Is it possible to make Green-Plastic? Years back when I was getting acquainted with outlook version of email , a friend of mine doing graduation in Germany mailed me saying that if he had to buy packed food , he could return earlier used container to get the discount else he would end up paying more. Even with plastics not being so ubiquitous at that time in India and with many of us still using glass and metal containers in food packaging, I was very thrilled with this compelling idea of reusing and recycling plastics and not throwing in a heap of waste – which would take – may be decades of years to shred into the fine particles in soil. So a green-plastic actually means recycling one to stop soil and water pollution.
With the growing population, urbanization, improved standard of living, dependence on processed food, aesthetic appeal coupled with affordability of plastics and our quest for making durable products, we have ended in creating huge piles of waste plastics, equal number of land burials with the want of a suitable mechanism to control this menace. Although India takes pride in recycling much of the plastics as compared to developed nations, sore sights of plastic waste strewn all over the roads reminds us of the most acute need to use the plastics with conscience and responsibility in a sustainable manner. Other ways of tackling waste includes incineration that can lead to the greater environmental pollution and hazard to the human beings as well as animals.
In addition to the use of “Recycle-Reuse-Reduce” strategy professed and driven by many organizations,multiple ways have been adopted to tackle this porblem. However it is not only the waste created by the end of life cycle of the product but the entire cycle of going from cradle to grave of product development involves processes that pose various challenges such as depleting fossil fuel, energy of conversion, transportation and resulting stress on environment due to these processes. Some of these challenges are addressed by various green initiatives, e.g. part of the raw materials based on fossil fuel is replaced by renewable resources based on plants or use of completely biodegradable polymers wherever possible. While the former approach may not necessarily result into completely biodegradable materials unlike the parent plant resource, the second option might be challenging in terms of achieving properties comparable to those of synthetic polymers.
Plant based monomers such a lactic acid, various glycols, glycerol , long chain fatty acids etc have been used in making plastics that are commercialized by various companies. Polymers entirely based on plants such as cellulose, starch, rubbers etc have been used traditionally in many applications. Both these approaches can address the dependency on fossil fuels to some extent. Another approach adopted by many companies is to use plant based products such as natural fillers like jute, hemp, kenaf, flax etc along with synthetic polymers for many applications. This approach goes back to 1930s when Ford company developed hemp based composite in automotives. However there remains a challenge in using such composites to larger extent due to various factors such as processing conditions, compatibility, thermal and mechanical properties required for the end-use application.
Green-plastics encompass various types of plastics that are environmentally friendly, those which leave lower carbon dioxide footprints or those that are completely biodegradable.
Awareness about the environmental concerns coupled with some of the regulation and mandates given by the government for replacement by green components, many automotive OEMs have been actively developing and implementing such green initiatives. Packaging is one area where the volume of used plastics generated is more. Green plastics holds a key promise and can bring a revolution in packaging industry if the judicial product development is done to meet the shelf life requirement along with other properties such as permeability, transparency, aesthetics, thermo-mechanical properties and easy processibility can be met for the required application.
In the area of biomass conversion to useful building blocks for producing plastics, a lot of advancement is done in the area of identification of right resources, catalyst, process to improve the efficiency of conversion. In order to realize the full potential of this route, various factors such as cost involved in the transportation of biomass from the farms to the factory, economic viability to make the monomers available if not lower but at least at the same price as that of synthetic counterpart will need to be tackled. In the area of biodegradable plastics newer mechanisms and various benign catalysts such as suitable soil microbes are explored to fine-tune the degradation kinetics as per the requirements. With all these global efforts, at least we are taking a very tiny step to pass on this beautiful world sans plastics garbage to the future generation. Greater consumer awareness about various issues involved in irresponsible handling of plastics is also the need of hour.
Meanwhile I am hoping that someday I shall be free of guilt of not having to leave my carbon footprints at least in the form of plastics that clogs the drainage and waterbodies, suffocates the fertile land, kills the pet and make every site eyesore.