After a long time, polyamide and nylon have both proven to be essential in fabrication industries due to their excellent qualities. Aside from their importance, they look similar too. And because they look so similar, many manufacturers, and even you, may mistake one for the other.
But, are both materials the same or different?
After reading this article, you’ll be able to understand and easily differentiate nylon from polyamide.
What Are Nylons?
Nylon is a synthetic fabric-like material that is made from crude oil. You make nylon chemically by combining several carbon-based molecules. As each of these molecules is heavy, they make nylon a material with high molecular weight.
Nylons are also really resistant to harsh chemicals, and they’re not easily spoiled with oils. It may help if you also knew that the different types of nylon have varying degrees of luster. While some may be highly lustrous, some are mid, and a few others may appear dull.
What Are Polyamides?
Polyamides, like its name, are made of many amides. They are materials made of carbon-based molecules or carbonyl groups bound to nitrogen atoms. Polyamide is formed and linked by amide links and hydrogen bonds. Both increase its tensile strength and ability to form crystals.
Polyamide can be naturally occurring or they can be synthetic. Silk and wool are common examples of naturally occurring polyamides. Synthetic polyamides are grouped into three classes:
- Aromatic Polyamides: This class of polyamides is also called aramids. They are known for their strength and high resistance to extreme temperature changes.
Aramids are used to create fabrics like Nomex, Kevlar, and other similar fibers. These fabrics are used to make fire-resistant and bulletproof clothing and vests.
- Aliphatic Polyamides: This is the class where nylons fall. They have only single carbon bonds and do not have double or triple bonds. They have low friction and creep too.
- Aliphatic-Aromatic Polyamide: These polyamides have the features of both aliphatic and aromatic groups. They are semi-crystalline, too. A good example of aliphatic-aromatic polyamide is polyphthalamides.
Polyamide is easily destroyed by acids and polar solvents. They are also excellent weight bearers, and they are easy to maneuver. Although maneuvering them is easy, they remain firm, and they can return to their shape and size even when subjected to extreme temperatures. Another great quality is that they are really resistant to stress.
Difference Between Polyamides and Nylons
Polyamides and nylons, as earlier discussed, are similar, but they have some key differences.
1. Nature Of Production
The first and most obvious difference is that while nylons are purely man-made, polyamides may be naturally occurring or man-made.
2. Chemical Structure
The chemical structure of nylons is more orderly and linear. They also usually have single bonds and are in a symmetrical fashion, which is different from the average polyamides.
Polyamides, on the other hand, can have different structures based on the monomers used. They may have an orderly arrangement, they may be haphazardly arranged. The arrangement depends on the type of polyamide.
3. Production Process
Nylons are mainly produced by polycondensation. However, for synthetic polyamides, you can manufacture them using different methods like polycondensation or ring-opening polymerization of the base substance.
4. Moisture Absorption
Both nylon and polyamide are slightly different in their absorption of moisture. Nylons are way more resistant to moisture. Polyamides are only fairly resistant as they can mix slightly with water.
5. Range Of Application
Of course, since nylons are a sub-branch of polyamides, you’ll expect polyamides to have a wider range of applications in different industries, and it’s so. Nylon has a smaller range of applications. But, you use nylons where you need more strength, resistance, and high-quality machined plastics.
The truth remains that nylons are a special kind of polyamide, and they have gained a level of success. In fact, they have gained enough popularity to stand out as a class of their own.
Identifying Nylon From Polyamide
Since we established that nylon and polyamide have some differences, then there should be ways that you can be able to differentiate one from the other.
Flame Test
To carry out the flame test, burn a tiny portion of the material, then observe the smell, nature, and color of the smoke.
When you burn nylon, you’ll see something like a bluish flame with a yellow tip, it smells like burnt hair, and it melts as it burns. Other polyamides form soot, and they smell of marigold as they burn. Other polyamides don’t melt as they burn.
How They Mix With Acetic Acid And Soda Ash
Another way to differentiate them is to mix them with acetic acid and soda ash (which is mildly alkaline by the way). Acetic acid causes nylon to precipitate, and the precipitate produces a soluble mixture. Mixing nylon and soda ash forms a soluble mixture too. Polyamide, on the other hand, is insoluble in acetic acid and soda ash.
Dissolution In Acids Or Alkaline Solutions
The third way to differentiate them is to know the kind of solutions they dissolve in. Nylon dissolves better and faster in highly concentrated alkaline solutions. Other polyamides are more likely to dissolve in highly concentrated acidic solutions.
Laboratory Identification
The surest way to differentiate them is to send a sample to a plastic identification lab. Here, they’ll carry out Fourier Transform Infrared Spectroscopy to know the exact type of polyamide.
What You Should Look Out For When Selecting Between Polyamides and Nylons
When choosing from these two options, there are a lot of things that you must consider. Considering the right things will positively influence your choice of one of these two.
Some important details to look out for include:
1. What Specific Qualities Are You Searching For?
Before you choose from one of these two, you must be conversant with the qualities one has over the other. You must also know the quality that you are the most concerned about.
When you have no specific quality in mind, then you must evaluate and compare the quality of both. Evaluate properties like strength, resistance to harsh chemicals, and extreme temperatures.
You should also assess qualities like the weight-bearing strength and design of the material. Doing this is very important when your production has to do with carrying weights at some point. When you check these qualities in both materials and subject them to scrutiny, you’ll know which of the two is best for your production process.
2. Do You Have Specific Applications In Mind?
Sometimes, your choice of either polyamide or nylon depends on what you want to produce. If you want to make bulletproof clothing, then you should opt for aramids. If you are manufacturing something that needs strength, nylons are a better option. For general stuff, general-based polyamides like nylon 6 are good options.
Different productions and applications may require specific kinds of qualities which may only be dominant in one of the two. The deal is to know what your production plant would be manufacturing. That way, you’ll choose the best materials for your production standard.
3. How Much Does It Cost? How Available Is It?
You’ll agree with me that most times, these two qualities go hand in hand. Oftentimes, your choice of one of these depends on your budget and how available the materials are.
Nylon is usually cheaper and easier to process. It has several applications. Most nylon grades are common too, so you may not spend so much to source them.
4. Are They Sustainable In The Nearest Future?
As you go on to make a choice, you need to always keep in mind that using polyamides and nylon to make certain consumables may change with time. And since the world of production constantly evolves, you must choose options that will still be trendy and important.
You should also choose materials that are flexible and easy to enhance. This way, you’ll win regardless of the trend.
Uses of Polyamides and Nylons
There are numerous uses for polyamides and nylons, and some of them are:
- In the textile industries, polyamide and nylon are used to make shirts, hoses, lingerie, socks, bedding curtains, carpets, and so on.
- In healthcare, some medical devices like surgical gowns and instruments are made out of polyamide. This is especially owned to their resistance to extreme heat, so they can stand sterilization and harsh chemicals. Also, nylons are used to make nylon sutures amongst others. You can use any of the two to make 1mL sterile syringes, gastric tubes, nasal cannulas, etc.
- In plastic industries, you can use polyamide to make helmets, pipes, and protective equipment.
- For automotive industries, polyamides are suitable for car parts like engine covers, gears, light trim, bushings, electrical connectors, and fuel lines.
- In electronics, both are suitable for phone parts, as insulation materials, connectors, computer motherboards, and so on.
- For kitchen wares like pots, spoons, tableware, saucepans, etc.
- For consumer products, both are used in 3D printing, braces, laundry bags, prostheses, shoes, zippers, etc.
Conclusion
Think of polyamide and nylon as a child and her grandparents. The child (nylon in this case) still carries a few morphological and physical qualities of the grandparent, although there are several alterations already.
Both materials are similar, but again, there are slight differences. So, before you choose either of these two, you must make sure that you know what you want. That way, you’ll make the best out of what you are producing.
