Biodegradable plastic bags are those that decompose by microbial action in nature.
To understand what led to the invention of biodegradable plastics, we need to start by understanding the world of plastics and the concerns surrounding them.
Plastics- Major Environmental Concern
Plastics are long chained carbon polymers. The synthetic composition of plastics makes them extremely resistant against microbial action. This is also the reason for plastics to be termed as non-biodegradable.
With the use of plastics in almost every industry, the concerns regarding their accumulation are being raised. Discarded plastic bags, in particular, have shown a tremendous increase in the environment. The accumulation of plastic bags is not just a physical and visual concern but a serious environmental concern too.
A plastic bag that carried your grocery would immediately be thrown away after use. However, it can take centuries for Mother Nature to discard it (break down the material)!
Disposing plastics is hard. Burning them creates toxic gas releases. Recycling is often not a convenient option too. That’s because recycling needs segregation of different types of plastics which go through different processes.
Plastics accumulated in the environment have grave implications on the soil, vegetation as well as wildlife. A big percentage of soil and water pollution results from unaccounted plastic bag dumping.
Additionally, the oceans also have had to bear the brunt of loads of plastic bags being discarded. The depletion of marine life and impacts on corals around the world has been a cause of worry for environmentalists.
With so much to worry about, plastics are still needed and used.
Why?
That is simply because they’re just too good to replace. The strength, durability and versatility of plastics make them a favorite with all industries.
A suitable alternative would hence need to come up with similar properties in addition to being environment-friendly.
Pressure from scientific communities as well as the public has led to the invention of eco-friendly alternatives.
Biodegradable plastic bags have evolved as an acceptable answer to the increasing problems of plastics.
The Alternatives Available
With the significant volumes of plastics making their way into the environment, coming up with eco-friendly alternatives has been a subject of research in the last few decades.
The environment-friendly variants of plastics are broadly categorized into three types:
Bioplastics
As the name suggests, bioplastics are made out of biological material that’s easy to decompose. The idea is to get the excellent properties of plastics substituted by a material that’s kinder to Mother Earth.
Corn Starch is a material that’s largely being used to manufacture bioplastics. Various types of bioplastics like PLA (Poly Lactide acid) are absolutely similar to their petrochemical counterparts.
PLAs have worked great for the food industry and are being used to make food containers, food wrappings, etc. Another positive factor about PLA’s is their compostable nature. Decomposing is as simple as putting them in the compost bin. A good number of bioplastics can break down into smaller fragments within a few weeks!
Biodegradables
You would have noticed the labeled plastic bags that supermarkets are using these days. The print usually says “biodegradable plastic bags” or “photodegradable” or “oxo-biodegradable plastic bag”.
What are these and how are they different from bioplastics?
Biodegradable plastics are those that decay in the presence of oxygen and light. Chemically, they’re just like their traditional petrochemical cousins. They just use certain pro-oxidant additives which makes them quicker to break down when the right conditions set in.
Biodegradable plastic bags are the most highly used alternatives to traditional plastic bags. However, certain concerns regarding their break down process have raised eyebrows in the ecological communities.
The anaerobic digestion of biodegradable plastic bags in the landfills or even in the oceans often does not happen as suggested theoretically. With the absence of the right temperature, light, and oxygen conditions, the breakdown fails.
An incomplete breakdown of biodegradable plastic bags can create smaller plastic fragments which are a threat to wild ad marine life.
Recycled Plastics
Recycling old plastics into new ones has been the easiest solution to the plastic problem. Recycled plastics are now being used to produce a wide range of products like outdoor furniture, gates, etc.
Recycling, however, has its own concerns. Recycling needs segregation at the source which is not always convenient.
Different plastics can have different molecular composition. This means that they have different recycling mechanisms too. Plastic bags, for example, may need a different process than plastic bottles and packaging materials.
Additionally, recycled plastics come at a lower grade and can not be used to create their parent products. This causes concerns over the usage of recycled plastic bags for usage in industries like food and hospitality.
Effectiveness of Biodegradable Plastic Bags
Now that we’ve understood the key types of eco-friendly plastics being commonly used, let’s dive in further.
Bioplastics appear to be clear winners, right? Well, not really. If you consider the fact that they’re made out of agricultural products, the picture isn’t as merry. Using Agri land for production of biofuels can significantly affect the food industry and the food prices around the world!
Biodegradable plastic bags are hence gaining popularity in the marketplace. Especially, the OXO- BIODEGRADABLE PLASTIC BAGS.
Other forms of biodegradable plastics include the hydro and the photo degenerating varieties. However, the absence of adequate water or light conditions causes an incomplete break down which is an environmental concern.
The oxo biodegradable plastic bags are arguably the best in terms of natural decay and minimal environmental impacts.
The oxo biodegradable shopping bags are similar in composition to the traditional petrochemical plastics. However, they come with the inclusion of a small amount of “pro degradant”. As insignificant as the step looks, it completely changes the behavior of plastic material.
The additives re-engineer the polyethylene and polypropylene polymers to make them biodegradable. These biodegradable plastic bags hence come with a limited life cycle. Once the programmed life is completed, the oxidation process starts, followed by degradation.
The additive included in the manufacturing process breaks down the molecular structure of the plastics to a stage that can be taken over by the bacterial world.
The microorganisms then create complete decomposition which turns the material to CO2, water and organic matter. A situation that’s easy for Mother Nature to take control of.
Oxo-biodegradable plastic bags can also be recycled using traditional techniques. The concerns over large scale waste accumulation are easily addressed. The eco-friendly plastic bags either get recycled through the usual channels or degrade in the environment through natural processes.
Interesting figures for Biodegradable Plastics
Following are some interesting figures and projects for biodegradable plastics and bioplastics:
- Global bioplastic production rose up to 1.5 million tonnes in 2011 from a meager 262,000 tonnes in 2007. It grew up to 2.11 million tonnes in 2018 and is predicted to go up to 2.62 million tonnes in 2023.
- In 2015, bioplastics and biodegradable plastics account for 1% of the share of total plastic production globally. It is expected that the figure will rise to around 2.5% by the year 2020.
- Packaging is the largest application of bioplastics and takes up around 65% of the total production.
- New fibers like PEF (Polyethylene furanoate) which are 100% bio-based are predicted to enter the global markets by the year 2023. The fiber comes with superior properties like heat resistance and is hence being eyed with interest by the food and packaging industry.
A sustainable future
While the multiple applications of plastics cannot be denied, it is true that the “green planet” is struggling to breathe.
The dumps of plastic bags have been steadily growing. The only promising alternative that science has come up with are biodegradable plastic bags. With their fast and natural break down capacities, they can bring forth a significant change in the current pollution levels.
Having said that, biodegradable plastic bags cannot alone solve the problem. The need to dispose them as per the guidelines is required. Additionally, no transition is possible without a change in consumer behavior. The responsibility to work towards a sustainable future needs to be shouldered together.
