In this article we will be discussing the concept of biodegradable plastic, its existence, its composition and characteristics, its impact on the environment. We will also be shedding light on how it is manufactured and how much different it is from conventional plastic.
Is biodegradable plastic myth or fact?
Biodegradable plastic is not a myth. It is a fact. Biodegradable plastics are a type of plastics that can be readily decomposed by the microorganisms into water, carbon dioxide and biomass.
They are mostly manufactured from the raw materials which are renewable, petrochemicals, micro-organisms or a combination of all three products.
Even though the term biodegradable plastic and bioplastic may sound similar, they are different when it comes to properties. Not all bio-plastics are biodegradable in nature and do not get decomposed into biomass.
What are biodegradable plastics made of?
Biodegradable plastics are made in such a way that they can be easily broken down by microbes present in the soil, the ultra violet radiations, water and wind. They are primarily composed of renewable raw materials, or organic materials such as soybeans, corn oil, orange peels etc.
In industries biodegradable plastics are manufactured in the same way an ordinary plastic is manufactured. The only difference is that the raw materials used in the manufacturing of biodegradable plastic are different.
Biodegradable plastics are mostly made from traditional petrochemicals in order to break them down faster. Additives are added to them in order to increase the rate of decomposition.
Moisture also enhances the rate of decomposition. When the biodegradable plastic is exposed to UV light they end up breaking down much faster.
What are biodegradable products?
A biodegradable product includes substances and materials that can be degraded by natural factors such as:
- UV radiation
Biodegradable products include food materials, waste from the kitchen and various other natural wastes such as animal feces or plants. Microbes along with temperature, oxygen and radiation break down these biodegradable substances into their simpler forms which eventually become a part of the soil.
The process of biodegradation can be rapid or slow depending on the type of waste. The environmental risk posed by biodegradable waste is extremely less.
How does the process of biodegradation occur?
The process of biodegradation is initiated by bacteria and fungi. These organisms release their enzymes in order to break down the substances.
This process requires suitable and optimum conditions which include perfect temperature, moisture, type of soil, pH and oxygen level of the soil. Enzymes can be used to increase the rate of this biodegradation process.
Biodegradable waste is decomposed by the process of composting stimulated via microorganisms. However, the biodegradable waste needs to be managed properly. If they are not managed properly they will have an adverse impact on the environment. For instance production of landfill gas from methane emission from anaerobic fermentation.
What are different types of biodegradable plastics?
There are several different types of biodegradable plastics. Depending on the type of chemicals used to make them they are categorized into different types which are as follow:
Polyhydroxyalkanoates: polyhydroxyalkanoates are commonly known as PHAs and are naturally produced by different microorganisms such as bacteria. The biosynthesis of PHAs are done by making the microorganism deprived of different nutrients and exposing it to excessive carbon sources.
Polylactic acid: polylactic acid or PLA is made from renewable biomass. The sources of renewable biomass are normally fermented plant starch which include sugarbeet, corn, sugarcane and cassava. Even though PLA is considered as biodegradable in nature artificial conditions have to be applied in order to initiate the process of biodegradation.
Starch blends: starch blends are formed by mixing starch with plasticizers. Since starch is extremely brittle in nature and cannot retain a structure, plasticizers are added to retain the structural integrity of the product. Starch is biodegradable in nature but some of the plasticizers are not, therefore the biodegradability of starch blends depends on the type of plasticizer used.
Cellulose-based plastics: cellulose based plastics are derived from cellulose esters and celluloid.
Lignin-based polymer composites: lignin-based polymer composites are made from aromatic polymers. These aromatic polymers are biodegradable in nature and reactive to various functional groups of chemicals present in the soil. These polymers are extremely elastic and viscous and are eco-friendly.
What are the benefits of biodegradable plastics?
Biodegradable plastics have numerous benefits. Biodegradable plastics are much easier to recycle as compared to conventional plastics.
They take extremely less time to decompose and are recycled via organic process. biodegradable plastics do not contain any toxins and can be used as a compost or provide energy to biogas.
biodegradable plastics consume very less energy when they are being manufactured. The manufacturing process of biodegradable plastics removes all the processes of finding, accessing and transporting the hydrocarbons. This eventually results in using very less fossil fuels and less environmental pollution.
biodegradable plastics reduce the amount of waste produced. Depending on the method of disposal and the products used to manufacture biodegradable plastics they can be decomposed within months.
Biodegradable plastics are easily broken down by the different environmental factors. The broken down compounds are either absorbed by the soil or converted into compost.
biodegradable plastics utilize very little petroleum or no petroleum at all. Most of the biodegradable plastics are made from natural ingredients. This means when there is no utilization of petroleum, there will be no emission of greenhouse gasses and the entire process will have a positive impact on the environment.
biodegradable plastics have the ability to make the soil fertile because they are made from natural organic materials. These materials once decomposed enhance the soil’s water and nutrient retention. Biodegradable plastics once decomposed can also help in the growth of healthy plants free from pesticides and chemicals.
Biodegradable plastics do not release harmful toxins while they are being decomposed unlike conventional plastics which are made from synthetic products. When synthetic plastics are broken down by environmental factors they end up leaching harmful toxins into the soil making the soil poisonous or dead. These toxins also harm marine life if they travel through the waterways.
Using biodegradable plastics means there will be no consumption of the lethal products by the soil and the environment will be sustained.
Biodegradable plastics are broken down by bacteria which occur naturally making them cost effective. This means the cost used to decompose conventional plastics can be decreased or can be saved entirely.
Biodegradable plastics are easier to manage. When they are decomposed in the soil the waste is relatively easier to manage. The amount of fuel and energy in this process is also zero making biodegradable plastics a much more sustainable option.
What are some of the disadvantages of biodegradable plastics?
Biodegradable plastics have few disadvantages. Even though the advantages of biodegradable plastics can outnumber the disadvantages, it is important to shed light on them as well.
There is always a risk of contamination while manufacturing biodegradable plastics because they are derived from natural sources such as corn and soybeans. The crops are normally sprayed with pesticides and the chemicals can be easily incorporated into bioplastics.
Biodegradable plastics are cost efficient but the process of manufacturing biodegradable plastics is costly. The processors and composters used to make biodegradable plastics are relatively more expensive than the machinery used to make conventional plastics.
If biodegradable plastics are not disposed of properly there can be a potential risk of contamination with the traditional plastics. Due to lack of awareness when it comes to the decomposition of biodegradable plastics they end up getting mixed with the traditional plastics and the potential of being reused and recycled gets decreased. This ends up adding more volume to the landfill waste.
Biodegradable plastics have the tendency to produce methane in the landfills. Methane is severely potent when compared with carbon dioxide according to research. It has the tendency to absorb heat and this eventually plays a part in climate change.
biodegradable plastics even though are derived from natural sources such as crops etc but are raising concerns when it comes to the management of crops. With the increasing demand of biodegradable plastics the crops are becoming scarce and are raising issues relevant to food security.
There is a possibility that biodegradable plastics may contain metals. High levels of cobalt and lead have been found after the decomposition of biodegradable plastics.
Biodegradable plastics demand to be disposed of with caution and care making the entire process tedious and time-consuming. If they are disposed of properly, the entire process of decomposition becomes ineffective. Most of the biodegradable plastics require water in order to be decomposed properly and facilitate the process of decomposition. If there is no water available, the process of biodegradability is hampered.
What are some uses of biodegradable plastics?
biodegradable plastics have quite a few uses:
- They can be used as shopping bags. Biodegradable plastics shopping bags are compostable and can be used to carry several items.
- Biodegradable plastics are also being used to make screws, pins, material for pills and capsules.
- They can be used to make disposable catering wares.
- biodegradable plastics can also be used to make jars, pens, pencils etc.
The concept of biodegradable plastics is a fact not a myth. Biodegradable plastics are eco-friendly and sustainable for the environment. They serve the environment in numerous ways such as acting as a compost, reducing greenhouse emissions and carbon footprints, however they do have few of the disadvantages. Biodegradable plastics are not cost friendly when it comes to manufacturing. Few of the companies also add synthetic products in the manufacturing of biodegradable plastics to enhance their characteristics. Once these biodegradable plastics are subjected to decomposition, they result in the release of toxins.
Frequently asked questions, “is biodegradable plastics a myth or fact?”
How long does it take for the biodegradable plastics to be decomposed properly?
The rate of decomposition of biodegradable plastics may vary. This all depends on its composition and manufacturing. Most of the biodegradable plastics take up to three to six to be decomposed completely.
How long does it take for the conventional plastics to be decomposed properly?
Conventional plastics take up to 1000 years or more to be decomposed completely and that too if they are subjected to artificial conditions otherwise most plastics are everlasting.
What is the difference between biodegradation and composting?
Biodegradation is a process which can occur anytime in the environment irrespective of the environment conditions. On the other hand composting is the process which is only carried out in specific environmental conditions. Compostable products are always biodegradable while biodegradable products are not always biodegradable.
How will biodegradable products impact the environment if used frequently?
The impact of biodegradable products on the environment if used frequently will be positive. After undergoing decomposition, biodegradable products produce a number of raw materials which are returned to the ecosystem.
The solid waste is converted into humus and is added to the soil. There can be somewhat negative impacts too, for instance the foul smell produced during the process of decomposition and possibility of acting as breeding grounds for disease vectors.
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