Comprehensive technical data on nylon/PA material properties — thermal, mechanical, chemical resistance, electrical, and comparison tables across grades.
Overview of Nylon Material Properties
Nylon (polyamide) materials occupy a unique position in engineering thermoplastics: they offer the highest combination of strength, toughness, and wear resistance among non-reinforced plastics, while remaining processable on standard injection molding and extrusion equipment. This technical reference compiles the key properties that engineers, designers, and procurement specialists need when evaluating nylon for specific applications.
All data in this reference applies to conditioned material (23°C, 50% RH) unless otherwise noted. Moisture content significantly affects mechanical properties — dry-as-molded values can be 20-40% higher than conditioned values for unfilled nylon.
Mechanical Properties by Nylon Grade
**Tensile Properties**:
| Property | PA6 | PA66 | PA46 | PA12 | PA6-GF30 | PA66-GF30 |
|—|—|—|—|—|—|—|
| Tensile Strength (MPa) | 80 | 82 | 90 | 55 | 170 | 185 |
| Elongation at Break (%) | 150 | 60 | 45 | 200 | 3 | 3 |
| Tensile Modulus (GPa) | 2.8 | 3.0 | 3.2 | 1.7 | 9.0 | 10.0 |
| Flexural Strength (MPa) | 100 | 110 | 130 | 75 | 240 | 270 |
| Flexural Modulus (GPa) | 2.6 | 2.8 | 2.9 | 1.6 | 8.5 | 9.2 |
| Notched Izod Impact (J/m) | 55 | 45 | 60 | 45 | 100 | 105 |
| Unnotched Izod (J/m) | No break | No break | 450 | No break | 600 | 700 |
**Key Observations**:
– PA6 has higher elongation (more ductile) but PA66 has higher strength
– Glass fiber reinforcement (GF30 = 30% glass fiber) increases strength 2-2.5× but dramatically reduces ductility
– PA46 outperforms all standard nylons in both strength and thermal resistance, at higher cost
– PA12 is the softest and most flexible — lowest strength but best impact resistance at low temperatures
Thermal Properties
Thermal performance is often the deciding factor in grade selection:
| Property | PA6 | PA66 | PA46 | PA12 | PA6-GF30 |
|—|—|—|—|—|—|
| Melting Point (°C) | 225 | 265 | 295 | 180 | 225 |
| Glass Transition Temp (°C) | 50-60 | 65-70 | 75 | 40-45 | 50-60 |
| HDT @ 0.45 MPa (°C) | 170 | 250 | 285 | 145 | 215 |
| HDT @ 1.82 MPa (°C) | 65 | 90 | 160 | 55 | 195 |
| Continuous Service Temp (°C) | 100-115 | 130-150 | 170-180 | 80-95 | 140-160 |
| Thermal Conductivity (W/m·K) | 0.25 | 0.25 | 0.30 | 0.23 | 0.47 |
| Specific Heat (J/g·K) | 1.7 | 1.7 | 1.4 | 1.6 | 1.3 |
**HDT Notes**:
– Heat Deflection Temperature (HDT) measures temperature at which a specimen deflects 0.25mm under specified load
– Glass fiber reinforcement dramatically improves HDT — GF30 grades achieve 2-3× the HDT of unfilled grades at 1.82 MPa
– PA66-GF30 at 1.82 MPa: 250°C — suitable for under-hood automotive applications
– PA12’s low HDT limits use to room-temperature applications
Moisture Absorption and Environmental Effects
Nylon’s moisture absorption is a critical consideration — more so than almost any other engineering plastic:
| Grade | Moisture Absorption (24h, 50% RH) | Moisture Absorption (saturation, 23°C/50% RH) | Equilibrium Humidity |
|—|—|—|—|
| PA6 | 1.6% | 9.5% | 2.5-3.0% |
| PA66 | 1.2% | 8.5% | 2.5% |
| PA46 | 1.2% | 6.5% | 2.0% |
| PA12 | 0.3% | 1.5% | 0.7% |
| PA11 | 0.4% | 2.0% | 0.8% |
**Impact of Moisture on Properties**:
– Tensile strength decreases 15-25% at saturated condition vs. dry-as-molded
– Impact resistance INCREASES with moisture absorption (nylon becomes tougher when conditioned)
– Dimensional change: PA6 swells approximately 0.4% per 1% moisture absorbed — must be accounted for in precision parts
– Electrical insulation properties degrade significantly with moisture (dielectric constant increases 2×)
**Design Recommendations**:
– PA12 for parts exposed to humid environments or water immersion
– Dry-as-molded properties for designing dimensional tolerances in molds
– Condition parts to equilibrium before measuring critical dimensions
Chemical Resistance of Nylon
Nylon’s chemical resistance profile determines suitability for industrial environments:
**Good Resistance (no significant attack at 23°C)**:
– Aliphatic hydrocarbons (gasoline, mineral oils, diesel)
– Alcohols (methanol, ethanol, isopropanol)
– Esters and ketones (acetone, MEK — limited exposure)
– Weak acids (acetic acid, citric acid — verify case-by-case)
– Dilute alkalis and salts
**Poor Resistance (attack or degradation)**:
– Concentrated mineral acids (HCl, H2SO4, HNO3) — rapid hydrolysis
– Strong oxidizing agents (hydrogen peroxide >10%)
– Phenol and formic acid — dissolves nylon
– Calcium chloride (desiccant) — causes stress cracking
– Strong alkalis at elevated temperature
**Specialty Grades for Chemical Service**:
– PA12 for automotive fuel lines — resistant to aromatic fuels and alcohol blends
– PA6I/6T (transparent nylon) for chemical contact applications requiring clarity
– Glass-filled grades for chemical pump housings and valve components
Electrical and Flammability Properties
**Electrical Properties** (at 50% RH conditioning):
| Property | PA6 | PA66 | PA12 |
|—|—|—|—|
| Dielectric Strength (kV/mm) | 20 | 20 | 18 |
| Volume Resistivity (Ω·cm) | 10^15 | 10^15 | 10^14 |
| Surface Resistivity (Ω) | 10^13 | 10^13 | 10^12 |
| Dielectric Constant (1 MHz) | 3.8 | 3.6 | 3.1 |
| Dissipation Factor (1 MHz) | 0.02 | 0.02 | 0.03 |
**Flammability Ratings**:
| Grade | UL94 Rating | Oxygen Index (%) |
|—|—|—|
| PA6 | HB | 24 |
| PA66 | HB | 24 |
| PA12 | HB | 22 |
| PA6-GF30 | HB | 23 |
| FR grades | V-0 | 32+ |
Nylon burns with a self-sustaining flame and drips. For electrical enclosures or components requiring flame retardancy, specify FR (flame retardant) grades — typically PA66 with halogen or phosphorus-based flame retardants.
Whether you need technical guidance on selecting the right nylon grade for your specific application, or want to discuss pricing and supply options for PA6-CF, PA66-GF, or standard nylon materials, our engineering team is ready to help. Nylonplastic.com supplies industrial-grade nylon materials to manufacturers in North America, Europe, and Southeast Asia.
Get a Free Material Consultation →
Contact our technical team for nylon grade recommendations, pricing for bulk orders, or samples for testing. We supply PA6-CF carbon fiber reinforced nylon in 1.75mm and 2.85mm diameters, plus full range of PA6, PA66, PA12, and GF-reinforced grades.
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**FAQs**
**Q: What is the difference between PA6 and PA66?**
A: PA66 (nylon 66) has a higher melting point (265°C vs. 225°C) and better chemical resistance than PA6. PA6 offers better impact resistance and is more cost-effective. PA66 is preferred for high-temperature and under-hood automotive applications; PA6 is common for general engineering.
**Q: How much does glass fiber reinforcement improve nylon?**
A: Adding 30% glass fiber increases tensile strength by 100-120% (from ~80 MPa to ~170 MPa) and flexural modulus by 250-300% (from ~2.8 GPa to ~9 GPa). However, it also reduces impact resistance and increases warpage.
**Q: What is carbon fiber reinforced nylon used for?**
A: Carbon fiber reinforced nylon is used for structural components requiring high stiffness-to-weight ratio, ESD-sensitive applications (electronics packaging, fuel systems), and precision parts requiring dimensional stability. nylonplastic.com supplies PA6-CF for FDM 3D printing and injection molding applications.
**Q: How do I prevent moisture absorption problems in nylon parts?**
A: Dry nylon resin to below 0.2% moisture content before molding (4-6 hours at 80-85°C in desiccant dryer). For dimensional-critical parts, anneal after molding (1-2 hours at 120-130°C) to stabilize crystallinity. Use glass or carbon fiber reinforcement to reduce moisture-induced dimensional change by 70-80%.
**Q: Can nylon be used for food contact applications?**
A: Yes. Both PA6 and PA66 have FDA 21 CFR §177.1500 compliance for food contact. EU Regulation 10/2011 compliance requires specific compound selection with documented SML testing. Always verify specific grade compliance with your supplier.
