Adding value to polymer waste through recycling

Plastics have become a necessity in our daily lives. The wide variety of applications of plastics has made them indispensable but at the same time plastics are non-biodegradable and a source of continuing pollution. The recycling and harmful issues of plastics have been discussed to death.
 
However, it is a fallacy. Plastics have changed the way of life - the little bit of hygiene in India can all be attributed to plastics - from hospitals to restaurants to packaging. The problem lies in collection and recycling. Most of the plastics wastes are not recycled in India and it can be seen scattered all over our towns and cities, polluting the surrounding land and water resources. Plastics account for nearly 16% chlorine in the environment and have over 54 carcinogens. Polythene bags for disposal if burnt irresponsibly releases highly toxic gases like phosgene, carbon monoxide, chlorine, sulphur dioxide, nitrogen oxide, besides deadly dioxin.
 
ALSO READ: Improving performance of plastic products using glass microspheres sustainably

For achieving substantial diversion of waste from landfills, there is an urgent need for efficient and practical method for collection of waste. Although collection is labour intensive but segregated collection leading to greater resource recovery can render this activity not only cost-effective but environmentally and economically sustainable. So the solution is a proper collection method followed by recycling. Banning plastics will make things worse and send us hurtling back to stoneage.
 
Recycling, a practical solution
With the economic growth in India, the purchasing power of the people has increased substantially. To add to it there is an ever increasing Indian middle class. This has given a great boost to the automobile and white goods segment. These sectors have seen large multinational players foray into the Indian market. They use high performance engineering polymers which when recycled do not have the same mechanical properties and are not suitable for use by the industry.
 
There are a number of challenges faced by the recycling industry ranging from changing life style patterns to increase in population along with lack of awareness and acceptance for the recycled products. The major challenges which hamper the comprehensive utilisation of polymer scrap/waste include:

• Low competitiveness of individual enterprises
• Lack of industry concentration
• Lack of leading players
• Lack of social acceptance and recognition for the recycler

Overcoming technical challenges
Besides, recycling of plastics has several technological challenges. The presence of other materials like aluminum and metals in the plastic waste makes it difficult to recycle - compatibilisation is difficult because of the presence of these and a combination of different polymers in the waste.  The properties of plastics deteriorate after recycling; therefore cannot be used to replace virgin polymers.
 
ALSO READ: Efficient cooling system improves productivity in plastic moulding

The focus has to be on innovation to create additives that can help rework polymer waste to be re-used in the production of quality products. Compatibilisers help bring the properties of the mixed polymer waste to virgin levels. Such specialised additives also help compatibilise the mixed waste. They not only compatibilise immiscible polymers well but also enhance filler dispersion into the polymer matrix thereby giving enhanced properties.
 
Recycling of packaging waste is another area of major concern for the society as a whole. The recycling of mixed plastics films is not easily done as it contains mixture of polar and non-polar plastics materials. These contain metal coatings (like aluminum), incompatible laminates such as PET, PE, Nylons, inks and adhesives. There are specialty polymers available in the market which help in overcoming the above stated problems associated with plastics film recycling.
 
In the automotive industry, there is a growing move towards reuse and reprocessing of plastics for economic, as well as environmental reasons, with many praiseworthy examples of companies developing technologies and strategies for recycling of plastics. Since economics of the polymer scrap is an important concern, these speciality additives give an edge in the competitive manufacturing world to recyclers of engineering polymer scrap. It enables the recycler to bring materials to virgin levels.
 
Focus on recycling
The society needs to accept polymers as a given, given our way of life today. The focus has to shift from banning polymers to using them intelligently and responsibly. It also needs to shift to developing proper methods for collection and disposal of waste and developing technological solutions to handle the collected waste. Only a few companies in India have been actively engaged in finding solutions to environmental problems posed by polymers and the special additives required to get the desired properties. Companies engaged in plastics and polymers processing and those using these products, need to come forward with implantable solutions, rather than just sponsoring conferences on recycling!
 
ALSO READ: Armed with technologies Indian plastics industry ready for global competition

Sustainable polymer waste management needs to be based on the waste management hierarchy of, firstly, avoiding generation of waste, followed by reducing, reusing, recycling, recovering, treating and responsibly disposing waste. Waste management envisages an integrated approach, encompassing technological, policy, administrative and legal actions to address the challenge of waste management in India.