Polyamide vs Nylon: Everything You Need to Know

Polyamide and nylon are terms often used interchangeably, but they’re not exactly the same. Polyamide refers to a broader family of polymers that contain repeating amide bonds. These materials can be either natural (like proteins) or synthetic. Nylon, by contrast, is a specific type of synthetic polyamide first developed by DuPont in the 1930s.[1]

In other words, all nylons are polyamides, but not all polyamides are nylons. Nylon was originally created as a substitute for silk in textiles—rummage through a closet in the 1960s and you’d find yourself swimming in the stuff—but today it’s widely used in everything from clothing and carpets to mechanical components and 3D printing filaments. Other types of polyamides, like aramids, can offer different properties such as high heat resistance or added strength.

Knowing the difference between nylon and (other) polyamides helps in choosing the right material for the job. This guide looks at the main differences between nylon and other polyamides, helping you decide which material is best for a given application or manufacturing process.

Polyamide Vs Nylon: Key Differences

A woven nylon belt, showcasing the material's use as a synthetic textile

Polyamides are a broad class of polymers defined by amide linkages (-CONH-) in their molecular backbone.[2] Nylon is a specific subset of synthetic aliphatic polyamides. As we mentioned in the introduction, all nylons are polyamides, but not all polyamides are nylons. Other types of polyamide include high-performance materials like aramids (e.g. Kevlar) and semi-aromatic polyphthalamides (PPA), which offer enhanced thermal and mechanical properties for demanding applications.[3]

All polyamides share a backbone of repeating amide units formed through condensation polymerization, but the specific “R” group in their structure affects traits like flexibility and strength. Nylon 6 and Nylon 66, the most common types of nylon, are synthesized differently and show distinct mechanical behavior. Nylons typically exhibit moderate crystallinity, balancing toughness and flexibility. On the other hand, aramids, with much higher levels of crystallinity, provide better heat resistance and strength. Moisture absorption differs, too: nylons can absorb up to 8.5% water, while aramids absorb less than 1%, making them better for high-precision or high-temperature uses.

The table below shows some of the more common polyamides used by engineers, including several nylons.

Choosing Between Nylon and Other Polyamides

Picking the right polyamide—whether it’s a standard nylon or a more specialized type—depends on your project’s performance needs, budget, and environment. Engineers can follow a simple step-by-step process to match the material with the job. This involves checking strength, temperature range, exposure to moisture or chemicals, and how easy the material is to work with during manufacturing.

Quick selection checklist:

• Define key needs: strength, heat resistance, impact toughness, and chemical exposure
• Use standard test data to compare materials (look for strength and impact ratings)
• Consider the environment: moisture levels, UV exposure, and temperature swings
• Balance cost vs. performance (basic nylons are cheaper; high-end polyamides cost more but perform better)
• Match the material with your manufacturing method (e.g., injection molding or 3D printing) and required equipment settings

Polyamide Vs Nylon Applications

Nylon is a versatile synthetic polymer widely used across industries due to its strength, flexibility, abrasion resistance, and chemical stability.[4] Its ability to perform well under mechanical stress and varying environmental conditions makes it suitable for both consumer products and engineering applications. Believe it or not, your bathing suit could be made from the same material as the gears in your swimming pool pump system.

Common applications of nylon include:

• Automotive parts: engine covers, cable ties, air intake manifolds

• Textiles: clothing, hosiery, backpacks, parachutes

• Industrial components: gears, bushings, rollers, bearings

• Consumer goods: toothbrush bristles, kitchen utensils, fishing lines

• Electrical and electronics: wire insulation, connectors, housings

• 3D printing: functional prototypes and end-use parts (Nylon 12, Nylon CF)

• Medical devices: surgical sutures, catheters (using biocompatible grades)

Beyond nylon, other polyamides—such as aramids, polyphthalamides (PPA), and bio-based variants—can serve in demanding applications where higher heat resistance, strength, or chemical stability is needed. These materials are commonly used in specialized fields like aerospace, automotive, and electronics, where standard nylons may fall short in performance.

Applications of non-nylon polyamides include:

• Aramids (e.g., Kevlar®, Nomex®): body armor, flame-resistant clothing, aerospace composites

• Polyphthalamides (PPA): under-the-hood automotive parts, fuel system components, high-temperature connectors

• PA6T/6I and similar semi-aromatic blends: electrical housings, appliance parts exposed to heat

• Bio-based polyamides (e.g., PA11): pneumatic tubes, sports gear, flexible industrial hoses

• PA46 and PA9T: high-load gears, precision mechanical components, brake systems

• High-temperature polyamides: LED lighting components, turbocharger parts, electronic chip carriers

Manufacturing With Nylon and Other Polyamides

SLS 3D printed nylon components

Nylon and other polyamides are widely used in manufacturing and prototyping thanks to their balance of strength, flexibility, thermal stability, and chemical resistance. These materials can be processed using a variety of methods, each suited to different scales of production (e.g., prototyping vs mass production) and application requirements.

Injection Molding

Injection molding is the most common method for producing nylon and polyamide parts in high volumes. It involves melting granulated polymer and injecting it into a mold cavity under pressure. Nylon 6 and Nylon 66 are widely used due to their excellent flow properties and mechanical strength. 

Glass-filled variants can be used to enhance stiffness and heat resistance, although they increase tool wear and may require higher injection temperatures (typically 220–300°C for standard grades). For specialty polyamides like PPA or aramids, processing temperatures can exceed 350°C, requiring more robust equipment and tooling.

CNC Machining

CNC machining is frequently used for low-volume production, prototypes, or applications that require tight tolerances. Nylon can be machined using standard carbide tools, although its softness compared to metals can lead to issues like material deformation or tool buildup. Dry machining can prevent some of these issues. 

Machining aramids or glass-filled polyamides requires more care due to their abrasive nature, which can lead to increased tool wear. Common CNC applications include bushings, spacers, and precision housings.

3D Printing

Additive manufacturing with nylon—especially Nylon 12 and carbon-fiber-filled variants—is growing rapidly in prototyping and end-use parts. Selective Laser Sintering (SLS) is the dominant method for printing nylon, offering excellent resolution, good surface finish, support-free printing, and isotropic strength properties. Popular SLS materials include:

• HP 3D High Reusability PA 12 (by HP)

• EOS PA 1101 (by EOS)

• BASF Ultrasint® PA12 GF (by BASF Forward AM)

Fused Filament Fabrication (FFF/FDM) is also common, though it typically results in weaker parts unless reinforced with materials like glass or carbon fiber. PA11, a bio-based polyamide, is used increasingly in 3D printing due to its flexibility and low moisture absorption. These materials are ideal for creating functional parts, jigs, fixtures, and housings. Example filament products include:

• MatterHackers NylonX (by MatterHackers)

• Polymaker PolyMide™ CoPA (by Polymaker)

• BASF Ultrafuse® PA (by BASF Forward AM)

Extrusion

Extrusion is used for producing continuous profiles like tubing, films, and fibers. Nylon’s strength and wear resistance make it ideal for extruded products such as fishing lines, fuel lines, and pneumatic tubing. However, processing conditions need to be carefully controlled to minimize moisture uptake before extrusion, as absorbed water can cause foaming or surface defects. 

Polyamides like PA11 and PA12 are often used in flexible tubing due to their better chemical resistance and lower water absorption compared to Nylon 6 or 66.

Recommended reading: Strongest 3D Printer Filament: Choosing Between PC, Nylon, TPU, and Others

Reinforced and Blended Nylon and Polyamide

Composites and blends are engineered to boost performance by combining the base material with reinforcing materials or additives. Glass fiber-reinforced nylon increases stiffness, strength, and thermal resistance, making it ideal for automotive parts, appliance housings, and structural components. Carbon fiber-reinforced nylon offers even greater strength-to-weight ratios and thermal stability, and you’ll find it used in aerospace, drones, and high-performance tools. These composites are valued where lightweight durability is essential.

Other polyamides—not just nylons—can also be reinforced. Polyphthalamides (PPA) and aramids are often combined with glass fibers, carbon fibers, or mineral fillers to push mechanical and thermal limits even further. These reinforced high-performance polyamides are used in electrical connectors, fuel systems, and under-the-hood automotive parts where extreme heat and stress are present.

Blended polyamides, such as nylon-PBT or nylon-polyolefin blends, are tailored to improve impact resistance, reduce moisture absorption, or enhance chemical compatibility. These blends find roles in electronics, plumbing, and consumer products.

Both reinforced nylons and other polyamides are compatible with injection molding and, increasingly, with 3D printing. Carbon fiber-filled nylon filaments are popular for creating strong, functional prototypes and low-volume end-use parts, allowing engineers to replace metals in lightweight, durable applications.

Recommended reading: Glass-Filled Nylon: The Properties and Benefits

Mistakes to Avoid When Using Polyamide and Nylon

Choosing the wrong type of polyamide can lead to costly redesigns and delayed timelines. These issues often arise from overlooked material behavior under real-world conditions. We’ve identified five common pitfalls that are responsible for many of the failures in polyamide and nylon manufacturing.

Top 5 polyamide/nylon pitfalls:

1. Moisture Absorption: Standard nylons can swell and weaken, so use low-absorption types like PA12 or specify dry-as-molded properties.

2. Temperature Limits: Always design below the material’s heat deflection point and account for humidity-related shifts in glass transition temperature.

3. Impact Misjudgment: Test materials at their minimum service temperature, not just at room temperature, to ensure toughness under all conditions.

4. UV Sensitivity: Nylons degrade in sunlight, so choose UV-stabilized grades or switch to aromatic polyamides for outdoor use.

5. Improper Drying: Residual moisture during processing causes polymer degradation; follow recommended drying times and temperatures.

Recent Developments

Recycling of nylon is an increasing concern for manufacturers

In 2025, polyamide and nylon material development is often focused on sustainability and advanced recycling methods. Significant investments are driving the development of bio-based polyamides, which aim to reduce carbon footprints by using renewable raw materials or recycled content. For example, BASF’s Ultramid LowPCF uses biomass balance approaches to lower environmental impact. Aquafil’s ECONYL process chemically recycles waste fishing nets into high-quality nylon.

Enzyme-based recycling technologies, like those developed by Samsara Eco, break down nylon into original monomers with high recovery rates, supporting circular economy goals. Meanwhile chemical recycling, unlike mechanical recycling, helps maintain virgin-like material properties even after multiple cycles.

Material enhancements are also advancing, with carbon nanotube reinforcement and nano-titanium dioxide additives improving strength, heat resistance, and weight savings. Production costs for nano-enhanced materials have also decreased, making them more competitive with imports.

Conclusion

In conclusion, while nylon is a well-known member of the polyamide family, especially in forms like polyamide 6 and nylon 66, it's just one part of a broader group of thermoplastic materials defined by amide groups and a shared chemical structure. Thanks to their strong tensile strength, high temperature resistance, and adaptable molecular structure, both nylon and other polyamides are widely used in engineering plastics, synthetic fibers, and industrial applications. Their versatility across various applications—from textiles to components exposed to heat, moisture, and solvents—continues to make them valuable materials in modern manufacturing.

Frequently Asked Questions

What is the main difference between polyamide and nylon?

Polyamide is a broad family of polymers with amide bonds, while nylon specifically refers to aliphatic polyamides like PA6 and PA66. All nylons are polyamides, but not all polyamides are nylons.

Which material performs better for automotive applications?

PA66 usually performs better due to its higher melting point, improved chemical resistance, and lower moisture absorption compared to PA6, with similar costs.

How do testing standards differ for polyamides?

ASTM D6779 classifies all polyamide types, while ISO 527-2 and ASTM D638 measure tensile properties. Differences mainly appear in heat and chemical resistance tests.

What are the costs and benefits of high-performance polyamides?

High-performance polyamides like PPA cost more but offer superior heat resistance and chemical durability, making them suitable for electronics and demanding uses.

References

[1] Morgan PW. Brief history of fibers from synthetic polymers. Journal of Macromolecular Science—Chemistry. 1981 Apr 1;15(6):1113-31.

[2] Ali MA, Kaneko T. Polyamide syntheses. Encyclopedia of polynanomeric materials. Springer, Berlin. 2015:1750-62.

[3] Cheng M, Chen W, Weerasooriya T. Mechanical properties of Kevlar® KM2 single fiber. J. Eng. Mater. Technol.. 2005 Apr 1;127(2):197-203.

[4] More A, Maurya P, Ubhale Y. Nylon fiber: composites and applications. InSynthetic and Mineral Fibers, Their Composites and Applications 2024 Jan 1 (pp. 101-149). Woodhead Publishing.