Plastics made from plants could be the answer to the world’s waste problem

Oh, well, that is depressing. Image: Getty.

Plastics are incredibly useful materials with extremely diverse properties, allowing a multitude of different applications that benefit our lives.

Bottles and forks aside, in the medical field alone plastics have been used for artificial heart valves, medical implants and devices, controlled drug release, specialist surfaces and coatings that repel water, organic batteries – the list is endless.

But, with marine plastic debris estimated to reach 250m tonnes by 2025, governments across the globe are starting to think about how to overcome this significant problem.

A fundamental part of this issue is that non-sustainable, single-use plastics account for up to 40 per cent of global plastic production. This equates to around 128m tonnes. The vast majority of these plastics have low recycling rates and do not biodegrade in an acceptable time span – polypropylene can take millennia to break down properly.

Worse still, if these plastics find their way into the marine environment, the motion of the sea along with sunlight can cause the plastics to fracture into small particulates called “microplastics”.

The presence of macro and microplastics in our oceans has been shown to have a detrimental effect on marine life. But the potential effect on human health is much less well understood.

A ban on the production of cosmetics and personal care products containing plastic microbeads came into effect at the beginning of the year. Realistically, though, this only accounts for an estimated 680 tonnes of microplastics per year in the UK.

The problem with plastics

It is clear then that plastic waste is a complicated problem – spanning economics, sustainability, social pressures and recycling infrastructure in both developed and developing countries. But while it’s widely known that plastics can be an issue for the environment, what isn’t often known is that the persistence of plastics in the environment is actually closely linked to how they are made.

The overwhelming majority of plastics are made using oil-based materials, meaning that, by their chemical nature, many plastics have no oxygen content. This makes them very hydrophobic (water hating) and, as such, it is very difficult for common bacteria or enzymes to break them down if they enter the environment.

Over the past few decades, there has been increased awareness of our dependence on a limited oil supply and this has driven research into alternative, sustainable sources of chemicals. In particular, the concept of using bio-based materials as a resource rather than oil-based materials has really gained momentum. Sustainable bio-based material can be waste crops, waste wood, waste food – in fact, any waste biological matter.

Most importantly, these natural, bio-based materials can easily be broken down into smaller chemical building blocks – called “platform molecules” – which in turn, can be used to make other useful chemicals, including plastics.


Nature’s building blocks

Using these platform molecules, the Green Chemistry Centre of Excellence at the University of York, has been working with the plastics industry to create a new generation of bio-based polyesters. These are often used to make fibres for clothing, as well as films and containers for liquids and foods. The resulting materials are entirely plant based, recyclable and – importantly – fully biodegradable.

Aside from sustainability, the huge benefit of using biomass as a resource is the high quantity of oxygen that is incorporated into nature’s chemical structures (celluose, glucose etc). By using bio-based materials to make bio-based plastics, the oxygen content is kept in the material. The hope is that by having a high oxygen content, the bio-based plastics will have high, but controlled biodegradability. This means that the bio-based plastic can totally and safely break down into benign starting materials.

But although this new generation of sustainable plastics is a huge step forward, and a compostable plastic is of huge benefit, this is by no means the end goal for all bio-based plastics.

Circular economy

The circular economy is all about keeping resources in a constant loop, reusing and recycling them as many times as possible. This helps to minimise waste and reduce the need for brand new resources.

Treating plastic waste as a resource rather than a problem is an important change than needs to happen over the coming decades. This will help to preserve our remaining chemical materials, as well as protect our environment.

Enough plastic is thrown away each year to circle the earth four times. Image: Pexels.

Plastics are a fundamental part of modern society and they are here to stay. Ultimately, society has to move away from oil-based products towards sustainable bio-based alternatives. But regardless of whether a plastic is oil-based or plant-based, the biggest impact you can have on the life cycle of a plastic product is to reuse and recycle it.

As a consumer, this means you have a choice and the power to make a positive impact. Find out where your nearest plastic waste recycling point is and look to promote home collection and the proper recycling of all types of plastic waste.

The ConversationSo next time you use the last of the ketchup, help to preserve our resources by making sure your plastic waste stays in the recycling loop.

James William Comerford, Postdoctoral Research Associate, University of York.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

The media scumbag’s route of choice: A personal history of London’s C2 bus

A C2 bus at Parliament Hill. Image: David Howard/Wikimedia Commons.

London’s C2 bus route, which runs from Parliament Hill, by Hampstead Heath, down to Conduit Street, just off Regent Street, is one of the bus routes recently earmarked for the chop. It has oft been noted that, of all the routes recently pencilled in for cancellation after a consultation late last year, it was the one most likely to survive, for the simple reason that it links liberal suburban north London with BBC Broadcasting House and Soho; it’s thus the route most likely to be used by people who can convince someone to let them report on its imminent demise.

So it would come as no surprise that former Guardian editor Alan Rusbridger took to the Camden New Journal when the consultation began, arguing that it would be a disservice to the local community to discontinue a route where you can always get a seat – seemingly missing the point that the fact you can always get a seat is not a great sign of the route’s usefulness.

It wasn’t always that way. When I left university in 2000, and moved from accommodation near college to up to a rented shared house in N6, the C2 was my bus. I commuted to Soho for sixteen years: for more than a decade from flats around the Swain’s Lane roundabout, and for five years from Kentish Town. While my place of work bounced around from Golden Square to Lexington Street to Great Marlborough, it was always the most convenient way to get to, and from, work; especially given the difference between bus and tube prices.

So when it comes to the C2 I’ve seen it, I’ve done it, and bought the bus pass. And by bus pass, I mean those little paper ones that still existed at the beginning of this century. Not just before contactless, but before Oyster cards.

More importantly, it was before London buses operated a single zone. There was an outer zone, and an inner zone, with different prices. To travel from one zone to another cost £1.30, meaning an all cash commute was £2.60, whereas a paper bus pass was £2.00. That made it worth your while to divert to an early opening newsagents on your way to the bus stop (GK, in my case), even if you only got two buses a day.

It’s a measure of how greatly London’s buses have improved over the last twenty years, since first brought under control of the mayoralty, that pretty much everything about this anecdotage, including the prices, seems faintly mad. But there’s more: back when I started getting that bus down to Stop N, literally at the very end of the route, the C2 used single decker buses with a single door. It’s an appalling design for use in a crowded city, which meant most of any journey was, for most passengers, spent fighting your way up and down the middle of the bus to find a seat, and then back again to get off; or – and this was more likely – fighting your way up the bus to get into standing space the driver insisted was there, before fighting your way, etc.

Such buses – and in my former life in the English Midlands I went to school on one of these buses every day – are perfectly functional where bus stops are infrequent and buses rarely standing room only. But running through Camden Town at rush hour, they’re wholly unfit for purpose.

A Citypacer. Image: RXUYDC/Wikimedia Commons.

It could have been worse. I didn’t know this at the time, but a few years before the C2 route had been run using Optare City Pacers. Those are, let us be frank, not really buses at all, but minibuses. That’s something the reveals the C2’s origins, as a hopper route to the west end largely intended for the daytime use of Gospel Oak’s pensioners in the years immediately before bus privatisation. (The C11 has a similar origin, taking the same constituency from Archway to England’s Lane.)

Once responsibility for London Buses was moved to the newly established mayoralty, things improved dramatically. Under Ken Livingstone it went double decker in 2005, and 24 hour in 2007. Under Boris Johnson it was extended from its once, and future, terminus of Conduit Street to Victoria Station, swallowing up the cancelled sections of the 8 bus; this extension was quietly disposed of a few years later, once it was clear no one would notice. (I did.)


In those years I must have taken a C2 the best part of ten thousand times; but for all the years when I wouldn’t have been able to live without the C2, times have reduced its utility, and not just for me. I’m now a 214 sort of guy: these days the top chunk of the C2 route is duplicated exactly by that other bus, which starts up in Highgate Village and, once it gets to Swain’s Lane, follows the same path until the fork of Kentish Town Road and Royal College Street, opposite the long defunct South Kentish Town tube station.

From a few hundred metres below that point, at Camden Gardens, stop C, the 88 starts. That duplicates the rest of the C2’s route, with the exception of the run down Albany Street and onto Great Portland, for much of which the C2 is the only bus.

So the C2, old friend that it is, is pretty redundant in the age of the hopper fare, which allows you to change buses without paying a second fare. That’s even more true now the C2’s otherwise un-serviced stops are being giving over to a re-routed 88, which will pick up the C2’s most northern leg, by not finishing at Camden Gardens anymore and instead going all the way to Parliament Hill Fields. Which will be nice for it.

All this, however, ignores the best reason for getting rid of the C2 (or rather for merging it with the 88, which is what’s actually happening): that first character. The letter. Who wants a bus route with a letter in front of it when even half the night buses don’t have the N anymore? It’s relic of the route’s aforementioned origins as a ‘Camdenhopper’.

That C is twenty five years past its own utility. It’s just untidy. City Metric hates that sort of thing. Get rid.