Biodegradable plastics are here and are answers to our plastic wastage solution. Made from natural materials such as corn oil, orange peels, starch, plants, sugar and so on. These biodegradable plastics decompose faster than the usual plastic as it contains substances that attract microbes to decompose them.
Plastics are made from chemicals, which takes years to decompose. Even when melted, it releases harmful gases like carbon, and methane into the environment, polluting it. Biodegradable plastics do not contain these pollutants and are broken down by environment friendly bacteria.
Essentially, there are two main types of biodegradable plastic; Oxo-biodegradable plastic and hydro- biodegradable plastic.
This type of plastics are made using the same technology as conventional plastic; with very little additional cost involved. It is made from fossil fuels, oil and natural gas, with only a small amount of pro-degradant additive added in the manufacturing process that changes the degradation process of plastic. Such type of plastic is consumed by bacteria and fungi to a point till the material has biodegraded into CO2, water and humus. It does not leave fragments of petro-polymers in the soil and have in fact passed the usual eco-toxicity tests, seed germination and organism survival.
Oxo-biodegradable plastics are currently made from naphtha, which is a by-product of oil refining. The time it takes for Oxo-biodegradable products to degrade can be ‘programmed’ at the time of manufacturing process. It takes a few months to years to degrade, but does not release harmful gases such as methane or nitrous oxide.
Hydro-biodegradable plastic is made from plant sources such as starch and the degradation is initiated by hydrolysis. These types of plastic degrades faster than Oxo-biodegradable plastic and can be industrially composted. They are temperature resistant, and the only bioplastic that will decompose in both soil and water. Polylactic acid or PLA is the most commonly used bio-degradable plastic. These too do not emit potentially harmful methane gas at any stage.
A third category of bio-degradable plastic is photo-degradable that reacts to ultra-violet light. But requires initial Oxo-degradation, failing which the bioplastic will not degrade in other environment.
Some other biodegradable form of plastics currently under research are plastics made from sugar, banana peel, avocado, shrimps, waste frying oil. Biodegradable plastics are into food packaging, shopping bags and many other products. Bioplastics have a lot of potential to be composted thereby decreasing the landfill burden and a bigger role in environment sustainability.