GPPS or HIPS? Decide using flow, Vicat and impact strength
PS Selection · 2026year9month28day
The most common mistake when sourcing PS is looking only at MFR. GPPS selection focuses on transparency, rigidity and surface quality; HIPS selection focuses on impact resistance and housing toughness. Both must be assessed together with Vicat, flexural modulus, impact and application temperature.
Transparent packaging, disposable containers and electronic housings often require different grade-selection logic.
Typical comparison from the official catalog
| Type / Grade | MFR Conditions | Vicat | Other Typical Indicators |
|---|---|---|---|
| GPPS 1160 | 2.4 g/10 min，200°C/5 kg | 101°C | Flexural Modulus 2900 MPa |
| GPPS 1540 | 12 g/10 min，200°C/5 kg | 86°C | Flexural Modulus 2900 MPa |
| HIPS 3450 | 7 g/10 min，200°C/5 kg | 95°C | Notched Izod 8 kJ/m² |
| HIPS 3630 | 15 g/10 min，200°C/5 kg | 82°C | Notched Izod 6 kJ/m² |
The same catalog shows that GPPS 1160 has a higher Vicat than 1540, while 1540 has a higher MFR. HIPS 3450 offers a different balance of impact and heat resistance from high-flow 3630. High flow does not automatically mean better overall performance; the key question is whether the part requires thin-wall mold filling.
GPPS and HIPS selection logic
- When transparency, stiffness and appearance are priorities: Prioritize GPPS and focus on light transmittance, haze, Vicat and residual stress.
- For housings, toys and household products: Prioritize HIPS and focus on notched impact, weld lines and drop performance.
- For high-speed thin-wall injection molding: Higher-flow grades may be considered, but flash, shrinkage, warpage and part strength must be validated.
- For hot-fill applications or parts near heat sources: Evaluate Vicat together with the actual load temperature; do not look only at the material's MFR.
Confirm test conditions when sourcing
PS documentation commonly reports MFR at 200°C/5 kg. It must not be compared directly with PP at 230°C/2.16 kg or PC at 300°C/1.2 kg. Specify the test method, load, temperature, color and whether recycled content is included in the inquiry; food-contact and medical packaging also require the appropriate compliance declarations.
Reference Documentation
Parameters reference the TotalEnergies Polymers official product catalog: TotalEnergies PS product catalog; it lists typical MFR, Vicat and impact data for GPPS 1160, 1540 and HIPS 3450, 3630. Actual data is subject to the latest TDS for the target grade.
Need GPPS / HIPS grade guidance?
Tell us whether the product is a transparent part, housing or packaging, and we will match grades to the flow and impact requirements.