It is not easy to answer the question: What are Bioplastics? There are two attributes related to bioplastics: bio-based and biodegradable plastics. Not everyone agrees on this.
Definitions evolve over time and sometimes a definition is politically and economically loaded because of the consequences one definition will have above the other.
Etymology reminds us that sometimes we use words in a wrong sense or that popular interpretations or conventional usages of words may not be …etymologically correct.
Bio-based, Bio-sourced and Plant-based
The Oxford Dictionary defines “bioplastics” as a type of biodegradable plastic derived from biological substances rather than petroleum. This is what we call “bio-based”. The “bio” refers to biological.
However, oil and petrol are to some extend also “biological”. They’re the residue of biological entities such as animals and plants that have been pressured and processed for millions of years.
Maybe the “Bio” from bio-based and bio-sourced should not only refer to “biological (entities)” but also to “biologically friendly” in the sense that they respect the fauna and flora and the ecosystem. Then again, how do you define biologically friendly?
Another aspect would be to look at the renewability. To what extend can you renew or how long do you need to renew a plant or a crop? To what extend or how long do you need to renew oil and petrol?
Biobased plastic or Bioplastics are plastics made from renewable biomass such as:
- vegetable fats and oils,
- corn starch
- pea starch
- potato starch
- sugars from sugar cane and sugar beats
However, recently there have been many inventions and scientific breakthroughs. We will be able to make bioplastics from
When the renewable biomass comes from a plant, it can also be referred to as plant-based plastics.
Plastics vs Polymers
When we use the word plastics, we mean polymers. Plastics is not a substance or material, it’s an attribute (plasticity).
Plasticity is the name used to describe the property, feature or attribute of all materials which can deform irreversibly without breaking. This attribute refers to the production process and not the usage. We can mould a polymer to give it a specific form (ex: a plate). The polymer survived the moulding and production process because of its plasticity.
What we refer to as plastics are usually organic polymers of high molecular mass mixed with other substances (additives). These polymers and additives are usually derived from petrochemicals except in the case of bioplastics…or shall we say biopolymers.
Biodegradation and Compostability
Bioplastics is also capable to biodegrade or decompose back into its natural elements, under the action of bacteria or enzymes (bio-degradable).
Applications of Bioplastics
Applications of bioplastics cover a wide area ranging from
- rigid and flexible packaging materials;
- food and drinks containers;
- dining utensils;
- electronic devices;
- automotive and airplane parts;
- cable sheaths and casings;
- noise and thermal insulation panels.
End of life, Lifecycle and Waste Management
When a plastic or bioplastic object has accomplished its purpose it reaches it’s end of life and is usually discarded. Now comes the billion dollar question: what shall we do with the plastic and bioplastic waste? Here are some options:
Firstly, bioplastics needs to be sorted, collected, treated and processed for its second life. How do you differentiate between different types of bioplastics? Some packaging are made from several materials often referred to as laminates. How do we separate these layers? How do we sort them? How do we remove the glue, colorants and additives? This falls under waste management.
In the following graph, we see the decision to include fossil-based plastics that are biodegradable under the term bioplastics. This is not a universal definition, this is a political or subjective definition. This may change over time or may not be agreed upon by everyone.
- 1862 – Alexander Parkes creates the first man-made polymer from an organic material derived from cellulose. It was a bio-based plastic and was called Parkesine.
- 1926 – French scientist Maurice Lemoigne developed polyhydroxybutyrate (PHB) from bacterium Bacillus megaterium. The first bioplastics made from bacteria.
- 1907 – Leo Baekeland invents Bakelite and it will be described as a National Historic Chemical Landmark due to its importance. Bakelite was a synthetic plastic that was revolutionary for its electrical nonconductivity and heat-resistant properties in electrical insulators, radio and telephone casings and such diverse products as kitchenware, jewelry, pipe stems, children’s toys, and firearms.
- 1990 – Imperial Chemical Industries (UK) developed a bioplastic that was biodegradable. It was called named Biopol.
- 1990 – Commercial demand for bioplastics starts to develop, driven by oil price volatility and environmental concerns.
The environmental impact of Bioplastics should be measured on following points:
- Climate change, carbon footprint and greenhouse gasses
- use of farmland for Bioplastics instead of food production
- Reduced dependence on petroleum
- End-of-life options
- life cycle analysis
Types of Bioplastics
- BDO 1.4 butanediol
- Bio-based PET
- PEF Polyethylene Furanoate
- PLA polylactic acid
- PHA Polyhydroxyalkanoate
- PBT polybutylene terephtalate
- PBS polybutylene succinate
- PDO 1.3 propanediol
- PU Bio-based Polyurethane
- PTT polytrimethylene terephthalate
- PA10 PA11 : bio-polyamides from oil plants (Castor)