This nylon 6 nylon guide explains practical considerations for material selection, design review, manufacturing, and sourcing decisions.
Nylon 6 vs Nylon 66 is one of the most common engineering plastic comparisons because the best choice depends on moisture exposure, strength targets, heat load, and processing needs.
In short, Nylon 6 is often preferred for toughness, easier processing, and lower cost, while Nylon 66 is usually chosen when higher heat resistance, stiffness, and creep performance matter more. For reinforced grades, see our PA66 GF30 guide and for fluid exposure, compare nylon chemical resistance.
Chemical Structure Differences
The fundamental difference between PA6 (nailon 6) y PA66 (nailon 66) lies in their molecular structure:
- Nylon 6: Made from caprolactam, has 6 carbon atoms in each repeating unit. Less crystalline structure.
- Nylon 66: Made from hexamethylenediamine and adipic acid, has two 6-carbon chains. More crystalline structure.
Comparación de propiedades mecánicas
| Propiedad | PA6 | PA66 |
|---|---|---|
| Resistencia a la tracción | 70-85 MPa | 80-100 MPa |
| Módulo de flexión | 2.5-3.0 GPa | 2.8-3.5 GPa |
| Alargamiento a la rotura | 30-100% | 15-60% |
| Resistencia al impacto Izod con muesca | 50-100 J/m | 40-80 J/m |
| Punto de fusión | 220 °C | 260 °C |
| HDT a 1,8 MPa | 70°C | 90°C |
Absorción de humedad
Moisture absorption is critical for nylon applications:
| Condition | PA6 | PA66 |
|---|---|---|
| At 50% RH | 2.5-3.0% | 2.0-2.5% |
| Saturation | 8-10% | 6-8% |
Processing Characteristics
Nylon 6 Processing
- Punto de fusión: 220 °C
- Processing Range: 240-280°C
- Temperatura del molde: 40-80°C
Nylon 66 Processing
- Punto de fusión: 260 °C
- Processing Range: 280-320°C
- Temperatura del molde: 60-90°C
Applications by Material
Nylon 6 Applications
- Gears and sprockets
- Industrial monofilament
- Film and packaging
- Consumer products
Nylon 66 Applications
- Automotive under-hood components
- Electrical connectors
- High-temperature bearings
- Precision mechanical components
Reinforced Grades
Both materials are commonly reinforced with glass fiber:
| Grado | PA6 + GF30 | PA66 + GF30 |
|---|---|---|
| Resistencia a la tracción | 140-160 MPa | 170-200 MPa |
| HDT (1,8 MPa) | 205°C+ | 250°C+ |
| Absorción de humedad | 1.0-1.5% | 0.8-1.2% |
Selection Summary
Choose Nylon 6 when:
- Impact resistance is critical
- Cost sensitivity is high
- Operating temperatures are moderate
Choose Nylon 66 when:
- Higher mechanical strength is required
- Elevated temperatures are expected
- Dimensional stability is critical
PREGUNTAS FRECUENTES
When is Nylon 6 vs Nylon 66 — Engineering Plastic Selection Guide a good option?
Nylon 6 vs Nylon 66 — Engineering Plastic Selection Guide is a good option when fast iteration, complex geometry, low tooling cost, or low-volume production is more important than molded-part unit cost.
What should be checked before choosing Nylon 6 vs Nylon 66 — Engineering Plastic Selection Guide?
Compruebe el tamaño de la pieza, las propiedades del material, el acabado superficial, la tolerancia dimensional, la exposición al calor, la dirección de la carga y si es necesario un tratamiento posterior.
How does Nylon 6 vs Nylon 66 — Engineering Plastic Selection Guide compare with CNC machining?
La impresión 3D puede crear formas complejas con rapidez, mientras que el mecanizado CNC suele ser más potente para superficies precisas, tolerancias más ajustadas y materiales de calidad de producción.
What affects the cost of Nylon 6 vs Nylon 66 — Engineering Plastic Selection Guide?
El coste depende del material, el volumen de fabricación, el tiempo de impresión, la altura de capa, la eliminación de soportes, el acabado, la inspección y el número de piezas de la fabricación.
Lecturas relacionadas
- Nylon vs Polipropileno: Guía de selección de materiales para aplicaciones de ingeniería
- Acetal POM vs Nylon - ¿Qué plástico de ingeniería es el adecuado para su aplicación?
- Nylon frente a PBT: comparación completa de termoplásticos de ingeniería
At a Glance
| Decision Point | PA6 | PA66 | Buyer Note |
|---|---|---|---|
| Impact / toughness | Fuerte | Fuerte | Compare actual part loading, not just resin family |
| Resistencia al calor | Bien | Usually better | PA66 often wins when temperature margin matters |
| Moisture response | Más alto | Also high | Conditioning will affect both grades |
| Best use | General engineering parts | Hotter or more demanding parts | Use the part environment to decide the grade |
Why Choose Nylon Plastic
Nylon Plastic can help buyers separate PA6 and PA66 decisions when the part needs a practical balance of heat, toughness and molding cost.
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