Mars was looking to switch to a bio-based packaging material delivering a lower carbon footprint than current packaging.

The new packaging material solution also had to be scalable into other industries—and had to be “sellable” into other applications within the groups’ SKUs to ensure there was an economy of scale amortizing the development costs and making the material affordable.

“Mars was looking for a type of bioplastics that was just not available in the market at the time,” explained Thijs Rodenburg. “The focus was to use a packaging material that is sustainable and uses 2nd generation feedstock that doesn’t compete with the food chain.”

Echoing Nestlé’s position, biodegradability and compostability was less of a priority because the company was concerned that consumers would not really understand what they really mean. Mars didn’t want consumers thinking that the new packaging material would just simply somehow dissolve into the environment, giving the impression that it could be casually thrown away.

The project took four years following the final specification sign-off through to the creation of a starch-based stable printable film that could be passed on to consumer research for feedback analysis.

The material base for the compound is a starch derived from waste potato peelings, thus satisfying the primary specification that “it present no competition in the food or animal feedstock chain.” The formula also contains “some” PLA, said Rodenburg, guardedly.

Taghleef, Mars’ Dubai-based packaging converter, was enlisted to manufacture the film at one of its existing BOPP lines in Europe. “Unfortunately, the compound did not perform as expected at the first trial—causing bubbles and folds in the webbing. At our second trial, we dried the compound, but that then led to it becoming sticky and blocking the drying process. Finally at our third attempt, we were able to produce a film that could be stretched to the required dimensions to fit the existing print and filling equipment.”

Austria-based converter Mondi was given the job of performing the final conversion. “Printing on the film was challenging,” said Rodenburg. “Initially they had problems with wrinkling in the film during the print process.” However, the project succeeded on the fourth attempt, and at full production speeds the line ran perfectly to produce wraps for both Mars and Snickers bars.

“The challenge,” said Rodenburg, “was to produce a completely new material which not only provided a lower carbon footprint and satisfied the barrier requirement that chocolate presents, but also to ensure that it would run on legacy production lines with no additional capital investment—and that we have achieved.”

A side bonus, discovered during the consumer feedback sessions, is that the new film has lower gloss and sheen when compared to the conventional packaging. Consumers saw that as a positive change that gave the packaged product a “more natural look and natural perception of the chocolate,” explained Rodenburg.

The new material, although already proven at commercial production speed and tested at retail in select locations, has yet to be launched into the European market, with no date currently finalized for a full-scale roll-out.

Coffee capsules go compostable
Italian coffee company Lavazza developed the world’s first single-serve espresso coffee capsule in 1989, and since then the single-serve coffee sector has seen steady growth, accelerating in the last seven to eight years.

Between 2012 and 2017, the global single-serve coffee market is expected to grow by 12%. That’s higher than the average coffee sales growth rate of 10%. In the US alone, the singe-serve coffee market has grown 319% since 2011, hitting US$4.6 billion in 2015.

The downside is that the coffee capsule is under mounting criticism that it generates a new and unnecessary level of packaging waste in a world attempting to reduce landfill. Yet the market sector’s exponential growth suggests consumers in general are not too bothered about the environmental impact.

“There is still a drive in consumption demand for single-serve coffee capsules because they are convenient and easy to operate,” said Dr. Fabio Osculati, Chief Technology Officer of Luigi Lavazza S.p.A. “This is especially true of espresso, which has a very specific brewing method requiring specific temperatures and pressure to provide the right quality. This is why people pay four and sometimes even seven times more for coffee capsules, because they are good products. Capsules also protect the coffee from oxidation, humidity, and leakage, offering a 24-month shelf life. Coffee capsules make consumers happy.”

Claudio Gemmiti, Senior VP Innovation & Strategic Growth of Canada’s largest roast and ground coffee producer, Club Coffee, then showcased his company’s solution to balance consumer demand with environmental issues: A 100% compostable capsule—the PurPod100.

The capsule comprises three main components: thermoformed ring, lid, and mesh. A blend of bio-resin and 20% coffee chaff reclaimed from the coffee roasting process forms a compostable thermoformed ring and the chaff helps accelerate the composting process. The lid is a compostable combination that uses a new compostable ink solution, while the mesh is made from a new bio-polymer formula and molding process.

The PurPod100 is BPI-certified (Biodegradable Products Institute) and experiences 96% disintegration in less than 84 days. According to Gemmiti, the solution offers two key benefits for the composting sector for the US market. It promotes growth of curbside/depot composting in the country, and it helps link composting to the food waste and household waste narrative, thus putting coffee back into the organic stream. Gemmiti summed it up this way: “PurPod100 reduces consumer ‘environmental guilt.’”

The barrier issue
One perceived shortcoming of PLA-based packaging is that it doesn’t have the best gas or moisture barrier properties. So Italy’s Metalvuoto has developed Oxaqua, a compostable and biodegradable bio-coating that brings high gas-barrier performance to any plastic film. This extends the packaging application possibilities for brand owners looking to switch to PLA-based packaging who had previously been held back by the material’s inadequate gas and water vapour barrier properties.

According to executive director Gianni Costanzo, Oxaqua has an ultra-high gas and aroma barrier that fulfills the ASTDM D3985 standard, as well as a high humidity resistance of up to 75% RH. In addition, it has excellent transparency.

This means that instead of using, for example, meat trays made of BOPET/PE/EVOH/PE layers and lidding film made of APET/PE/EVOH/PE layers, customers can now produce an all-polypropylene solution with a CPP Oxaqua + CPP tray and BOPP/Oxaqua/CPP top. Customers can also produce an all-polyester packaging solution with a special barrier APET bottom and PET Oxaqua/PET-Seal on APET top.

Metalvuoto has already found an application for Oxaqua—using it to create a packaging film can extend product shelf life up to one year, and enable shifts from fossil-based to bio-based packaging.

Developed in collaboration with NatureWorks and Taghleef, this packaging film is one-side coated and metallized with heat sealable performance, using a combination of a special metalization technique enhanced by a plasma activation system and Oxaqua barrier coating. With a total of three layers (metalization + Oxaqua coating + BOPLA core), the transparent film has an ultra high oxygen barrier and low water vapor permeability, while its sealing bond strength is more than 200g/inch.

The wrap-up
With questions about biodegradability and composting at the fore of many of the presentations, Natureworks CEO Verbruggen used his wrap-up presentation to redirect the delegates away from PLA’s “green credentials” to focus on the Three Ps of PLA biopolymer—Performance, Price, Preference—and share a vision for the future.

“The PLA industry and market has moved beyond the customer preference for a sustainable solution to one increasingly focused on performance, properties, and price,” Verbruggen told the delegates. “We didn’t develop PLA on the basis that we were going to be the green polymer. It was all about economics, and even with oil at $30 a barrel we remain competitive against conventional plastics. Ingeo was developed 15 years ago when oil was $20 a barrel and even then, we felt we could compete; we believed back then that we could make the economics work,” he explained.

According to Verbruggen, PLA is competitive from the perspective of both cost structure and chemical mapping in the rigid plastics sector compared with conventional plastics such as PS and PVC.

“As polystyrene depends on the price of oil, our cost structure is dependent on the price of corn, which is cheap, relatively speaking. If you look at corn futures, or for that matter sugar futures, the expectation is that the price of corn and sugars will remain low—that is very helpful in a market with plunging oil prices.”

According to Verbruggen, polystyrene sells in the U.S. market today for an average of $0.70 a pound. “At that price, PLA is cost competitive,” he said. “On the other hand, PET today sells in the range of $0.45/lb. Going head-to-head with a plastic priced at under $0.50/lb is not feasible for PLA. It’s as simple a that.

“Of course I would prefer oil to be at $100 a barrel, but that’s not today’s reality. Getting brands to transit into bioplastics would be easier if oil was $100 a barrel. In the past, when the oil price was high, we saw companies switching from polystyrene to PLA in the name of sustainability, where in reality it was all about the lower cost. Today that is far more difficult to do when you look at, for example, the price of PET versus PLA.”

Signalling an expansion beyond the packaging space, NatureWorks has been focusing more on performance chemicals in recent years, said Verbruggen: “If we think about styrene, for us it’s always been about competing against polystyrene; but ultimately styrene is a monomer that is used in a lot of different chemicals.

“In the last couple of years we realized that our world should not just be about being PLA the polymer. You can actually do a lot more things with our lactides monomer that we use to polymerize into PLA, just as one can do a lot more things with styrene than just making polystyrene. So if we look at ourselves not just as a polymer producer but also a monomer producer, suddenly new markets are opened such as surfactants, adhesives, solvents, and a lot of the much broader-based chemical markets.”

All of which means that the PLA scene should be an interesting one to watch in the coming years. PW

Trina Tan is Editor of PackWebasia.com, the news network out of Singapore for the Asian packaging community.

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