What is Bioplastic?
Updated: Apr 18, 2020
Bioplastic is nothing but a plastic, which is produced from natural renewable source and/or biodegradable.
It looks similar to conventional plastics and difficult to differentiate by the naked eye.
Why do we need Bioplastic?
The main idea behind the invention of plastic was to have a cost-effective material that cannot be affected by water/moisture, bacteria, sunlight, weather, etc. That means it does not degrade in any condition of the surrounding atmosphere.
So to say, our current problem of plastic was the biggest advantage when it was invented.
It does not degrade, hence it will stay in the environment for thousands of years; creating pollution and other harmful effects, as it is derived from petrochemical. Here comes the challenge, how to overcome the problem, which actually is the biggest advantage of it.
At first, recycling was introduced to stop piling up the discarded plastic. A study says, only 9% of plastics were recycled in 2018, even after imposing so many rules and regulations to stop creating plastic pollution. It depicts that there are certain limitations for recycling and we still need more options or ideas to overcome the problem.
Meanwhile, bioplastic was invented and introduced in the market. It carries the advantage of not being affected by the surrounding atmosphere, at the same time it is manufactured from natural renewable sources and can be composted/degraded under certain conditions to send it back to nature; that creates the circular economy. In short, it solves the problems of pollution by disappearing completely in the environment by biodegradation.
Same time, bioplastics can withstand environment and weather effect for a specific period of time to make it useful in real life.
In addition, it does not create any harmful effects, as it is derived from renewable natural sources; moreover, it can also be recycled by converting it back to the monomer and polymerizing.
Let’s understand it by carbon life cycle,
The carbon cycle for the Petrochemical industry takes million years to complete, It takes million years to maintain the consumption vs conversion ratio. Whereas bioplastics can be converted into water, carbon dioxide and compost in 1 to 8 years of time (depends on the composting environment), that will be consumed by plants naturally and generates agricultural products. Again, agricultural products can be converted into bioplastics and create a circular economy in nature.
Types of Bioplastics
1. Bio-based & Biodegradable plastic
2. Bio-based & Non-degradable plastic
3. Petrochemical-based & Biodegradable plastic
4. Compostable plastic
5. Starch blends*
6. Oxo-degradable plastic*
*not really bioplastic
1. Bio-based & Biodegradable plastic:
This type of bioplastic is really impactful to cope up with the plastic pollution problem. It is derived completely from renewable feedstock (agricultural product). Once discarded, it converts into compost, water & carbon dioxide by degradation in a natural environment (takes more time) or industrial composting site (normally 180 days for 90% degradation).
Example: Polylactic acid (PLA)
2. Bio-based & Non-degradable plastic:
It is used by most of the brands depicting as sustainable material worldwide. It is derived from renewable feedstock (agricultural product), but it does not degrade in any specific timeline. It behaves the same as normal plastics and takes million years to disappear. The biggest advantage of this material is that it is bio-based and hence, it does not give stress on petrochemical resources.
Example: Bio-PET, Bio-PE
3. Petrochemical-based & Biodegradable plastic:
The advantage of this material is that it is degradable in natural environment or special composting site. But, it has to be dependent on petrochemical resources. It generally is being mixed with PLA to improve the properties for specific applications.
4. Compostable plastic:
Compostable was brought by nodal agencies working on these segments. To maintain a specific standard for industries for being written that it is not harmful to the environment, the definition and standards came into the picture for showing any product as a compostable product. It has to follow ISO 17088 (for India), EN 13432 (for Europe) and ASTM D6400 (for the USA) to be recognized as compostable. According to standards, the material will get disintegrated within 90 days and biodegrade at least 90% in 180 days in a standard composting facility. Remaining 10% solid will be valuable compost/biomass and water, which has no harmful content and can be used in gardening or farming. All compostable plastics are biodegradable plastics.
5. Starch blends:
Generally, this material is water-soluble and cannot withstand the moist environment. By definition, it is not polymer/plastic and bioplastic. Its application is limited to extrusion films only. The biggest advantage is that it has a very fast degradation rate without any specific environment comparatively, at the same time it is the disadvantage of notwithstanding weather effects. It has a very short life span.
6. Oxo-degradable plastic:
It is not at all a bioplastic. It has created a myth around the world that it is a bioplastic and not harmful to the environment. Whereas, it is a conventional plastic with an additive, which makes it quickly fragmented into smaller and smaller pieces, creating microplastics. It does not break down at a molecular level like compostable or biodegradable plastic. It actually increases the harmfulness of the plastic by creating microplastics, which can easily pollute the air, groundwater, food, etc. and have the potential to reach in human or animal bodies, causing extremely harmful effects to humans and animals.