GETA QUOTE
Red Phosphorus Flame Retardant (Microcapsule Encapsulated Red Phosphorus)
Red phosphorus hydrolyzes at high temperature to form phosphoric acid and polymetaphosphoric acid, which promotes char formation in the condensed phase to block heat and oxygen. V0 rating can be achieved at a low loading level (5~9%).
Drawback: Red phosphorus slowly generates phosphine (PH₃) in humid environments and forms acidic substances that corrode metal terminals. There is a risk of blooming during long-term 85℃/85%RH aging, depending on encapsulation quality.
Composite Phosphorus-Nitrogen Flame Retardant (ADP + Nitrogen Synergist)
Phosphorus (ADP) quenches free radicals in gas phase while nitrogen sources foam and expand. It works via synergistic expansion charring in both gas and condensed phases.
Higher total flame retardant loading (12~20%). V0 is realized by multi-component blending; no elemental red phosphorus is contained.
| Item | Red Phosphorus Flame Retardant PA66GF30 V0 | Composite Phosphorus-Nitrogen Flame Retardant PA66GF30 V0 |
|---|---|---|
| Color | Only black/dark grey; not available in natural/light colors | Natural, white or custom colors; flexible color matching |
| Flame Retardant Loading | Low (5~9%), less deterioration on mechanical properties | Relatively high (12~20%), reduced impact strength and flowability |
| CTI | Typically 450~500V; high-grade encapsulated grade up to 550V+ | Higher CTI, ≥600V normally, preferred for high-voltage electrical and charging pile parts |
| Hydrothermal / 85℃/85%RH Aging | Poor. Risk of blooming and metal terminal corrosion under long-term high temperature & humidity; improved with better encapsulation | Excellent. Minimal blooming risk, barely corrodes copper terminals |
| Smoke Density | Low smoke | Low smoke, less acidic gas released during combustion |
| Mechanical Properties | Higher tensile/flexural modulus, good rigidity, high impact retention | Slightly lower modulus and notched impact strength at same glass fiber content |
| HDT | High, 220~235℃ | Slightly lower than red phosphorus system |
| Processing | Good flowability; strict moisture control required. PH₃ may release with high moisture | Moderate flowability, lubricant formulation adjustment needed; less screw corrosion |
| Cost | Lower price for equivalent V0 grade | Higher cost, 15~35% more expensive |
| Regulation & Environmental Compliance | RoHS compliant; red phosphorus restricted in some automotive, precision electronics and export projects due to PH₃ risk | Better RoHS & REACH compliance. Preferred for new energy and automotive electronics |
3. Pros & Cons Summary
Red Phosphorus PA66GF30
Advantages: High flame retardancy efficiency, good mechanical performance, high HDT, low cost, good flowability.
Disadvantages: Color limitation; risk of phosphine generation and metal contact corrosion under humid conditions; often restricted for high-end export and new energy projects.
Application: Black low-voltage connectors, relay housings, switch bases, indoor dry environment.
Composite Phosphorus-Nitrogen PA66GF30
Advantages: Natural/colorable grades available; high CTI; stable under long-term 85℃/85%RH; no PH₃; negligible corrosion to metal terminals, better regulatory compliance.
Disadvantages: High flame retardant loading leads to slightly poorer mechanical properties and flowability; higher material cost.
Application: Charging piles, automotive electrical components, home appliances, 5G parts, export components, natural/light color requirement, long-term humid working conditions.
Supplementary note: There is also a red phosphorus + MCA synergistic formula. It is essentially still a red phosphorus system and remains limited by color and PH₃ blooming risk. It shall NOT be regarded as the halogen-free composite flame retardant mentioned above.
4. Selection Guidance
For black parts, dry environment and cost control → Encapsulated red phosphorus PA66GF3。。
For natural/colored grades, high CTI requirement, long-term 85℃/85%RH exposure, new energy/automotive precision terminals and export products → Composite phosphorus-nitrogen flame retardant PA66GF30.
