Friday, June 14, 2013

Fiber Feature - Synthetics


When most experienced knitters hear the word "synthetic", the first thought is harsh, squeaky, cheap yarn. The very thought of synthetic yarn often elicits a crinkled up nose, a cringe and possibly a shudder!

Not so fast!!!

Yes, many of us are a bit snobbish about synthetic, but really we shouldn't be: they do have their appropriate uses and there are some really pretty and very soft choices!

There are four main categories of synthetic yarns: nylon, acrylic, spandex, and polyester.  I have learned quite a bit in just researching for this blog post.  As I mentioned last time I love science stuff and synthetics are incredibly diverse and made from many different chemicals.  I've learned that all synthetic and man-made yarns are made of polymers.

What is a polymer, you ask?

Let us again return to high school science! Remember that molecules are groups of atoms that have unique properties. For instance, a water molecule is two hydrogen and one oxygen atoms. You may also remember that there are different kinds of bonds that molecules can form and one type is a chemical bond. Molecules that can form chemical bonds are called monomers.  Long chains of monomers chemically bonded together are polymers.  Polymers are both naturally occurring and are synthesized.  An example of a naturally occurring polymer is protein which is made from long chains of amino acids.  Since around the late 1800's scientists have learned that by imitating naturally occurring polymers with man-made molecules they can create useful substances.  Thus rayons and synthetic fibers were born.

Synthetic fibers can be made to imitate the drape, function, and feel of many natural fibers.

Here is a brief overview for each of the four main types of synthetics:

Nylon became popular during WWII to replace the silk that was no longer available for parachutes because of Japan's involvement in the war.  Before that it had been first used in toothbrushes and women's stockings. It is most often but not always made from petrochemicals.  It can also be called polymid, polyamide or polyamid.  Nylon is exceptionally strong, elastic, resists abrasion (which is why it's included in sock yarns), has a nice sheen, is resilient and doesn't absorb a lot of moisture.  Of all the synthetics, I think it pills the least.

Polyester is very similar to nylon.  It is lightweight and very strong, very durable so it is resistant to most chemicals, stretching, shrinking, wrinkling, mildew and abrasion. It doesn't absorb water so it drys quickly which makes it great for outdoor and exercise clothing.

Acrylic, of all the synthetic fibers most resembles wool in loft, elasticity, texture and hand.  It is light weight and easy to wash, is moth proof and resistant to damage from the sun or chemicals.

Spandex, also known by the brand name Lycra, is much like nylon or polyester but has tremendous elasticity.  It's able to expand up to 600% and spring back, maintaining its original shape for a long time.  It is often blended with non-elastic fibers like cotton to help garments, like jeans, maintain their shape and fit.

There are many different variations on how each of these main types of synthetic are made, what chemicals, spinning and dying process are used and each with its own unique name.

The main thing all synthetics have in common are low cost, strength, resistance to abrasion, ease of care, little need for ironing, low affinity for moisture which causes a tendency to conduct static electricity and attract microscopic dirt, and they all will melt or pull away from heat. They can be dyed in many vibrant colors.  Most acrylics and polyesters tend to be non-allergenic or at the very least non-irritating.

A quick word about microfibers.  These are are synthetic fibers that are made very, very thin - about 1/20th the diameter of silk!  This gives fabric made from them incredible softness, the ability to wick moisture away from skin and dry quickly making it perfect for work out clothing.  It also is used for cleaning cloths because it takes advantage of synthetics' natural affinity for dust and dirt.  Some kinds of microfibers are also split (much like a cucumber or a radish that has been scored down its length) which allows the microfibers to soak up liquids and hold onto them.

We stock many different synthetic blend yarns and some 100% synthetics as well.  Some of our most popular are Universal Classic Shades line, the Plymouth Encore line including Coffee Beenz & Jelli Beenz, the Berroco Vintage line, Berroco Comfort line, Cascade Pacific & Cherub lines and the Red Heart Boutique lines.  Most of these are great for knitting easy care, machine wash, gentle tumble dry garments.

Check out our searches for all the yarns that contain acrylic, nylon, polymide, and polyester.  You'll see that most of our fun novelty yarns contain synthetic fibers because they can be made to do pretty much what we want them to do.

Here, feel this....that's really soft and yummy and the color is so pretty, what is it?  It's acrylic!

As always, I hope this is useful information.  If you found this helpful or I've left something out, please let me know.  askTerry (at) jimmybeanswool (dot) com.



  1. ...... a water molecule is one hydrogen and two oxygen atoms. ....
    >>> Water is made up of 2 Hydrogen & 1 Oxygen atoms. H2O not HO2!!!

  2. Rudio, thank you so much for the correction. I do know that and somehow I typed it out incorrectly. I'm so glad you spotted it!