Biodegradable Plastics Definition, Types, Impact, and Companies

Biodegradable plastics are plastics which can undergo biodegradation or biological decomposition, to yield simpler byproducts. This article discusses biodegradable plastics definition, types, impact and companies, as follows;

 

-Biodegradable Plastics Definition: 6 Ways to Define Biodegradable Plastics

-Biodegradable Plastics, The Ecosystem, and Environment

-Biodegradable Plastics and Bioplastics: A Comparison

-How Biodegradable Plastics are Produced

-Types of Biodegradable Plastics

-Products Made from Biodegradable Plastics

-Companies Involved in the Manufacture of Biodegradable Plastics

-Conclusion

 

 

 

 

Biodegradable Plastics Meaning: 6 Ways to Define Biodegradable plastics

Biodegradable plastics are plastics that can be broken down by biological processes and organisms to yield water and carbon dioxide.

Because biodegradable plastics can be transformed as a result of biological factors, these factors can be used to describe them, as follows;

Biodegradable plastics are plastics which are produced from various types of biomass and biopolymers, such as straw, vegetable fats and oils, sawdust and corn starch [6], and can be degraded by microorganisms like bacteria and fungi.

Within the same biological context, an alternative biodegradable plastics meaning, as a product of raw-material processing, is as follows;

Biodegradable plastics are plastics derived from the processing of biopolymers like proteins, starch, chitosan, pectin and cellulose, which are produced by plants and animals [16].

Based on the above definition, it is obvious that biodegradable plastics (or bioplastics) differ from non-biodegradable plastics in their composition, since the non-biodegradable plastics are usually derived from petroleum hydrocarbons.

Although biodegradable plastics are capable of undergoing biological and biochemical decomposition, there are generally a set of conditions which are optimal for their decomposition. This is portrayed in the definition below;

Biodegradable plastics are plastics that may be made from biological materials, and which tend to decompose under a specific set of conditions with regards to timeframe and medium (compost, water, soil) of decomposition.

Unlike petroleum-based plastics which may take decades or centuries to breakdown completely, the average time required for biodegradable plastics to decompose, lies between 12 to 24 weeks, although some bioplastics may take a few years to decompose. These rates are possible provided the optimal conditions for degradation are in place.

What the above definition implies is that biodegradable plastics are of different types, and have different degradation mechanisms and dynamics.

The existence of different types of biodegradable plastics is expressed in the following definition;

Biodegradable plastics are plastics which can undergo biodegradation through various biochemical processes that include oxidation, hydrolysis and photo-degradation, and which will breakdown effectively under specific conditions to yield water, carbon dioxide and compost.

One of the most important issues with regards to biodegradable plastics is their effect on the environment. The importance of this factor is influenced heavily by the concept of sustainable development and the efforts to achieve sustainability.

Therefore, environmental impact can form the theme by which biodegradable plastics are defined, as follows;

Biodegradable plastics are plastics which are ideal for mitigating environmental degradation, due to their ability to undergo natural biodegradation, and return to the ecosystem in the form of nutrients that can be recycled within the energy pyramid.

 

Biodegradable Plastics, The Ecosystem, and Environment

Generally, biodegradable plastics are eco-friendly because they can breakdown completely without posing any significant threat to the environment.

Because of the problem of pollution which is posed by non-biodegradable plastics, there have been efforts to improve the effectiveness of decomposition of bioplastics.

This measure will help to ensure that the use of biodegradable plastics is fully safe and sustainable.

While they can be described as a suitable alternative to non-biodegradable plastics, biodegradable plastics may not always be good for the environment.

For example, oxo-degradable plastics can be harmful to marine ecosystems even after their disintegration, as they may breakdown to form microplastics which are hazardous when ingested by aquatic organisms [15].

The reason why biodegradable plastics are not always good for the environment, lies in the fact that the rate of biodegradation depends on variable physicochemical and ecological factors, such as temperature, microbes, pH, and humidity [12].

Because of these potential challenges, a variety of methods have been designed to treat biodegradable plastics effectively.

One of such methods is thermal decomposition by pyrolysis. When biodegradable plastics undergo pyrolysis, they are converted to simple byproducts like carbon dioxide, methane and char.

Biodegradable plastics can be recycled. However, they are usually separated from non-biodegradable plastics and are hardly ever recycled. This is because the conditions of usage and disposal can significantly reduce the quality of biodegradable plastics, compared to non-biodegradable ones.

waste management, plastic waste, biodegradable plastics
Biodegradable Plastics are Not Usually Recycled (Credit: Streetwise Cycle 2010)

 

It can also be said that biodegradable plastics are renewable, because they can be recycled effectively in nature.

 

Biodegradable Plastics and Bioplastics: A Comparison

Unlike bioplastics, not all biodegradable plastics are composed of bio-based materials. This is the basic difference between the two types of plastics.

Biodegradable plastics cover a wide range of types. It covers all types of plastics that can undergo biodegradation [18].

This include plastics that are composed of synthetic and organic materials, as well as compostable plastics (that can decompose when composted), among others.

For example, oxo-biodegradable plastics are usually made from petroleum derivatives. They are still biodegradable plastics because they can undergo biodegradation and breakdown to form simpler compounds like carbon dioxide and methane.

On the other hand, bioplastics are all made from bio-based materials, like cellulose and starch. These plastics are a subcategory of the biodegradable plastics, which are identified based on their biomass composition.

 

How Biodegradable Plastics are Produced

Biodegradable plastics can be made from renewable biomass materials such as cellulose and starch.

The raw materials used to manufacture these plant-based biodegradable plastics include corn, sugarcane and micro-organic material such as fungi mycelium.

In order to convert these raw materials into biodegradable plastics, they are usually subjected to polymerization or poly-condensation reactions. These reactions are usually driven by physicochemical factors like temperature and catalysts.

An example of a biodegradable plastic that is produced by polymerization is Polylactic Acid (PLA).

Polylactic acid is made from lactide and lactic acid monomer [7], which is a derivative of biomass fermentation, and an intermediate product of anaerobic digestion of sugars like cellulose.

During the polymerization of lactide and lactic acid monomers to form PLA biodegradable plastics, zeolites are used as catalyst [2].

When manufacturing biodegradable plastics, some stabilizing chemicals may be applied to prevent the plastics from degrading too readily.

However, the presence of biomass-based materials in its composition makes the biodegradable plastic more prone to microbial decomposition than traditional plastics.

The use of biomass to manufacture biodegradable plastics can be viewed as a form of carbon capture and sequestration, because it temporarily prevents the release of carbon dioxide (a greenhouse gas) into the atmosphere through biomass decomposition.  

This is a huge contrast to non-biodegradable plastics, which are produced from petroleum derivatives and whose manufacture typically involves greenhouse gas emissions [17].

 

Types of Biodegradable Plastics

The six main types of biodegradable plastics are hydro-biodegradable, oxo-biodegradable, cellulose-based, protein-based, starch-based, and synthetic.

These types are classified based on mode of biodegradation, and composition. Each category is discussed briefly below;

 

Types of Biodegradable Plastics Based on Mode of Biodegradation

1). Hydro- Biodegradable Plastics

Hydro-biodegradable plastics are the category of biodegradable plastics whose primary mechanism of biodegradation is hydrolysis [8].

During hydrolysis, water reacts with the biodegradable plastics to produce simpler compounds like carbon dioxide.

Raw materials used to manufacture hydro-biodegradable plastics include petroleum derivatives, wheat, corn and sugarcane.

An advantage of this type of biodegradable plastics is their rate of decomposition. Hydro-biodegradable plastic is the most biodegradable type of plastic. This is because it decomposes at a much faster rate than other types of biodegradable plastics.

The main disadvantage of hydro-biodegradable plastics is the release of greenhouse gases during their manufacture and decomposition. Methane is produced in significant amounts when hydro-biodegradable plastics undergo decomposition.

Aside greenhouse emissions, hydro-biodegradable plastics are relatively expensive and energy-intensive to manufacture, and are not very durable compared to other types of biodegradable plastics.

2). Oxo-Biodegradable Plastics

Oxo-biodegradable or oxo-degradable plastics are plastics which undergo decomposition through a biochemical mechanism involving oxidation.

They are usually composed of the same petroleum-based materials used to manufacture conventional plastics [1]. However, additives known as pro-degradants are included in the compositional makeup of these plastics, to make them biodegradable.

In several cases, the additives are bio-based and may consist of materials like cellulose and starch.

Due to the presence of these additives, the oxo-biodegradable plastic is susceptible to microbial decomposition at the end of its lifespan, which is determined by the composition of the plastic and the type of additive.

Although this type of biodegradable plastic has a slower rate of biodegradation than hydro-biodegradable plastics, it is more sustainable than traditional plastics and is generally considered to be safe for the environment.

 

Types of Biodegradable Plastics Based on Composition

3). Cellulose-Based Biodegradable Plastics

Cellulose-based biodegradable plastics are manufactured from cellulose or its derivatives.

The most common raw material used in the production of cellulose-based biodegradable plastics is cellulose acetate, which is produced by plant biomass such as wood pulp and cotton linters [10].

Because of their biological composition, cellulose-based plastics can breakdown completely and effectively to produce carbon dioxide and water, among other inorganic materials.

cellulose for manufacturing biodegradable plastics
Cellulose is a Raw Material for Manufacturing Cellulose-Based Biodegradable Plastics (Credit: Okram 2011 .CC BY-SA 3.0.)

 

4). Protein-Based Biodegradable Plastics

Protein-based biodegradable plastics have been used in food packaging among other applications.

Soy protein is a common raw material used to manufacture protein-based biodegradable plastics, based on a variety of methods [4].

These methods are generally complex and involve challenges, because there is limited industrial experience in the use of soy protein in manufacturing [11].

The use of proteins to manufacture these plastics implies that they are renewable. However, protein-based biodegradable plastics are usually stiff and may require additives to increase their plasticity and flexibility.

5). Starch-Based Biodegradable Plastics

Starch-based plastics are usually composed of a combination of starch and compostable polymers like polylactic acid (PLA), and polybutylene succinate (PBS) [9].

The biggest advantage of this type of biodegradable plastic is its rate of decomposition. The presence of starch makes starch-based plastics to decompose readily compared to other types.

Because of this capability, starch-based plastics are believed to be a good, renewable option for reducing the carbon footprint of the plastic manufacturing industry.

However, these plastics have some drawbacks, such as high permeability to vapor, and unfavorable water-sensitivity, both of which have negative effects on the durability of the plastic [13].

6), Synthetic Biodegradable Plastics

Synthetic biodegradable plastics are composed of degradable polymers which are produced from synthetic processes.

Examples of such polymers include polylactic acid (PLA) and polyglycolic acid (PGA) [3]. Polyethylene succinate (PES) is yet another example of a synthetic biodegradable polymer.

Generally, renewable raw materials are used to produce synthetic biodegradable plastics. However, the processes by which these polymers are transformed to plastic, involve non-biological reactions.

 

Products Made from Biodegradable Plastics

1). Bottles

Biodegradable plastic bottles are becoming a widely-adopted commodity in the manufacturing industry.

They are used in packaging various domestic and industrial products, and are continuously being modified to improve their durability.

Polymers like polyhydroxyalkaniates (PHAs) and polylactic acid (PLA) are commonly used to manufacture biodegradable plastic bottles.

biodegradable plastics, bioplastic bottles
Biodegradable Plastics in the Bottling Industry (Credit: F. Kesselring, FKuR Willich 2009 .CC BY-SA 3.0 DE.)

2). Bags

The scale of the disposable-bag manufacturing industry implies that efforts must be made to address environmental impacts of these products after their disposal.

This is the reason why biodegradable plastics have been integrated into the process of manufacturing disposable bags.

Biodegradable plastic bags are viewed as an eco-friendly solution to pollution and environmental degradation challenges that arise with the disposal of polyethene. They may be made from any of various biodegradable polymers, and generally reduce the environmental footprint of the packaging industry.

Although the expected degradation period for these products falls within months, some assessments suggest that they may take over three years to breakdown completely [14]. This means that further improvement is required to make biodegradable plastics an optimal option for producing disposable bags.

biodegradable plastics, bioplastic bag
Biodegradable Plastics in the Manufacture of Disposable Bags (Credit: Safwan Rahman 2018 .CC BY-SA 4.0.)

 

3). Food Packaging

In food packaging, biodegradable plastics have found application as a material for the manufacture of products like disposable plates, cups, straws and cutlery.

The biodegradable polymers used to make these products are relatively durable and tolerant, so as to withstand extreme temperature and mechanical stress.

Food packaging with biodegradable plastics is considered to be an essential step toward establishing a circular economy.

Many of these materials are bio-based, and derived from biomass, in the form of cellulose, polylactic acid, starch and gelatin, among others [5].

 

Companies Involved in the Manufacture of Biodegradable Plastics

The table below provides brief information on some biodegradable plastic manufacturing companies in the world (in alphabetical order);

Company Headquarters Address Year of Founding Products
Algiknit New York, USA 2017 Seaweed-based yarn, bioplastics
AirCarbon Singapore 2019 Hydro-biodegradable plastics
An Phat Holdings Hanoi, Vietnam 2017 Biodegradable plastics
Aquapak Polymers Birmingham, UK 2011 Biodegradable plastics
Avantium Amsterdam, Netherlands 2000 Bio-based textiles, bioplastics
BASF Ludwigshafen, Germany 1865 Chemicals, plastics, fertilizer
BE Green Packaging South Carolina, USA 2007 Compostable packaging
BioApply Polymers Gland, Switzerland 2011 Compostable, reusable packaging
Biome Bioplastics Southampton, UK 2002 Bioplastics, flexible films
Biosphere Plastic Oregon, USA 2012 Bioplastics
Braskem São Paulo, Brazil 2002 Chemicals, Thermoplastic resins
Cardia Bioplastics Melbourne, Australia 2002 Compostable resins
Eastman Tennessee, USA 1920 Chemicals, resins
Ecoware Delhi, India 2010 Biodegradable food packaging
Futamura Aichi, Japan 1947 Bio-based resins
Genecis Bioindustries Ontario, Canada 2016 PHA biodegradable plastics
Genomatica California, USA 1998 Chemicals, bio-based plastics
Green Dot Bioplastics Kansas, USA 2011 Compostable Bioplastics
Greenlid Envirosciences Ontario, Canada 2013 Compostable Bioplastics
Instrumental Polymer Technologies California, USA 2009 Chemicals, resins
Mango Materials California, USA 2010 Biopolymers, bio-based textile
Metabolix Massachusetts, USA 1992 Biodegradable plastics
Microrio LLC Texas, USA 2018 PHA Biodegradable plastics
Mitsubishi Chemical Tokyo, Japan 2005 Chemicals, polymers
NatureWorks Minnesota, USA 1989 PLA bioplastics
Neste Espo, Finland 2005 Chemicals, plastics
Novamont Novara, Italy 1989 Compostable bioplastics
Polymateria London, UK 2015 Biodegradable plastics
Radical Plastics Massachusetts, USA 2018 Biodegradable plastics
RWDC Singapore 2015 Biodegradable plastics (mainly for food packaging)
Scindo London, UK 2020 Bioplastics, recycling services
Sulapac Helsinki, Finland 2016 Biodegradable plastics
The Roquette Group Lestrem, France 1933 Starch-based polymers, pharmaceuticals, nutritional supplements
TIPA HaMerkaz, Israel 2010 Bio-based compostable packaging
Wells Plastics Starffordshire, UK 1984 Chemicals, oxo-biodegradable plastics
Verdastro Shah Alam Selangor, Malaysia 2020 Bioplastics
Xampla Ltd. Cambridgeshire, UK 2018 Protein-based bioplastics

 

 

Conclusion

Biodegradable plastics are plastics which can undergo decomposition or biodegradation to form simpler compounds like carbon dioxide, methane and water.

The types of biodegradable plastics are;

  1. Hydro- Biodegradable Plastics
  2. Oxo-Biodegradable Plastics
  3. Cellulose-Based Biodegradable Plastics
  4. Protein-Based Biodegradable Plastics
  5. Starch-Based Biodegradable Plastics
  6. Synthetic Biodegradable Plastics

These types are classified based on their mode of degradation, and their composition.

 

Products made from biodegradable plastics include

  1. Bottles
  2. Bags
  3. Food Packaging

 

References

1). Abdelmoez, W.; Dahab, I.; Ragab, E. M.; Abdelsalam, O. A.; Mustafa, A. (2021). “Bio-and oxo-degradable plastics: Insights on facts and challenges.” Polymers for Advanced Technologies 32(4):1-16. Available at: https://doi.org/10.1002/pat.5253. (Accessed 5 May 2022).

2). Balla, E.; Daniilidis, V.; Karlioti, G.; Kalamas, T.; Stefanidou, M.; Bikiaris, N.; Vlachopoulos, A.; Koumentakou, I.; Bikiaris, D. N. (2021). “Poly(lactic Acid): A Versatile Biobased Polymer for the Future with Multifunctional Properties—From Monomer Synthesis, Polymerization Techniques and Molecular Weight Increase to PLA Applications.” Polymers 13(11):1822. Available at: https://doi.org/10.3390/polym13111822. (Accessed 4 May 2022).

3). Bose, R. J. C.; Kim, M.; Chang, J. H.; Paulmurugan, R.; Moon, J. J.; Koh, W.; Lee, S.; Park, H. (2019). “Biodegradable polymers for modern vaccine development.” J Ind Eng Chem. Available at: https://doi.org/10.1016/j.jiec.2019.04.044. (Accessed 4 May 2022).

4). Chalermthai, B.; Chan; Bastidas-Oyanedel, J.; Taher, H.; Olsen; Schmidt, J. E. (2019). “Preparation and Characterization of Whey Protein-Based Polymers Produced from Residual Dairy Streams.” Polymers 11(4):722. Available at: https://doi.org/10.3390/polym11040722. (Accessed 4 May 2022).

5). Chisenga, S. M.; Tolesa, G. N.; Workneh, T. S. (2020). “Review Article Biodegradable Food Packaging Materials and Prospects of the Fourth Industrial Revolution for Tomato Fruit and Product Handling.” International Journal of Food Science 2020(1):17. Available at: https://doi.org/10.1155/2020/8879101. (Accessed 4 May 2022).

6). Dilshad, E.; Waheed, H.; Ali, U.; Amin, A.; Ahmed, I. (2021). “General Structure and Classification of Bioplastics and Biodegradable Plastics.” Bioplastics for Sustainable Development (pp.61-82)Edition: 1st Chapter: Springer, Singapore. Available at: https://doi.org/10.1007/978-981-16-1823-9_2. (Accessed 5 May 2022).

7). Dubey, S. P.; Abhyankar, H.; Marchante, V.; Brighton, J. L.; Blackburn, K. (2016). “Chronological Review of the Catalytic Progress of Polylactic Acid Formation through Ring Opening Polymerization.” International Research Journal of Pure and Applied Chemistry 12(3):1-20. Available at: https://doi.org/10.9734/IRJPAC/2016/27469. (Accessed 4 May 2022).

8). Folino, A.; Karageorgiou, A.; Calabrò, P. S.; Komilis, D. P. (2020). “Biodegradation of Wasted Bioplastics in Natural and Industrial Environments: A Review.” Sustainability 12(15):6030. Available at: https://doi.org/10.3390/su12156030. (Accessed 4 May 2022).

9). Gadhave, R.; Das, A.; Mahanwar, P.; Gadekar, P. (2018) “Starch Based Bio-Plastics: The Future of Sustainable Packaging.” Open Journal of Polymer Chemistry, 8, 21-33. Available at: https://doi.org/10.4236/ojpchem.2018.82003​. (Accessed 4 May 2022).

10). Gilbert, M. (2017). “Cellulose Plastics.” Brydson’s Plastics Materials (pp.617-630). Available at: https://doi.org/10.1016/B978-0-323-35824-8.00022-0. (Accessed 5 May 2022).

11). Grewell, D.; Schrader, J. A.; Srinivasan, G. (2014). “Developing Protein-Based Plastics.” ACS Symposium Series 1178:357-370. Available at: https://doi.org/10.1021/bk-2014-1178.ch015. (Accessed 4 May 2022).

12). Joutey, N. T.; Bahafid, W.; Sayel, H.; El Ghachtouli, N. (2013). “Biodegradation: Involved Microorganisms and Genetically Engineered Microorganisms.” In R. Chamy, & F. Rosenkranz (Eds.), Biodegradation – Life of Science. IntechOpen. https://doi.org/10.5772/56194. (Accessed 5 May 2022).

13). Kadarkarainadar, M. M.; Schlenk, M.; Jawaid, M.; Asim, M. (2019). “Corn and Rice Starch-Based Bio-Plastics as Alternative Packaging Materials.” FIBER 7(4):32. Available at: https://doi.org/10.3390/fib7040032. (Accessed 4 May 2022).

14). Laville, S. (2019). “Biodegradable’ plastic bags survive three years in soil and sea.” Available at: https://www.theguardian.com/environment/2019/apr/29/biodegradable-plastic-bags-survive-three-years-in-soil-and-sea. (Accessed 4 May 2022).

15). Mclauchlin, A.; Thomas, N. L.; Patrick, S. G.; Clarke, J. (2012). “Oxo-degradable plastics: Degradation, environmental impact and recycling.” Waste and Resource Management 165(3):133-140. Available at: https://doi.org/10.1680/warm.11.00014. (Accessed 5 May 2022).

16). Mutmainna, I.; Tahir, D.; Gareso, P. L.; Ilyas, S. (2019). “Synthesis composite starch-chitosan as biodegradable plastic for food packaging.” Journal of Physics Conference Series 1317:012053. Available at: https://doi.org/10.1088/1742-6596/1317/1/012053. (Accessed 5 May 2022).

17). Posen, I. D.; Jaramillo, P.; Landis, A. E.; Griffin, W. M. (2017). “Greenhouse gas mitigation for U.S. plastics production: Energy first, feedstocks later.” Environmental Research Letters 12(3). Available at: https://doi.org/10.1088/1748-9326/aa60a7. (Accessed 5 May 2022).

18). Song, J. H.; Murphy, R. J.; Narayan, R.; Davies, G. B. H. (2009). “Biodegradable and compostable alternatives to plastics.” Philosophical Transactions of The Royal Society B Biological Sciences 364(1526):2127-39. Available at: https://doi.org/10.1098/rstb.2008.0289. (Accessed 4 May 2022).

Similar Posts