Have you ever wondered how to change a polluted environment?
Most times, we see plastics littered by the roadside and wonder if these plastic containers can be used in an environmentally friendly way.
China is one of the countries with the largest plastic manufacturers and consumers in the world. Japan also has a plastic waste management problem resulting mostly from the purchase of ice tea, which requires the usage of plastic cups.
And ever since China stopped collecting Japan’s plastic waste, there has been a need for solutions. This is where biodegradable plastics come in.
A biodegradable plastic has the capacity of being decomposed by biological activity, mostly by microorganisms. Biodegradation usually occurs in an airtight area (anaerobic environment); it doesn’t use oxygen.
This plastic is built of molecules that can decay essentially but slowly. This indicates that it is made by recycling traditional plastic. It can take years to decompose if the procedures are performed wrongly.
How to Identify Biodegradable Plastics
You might be wondering how to tell regular plastic from biodegradable plastic? That’s very simple.
If the plastic can degrade in water, carbon dioxide, and biomass within a specific time-lapse, it can be considered a biodegradable plastic. This property is an unvarying process that can be tailored particularly for controlled decomposition under biological systems.
Brief Discussion on Biodegradable Products
Do you know that traditional plastics take one thousand years if left to decompose on their own?
Conversely, biodegradable plastics decompose in a matter of weeks (twelve weeks on average). They can break down their organic matter into microorganisms. And are decomposed safely and effectively.
They are defined in terms of the chemical composition of the plastic.
Currently, some of the famous commercial biodegradable products available are starch plastics, soy plastics, lignin plastics, and cellulose plastics.
The starch plastic is mainly made from farm products like corn, wheat, and potatoes.
Of all farm produce, corn is the most used. This is because it is cheap while starch is very costly. Many companies are beginning to indulge in biodegradable plastics because they’re eco-friendly.
Starch-based plastics are created from hydro-biodegradable plastics.
Lignin and natural fiber reinforcement plastics decompose similarly to starch-based plastics. Lignin is made from oil refined or petroleum-based products while natural fiber reinforcement plastics are made from biodegradable plastics.
In other for these bioplastics to be termed as “biodegradable plastic”, they have to be confirmed by the ASTM standards set down to ensure that the properties can be handled in an industrial composter. The ASTM number for compostable plastic is D6400.
Types of Biodegradable Plastics
Most biodegradable plastics are a fusion of organic materials (cellulose and starch) and chemical compounds that decompose into methane, biomass, water, CO2, and mineral salt.
There are two classes of biodegradable plastics namely oxo-biodegradable and hydro-biodegradable. In both, decomposition begins with a chemical procedure followed by a biological procedure.
They have their foundations from plant-hydro-biodegradable plastics and petroleum-oxo-biodegradable plastics. Both classes give off carbon dioxide as they decompose; hydroplastic can also give off methane (CH4).
1. Oxo-Biodegradable Plastics
Oxo-biodegradable plastics are made by adding a small piece of a fatty acid compound of explicit transition elements to ordinary plastic.
The plastic does not emit methane when decomposing, unlike hydro-biodegradable plastic. It is mostly used and recycled alongside traditional plastic. Its products are durable and can last for up to five years and more if kept away from direct sunlight or heat.
The products are made by blending particular additives into traditional plastics such as polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyvinylchloride at the moment of conversion into the final stage.
The oxo-biodegradable plastic is sometimes valued at the same price or lesser than traditional plastic. It also has the same strength and weight as traditional plastic. It isn’t prone to leaks (leak-proof).
The plastic is usually made from an oil-refinery by-product. It can be decomposed anywhere, either on land or sea.
This type of biodegradable plastic is safe to come in contact with edible products. It uses no fertilizer or water during its production process. The demand for oxo-biodegradable products does not affect the price of fuel for cars. It is dormant in landfills and doesn’t emit methane while being incinerated. It is compostable in a vessel.
The decomposition is kicked off by sunlight and there’s no known duration for when the degradation starts. It takes about two years to decompose.
2. Hydro-Biodegradable Plastics
Hydro-biodegradable plastic is mainly produced from plants; the process begins with hydrolysis. It is decomposed by splitting the bond of the hydrogen cation and the hydroxide anion of water. This decomposition is faster than in oxo-biodegradable plastics.
It is the only biodegradable plastic that can degrade in a microbial area. Its temperature-resistant feature helps to speed its decomposition process.
This plastic is costlier than traditional plastic and is safe to come in contact with food. Its demand affects the price of foodstuffs for animals and humans because it’s mostly gotten from farm produce.
When incinerated or buried underground, it emits methane.
The plastic is weaker, thicker, and heavier than traditional plastic. It is compostable and not suitable for high-speed machinery. It is made from starch and isn’t leak-proof.
The duration for decomposition cannot be controlled; there is a contingency of GM ingredients. This plastic cannot be recycled.
Biodegradable Plastics & Compostable Plastics
Compostable plastics are also commonly being used. They are used alongside biodegradable plastics and are sometimes mistaken for biodegradable plastics.
Biodegradable and compostable plastics are eco-friendly designed plastics that can decay after an ASTM-influenced estimated time frame.
Not all bioplastics are biodegradable. Some are compostable and can only decay into fragments but not totally out of sight.
Let’s differentiate between the two plastics for a better understanding.
Differences between Biodegradable Plastics & Compostable Plastics
- Biodegradable plastics break down slowly over the estimated time of twelve weeks into microorganisms that are invisible to the naked eye. Compostable plastics, on the other hand, decay just the way leaves decay. There is no estimated time of decomposition
- Biodegradable plastics are not always compostable but compostable plastics are biodegradable in composting conditions
- Compostable plastics are decomposed plastics broken down in a particular environment. Biodegradable plastics are decomposed by burying them under land or sea
- Compostable plastics require certain conditions for decomposition to occur while biodegradable plastics are degraded using certain methods
- Biodegradable plastics break down naturally. They harness microorganisms present in an environment to rid the planet of plastics until they’re gone out of sight. Compostable plastics, on the other hand, have to break down in a composting environment. They have special requirements and treatments to decompose properly. They’re biodegradable but aren’t biodegradable products
The Use of Additives in Decomposition
Additives are usually added to composters to aid the sluggish process of decomposition of biodegradable plastics.
Some oxo-biodegradable plastics use Cobalt for speedy decomposition when the landfill process is used. Some use a mineral salt to speed up the process. This results in very small pieces of plastics that are no longer visible to the naked eye and pollute the environment.
Why Retain Traditional Plastics?
You might be wondering why not use biodegradable plastic since they are eco-friendly? The reason why we cannot do away with traditional plastics is that biodegradable plastics are the recycled version of traditional plastics.
Biodegradable plastic is the way to the future. Its rapid decomposition is eco-friendly; it decomposes and becomes out of sight in weeks. This method of producing plastic will aid our environment. Biodegradable plastics should be used and encouraged.