All You Need To Know About Bioplastics:
The Chief minister of Tamil Nadu Mr. Palanisamy on June 5 (aptly The World Environment Day ) announced a much-needed ban on all plastic products. This ban however late and biased is a good start.
With just a day to go before the ban kicks in, the suggestions for alternatives that the government has issued are far from feasible. Banana leaves and Earthen vessels seem far from plausible. These can never be mass-produced at the rate conventional plastics are being produced in industries before the ban.
One feasible way forward from this mess today is by bringing the so-called Bio Polymers into mass public consumption.
Before delving deep you must understand that just because something has the terms bio-, or organic- affixed to it ,doesn’t gain it any credibility.
People today have confused the terms bioplastic and biodegradable plastic to be synonyms. But they are not the same.
Also there is another controversy , concerning the compostability of bioplastics.
There are some stark differences between a bioplastic and a biodegradable plastic.
In general all materials are plastic to a degree. The ability of clay to mold into different shapes without breaking that gave us joy when we were young is because of its plasticity.
But the masses use this term (plastic), to denote the moldable class of polymers , and mostly to the synthetic ones. So today we only consider Petrochemical polymers as plastics. There are seven types of petrochemical polymers that people consider as plastics.
- Polyethylene terephthalate[PETE],
- High Density Poly Ethylene [HDPE],
- Poly Vinyl Chloride[PVC],
- Low Density Poly Ethylene[LDPE],
- Poly Propylene[PP],
- Poly Styrene[PS],
- Miscellaneous Plastics (polycarbonates,polylactides,styrenes,fiberglass,nylon…).
This above mentioned list covers most plastics that are considered ill to the Environment and to us. Among them PVC is called the POISON PLASTIC and you apparently know why. Its harmful when ingested and PVC fumes are said to release harmful cancer inducing agents called dioxins.
IUPAC gives the following definition for biobased polymers,
“Biobased polymers derived from biomass or issued from monomers derived from the biomass and which, at some stage in its processing into finished products can be shaped by flow.”
IUPAC suggests the usage of the term biobased polymer since the term bioplastic is misleading. Not all bioplastics are biodegradable.
IUPAC says that “ Bioplastic is misleading , because it suggests that any polymer derived from biomass is environment friendly.”
In bioplastics the Carbon, hydrogen and Oxygen come from renewable bio mass sources like Vegetable oils, corn, soy, sugarcane, whereas conventional plastics get their Carbon, Hydrogen and Oxygen from petrochemicals.
- Bioplastics are plastics where the C, H and O in it’s chain come partially or completely from renewable resources,
- They are derived from the biomass (vegetable oils,corn,etc..) directly, or by artificial polymerization of monomers derived from the biomass,
- They should be shape-able by flow (plasticity) in some stage of their manufacturing process,
- The term bioplastic is quite misleading and not all bioplastics are biodegradable and environment friendly.
BIOPLASTIC VS BIODEGRADABLE PLASTIC:
Biodegradability of a material is its susceptibility to be eaten (broken down) by a micro-organism and released into the environment as harmless CO2, H2O, biomass and inorganic compounds. The only catch is the rate(speed) of biodegradation should be in par with natural compostable materials ,(else it would be meaningless, since conventional plastics are also degradable in a few hundred years).
Some organisations and countries have now started to use the term compostability instead of biodegradability specifying the factory compostability of a material.
Compostable Bioplastics are degradable in 6 months in an industrial composting facility. So it is not the source of the plastic that matters only its compostability is important. A bioplastic can be as much a burden as a petroplastic when its compostability is not good. So not all bioplastics are superior to conventional plastics. People must be aware of this to protect themselves from getting baited into buying bioplastics equally dangerous as conventional plastics.
Also without proper composting centres these compostable bioplastics too can become a burden on the environment since they may take years to degrade outside a composting facility.With the rate at which we are generating wastes this sure is trouble.
But an Indian company Envigreen has patented a new starch based raw material which doesn’t require a factory composting facility and thus is degradable in normal environment.
Their website says
“Envigreen is not just a brand, it is a Green Technology. Envigreen’s products are made from natural starch, vegetable oil derivatives and vegetable waste. These products are non-toxic to the environment, animals and plants. Envigreen contains no conventional plastics at all. Envigreen products have an electric dissipative feature (suitable for electronic wrapping) along with anti-static feature-dust repellent, oxygen barrier-corrosion prevention, oil/grease resistance. It dissolves in hot water (80 degree Celsius) and softens in water at room temperature.”
CHALLENGES TO BIOPLASTICS:
The main challenges the bioplastic industry faces are that
- They are made from plant resources which is price-wise not competitive with fossil fuels,
- Also at present most indian manufacturers import the raw materials (Poly Lactic Acid, Poly Hydroxy Alkanoates) used to make bioplastics which adds to the price burden.
Like the phrase NEED IS THE MOTHER OF INVENTION,
The Indian startup environment is coming up with new ideas to bring this price gap down. Now it is in the hands of our policymakers to nurture this startup environment.
SOME INDIAN STARTUPS IN THE BIOPLASTIC INDUSTRY:
- Envigreen -Bangalore based,
- Greendiamz Biotech-Ahmedabad based,
- Ecolife LLC-Chennai based,
With the amount of plastics having accumulated in the past 100 years there is much room for more such innovators..
- Priyanka Pulla- article on The Hindu dated 30/12/2018,
- Biodegradable plastics-Wikipedia,