Bioplastics of 21st Century

From the history of bioplastics, it is easy to conclude that the prefix bio- does not ensure an environmentally friendly product. The overall sustainability of the material must be monitored throughout its life cycle.

A sustainable bioplastic should avoid the following problems:


extraction of mineral resources, deforestation, competition with food and feed production. 


use of hazardous chemicals in bioplastic production occupational health risks, environmental contamination at the processing site.


material quality must be sufficient a low lifespan of the product increases its environmental footprint.

End of life

recycling of bioplastics must be made available. In the case of biodegradable bioplastics, conditions for ideal degradation must be provided – waste management must be addressed even in the case of biodegradable materials.

Current research and development focus on materials that can prevent all of the issues mentioned above. These are mainly biodegradable materials from renewable sources. The most common are starch-based materials, followed by polylactic acid (PLA) and polyhydroxyalkanoates (PHA). However, the range of raw materials is wide – sugars, proteins, cellulose, lignocellulose, chitin, chitosan, plant residues, fungi, algae. But not all sustainability criteria are always met.

Polyactic Acid (PLA)

PLA was discovered in the 1920s but has not been commercially produced due to its high cost. This changed in 1989 when Patrick R. Gruber discovered how to produce PLA from corn. This enabled Novamont to develop bioplastics under the commercial brand MATER-BI. In 1997, Cargill and Dow Chemicals also started producing PLA from corn. In 2001 they started commercial production and since 2005 we know this company as NatureWorks, one of the main producers of PLA. PLA is durable bio-based polymer, but it still holds some drawbacks, mainly: 1) competition with food and feed production, 2) insufficient biodegradability and improper waste management.

Polyhydroxyalkanoates (PHA)

In 1926, French agronomist Maurice Lemoign discovered polyhydroxybutyrate (PHB) in the bacterium Bacillus megaterium – a storage polymer for microorganisms. It was not until the 1960s that science also focused on other PHAs produced by bacteria, P3HV and P3HHx. It took a long time for Lemoigne’s discovery to be put into practice – in 1983, Malborough Biopolymers was founded and introduced a material called Biopol. In 1992, a study describing the production of PHB in plants was published in Science. This attracted the attention of Monsanto, which bought Biopol in 1996 and began producing it using plants instead of bacteria. In 2001, Metabolix Inc., now known as Yield10 Bioscience, took over the production and dedicated itself to the production of PHAs using oilseed plants. It should be noted that the development of technologies to produce PHA (whether in microorganisms or plants) was enabled by advances in molecular biology and genome modification. By 2006, about 150 different PHAs were known. Commercial production has reduced the cost of these materials and they began to be tested extensively for various applications with great potential in medicine. Current research focuses mainly on the production of PHAs from waste sources and their recycling.

BioPropylene (Bio-PP) and Bio-Ethylene (Bio-PE)

Polyethylene is the most abundantly used plastic in the world. Ethylene, monomer of PE, is generally produced from petroleum. However, new approaches allow to produce ethylene from bio-ethanol. This Bio-PE based in crop fermentation has the same chemical and material properties as oil-based PE, also with regards to the mechanical recycling process. This is a big advantage as the waste management of Bio-PE and Bio-PP is already established and these materials can be fully recycled. However, they are not biodegradable as much as oil-based plastics, so they contribute to plastic waste pollution. Production of Bio-PP requires bio-isobutanol. With respect to the production of Bio-PE, the process followed to obtain bio-PP has been less explored. Thus, Bio-PP is just entering the market.

The following table summarizes the most important plastics used. It evaluates the polymers based on their origin (bio-based, biosynthesized) and their end-of-life (compostable, home compostable). Biosynthesized materials are those that gained their chemical structure in living organism like cellulose or starch from plants or PHA from bacteria. Other bio-based polymers originate in renewable sources, but their chemical structure is man-made. These are bio-PE or PLA. Biodegradability is very complex term which must be further specified. Here you can compare biodegradability in two conditions most important for bioplastics waste management – composting and home composting. Industrial composting allows temperature and humidity regulation with higher temperature for decomposition. Home composting cannot be regulated and the temperature and other conditions for biodegradation vary.

* Industrially compostable: “Industrially compostable packaging” refers to the ability of packaging to biodegrade and decompose only in a commercial composting facility. Industrial composting facilities treat the packaging at high temperatures (above 55 °C, much higher than can be achieved in home composting) to accelerate degradation of the material. In accordance to the norm EN 13432. Home compostable: Packaging labeled as “home compostable” means that the customer can simply place the packaging in the home compost bin. No EU-wide norm available yet! Fully bio-based PET has been long presented by manufacturers, but never commercialized. PGLA – lactic acid is bio-based but glycolic acid is usually synthesized artificially. CA and silicone rubbers can slowly degrade, the biodegradability of PET and PU has been established under specific laboratory conditions.


1 Koller, M. and A. Mukherjee. Polyhydroxyalkanoates – Linking Properties, Applications and End-of-life Options. Chem. Biochem. Eng. Q. 2020, 34(3): 115-129. doi: