May 28, 2024

I, Science

The science magazine of Imperial College

After Thomas Thwaites' Toaster Project, Annalise Murray tries to make a bioplastic yo-yo.

Look, it’s like this: I got cocky.

A few months ago, I tried the Big Apple Experiment. The Experiment is the brainchild of self-help guru Nikki Owens and purports to prove that our thoughts, words, and intentions can affect plants’ rate of decomposition. I popped two strawberries (don’t really like apples) into some Tupperware, I was nice to one and mean to the other, and, indeed, the ‘bad strawberry’ decomposed more quickly.

So, yeah, I got cocky. You would too if your vibes had somehow caused a plant to rot. I’d had one successful foray into citizen science, and I was on the lookout for another.

I’m pleased to report that inspiration struck whilst I was in an actual museum – specifically, the Design 1900-Now gallery at the Victoria and Albert Museum. Design 1900-Now is home to various interesting objects from the last couple of centuries, including the very first iPhone, a sofa designed by Salvador Dalí, and a really gnarly looking toaster.

Said toaster was made by Thomas Thwaites for his final project whilst he was a student in design engineering at the Royal College of Art. And when I say made, I mean made – he mined the mica and copper, remoulded recycled plastic for the casing, and smelted iron in a microwave. He called it The Toaster Project. It took the better part of a year, and it cost £1187.54. This was in 2011, so that’s roughly one billion pounds today.

My interest, obviously, was piqued. I had neither a year nor a billion pounds to devote to a similar project, but I did have a couple of hours, preferably not more than £5, and a considerable quantity of audacity. It was a go.

The first task was to determine what I was going to try to make. Thankfully, I recognised that I needed to set my sights somewhat lower than Thwaites’ toaster. The object in question needed to be small – preferably just one component – and made from something I could synthesise at home. I pondered this for several weeks, and for some godforsaken reason, the only thing I could think of was a yo-yo.

At its very simplest, a yo-yo consists of two evenly-sized discs, connected by an axle that acts as a spool for a length of string. The discs could be made from anything, but in modern yo-yos they’re generally made from plastic. In industry, plastic is made by mining crude oil or natural gas, which are then refined, cracked, polymerised, and manipulated into shape. Fortunately, however, fossil fuels aren’t the only source of polymers. Plastics can also be made from vegetable fats and oils, sawdust, straw, woodchips – or, as I eventually decided, starch. Sources of starch are cheap, abundant, and renewable, and tutorials detailing how to turn them into bioplastics are plentiful. 

My bioplastic required white vinegar, distilled water, glycerol, and cornstarch (that’s cornflour to those of us of a British persuasion). I was to combine the ingredients and heat, stirring continuously, until they came to a gentle boil. In order to make the plastic keep a certain shape, I needed to pour the mixture into a mould. I made my moulds by hacking the top off a mini-sized can of Diet Coke, which was both effective and probably quite dangerous.

At this point, I was still feeling pretty good. Mix, stir, pour – how difficult could it be?

As it turned out, very. My first batch prematurely plasticised itself and stuck to the pan. I added more water to the second batch, which resulted in a promisingly gelatinous consistency. I poured the second batch out, pried the first batch off the bottom of the pan, left them both on the kitchen bench for a few days to set, and that went about as well as you might expect.

The first batch (right) somehow managed to both not really set and dry out so much that it cracked. The second batch (left) evaporated. The small outcrop was supposed to be the axle. Not pictured: distinctly vinegary miasma.

My yo-yo took upwards of an hour, cost approximately £7, and it didn’t even yo. If I was aiming for maximum yo for minimum effort, I could’ve bought the “Flashing Yoyo Toy Outdoor Plastic Colorful LED Light Pulling Wire Flying Saucer Kids Classic Yo-yo Ball Toy”s from AliExpress, which would not only have yo-ed, but also spun around, lit up, saved my kitchen from certain destruction, and only cost six pence. I could’ve had 116 FYTOPCLLPWFSKCYBTs for the cost of one no-yo. They’re currently 5,000-ish miles away in a warehouse in China, but that’s not a problem; AliExpress only charge £1.85 for shipping. By all accounts, it’s a bargain.

Except that the price isn’t the only cost. A quick back-of-an-envelope calculation tells me that the FYTOPCLLPWFSKCYBTs’ journey to London would emit about half a tonne of carbon. If I wanted to pay to offset that, it would cost about £9, but, of course, I’m under no obligation to do so, and nor is anybody else. When I inevitably threw the FYTOPCLLPWFSKCYBTs away, they would either go to a landfill, where they would remain for the next five hundred years, slowly leaching methane into the atmosphere, or they would be incinerated. All that before we even begin to consider actually manufacturing the thing.

Ironically enough, the no-yo is pretty carbon intensive itself. I ran our gas hob for the better part of half an hour, I destroyed four aluminium cans that could’ve been recycled, and I had to have a few fortifying snacks. If there is one takeaway from this experiment, it’s that trying to manufacture your own yo-yo is probably not a good idea – but maybe buying one for a pittance from halfway across the world isn’t a good idea either.

Maybe the takeaway is this: making things is difficult and expensive. It is difficult to make a yo-yo, and it is very difficult to make a toaster, and perhaps, then, we might conclude that it’s more difficult to make most things than we’ve been led to believe. When we’re sold cheap and easy, somebody still pays.    

Image credit: Annalise Murray.