“Plastic” is a general name given to a wide range of synthetic materials that are based on polymers. The world is drowning in plastic as the disposal of plastic is a global problem. They are nearly indestructible in natural conditions but are discarded worldwide on a large scale. Since the past 65 years, about 8.3 billion tonnes of plastics have been produced worldwide, which is equivalent to 10,000 Eiffel Towers or 35,000 Empire State Buildings. But only 9 per cent of all plastics get recycled, while the rest ends up as trash. About eight million tonnes goes into the ocean every year and the figure could rise to 500 million tonnes by 2020.
The world produce around 359 million metric tonnes of plastic each year. Plastic has an adverse effects on human health, marine life and the environment as it pollutes our soil and water as nature cannot address the amount of their disposal at a speed fast enough to prevent harm to living being.
About 60 per cent of the more than 8,700 million metric tonnes of plastic ever made is no longer in use, instead sat mostly in landfill or release to the environment. That equals over 400 Kg of plastic waste for every one of 7.6 billion people on the planet. One reason for this is that many plastics are not recyclable in our current system. And even those that are recyclable still go to landfill eventually. Plastics cannot be recycled infinitely at least not using traditional techniques. Most are only given one new lease of life before they end up in the Earth, the Ocean or an incinerators. We are all too aware of the consequences of plastics in the ocean and on land. However beyond the visible pollution of our once pristine habitats, plastics are having a grave impact on the climate too. There is a consensus that plastics are unsustainable materials. And yes, plastics are certainly an enormous problem, but they don’t necessarily have to be. The main issue is with our linear economic model: goods are produced, consumed then disposed of. This model assumes endless economic growth and doesn’t consider the planet’s exhaustible resource.
Most people believe that plastic recycling is severely restricted: that only a few types can be recycled at all. This is not surprising. The proportion of plastics that are recycled is minimal. The UK, for example, use five million tonnes’ of plastics each year and only 370,000 tonnes’ are recycled each year: that’s just seven per cent. But all polymers are, technologically 100 per cent recyclable. Some of them have the perfect cradle-to-cradle lifecycle: they can be used again and again to produce the same goods. Some plastics can be reused just as they are by shredding an object into flakes, melting it and reusing. Such recycled plastics may have lower mechanical properties compared to virgin plastics, because each time you melt and process a plastic, the polymeric chains degrade. But these properties can be recovered by mixing it to additives on virgin plastics. Example of successful industrial recycling includes PET (Poly ethylene terephthalate) which is used to make soft drink bottles and polystyrene. All of the rest can technically be reprocessed into new materials for different applications. In the final instance, any plastic waste can be shredded and used as filler for asphalt or be pyrolysed to produce fuel. The Japanese, Company “Blest Corporation”, already sells portable machine to convert domestic plastic waste into fuel in a simple affordable way.
The problem is that recycling much of this plastic waste is currently unfeasible and unprofitable. Polymers such as rubber, elastomers, thermosets and mixed plastics waste are comfortably labelled as “unrecyclable” by the recycling sector. But the amount of these materials all over the World is frighteningly large and keeps on growing and flagging the adverse effects of plastics at the recent International Plastic Bag Free Day, people resolved to eliminate plastic in their daily life. What if this plastic waste could be used to produce something useful to society? Many universities and entrepreneurs are attempting to do this. They asserted that the inventors of plastics should devise way to get rid of it. Enough is enough, said the environmentalists with their message: Reduce, Recycle and Don’t reuse. Suggestions raised at the meeting included managing plastic waste and utilizing it in a manner technologically feasible, economically viable eco-friendly and socially acceptable manner. In fact, Scientists and Engineers all over the World are researching and developing effective disposal and utilization of plastic waste in the construction of infrastructure projects.
Some recent developments has turned plastic into eco-friendly products and construction materials. Most solutions target mixed plastic waste and suggest applications. For example, several groups have developed building materials made of plastic waste. Plastics are strong, durable, waterproof, lightweight, easy to mould and recyclable- key properties for construction materials. So what if all of this plastics waste could be converted into building materials for low-income populations? Existing initiatives are promising, but not yet reproducible on an industrial scale. A number of building materials can be made of post –consumer plastics mixed with different waste stream materials. From agricultural waste such as sugarcane bagasse –a byproduct of the sugarcane industry and coffee dregs, to uncrate waste and construction debris, compounded with recycled plastics, there are many ways to obtain materials to produce bricks, roof tiles, and plastic lumber and other useful elements for building. Many construction companies are using plastic materials. The components used include everything from plastic screws and hinges to bigger plastic parts that are used in decoration, electric wiring, flooring, wall covering, water proofing and so on.
So perhaps plastics are not necessarily the problem. They can be part of a pathway towards a more sustainable way of living. Using a natural or renewable resource is not necessarily environmentally friendly. The ecological footprint of a polymeric material smaller than that of natural materials which have a sizeable demands on arable land, clean water, fertilizers and regeneration time. According to the Global footprint Network, before the pandemic Covid-19, we were demanding 1.75 times the available resources of the planet. Working with the “recyclable” waste and developing plastics alternatives to natural materials may reduce this demand and leave a cleaner and more sustainable planet for the next generations. Building materials made from recycled plastics are not yet widely used in the construction industry- prototypes have mainly been used for demonstrative installations. It will take political will and widespread environmental awareness to encourage more investment into the potential in plastic recycling. But hopefully the tide is beginning to turn as a consequence of the increasing pressure from public opinion about the plastic pollution matter. Thanks to the engagement of government and industry to the idea of a circular economy it seems that there will be an opening in the market-and in people’s mind-to welcome plastic initiative to replace conventional building materials.
(The views expressed is the writer's own - sjugeshwor7@gmail.com)
