Polyamide Vs Nylon, What is The Difference?
Polyamide fiber and nylon materials are increasingly used in many industries due to their exceptional properties, toughness, and versatility. Understanding the differences between these materials is important to help you make informed decisions when selecting the right material for your products. In this article, we’ll define nylon plastic and polyamide fabric, compare them, discuss their different uses, and more.
Let’s start by answering this question: What is polyamide?
What Are Polyamide Fabrics?
Simply put, polyamide is a family of naturally occurring or synthetic materials that are known for their durability, strength, and stretchable structure. This makes it an excellent material for various applications that require these characteristics. DuPont developed and patented this material in the mid-1930s as an alternative material to women’s silk stockings.
The word “amides” in “polyamides” refers to the organic compounds that consist of carbon and oxygen bonded to a nitrogen atom through a much stronger double bond. When these compounds chemically react together, they create long chain links that form a flexible and strong material.
Many industries extensively use polyamides due to their remarkable characteristics. Synthetic polyamides find applications in the aerospace, automotive, consumer goods, construction, electronics, medical, packaging, sportswear, and textile industries. But the biggest consumer of polyamides is the transportation industry, which makes up 35% of polyamide usage.
What Are Polyamide Fibers Used For?
It’s not only their durability and flexibility that make polyamides useful for various applications. Their ability to absorb moisture, resist certain chemicals, and remain stable under the influence of heat is also impressive. Because of these special properties, polyamide material is suitable for a wide range of industries and purposes. Let’s go over some of them.
1. Automotive Industry
The automotive industry is one of the leading consumers of polyamide material, largely due to the increased use of this compound in the production of lightweight vehicles. It’s often used in the production of airbag containers, air intake manifolds, car upholstery, engine covers, fan blades, fuel and cooling systems, seat belts, tires, and other external parts (e.g., fuel caps, grilles, and wheel covers).
2. Industrial Cable Protection Systems
In terms of global use, cable protection systems made with polyamide material are extensively used in the train and transit industries. It’s the preferred material for conduits (protective tubes that hold the cables) and fittings (keep conduits in place) because it’s lighter than PVC-coated metal conduits. These components need to be lightweight to save fuel, reduce labor time, and ensure safety.
3. Food Packaging and Beverage
Polyamide is used in the food and beverage industry more than you think. Manufacturers have polyamide systems in place to maintain high standards of cleanliness, especially in areas where components might encounter food.
Here are some specific examples of the applications of polyamide in the food and beverage industries:
Packaging
Packaging materials, such as films and containers, use polyamides because of their exceptional high-barrier properties. This allows them to protect food from environmental factors (air, light, moisture, and water), so it stays fresh, retains its flavor better, and lasts longer.
Food Processing Equipment
Some of the food processing equipment that’s made from polyamide-based materials are conveyor belts and seals. They’re perfect for this purpose because they’re usually non-reactive, resistant to wear, and have low friction.
Food Contact Materials
If you look around your kitchen, you might find utensils, food storage containers, and kitchenware that contain polyamide materials. Polyamide-based kitchen tools usually meet safety standards and are durable.
4. Chemical and Manufacturing
Polyamide also makes a cost-effective addition to a variety of fibers, plastics, and resins. Polyamide epoxies, for instance, are usually one of the main ingredients in primers. They enhance adhesion, inhibit corrosion, improve surface wettability, and ensure the primer accommodates surface expansion or movement.
Other common uses of polyamide material in the chemical and manufacturing industries include:
Ballpoint pen ink.
Epoxy floorings.
Epoxy paints.
Heat-sealing adhesives.
Ink Binders.
Lacquers.
Printing ink.
Seal coatings.
Varnishes.
5. Robotics
In creating robots, manufacturers require parts that are extremely flexible and tough. Specially engineered polyamides provide practical and effective solutions to meet this requirement. Their remarkable ability to resist abrasion, cracking, warping, and failure from repeated stress makes them a popular choice for making various robot parts, such as bearings, cables, gears, and wires.
In addition, polyamides are lightweight and malleable. This makes them highly suitable for producing robotic parts with intricate shapes, such as end-effectors and grippers.
6. Textile Products
Is polyamide breathable? Natural polyamides, such as silk and wool, are breathable. Synthetic varieties are not, but they’re more elastic.
Whether they’re breathable or not, there’s no denying that polyamides have many favorable qualities that make them good clothing materials. Polyamide fabric is often used in swimwear and active wear because of its elastic and moisture-wicking qualities. Polyamide fabrics are even used in making more specialized items, such as airbags and seat belts.
What Is Nylon?
In the 1930s, American chemist Wallace H. Carothers led a research team at E.I. du Pont de Nemours & Company—commonly shortened to DuPont—to develop the nylon material. It was first used as an alternative material for making recycled parachutes during World War II.
After the war, there weren’t enough traditional dress materials, such as cotton and silk, available. So, some people repurposed these nylon parachutes to make dresses. Many people liked the idea of using nylon for making women’s clothing, so the production of nylon stockings and lingerie took off.
So, what is nylon?
Nylon is specifically derived from crude oil. So, it’s a completely synthetic material—a polymer, to be exact. A polymer consists of chains of carbon-based molecules called monomers, which are like LEGO pieces that can join together to create long chains that make up the structure of a nylon material.
Nylon has a high molecular weight, which means it consists of long and heavy molecules. This is important because it means the material is durable and doesn’t break easily under pressure, like when you stretch it.
These days, manufacturers combine nylon with other fabric materials to achieve specific performance characteristics (e.g., flexibility and moisture-wicking properties). Some of the fabrics mixed with nylon are cotton, polyester, and spandex.
Nylon is usually used in manufacturing the following:
Airbags.
Carpets.
Clothing (e.g., lingerie, shirts, and swimwear).
Electrical insulation materials.
Hosieries (e.g., stockings, socks, and tights).
Fishing lines.
Machine parts (e.g., bearings and gears).
Nets.
Nylon fishing lines.
Parachutes.
Ropes.
Seat belts.
Tarpaulins.
Tents.
Threads.
Advantages of Nylon Material
1.Durability and High Tensile Strength
Nylon is known for its durability and high tensile strength. Based on the finish you’ve chosen, nylon can maintain its color and freshness for a longer period of time compared to other materials. As a result, it’s suitable for applications that need materials that can withstand impacts and resist breaking under high tension.
2. Versatility
How nylon’s atoms (the basic building blocks of all matter) are arranged and bonded together give it its distinctive properties, including its versatility. This allows it to be easily molded into various shapes and forms, which makes it a suitable option for making different products, such as car parts, packaging materials, and textiles.
3. Moisture Resistance
Nylon has excellent moisture-wicking properties because of its molecular structure, which consists of strongly bonded, interlinked chains. These chains form a barrier that prevents water from easily passing through a material.
Types of Nylon
Nylon has different types, each with its own unique properties and uses. Here are some of the common types:
1. Nylon 6
Nylon 6 is derived from caprolactam, which is a chemical compound mainly used for manufacturing man-made fibers, such as brush bristles. This type of nylon is known for its high temperature resistance, excellent toughness and ability to withstand abrasions and chemicals..
Some of the common uses of nylon 6 include:
Combs.
Films.
Industrial machinery.
Packaging materials.
Sheets
Toothbrushes.
Utensils.
Vehicle components.
2. Nylon 6,9
Nylon 6,9, also spelled as nylon 6/9, possesses a wide range of great qualities, making it great for various applications. It has a high melting point and excellent insulation properties. Due to its moderate moisture absorption capacity, it maintains its original size and shape even when it’s exposed to humid conditions. Like nylon 6, it has strong resistance to harsh chemicals, such as acids.
Some of the common uses of nylon 6,9 include:
Automotive parts: engine covers and fuel lines.
Buckles.
Conveyor belts.
Electrical components: insulators and switches.
Gaskets.
Handles.
Seals.
Zippers.
3. Nylon 4,6
With a melting point of approximately 509°F (265°C), nylon 4,6 doesn’t break down easily in high-temperature environments. This variation of nylon also provides good chemical stability compared to other nylon types. But when it comes to impact resistance, it’s not at the same level as some nylons.
Some of the common uses of nylon 4,6 include:
Chemical processing equipment.
Electrical components: circuit breakers and connectors.
Industrial machinery.
Parts for appliances, power tools, and sports equipment.
Pipelines for oil and gas.
4. Nylon 6,10
The structure of nylon 6,10 is able to withstand extreme temperatures without causing serious damage. In addition, it demonstrates exceptional tensile strength, making it an ideal choice for applications that need materials with outstanding strength and load-bearing capacities.
Some of the common uses of nylon 6,10 include:
Automotive parts: air intake manifolds and radiator end tanks.
Electrical components: connectors and terminals.
Sports equipment: racket frames and bicycle parts.
Mechanical parts: bearings and gears.
5. Nylon 66
The primary compounds for making nylon 66 are adipic acid (a colorless, crystal-like substance) and hexamethylenediamine (the same chemical compound in epoxy resins). Similar to other nylon types, it’s valued for its exceptional strength and firmness. This makes it a great option for many applications and production processes that need strong structure, the ability to support heavy loads, and chemical resistance.
The fibers of nylon 66 have a high abrasion resistance, which makes it better than nylon 6. When the temperature is high—for instance, around 356°F—nylon 66 has outstanding heat-age strength retention at 25.35 lbs. This is in contrast to nylon 6, which only demonstrates 5.51 lbs.
Some of the common uses of nylon 66 include:
Backpacks.
Footwear.
Household appliances.
Industrial parts: bearings, bushings, and rollers.
Luggage.
Sportswear.
Synthetic fabrics for carpets, textiles, and threads.
Vehicle components: airbags, engine covers, and fuel lines.
6. Nylon 6,12
Nylon 6,12 sets itself apart from other types of nylon through its chemical structure. Since it has more carbon atoms in its structure, it’s better at not absorbing water compared to other nylon types.
In addition, it’s known for its exceptional dimensional stability. This simply means that it can maintain its shape and size well even when it’s under stress. This characteristic is crucial for products that require precise dimensions in order to work properly and avoid issues such as shrinking and warping.
Some of the common uses of nylon 6,12 include:
Consumer products: kitchen utensils, outdoor furniture, tennis racket strings, tents, and vacuum cleaner parts.
Medical equipment: catheters, medical tubing, and surgical instruments.
Electrical components: connectors, insulators, and switches.
Vehicle components: air brake components, engine covers, and wire insulation.
7. Nylon 12
Nylon 12, also called PA 12, is a strong and versatile plastic that doesn’t break easily. It has been a popular material among injection molders for its exceptional mechanical properties. In recent years, it has become a popular choice for 3D printing to make functional parts and prototypes.
Some of the common uses of nylon 12 include:
Brake system parts.
Cable ties.
Fuel lines.
Prosthetic devices.
Sporting goods.
Wire insulation.
Common Properties of Polyamides
Polyamides have a long list of properties that make them useful in a wide range of industries. The polyamide material properties will vary for each type of polyamide. For the sake of discussion, let’s go over some of the basic properties of polyamide 6 (PA6) and polyamide 66 (PA66).
Great ability to resist deformation or breakage under sudden loading or impact.
Impressive stiffness and strength, even at high temperatures.
Flow easily during processing, such as extrusion or injection molding, to produce high-quality finished products.
Outstanding resistance to abrasion, fatigue, and wear to ensure longevity.
Good resistance to many substances, such as fuel and oil.
Getting easily damaged by strong mineral acids and polar solvents (which are substances that dissolve things, such as acetone and water).
Require proper drying before processing to ensure quality.
Common Properties of Nylon
Like polyamides, nylon has several remarkable properties that make it a popular material for various applications. It even shares a few properties with other polyamide types.
Variation of luster, which can range from dull, semi-lustrous, or highly lustrous.
Capable of withstanding stretching without easily breaking or sustaining deformation.
Has excellent chemical resistance.
Resists damage caused by oils.
Can recover its original shape after being compressed, deformed, or pulled.
Doesn’t soak up water and dries quickly.
Difference Betweens Nylon and Polyamide
Here’s the truth: Polyamide and nylon are the same thing. Nylon is actually a subcategory of polyamides, like how buses and sedans are types of vehicles.
But, as you might expect, they have several differences. The main difference is that polyamides can be natural or synthetic, while nylon material is completely synthetic.
When it comes to moisture-wicking properties, nylon takes the upper hand. It’s greatly resistant to moisture and rain. Meanwhile, polyamides are only less resistant and slightly hydrophobic (don’t mix with water).
The chemical structures of the two materials are also different. Nylon’s chemical structure is highly polar and symmetrical. When it comes to polyamides, it depends on the specific arrangement of parts in their molecule (the smallest unit of a chemical compound).
What do we mean by “polar” and “symmetrical”?
When a compound is polar, you can think of it in terms of magnets—one end of its molecule has a negative charge and the other end has a positive charge.
Symmetrical, on the other hand, refers to the parts of polyamides or nylons that are arranged in a balanced and uniformed way.
Conclusion
Polyamide vs nylon: which is better?
Again, nylon is a synthetic fabric or material that consists of polyamides. They’re the same thing, with only slight differences.
So, the choice between the two compounds will mainly depend on your purpose and specific requirements, as both present comparable performance characteristics. But if you’re looking for a material that’s affordable, easier to process, and possesses a better balance of properties, nylon is a good option.
Author
Gavin Leo is a technical writer at Aria with 8 years of experience in Engineering, He proficient in machining characteristics and surface finish process of various materials. and participated in the development of more than 100complex injection molding and CNC machining projects. He is passionate about sharing his knowledge and experience.