Synthetic materials are a big part of our closets, even if they might not be our first choice. Sure, natural materials feel much nicer on your body and they’re better for the environment, but they can’t really compete with the performance of a good man-made fiber. That’s why I want to tell you everything about acrylic and polyester, so you can know exactly what to expect from these synthetic materials!
Both have their pros and cons, and both are still widely used. I will focus on the use of acrylic and polyester fibers in clothing – the use of these materials outside of the clothing industry is so broad that it would take me way too much time to cover it all. In this post, I will tell you about all the properties of polyester and acrylic fibers, including their weather resistance, breathability and durability. I’ll also cover how they are used in clothing, so you can know exactly when you should look for these materials and when to avoid them!
Polyester is a synthetic man-made material that has a myriad of different functions and applications, but I will focus on its use in outdoor gear and jackets in particular in this post.
Polyester is hydrophobic, meaning that it has a really low tendency to absorb water. The fibers can actually let water pass through, which makes polyester an excellent moisture-wicking fabric. That’s exactly why it is often used in garments that need to be super breathable – it only takes a couple manipulations during the manufacturing process to give polyester excellent ventilation properties.
That’s why your favorite softshell hiking jacket is so lightweight and breathable, even though you didn’t think it would be. A common misconception is that synthetic materials are not breathable, but that’s simply not true. Keep in mind that polyester is man made, which means that it can be manipulated during production. It’s possible to treat the fibers during the manufacturing process so that you can enhance certain properties. You can make it super breathable or you can make it entirely water repellant. That’s exactly why you see different polyester garments out there with so many different features!
Additionally, polyester is often blended with natural fibers to create tougher and stronger fabrics. Spinning polyester with cotton results in a tough but breathable material that feel nice against the skin, while blending it with other synthetic fibers creates a material that’s resistant to nearly all elements.
Acrylic fibers are made from a polymer and they were first developed by DuPont back in 1941. It wasn’t until the 1950s that acrylic fibers started being mass produced and used in a wide variety of garments.
These synthetic fibers are strong and warm, and they are often used for making sweaters, tracksuits and warm and fuzzy linings in boots and gloves. That’s because acrylic has excellent heat-retention properties and it’s one of the warmest synthetic materials in existence.
However, the main reason acrylic has such excellent heat retention properties is its lack of breathability. The material has horrible ventilation, which makes it great for insulation and heat trapping. But if we’re talking about lightweight summer clothes, it’s best to stay as far away from acrylics as possible.
Additionally, acrylic fibers have really good moisture wicking properties. They are often spun together with natural wool, in order to increase the water resistance of the wool. And that’s why most acrylic products you see are garments for cold and wet weather – the properties of the material thrive in those conditions.
On top of that, acrylic is also spun into yarns that are very often used in crocheting and knitting. I’ve actually made a bunch of scarves with acrylic yarns, and I can’t even begin to tell you how ridiculously warm they all were! But I can also vouch for the horrible breathability of the material, especially when you have a garment with a really tight knit.
Another thing worth noting about acrylic is that it’s prone to pilling, so you might want to invest in a depiller if you have a lot of clothes that are made from acrylic fibers. This material is also extremely resistant to UV rays, which seriously impacts its recycling capabilities. But I’ll talk more about that later.
Synthetic insulation is most often made from polyester because it has such excellent insulating properties. And, although down is thought to be the warmer option, synthetic insulation has become extremely popular over the last few years. The main reason for that is its performance in wet weather.
Down clusters clump up when they get wet, which makes them unable to trap heat. That pretty much means that your fancy $400 down parka is absolutely useless if it gets soaking wet. But that’s not going to happen with a $50 polyester jacket – synthetic insulation can get wet and it will continue keeping you warm without any problems. That’s exactly why it is so popular in outdoor gear and especially jackets for wet weather.
On top of that, polyester insulation is excellent at providing warmth without any bulk. Down jackets are incredibly warm, but they are also thick and bulky. Jackets that have good polyester insulation can be incredibly packable, and Patagonia’s Nano Puff is a great example of that. In fact, that jacket even features Primaloft’s new and improved type of insulation, which is made with recycled polyester!
Polyester is a more versatile synthetic than acrylic and it’s found in many different shapes and forms. It is used in everything from waterproof bomber jackets to warm and cozy fleece jackets, which have widely different properties.
Hardshell jackets like bombers are more commonly warm as outer layers or shells. They are usually thin and lightweight, and they have excellent water resistance. These jackets can be worn alone for protection from the elements, or they can be combined with softshell jackets for full protection from the weather.
Polyester softshells like fleece jackets are usually worn as mid layers. They tend to be very warm and they are perfect for people who are looking for lightweight protection from the cold. Fleece is also one of the more breathable versions of polyester, which is why these jackets are so popular with hikers and alpinists.
And you also have jackets that use both forms of polyester. Fleece is often used as inner lining that provides the warmth, while the smooth form of polyester works perfectly as a rugged outer shell. The end result is a lightweight jacket that is warm, weather resistant and best case scenario, super stylish!
Acrylic is actually warmer than polyester so it must be even better for insulation, right? Well, not exactly. A good winter jacket is not only very warm, but also breathable. It’s supposed to keep you comfortable, and that means that if you start sweating, the jacket should be breathable enough to let that moisture escape.
That doesn’t happen with acrylic, and that’s why synthetic insulation isn’t made with it very often. But that doesn’t mean you don’t see acrylic in jackets – it’s often used to create faux fur trims on hoods and fuzzy or faux fur lining on parkas.
Now, the advantage of acrylic lining is that it will keep you warm no matter how ridiculously cold it gets outside. But the compromise you are making is that you’re going to sweat, so ultimately it’s up to you to decide what you prefer.
Acrylic is also used to make fuzzy lining in boots, but I would recommend against buying these. While they might be really warm and cozy, lack of breathability is a serious issue when it comes to footwear. Especially since acrylic has a tendency to absorb odors, and that basically means that if your feet get sweaty and start smelling nasty, it will take quite a lot of tries to get that scent out of your boots.
Additionally, most faux fur coats that you see out in the wild are made with a high percentage of acrylic fibers. They are easily manipulated to look similar to natural fur, especially when they’re mixed with a bit of polyester and modacrylic. Acrylic coats and jackets are usually exceptionally warm, even if they don’t have any proper insulation.
Even though acrylic is used in certain parts of some jackets, there’s no such thing as a jacket that’s fully made from acrylic fibers. The lack of breathability is just too big a downside – if you start overheating just because of a thin layer of acrylic lining, imagine how hot you would get if the entire thing was made from acrylic. Even faux fur coats with an exterior made from acrylic will often include a polyester lining, just for the sake of breathability.
But this wool-like fabric does have a bunch of other uses. It is commonly used in sweaters as a more affordable cashmere alternative. And honestly, if you want cheap warmth, an acrylic sweater is the way to go. Just remember to wear something soft and breathable underneath it, since acrylic isn’t exactly known for premium next-to-skin comfort.
Polyester is much more often used in outdoor great than acrylic, because it is the more breathable fabric. Hiking, climbing and similar outdoor activities are all physically demanding, meaning that you start sweating not long after you’ve started doing them. An acrylic garment just won’t be comfortable in that situation since it can’t let that sweat evaporate.
Polyester, on the other hand, is extremely popular for outdoor gear because it can have outstanding breathability. But bear in mind that you have to specifically look for breathable polyester. The fibers can be manipulated so that they’re not to breathable, which is why some polyester garments are more comfortable than other. But, as long as you know exactly what to look for and you do your research when shopping for outdoor gear, you should easily avoid any nasty surprises.
Also, acrylic is used in outdoor gear to a degree, it’s just not the main material. You will have it in the lining of your boots, in your favorite warm gloves, and even tracksuits, if that’s your preferred choice of hiking uniform. It might not be as water resistant or as breathable as polyester, but whenever there’s a need to make a garment a bit more warm, acrylic fibers are usually the go-to choice of manufacturers.
Polyester is easy to recycle and quite a lot of brands that make outdoor gear are using recycled polyester to make their gear. Patagonia is one of the brands that actually gets plastic waste from landfills and transforms it into fabulous high end jackets that we love wearing.
Acrylic, on the other hand, is much tougher to recycle. It’s considered a group 7 plastic, so it’s usually not even collected for recycling. It can be exposed to the elements for years without any signs of decomposing, or even losing its transparency. Acrylic also has excellent chemical resistance, which is exactly why it is so hard to recycle. If you’re trying to be more environmentally friendly, polyester is definitely the better option.
Then again, the toughness and elemental resistance of acrylic means that you will be able to wear the item longer. Especially if it’s acrylic in the form of faux fur – the fibers are usually mixed with polyester to achieve that fuzzy look and feel, and they can handle years upon years of wear and tear. If it’s pure acrylic like in sweaters, the only issue you’ll have to worry about is pilling. But even that can easily be solved with a cheap depiller machine, or even just an old razor.
Synthetics like acrylic and polyester are both essentially plastic. And when you expose plastic to high heat, it melts. That’s why it is very important that you don’t expose clothing made from these materials to high heats, which means you can’t put them in the dryer.
The same goes for items that are made from natural materials but have some synthetic fibers in them. If you wash those with boiling hot water or put them in the dryer, you will almost always melt the synthetic fibers in them. And in most cases, those fibers were added to make the clothes stretchy – when the synthetics melt, the garments lose all their stretchiness and become very loose instead.
Cold or lukewarm water and air drying are your best friends when it comes to washing items that are made from either polyester or acrylic fibers.
Anna is the co-owner of expert world travel and can't wait to share her travel experience with the world. With over 54 countries under her belt she has a lot to write about! Including those insane encounters with black bears in Canada.