City scientists have developed a kind of plastic that can decompose in two months when exposed to sunlight.
A three-member team from the Institute of Chemical Technology, Matunga, has developed oxodegradable polymer by combining plastic granules (most common in packaging) with a catalyst, which helps plastic break down into a smaller chains in the presence of sunlight.
Regular plastic is non bio-degradable, which means it is not consumed by bacteria present in the soil. "Plastic does not degrade for years because it is chemically inert. Indiscriminate use of the polymer resulting in litter affects the environment and pollutes the earth," said professor RN Jagtap, head, department of polymer and surface engineering, who is a part of the study.
The research team, which has been working on the project for four years, has derived the catalyst from metals. The catalyst promotes the oxodegradation of plastic. Stating that the catalyst had not been derived from toxic heavy metals, the researchers refused to divulge the metals from which the catalyst is derived as it is in the process of applying for a patent for the technology.
The team processed the catalyst with synthetic polymer granules to manufacture transparent plastic films. When discarded, the additive will cause the plastic to degrade in sunlight.
"The drop in molecular weight gives micro-organisms (present in the soil) access to carbon and hydrogen, making plastic a nutrient for bacteria and fungi to feed on that results in complete degradation," said Jagtap.
The team will undertake field trials after the monsoon season to check if oxodegradable plastic crumbles and gets eaten up in two months
"Oxodegradable plastics degrade in the presence of ultraviolet rays and heat and can also be recycled with normal plastics. The disadvantage is that there are certain metallic elements that carry risk of environmental pollution. Hence, their nature and level of use are to be properly controlled," said professor Anil K. Bhowmick, director, Indian Institute of Technology-Patna who is on the editorial board of Journal of Applied Polymer Science.