PP compounds
Halogen-free flame-retardant PP and flame-retardant glass-fiber-reinforced PP.
Example grade / typical values — to be corrected by GREENPOLYMER
Selection criteria
- Density
- Cost
- Stiffness
- Flame retardancy
- GRN-PP-E510Fan parts
- GRN-PP-N510Halogen-free flame-retardant PP
PP (polypropylene) has low density, low cost and good chemical resistance. Standard PP burns easily; with flame retardant it is used for internal parts of home appliances, internal brackets of power supplies and charging equipment, cable ducts and fan parts. With glass fiber its stiffness and heat resistance rise markedly, so it can be used for structural parts that need flame retardancy.
GREENPOLYMER PP grades
| Grade | Key features | Suitable parts |
|---|---|---|
| GRN-PP-N510 | Halogen-free flame-retardant PP | Internal parts of home appliances, cable ducts, internal brackets of power supplies |
| GRN-PP-E510 | Flame-retardant glass-fiber-reinforced PP | Appliance structural parts, fan parts, internal brackets of energy storage equipment |
| Food-contact PP (grade provided per project) | Food contact | Electric kettle bodies and lids, coffee machine water tanks, food-contact appliance parts |
Recycled-content versions (-R) of each grade can be customized.
- Food-contact grades available; compliance testing to GB 4806 and EU Regulation (EU) No 10/2011 can be arranged.
Key properties
Typical values. Refer to the actual TDS.
- DensityISO 1183
- PP-N5101.00–1.10 g/cm³
- PP-E5101.15–1.30 g/cm³
- MFRISO 1133
- PP-N5105–20 g/10 min (230 °C / 2.16 kg)
- PP-E5103–10 g/10 min (230 °C / 2.16 kg)
- Tensile strengthISO 527
- PP-N51020–28 MPa
- PP-E51050–70 MPa
- Flexural modulusISO 178
- PP-N510—
- PP-E5104–6 GPa
- Notched impact (23 °C)ISO 179/1eA
- PP-N5103–6 kJ/m²
- PP-E5105–9 kJ/m²
- HDT (1.80 MPa)ISO 75
- PP-N51055–65 °C
- PP-E510120–145 °C
- Flammability (design target)UL 94
- PP-N510V-0 @ 1.5 mm
- PP-E510V-0 @ 1.5 mm
Full table
| Item | Test standard | GRN-PP-N510 | GRN-PP-E510 |
|---|---|---|---|
| Density | ISO 1183 | 1.00–1.10 g/cm³ | 1.15–1.30 g/cm³ |
| MFR | ISO 1133 | 5–20 g/10 min (230 °C / 2.16 kg) | 3–10 g/10 min (230 °C / 2.16 kg) |
| Tensile strength | ISO 527 | 20–28 MPa | 50–70 MPa |
| Flexural modulus | ISO 178 | — | 4–6 GPa |
| Notched impact (23 °C) | ISO 179/1eA | 3–6 kJ/m² | 5–9 kJ/m² |
| HDT (1.80 MPa) | ISO 75 | 55–65 °C | 120–145 °C |
| Flammability (design target) | UL 94 | V-0 @ 1.5 mm | V-0 @ 1.5 mm |
Flammability ratings are design targets, tested to the UL 94 method (to be verified by GREENPOLYMER). Certificate to be uploaded.
Flame-retardant PP or flame-retardant glass-fiber-reinforced PP
| Situation | Recommended |
|---|---|
| Internal parts with low loads that should be light and low cost | GRN-PP-N510 |
| Structural parts needing stiffness or heat resistance above 80 °C | GRN-PP-E510 |
| Good impact performance needed | Both have fairly low impact; consider PC/ABS |
| Appearance parts | Flame-retardant PP has a modest surface; evaluate it first for appearance parts |
Strengths and limits of PP
Strengths
Low density; low cost; resistant to acids, alkalis and most solvents; no strict drying needed.
Limits
Unreinforced PP has low heat resistance; high shrinkage; flame-retardant PP has fairly low impact; the surface is hard to bond and hard to paint.
Halogen-free flame-retardant PP
Its high flame-retardant loading can affect impact and surface. Watch for flame retardant blooming at high temperature and humidity; damp heat testing is recommended.
Processing advice
Typical values. Refer to the actual TDS.
- Drying
- GRN-PP-N510Usually not needed; if damp, 80 °C, 1–2 h
- GRN-PP-E510Same
- Melt temperature
- GRN-PP-N510190–220 °C (not too high for flame-retardant grades)
- GRN-PP-E510210–240 °C
- Mold temperature
- GRN-PP-N51030–60 °C
- GRN-PP-E51040–70 °C
- Injection speed
- GRN-PP-N510 Medium
GRN-PP-E510 Medium to fast - Residence time
- GRN-PP-N510 As short as possible, to avoid degrading the flame retardant
GRN-PP-E510 As short as possible
Full table
| Item | GRN-PP-N510 | GRN-PP-E510 |
|---|---|---|
| Drying | Usually not needed; if damp, 80 °C, 1–2 h | Same |
| Melt temperature | 190–220 °C (not too high for flame-retardant grades) | 210–240 °C |
| Mold temperature | 30–60 °C | 40–70 °C |
| Injection speed | Medium | Medium to fast |
| Residence time | As short as possible, to avoid degrading the flame retardant | As short as possible |
Design points
High shrinkage
Unreinforced PP shrinks about 1.5–2.0 % (typical value); size the mold to the material's shrinkage.
Glass-fiber-reinforced PP shrinks anisotropically
It warps easily; watch the gate position and keep walls even.
Use ribs instead of thicker walls
Thick walls cause sink marks.
Hinge design (unreinforced PP)
PP suits living hinges, but hinge life in flame-retardant PP must be validated.
FAQ
Can flame-retardant PP replace flame-retardant ABS?
It can be considered for internal parts with no appearance or impact requirements, lowering weight and cost. For appearance parts and parts under impact, validate first.
Is there a food-contact PP?
Yes. Food-contact grades are available, with compliance testing supported to GB 4806 and (EU) No 10/2011 requirements. Tell us the service temperature, contact time, food type and target market; food-contact grades are provided per project.
Can flame-retardant PP be glow-wire tested?
Yes, to the IEC 60695-2-12/13 methods. For appliance parts, tell us the required glow-wire temperature.
Related content
- Applications: Home appliances and cleaning | New energy and energy storage
- Article: How to read a UL 94 flammability rating
Contact us
Tell us the part name, flammability rating and thickness, glow-wire requirements, operating temperature and the expected volume. Phone +86 18822892298 | Email hello@greenpolymer.com