Ask the Expert: Natural Polymers - Nature's "Plastics"
The summer holiday is slowly coming to an end, and we all know what that means: it’s time to get back to the office. Instead of immediately emptying out your mailbox, contacting your business partners, or jumping into the next meeting - how about a slightly calmer start?
So, instead of getting back to the office, let’s get back to school! The classes that are on today’s schedule are history, chemistry, a bit of legal studies, and environmental sciences. Now you might wonder what these classes have in common with traceless?
Over the last years, plastic – and to be more precise, plastic pollution – has been a hot topic. From NGOs, to governments, to campaigns like Zero Waste, to alternative materials like ours, it seems everyone is trying to do something against plastic pollution. And not without a reason, as plastic pollution is considered one of the biggest threats to our planet nowadays. Exactly with this reason in mind, our co-founder Anne developed a holistically sustainable alternative material to conventional plastics and bioplastics: traceless. And the secret behind our materials is that they are based on natural polymers. In this blogpost, we will shed some light on these substances from various angles: We will find out where we can find them in nature (biology), travel back in time to the roots of plastics (history), go on a little excourse to the legal side (law), and of course learn about environmental impact. But first, we start with a little chemistry class, to learn what exactly these subtances are…
First period: Chemistry
To begin with, lets discuss the term ‘’polymers’’ - because what exactly are they? The term "polymer" derives from the Greek word "polys" (meaning "many, much") and "meros", (meaning "part"). Polymers are macromolecules, consisting of many identical small units that are strung together like a chain. While both plastics and traceless consist of polymers, giving them their flexibility and stability, we know already that there is some significant differences between them. Plastics contain synthetic polymers, and traceless materials on the other hand are based on natural polymers.
To learn a bit more about these special substances the biochemical secrets behind them, let’s ask our expert, (or should we call him teacher?) Arjun Rajesh. As traceless’ product developer, he is our specialist when it comes to nature’s polymers, because they are the subject of his daily work in the lab of our R&D department.
Synthetic polymers and natural polymers… Arjun, can you help us understand the difference?
Arjun: The main criteria is the origin, so the question: What is the resource, and where were these molecules created? Synthetic polymers are man-made and synthetically created in a chemical process called polymerization, mainly using fossil-based chemicals as a raw material. They are the main component in conventional plastics. Some plastic materials you might know are polyethylene (PE), or polypropylene (PP). The German word is “Kunst-stoff”, meaning “synthetic substance”. This already indicates that they are an artificial substance. Natural polymers on the other hand are also long chain molecules, but they occure in nature, and are created by living organisman, so plants or animals/humans.
Another term we hear often recently is the term of “biopolymers”. Is that the same as natural polymers?
Well, not exactly! In short: All natural polymers are biopolymers, but not all biopolymers are natural polymers. “Biopolymers” is a general term for all polymers that are derived from biomass. The definition also includes polymers that are not created in nature, but in an artificial process - for example PLA, which is biosynthesized by microorganisms, using plant resources. In most definitions, even bio-based “drop-in”-plastics are included under the term biopolymers. So, bioplastics that are derived from biomass, but are chemically identical to conventional plastics. Natural polymers, sometimes described as “natural biopolymers”, are a special kind of biopolymers: Those that are not only made from biomass, but directly created in plants or animals, and naturally occuring. When it comes to using these substances in technical applications, and the sustainability of these materials, there is of course a difference between, say, bio-based plastics and natural polymer materials. Therefore, we at traceless try to be as precise as possible in our communication, and prefer to talk about “natural polymers”. Thank you, Arjun!
Second period: Biology
Now that we’ve learned that a wide range of natural polymers occurs in nature, too, it’s time to venture out with our magnifying glasses and look around: Where exactly can we find these “plastics of nature”?
We really don’t have to search long: The most abundant organic compound on earth is a natural polymer! It is cellulose, forming the cell walls of plants - the most common organic compound on earth. We use it to produce paper and cotton. Other examples of natural plant polymers are lignin, proteins or starch, but also natural rubber contains natural polymers. Natural polymers with animal (or human) origin are chitin, or the substances forming silk or wool.
traceless materials are a new generation of plastic-like materials that are based on these natural polymers - but the actual idea is rather quite old… How old exactly, you will find out during history class!
Third period: History
The idea of using natural polymers is way older than the idea of using synthetic plastic materials. For thousands of years, people have made use of the beneficial properties of natural polymer materials. So, today we’ll make a jump back in time and discover the history of plastics, natural and synthetic polymers…
Already a millennium and a half before Christ, the Olmecs in Mexico played with balls made of a natural polymer material: rubber! Another example are the medieval craftsmen who made lantern windows out of translucent slices of animal horn, which is based on the natural polymer keratin.
It was in 1862 that Alexander Parkes introduced the world’s first-ever man-made “plastic” – Parkesine, based Nitrocellulose, a chemically modified version of the natural polymer cellulose. The material didn’t start to truly show its potential until John Wesley Hyatt discovered a way to manufacture an improved version of it: Celluloid. Shortly after, Swiss chemist Jacques E. Brandenberger developed Cellophane, a transparent packaging film based on regenerated cellulose.
The year 1907 marked another turning point: With the Duroplast Bakelite (by Leo Baekeland), the first fully synthetic plastic was invented - industrially produced and derived from fossil fuels. In the 1950ies, the chemical industry finally started manufacturing various synthetic plastic materials in big amounts - it was the beginning of the “plastic age”. While their invention brought great progress to modern life, their excessive use has brought a downside, namely the one of plastic pollution.
Now, let’s make a leap in time to the present: Our co-founder Anne wanted to find a solution to plastic pollution, and decided to go back to the roots of plastic, this is how she developed a new technology for natural polymer materials. The result: traceless materials, with which we hope to make history!
If we've just made you cusrious to learn more about the history of plastics, we highly recommend to visit the current exhibition in the famous Vitra Design Museum, called "Plastics. Re-Making our World".
Forth period: Law
We’ve already learned that there’s a clear chemical distinction between plastics - so, materials made from synthetic polymers - and natural polymer materials. This clear difference also plays a role for the legislator - especially with regard to the new regulations on plastic. Which materials are legally considered plastics, and which are not? Let's have a look at the latest and most relevant directive on that topic: The Directive (EU) 2019/904, better known as The Single-Use Plastics Directive. Here, it says:
"Plastics are usually defined as polymeric materials to which additives may have been added. However, that definition would cover certain natural polymers. Unmodified natural polymers, within the meaning of the definition of ‘not chemically modified substances’ in point 40 of Article 3 of Regulation (EC) No 1907/2006 of the European Parliament and of the Council ( 13 ), should not be covered by this Directive as they occur naturally in the environment.’’ (EU) 2019/904, article 11, derived from https://eur-lex.europa.eu/eli/dir/2019/904/oj
With this definition, the set points out the difficulty of a general polymer term, and makes it clear that materials made of unmodified natural polymers must be excluded from the plastic definition - otherwise a material such as paper, which consists of natural polymers, would also fall under it. We’ve learned: Natural polymer materials are legally not plastics, and therefore not affected by regulations targeting plastic use. This opens up great application potential for natural polymer materials, especially when it comes to products that are no longer allowed to be produced from plastics.
Fifth period: Environmental Sciences
Especially within the plastic industry, many might wonder: Why use natural polymers, when
chemists and engineers have worked for so many decades to optimise synthetic plastics? Well, we at traceless like to look at this question from the opposite angle: Why go to the trouble of producing synthetic polymers at all, when you can also use those that nature has already produced?
Even though the methods of producing polymers synthetically have been optimised for decades, they are still very energy-intensive, not to mention the fossil resources that are usually used. Our process to extract natural polymers is way more efficient, consuming only around a quarter of plastic production energy - all while using non-fossil, fully renewable raw materials.
But the greatest advantage of materials made from natural polymers is revealed at the end of their life. Unlike their synthetic relatives, they are much easier degradable in nature. This is because the biodegradation out there is done by natural microorganisms - and they are much better adapted to the substances they have known for thousands of years already.
We hope that after this day back in school, we have convinced you of our mission to turn the old idea of using natural polymers into a technology that will secure us a future on a healthy planet!