In short, polythene is used for almost everything. And that’s no exaggeration. Polythene packaging is just the tip of the iceberg, because this material has found use in every single industry, product and process you can think of.
That’s because polythene has some unique, amazing properties.
It’s waterproof. It’s strong. It’s super light. As a film, it’s soft and malleable, with stretch and give – this makes it resistant to tearing and good for protective applications. In higher densities and thicknesses, it behaves like other solids, and can be made into virtually any shape.
It is a fantastic thermal and electrical insulator, with a melting point of between 110ºC (LDPE) and 130ºC (HDPE and UHMW polythene). Its properties can be changed by blending additives in – making it unbelievably versatile. It’s a miracle material, and it has changed the course of history many times over.
Read more – The Physical Properties of Polythene
In this post, we explore the question “what is polythene used for?” – and try to list every use for polythene we can possibly think of. Can you think of any more? Drop us a line and we’ll add it to the list!
What is polythene used for?
Let’s get the easy one out of the way first: packaging. This is the primary use of polythene around the world.
Bottles, bags, films and sheets… Polythene makes them all possible. Milk comes in HDPE bottles, and most foods are sealed or packaged in LDPE – it’s everywhere you look, both at home and at the shops. Even if you can’t see it, or if you actively reduce your personal use of it, polythene has almost certainly been used somewhere in the logistics process, in the form of…
Polythene sheets, shrink wrap and pallet covers are used to keep loads safe from moisture, dust and dirt – both in transit and in storage. Wraps are used for protection, and to keep the load stable on a pallet. Covers and sheets can be reused, or recycled. Even polythene shrink wrap is recyclable.
Polythene packaging is great and all, and it certainly has made our lives more convenient – but thanks to the amazing properties of polythene, it can do so much more.
What is polythene used for besides packaging?
Here’s where polythene’s uses get interesting…
In the future, polythene might become one of the most important materials in establishing a working colony on Mars. It could also save wild salmon from becoming endangered or extinct.
Today, it’s a life-saving material in medical and military applications, a vital component in construction, essential to agriculture and crop farming, and of course – the best way to package just about any product in the world.
Here are just some of the uses for polythene that you might not know about.
PPE – and bulletproof vests
Aprons, gowns and tabards, as well as gloves, are primarily made of polythene. We all know how important PPE is, and how much we relied on it throughout the worst of the Covid-19 pandemic. Polythene helped to protect NHS workers, care workers and the people on the frontline the whole time – and continues to do so.
Read more: Medical-Grade Polythene
Believe it or not, bulletproof vests are also made with ultrahigh molecular weight polythene (UHMW). It has a tensile strength many times greater than that of steel when woven into threads, but it’s incredibly light and flexible by comparison.
In construction, polythene sheeting is used as an under-slab damp-proofing membrane, but it also has uses beyond this. Broken windows, shifted roof tiles and broken cladding can all be secured and temporarily weather-proofed with polythene sheeting, while waiting for a permanent solution. It’s also great as a covering for anything you want to keep dry or dust-free outdoors or indoors – like when painting or doing some DIY.
Surprisingly, concrete is cured using polythene, too. It helps control temperature and moisture, for a crack-free finish and enhanced structural properties.
Farming and food
Polythene for farming is widespread around the world. It helps fight weed growth, increase fertiliser uptake, regulate temperature and humidity, and protect plants and soil from bad weather. It’s also used for grow bags and irrigation systems, and has been credited with improving crop yields by up to a third. The food industry as a whole is highly reliant on polythene, and we’d struggle to feed everyone in the world without it.
The Salmon Cannon
Remember the fish tube memes, from back in 2019? Well, we’re pretty sure that tube is some kind of polythene blend. The makers of the Salmon Cannon, Whooshh Innovations, claim a proprietary plastic mix is used that has a super-slippery lining for the fish to move down. But, with that much flexibility and strength, we’d be willing to bet it’s a polythene base with a high slip polythene additive.
While we’re talking about fish – here’s another fishy use for polythene!
Koi fish transport bags
In our post, How to Transport Koi Fish, we cover our experience working with the Koi Carp Company to create a custom box and bag solution for transporting koi. These gorgeous fish are highly sensitive (not to mention expensive), and need absolute protection in delivery, as well as during transit to and from shows.
Containing and managing hazardous waste
Extremely dangerous materials – like biological, chemical, medical, and poisonous waste – can only be contained with a material as strong and flexible as polythene. Hazardous waste bags and asbestos removal bags are just a couple of examples where polythene is used to save lives.
Toys, play equipment, benches and outdoor furniture
Outdoor toys and play equipment are routinely made with recycled polythene at the end of its useful life as a packaging solution. It retains its strength and weatherproof properties, and provides communities with safe, fun play areas for years and years. It’s also common to find plastic benches made using recycled polythene, for the same reason.
Cables, tubes and piping
Polythene is an excellent electrical insulator, and its high ductility covers wiring easily. It’s flexible and tough, making complex routings possible. During WWII, polythene was used to make insulation for the cabling of radar equipment because of its low-loss properties at very high frequency radio waves.
Polythene can also be extruded into pipes, hoses and tubes for plumbing applications. Because it’s food safe, it can deliver water and other liquids for consumption – or be employed in irrigation systems, drainage fields and wastewater management. Oil and gas pipelines regularly use MDPE for delivery, as it’s flexible enough to resist cracking and bursting, even in high pressure and extreme torsional stress environments.
Read more: Civil Engineering Projects using Polythene
Car parts made of polythene
One of the most important uses for polythene in automotive manufacturing is fuel tanks. A special grade of HDPE is used in fuel tank manufacturing, with an added copolymer that prevents chemical breakdown of the polythene in the presence of fuels. MDPE contributes to fluid hoses and cable insulation in cars – and LDPE is used for lightweight impact absorbing parts (like bumpers), as well as packaging auto parts, of course.
The crew aboard the ISS relies on polythene for their food – and NASA is actively investigating polythene as a building material for spacecraft. One day, humans might be making polythene out of thin air on another planet, by synthesising polythene on the surface of Mars to be used in 3D printers…
3D printing on Mars
This one’s quite amazing. Polythene is actually far from ideal as a 3D printing material on Earth: it doesn’t stick to many base materials apart from itself, and can be messy and fiddly to work with. There are far better alternatives.
But it does work – particularly ultrahigh molecular weight polythene. This is important, because one day, humans might be forced to leave the planet for somewhere like Mars. And on Mars, there’s probably no oil to make traditional plastics from.
But polythene can be made using the elements available on Mars: it has a carbon dioxide-rich atmosphere and water (locked up in ice).
With lots of electricity, water can be decomposed into hydrogen and oxygen. The carbon dioxide in the atmosphere can be combined with the hydrogen, to make carbon monoxide and water.
Carbon monoxide, hydrogen and a catalyst will produce ethylene and water. Ethylene and a catalyst produces polythene.
And just like that, future colonists on Mars will have an abundant supply of material to build with, and 3D print the tools they need (and other objects we take for granted here and now).
Pretty cool for the stuff we all chuck in the recycling bin without a second thought!
One material, countless uses
Off the tops of our heads – that’s every weird and wonderful application of polythene we can possibly think of.
So, next time you’re sitting on a park bench, visiting the supermarket – or have to put on a bulletproof vest and fly to Mars (who knows?!) – think of the magic material that made it all possible: good old polythene!
What do you want to know about polythene?
Ask our friendly team of experts at NPF Packaging – and start your order for polythene film, layflat tubing and polythene bags. We’ll deliver polythene packaging products to your exact specifications, with custom tints, prints and branding available. Get a quote now, or call us on 01773 820415.