Biodegradable Plastic – A Potential Substitute for Synthetic Polymers
In recent years, there has been a marked increase in interest in biodegradable materials for use in packaging, agriculture, medicine, and other areas. Polyethylene, polyvinylchloride, polystyrene are largely used in the manufacture of plastics which are not degradable for several hundred years. But the point is that even though they take thousands of years, they are eventually decomposed which means that there exist some microbes which can degrade plastic. If these microbes are genetically manipulated and made to degrade polythene (plastic) at a faster rate, it would be a novel technique to solve the global waste crisis. Example: Streptomyces sps.
While these are various techniques to degrade the synthetic plastics, there are some methods to produce biodegradable polymers which can be easily decomposed by microbes on disposal. These polymers are made out of naturally occurring materials such as starch, cellulose, lactic acid and fiber, extracted from various types of plants. Biopolymers limit carbon dioxide emissions during creation, and degrade to organic matter after disposal but this does not mean that all the biopolymers should be completely biodegradable. However, microbial consumption of polymers is available through addition of hydrophilic type additives onto the surface of the polymer chains. These types of additives are readily available and are used worldwide. For example, Polylactic acid (PLA) is a 100% compostable biopolymer which can fully degrade above 60°C in an industrial composting facility.
Biodegradable plastics are scientifically sound, and a novel idea, but the infrastructure needed to commercially expand their use is still costly, and inconvenient to develop. Time is of the essence for biodegradable polymer development, as society's current views on environmental responsibility make this an ideal time for further growth of biopolymers.