When it comes to material science, the smallest details are inseparable from the big picture. In this field, adjusting the structure of a molecule by a single atom can completely change the properties of a material. Fortunately, people like Martin Settle thrive when unpicking these minute details that others might miss.
Martin, recently named among the first group of speakers for the renowned Packaging Innovations & Empack conference agenda in February, brings a wealth of knowledge to the discussion of material science in packaging. With a clear-eyed focus on sustainability and practical applications, he’s set to address critical challenges in the field, shedding light on the complex balancing act required to develop sustainable, commercially viable packaging solutions.
“People often overlook the critical role material science plays in packaging development,” he tells Packaging Innovations. “The right material can make or break a product. For instance, I could design a bottle made entirely from 100% recycled content that is chemically recyclable without limit, but the reality is that no one will pay for it.
“I can tell you that we have materials that could be used tomorrow to make sustainable products, but you wouldn’t buy them because they’d cost too much. That’s the real issue.”
As the Senior Manager of Polymer Science in Sustainability and Packaging at health, hygiene, and nutrition giant Reckitt – the company behind household name brands like Nurofen, Dettol, and Vanish - this demonstrates the kind of problems packaging designers have to grapple with daily. And, as Martin says, anyone offering easy solutions to those problems should be viewed with scepticism.
“There’s a lot of misinformation and greenwashing around the industry that needs to be debunked. We should be evaluating every solution with a focus on whether it provides true material reduction, whether it actually reduces energy consumption - not just in manufacturing, but also in transport and sourcing raw materials.
“Is it a renewable resource? Can it be replenished? Can you plant trees to replace the ones used for paper production? Is there a recyclable component that can be added to reduce environmental impact? For example, it takes about 14 trees to produce a tonne of paper, depending on the grade. If we switched everything to paper, we’d need a whole new planet. It’s just not practical. And remember, trees don’t grow in six weeks - it takes at least three to five years for them to mature, and we don’t have enough land space. It's as simple as that.
“The technology exists - some of it’s in its infancy, some is limited, and paper is a prime example of that. The lack of understanding about these limitations is the main problem.”
Everything in its place
Martin is careful to qualify his comments on paper – just as paper isn’t the solution to every problem, there are just as many applications where it works just as well. “We need a clear understanding of where these materials fit, how they’re used, and their practical limits. If I had to wrap a chocolate bar, I could put it in paper tomorrow—no problem. A cereal bar could also be in paper, but that paper would need to be coated with plastic. If it’s a pouch for liquid hand soap? Not a chance.”
There are no heroes and villains in this story – just complex compromises. That applies to exciting new innovations as much as it does to the existing technologies that the industry is working hard to improve. “Take biopolymers,” he says. “They have their benefits, but to a certain point. For Europe, they’re a nightmare because Europe and the UK are taxed based on recyclability and recycled content. Unless a biopolymer can be recycled through mainstream processes, it’s not as useful.
“We’ve evaluated them all, and there are issues. PLA, for instance, is often praised, but it contaminates the waste stream. PVOH and PVA are alternatives, but they’re still polymers, regardless of their feedstock. What we’re finding is that biopolymers are great at the front end but problematic at the back end. Only certain types really work well, and they are good for replacing plastics in specific applications, like components within components - coating trays, or coatings on boxes, for example. They work well in these cases because they get washed away in the recycling process at paper mills, which use chemicals like alcohol and acids to break things down.
“In my opinion, biopolymers have their place, but only for very specific products that can’t be recycled.”
A solution for every market
At this point, it’s easy to start questioning what the ideal solution actually is – or if it even exists at all. But as Martin argues, looking for one magic bullet solution is the wrong approach. “I always tell my team, don’t approach everything with blinkers on. Look at it in terms of what is the best material for the specific product, the solution, and the market you’re targeting because not everything will work in every market. It's as simple as that.
“So, we have to balance all these factors. You have to keep an open mind, with no preconceptions, because there’s always something new and unexpected. We’ve even seen old technologies like casein [milk protein-derived polymers first introduced in the early 1900s] make a comeback because it’s a natural source that can replace synthetic polymers in glues for laminating bottles, labels, etc.
“We also look at polymers derived from other natural sources, like chitosan, which is made from crustacean shells, the second most abundant polymer source in the world. A company in Scotland has developed a process to turn it into a usable material that’s now going commercial. It’s great, but the price is still high, and everyone’s testing to see where it could be used.”
Does Martin think this is likely? “It’s a promising story if used in the right way. The first thing we would ask any innovator is, ‘What’s the end-of-life solution for this material?’ If it creates a waste profile we can’t manage, we’re not interested. You have to think about both the business needs and the environmental impact. It’s great if a startup offers something better than what we have now, but if the end-of-life solution doesn’t align, there’s an imbalance, and the material’s application becomes limited. This is why, while many bio-based materials may look fantastic, the key question is: what’s the end of life?”
A painstaking process of innovation
Sometimes, working through these issues can take years of R&D – a rigorous process that can yield unexpected results. “From every hundred ideas we evaluate, we might move five to ten forward for testing, and out of those, perhaps only three or four will survive over a five-year period,” says Martin.
“We’ve had plastic springs on the agenda for about two years. We currently use metal springs in pumps and triggers. You can compress them and they’ll return to their original shape a minimum of 2,000 times before losing their compression strain. Plastic springs, on the other hand, typically last only 250 compressions. For some people, that reduced lifespan is acceptable. However, it can be a nightmare.
“For instance, with hand soap, you get about 160 uses from the pump. If you really fill it, that adds another 160 uses, but the spring starts to lose its power after that. If it’s a plastic spring, it will wear out quickly. So, we had to design a polymer spring robust enough to handle multiple refills—ideally five or six—while ensuring it can last up to 2,000 uses. That’s a pure polymer engineering challenge.
“We’ve even reached out to manufacturers of plastic springs used in airplane landing gear due to the technical complexity involved. Then there’s the issue of testing. When we started incorporating post-consumer recycled (PCR) materials, we found that people often thought, ‘Oh, we can just throw in some PCR, and it’ll be fine.’ But that’s not true. Adding PCR changes the material characteristics, affecting how the plastic flows and melts at different rates and formulas.”
As Martin explains, these frequent reality checks are needed to ensure packaging can still fulfill its core purpose – protecting products and, ultimately, consumers. “As part of my role, I step in to ask, ‘Have we tested this to see if it’s viable? Can we blow a bottle, cup, or spoon out of it? Will it pose any risks to the consumer?’ It could be the most sustainable product in the world, but if it has even one negative impact on the consumer, it’s a problem.
“My team and I look at these materials and come up with innovative ideas. We will test everything – absolutely everything. We evaluate physical characteristics, material properties, and how they interact with the product. We assess whether they can withstand transportation and e-commerce transit, the impacts on shelf life, and any risks to the consumer. All of these factors are encapsulated in what we do.
“This reality is why our work encompasses material science, engineering, consumer science, and commercial strategies. All of these elements combine to give us a clearer picture of what’s feasible.”
As a relentlessly forward-thinking industry, this kind of pragmatism can be a bitter pill to swallow. However, just as the hottest fires make the strongest steel, the most painstaking development processes often result in the best packaging. Ideas and inspiration are vital ingredients – but reality remains the ultimate test. Martin Settle’s eagerly anticipated appearance at the Packaging Innovations & Empack 2025 will dive deeper into this very challenge, offering unique insights from his extensive experience in polymer science and sustainable packaging. His participation promises to shed light on the practicalities and trade-offs essential for meaningful progress in sustainable materials.