The consequences of plastic consumption are omnipresent: On the one hand, there is the visible plastic waste that mankind leaves behind in nature - with all its terrible consequences. On the other hand, plastics decompose over time, creating microplastics - plastic particles between 1,000 nanometers and 5 millimeters in size - which also enter the food chain. Sustainable alternatives are in demand - we give you an overview of the developments here.
Sustainable plastics - not a new idea
As specialists in sustainable packaging and uncomplicated packaging solutions for a wide variety of needs, we are naturally concerned with this major topic: sustainable plastics that help our environment.
But this necessary trend is by no means as new as you might think: bioplastics were already being produced in the USA around 1870! At that time, cellulose was used as the starting material for thermoplastics. The aim was to develop a new material for billiard balls, which were traditionally made of ivory at the time.
Now this bioplastic, celluloid, proved to be quite useful, so that the area of application was extended to include toys, spectacle frames and other products. As early as 1897, a further development of bioplastic supplemented the portfolio, using milk protein as the starting material.
This process has proven its worth to this day: Although radio housings are no longer made from it, you may still have fountain pens and knitting needles made from milk protein in use today.
Inform in our blog post! We use sustainable plastics, for example, in our pouch packaging or plastic shipping bags. |
The big turnaround: petroleum-based plastics - great potential, lower costs
With the development of petroleum-based plastics, bioplastics received much cheaper competition in the first half of the 20th century: polyamide, acrylic and polystyrene were the first alternatives; since the 1950s, polyethylene and polypropylene were added. The more cost-intensive bioplastics no longer stood a chance against these plastics - which were made from petroleum, which was cheap at the time, and had many uses. But these materials are not the optimal solution for several reasons.
On the one hand, costs play a role: the price of crude oil has risen, but above all, increasingly stringent environmental regulations apply, which in serious cases also entail high fines. On the other hand, environmental protection plays the main role, which takes account of social pressure: Natural and finite resources are to be used responsibly. In many areas, industry is facing a major challenge here, the mastering of which will determine not least its future viability.
In principle, two paths open up:
- A functioning circular economy should ensure the reuse of natural raw materials that have already been processed.
- New plastics are expected to provide the answer to the pressing problems of our time.
It's obvious that we as packaging professionals are keeping a close eye on current developments - especially sustainable plastics. Because one thing is also a fact: plastics have such convenient properties, such as the enormous variety of possible uses, durability and stability, that they cannot be easily replaced by other natural materials. So where is the journey heading in terms of sustainable plastics?
Biobased and biodegradable plastics: What's the difference?
Currently, we see two basic trends that we would like to explain to you in more detail:
These plastics are created either partially or completely from renewable raw materials. You may have heard of polyactides or polylactic acids (PLA) or polyhydroxyalkanoates or polyhydroxy fatty acids (PHA). While the former are synthetic polymers belonging to the polyesters and composed of numerous lactic acid molecules, PHAs are naturally occurring, linear and water-insoluble biopolyesters. These are formed by bacteria and are biodegradable.
In addition, there are the polymers PP, PE and PA, which are produced from renewable raw materials and have long since been able to establish themselves primarily in the packaging industry - but not beyond that. The properties of these plastics are not (yet) sufficient for other technical applications. However, further innovative developments can be expected here, opening up exciting prospects.
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bio-based |
recyclable |
Biodegradable |
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The material consists entirely or to a certain extent of renewable raw materials. In addition to cellophane or rubber, these also include PLA and PHA as well as bio-PE or bio-PET. |
Plastics are recyclable if they can be recycled or reprocessed. For efficient recycling, the materials must be separated by type as far as possible. The plastics can then be shredded and reshaped by heating, for example. |
With the help of microorganisms, such plastics can be decomposed, leaving water, CO2, methane and biomass. For certification, there are set standards that specify certain standards and conditions for the degradation process and the final product. |
The boundaries between biobased and biodegradable plastics
Classification is not so easy, so let's look at the general definitions first:
Bioplastic
Accordingly, a plastic may be called a bioplastic, bioplastic or biobased plastic if it is produced on the basis of renewable raw materials. It does not therefore have to be biodegradable.
Accordingly, polyactide acides (PLA) are primarily used today. The basis is formed by lactic acids, which are obtained from the starch of sugar cane, potatoes or corn. You are certainly familiar with articles made of PLA, such as waste bags for organic waste. The areas of application for these sustainable plastics are agriculture and horticulture, but also textiles, packaging, short-lived consumer goods and the automotive industry.
But: The term bioplastic is basically not protected and is also used for other plastics, such as mixtures of petroleum- and raw material-based plastics.
So while some plastics are biobased, others are biodegradable - and a few combine these two descriptions. But we are dealing with two very different descriptions here:
Biodegradability
For this property, there is DIN EN 13432, which precisely defines that a biodegradable material must be more than 90 percent degraded - into carbon dioxide, water and biomass - within a specified period of time and under clearly defined conditions. The conditions relate to temperature, oxygen and moisture, as well as microorganisms and fungi.
As already described: This biodegradability does not require the plastic to be made from renewable raw materials, but depends solely on the chemical structure of the material and thus on its ability to convert into natural metabolic end products in the course of biological activities.
And this is precisely where the misunderstandings often begin: Bioplastics are often enough equated with a plastic that is both biobased and biodegradable - and this is extremely rare. True biodegradability is in fact only given in very few cases.
The fact is, however, that this process itself in industrial Composting facilities is not happening fast enough. As a result, the bags end up in the finished compost as contaminants, i.e. material that has not rotted, and have to be removed manually. It is unavoidable that up to a third of this valuable soil is lost again in this way. In addition, the Workload enormous.How does bioplastic behave in nature?
The advantages compared to petroleum-based plastics are only slight: In nature, too, the conditions with regard to decomposition are anything but optimal, especially since fungi and decomposing enzymes are lacking. So the bitter conclusion is that even the common bioplastic resists decomposition in nature for a very long time - and in the cold sea for years.
 With (a few) exceptions: Some bioplastics you can actually compost. You can recognize them by a special seal that explicitly confirms their garden compostability. |
Not to be underestimated: Recyclates as sustainable plastics
That doesn't sound very encouraging? From our point of view, these are steps in the right direction that should be consistently pursued. And that brings us to a topic that is just as important: recycling plastics that have already been processed.
Here we see an exciting potential for environmental protection: recyclates are in fact materials that can be reprocessed into granules after their intended use and used again to manufacture plastic products.
The problem is that this requires plastics to be separated by type - and this is not always possible. So far, there are only closed cycles for some plastics such as PET: A large proportion of the processed material flows back as recyclate and is reprocessed. Unfortunately, 100 percent is not possible, so a proportion still has to be thermally recycled and replaced.
Other recyclates consist of mixed plastics that can certainly be reused. However, with each cycle, the material requirements decrease. This happens, for example, with returnable beverage crates or in asphalt production. Up to 15 percent of plastic waste is added to the bitumen mixture to make the road surface not only cheaper but also more temperature-stable.
Sustainable bioplastics - is that even possible?
From our point of view, this is the question of our time. So far, it has been answered by the Federal Environment Agency in such a way that a bioplastic that is actually sustainable must demonstrate a positive life cycle assessment according to DIN EN ISO 14040 as well as 14044 - and this is not (yet) the case. So far, no manufacturer of sustainable plastics has been able to prove, within the framework of such a balance sheet or other types of studies, what the ecological effects of the bioplastics offered look like in reality.
In principle, such a bioplastic would have to demonstrate its ecological superiority over petroleum-based plastics at some points. To do so, it would have to meet the following criteria:
- The raw materials for plastic production come from sustainable agriculture. In the best case, they are residual materials from the production of agricultural products and food.
- The plastic products can be used several times.
- When the product life cycle comes to an end, the plastics can be recycled to a high standard - either as materials or as energy.
Conclusion: Sustainable plastics - there is still a lot to do!
Currently, no bioplastic available on the market meets these requirements. Nevertheless, we already see encouraging development steps in the bioplastics and biodegradable plastics available today. These new materials are already being used in a wide variety of areas of our economy.
We as packaging specialists also benefit from this. Of course, developments must continue in order to relieve our environment in the long term as well. However, from our point of view, it is just as important to recycle plastics that have already been processed and that can be reprocessed into useful products without any problems. It's a big topic - and of course we'll stay on the ball for you.
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Do you have any questions about the sustainability of our packaging solutions? Feel free to contact our expertswho will be happy to support you or write to us via hello@palamo.com. |
