Packages and closures for packaging

Plastics – more than a hundred material variants Recycling – not necessarily for everything Mono-materiality – when technology outpaces legislation...

One form of plastic isn’t the same as another, which is something not everybody is aware of.
What is still surprising to some is the fact that tires are plastic, that Plexiglass is plastic, anti-stress ball is plastic, fleece is plastic and most of the car’s interior is also plastic... and we're not talking about a Trabant.  Even in the case of food and cosmetics packaging, it seems that everything here is plastic and, basically, one and the same form.
However, it’s not so obvious, because beverage bottles are PET, but bottles for e.g. nail varnish remover are mostly HDPE. Yogurt can be packaged in PP, i.e. polypropylene, whereas take-out food in polystyrene (PS).
We may also have polyvinyl chloride (PVC), whose reputation is deteriorating due to the fact that it emits highly toxic substances into the atmosphere when exposed to high temperatures.
Plastics comprise a total of more than 100 different materials, which can additionally be combined into composites or laminates, added reinforcing substances, dyed, enriched or made more flexible, non-flammable or UV-resistant.

Each plastic differs in terms of its chemical composition and properties. Manufacturers of FMCG try to match the material to the product being packaged, answering a series of questions, such as what kind of protection is needed, how long and under what conditions, as well as, crucially, what kind of product will be stored. How to balance the price of packaging, and, at the same time, be able to demonstrate care for the environment.

One packaging – a complete overview of the plastic industry offer!
There are situations in which one plastic isn’t enough! Even in small but technologically complex products, such as lotion pumps or mist sprayers, we’ll find several types of plastic. Even a plastic bag for, let's say, a supply of soap or frozen food usually consists of at least two types of plastic, and if the label is added, three.
Although closures can be "taken apart", and you can see that there are small parts that differ at first glance; for example, the seal is elastic, the head is rigid and relatively solid, and the tube is flexible. However, in the case of the film from which the soap bag is made of, we won't know without proper laboratory instruments what's inside... And  inside there are at least three layers of PET with PE, PA with PE, and sometimes paper is added. These are weldable layers and barrier layers plus, possibly, decorative ones. All of them form laminate, that is, different plastics tightly put or glued together to form a unity.
And can’t it be simpler? …we could ask…
Well, it can, but it will be more difficult and expensive!
We’ll discuss it later in the text.

Consequently, plastics differ from one another in terms of their physical and chemical properties, and ultimately in how they may end up and in what company.

Wish-cycling, i.e. (theoretically) everything can be recycled!
The so often mentioned recycling is simple and not simple at the same time.
Most plastics can be recycled.
You can do a lot and efficiently in laboratory conditions, but not so much in industrial ones.
In this case, what’s the most important is the profitability of the entire process - in financial, but also environmental terms, to avoid a situation in which we waste more energy and water to recover the material than to produce new one.
One of the most difficult stages is waste segregation. It has been partly transferred to consumers. The pre-separated waste fractions go to sorting plants, where mechanical and optical sorters as well as the human eye separate the waste, and segregate it for further processing.
What can be recycled?
The most rewarding material when it comes to sorting and processing is PET.
On the other hand, HDPE is the most valuable one. The best example is water bottles (PET) and caps from these bottles (HDPE), which, when collected selectively, are the most commonly eliminated waste from our landscape.  

Why only that, if the slogan that any plastic can be recycled has been promoted since the 1970s? Why do we suddenly more and more often hear that it’s impossible, that we produce too much waste, and that plastic poses a threat to us?
What’s the reason for that boom?
Until 2017, China was the "rubbish dump" of Europe and the USA, whereas, we as citizens of the developed world, were thus reassured that actually everything is reused in a new form. Container ships sailed out of European ports with trash, and in return they left certificates that it had been recycled.
However, when China began to look for the causes of smog in its cities, it realized that the garbage collected from various continents was only partially recycled - the most valuable one - and the rest was burned in an uncontrolled manner, thus poisoning the air, causing asthma, cancer and endocrinological diseases. The Chinese authorities, famous for their ability to count money, put the earnings flowing from this form of recycling on one scale and the health of citizens, and cynically speaking, citizens as workforce, on the other.
Those calculations demonstrated that it was clean air and a healthy citizen are more valuable than junk-dollars.
Bringing waste from everywhere has been banned!
Europe and the USA faced a huge problem finding a solution for their own waste, because at the time China was collecting it, no one on the two continents was developing the recycling infrastructure that could process 100% of the waste produced.
For the past six years, we’ve been observing very nervous legislative activity aimed at reducing the waste generated (ineffective!), expanding the infrastructure that recycles waste (ineffective!), looking for alternative packaging materials (marginal!).
The only thing the authorities have managed to do effectively was to impose more restrictions, exclusions and requirements, acting from behind a desk, without confronting the reality, which is always dangerous.

In real life, we recycle a small group of waste.
Furthermore, few people are aware of the fact that plastic as such can’t end up being recycled. If the entire "yellow bag" was thrown in, we wouldn’t get valuable recyclate, but rather only slush without the possibility of creating anything new out of it.
You can recycle identical materials with each other, i.e. the above-mentioned PET bottles as one stream, HDPE caps as a separate one. Different materials require different conditions, and different properties are expected from them.
On the other hand, there are plastics that do like each other in recycling, provided that the amount of one of them is small in relation to the majority of the other. And if a small amount of PP gets into the HDPE stream then nothing bad will happen, but if something was to fall into the PET, then the new bottle could be leaky, delaminating or inflexible.
What would really make recyclers' life easier would be to limit the production of packaging to the use of one plastic with perhaps a marginal addition of another one that can co-exist in the recycling process.

And that's the moment when mono-materiality comes into play!
What is it, and why can it be justified from the economic and environmental point of view?

Eco-designing of packaging with consideration given to restrictions regarding polymer amount is quite an improvement for sorting plants when it comes to directing waste to the appropriate recycling stream.
Airless face cream packaging made of polypropylene with the addition of a metal spring, which will be removed by a magnet, gives plastic a chance for the second life. If it was packaging which contains, for example, six different interconnected plastics, the hope that someone at the sorting plant would separate the small parts from one another is illusory.
The same is the case with film laminate. If we put together three layers of polypropylene of different thickness, we can hope that the sorter will catch it, and return it to circulation.
Products marked with the number 5 (PP), and, in addition, with coded information in the label about the material composition, offer a chance for recovering the plastic.
The eco-design requires extensive knowledge of materials. It also requires knowledge of sorting plant operation schemes, the ability to code plastic compositions and knowledge of what can be processed.
Packaging that is slimmed down too much, even if it’s made of monomaterials, can be destructive to the sorting plant. Thin plastic bags stick to shredding machines, thus blocking the entire process and increasing its costs due to cleaning and stoppages.
Quality packaging made of a single material, without dark coloring or printed enrichments, is one way to keep packaging in circulation in an environmentally friendly way.
Quality food packaging can be used to produce building materials, pipes, cable casings, without which we cannot imagine our cities running. It’s also rarely taken into account in the context of plastics. Plastic has been the foundation of our existence since the 1950s. It’s necessary to make up for the systemic negligence resulting from shifting responsibility for cleaning up waste to others.
We look forward to the development and popularization of chemical recycling, but also heat recovery.
It's probably high time for proponents of the circular economy to come to terms with the fact that we won't process all waste, and that some of it, instead of lying in landfills, should be incinerated under controlled conditions.
As the cosmetics industry, we should have up-to-date knowledge of which materials are actually recycled in our region, and take it into account when planning the packaging.
If PET is recycled, let's focus on lotion and shampoo bottles made of that plastic. If it’s HDPE, let’s ask suppliers for packaging made of that material.
Alternatives can include glass or aluminum, which have many disadvantages, but also advantages.
In certain situation, they may prove to be a better solution than multi-material plastic.