6# Polyester Polyurethane Foam
H-O Products 6# Polyester Polyurethane Foam is an open cell, high density polyester polyurethane foam with a density of 6 lb/ft³ ±10% and a compression force deflection of 0.75 psi average at 25% per ASTM D3574. It is described as a medium firm foam rated for FMVSS-302, UL 94 HF-1 (at 0.12″ minimum thickness), REACH, and RoHS compliance. It delivers the highest compression force deflection at 50% in the series and is suited to acoustical sound absorption and air dam foam and pad applications.
Key Properties
- Compression Force Deflection @ 25%, Average: 0.75 psi (ASTM D3574)
- Tensile Strength (Average): 18 psi (ASTM D3574)
- Elongation (Average): 190% (ASTM D3574)
- Density: 6 lb/ft³ ±10% (ASTM D3574)
- UL 94 HF-1: Pass (at 0.12″ minimum thickness)
- FMVSS-302: Pass
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- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Thickness | 1/8″, 3/16″, 1/4″, 3/8″, 1/2″, 3/4″, 1″ | — |
| Color | Charcoal Gray | — |
| Material/Substrate | Polyester Polyurethane Foam | — |
| Cell Structure | Open Cell | — |
| Density | 6 lb/ft³ ±10% | ASTM D3574 |
Mechanical Properties
| Property | Value | Test Method |
| Compression Force Deflection @ 25%, Average | 0.75 psi | ASTM D3574 |
| Compression Force Deflection @ 25%, Minimum | 0.65 psi | ASTM D3574 |
| Compression Force Deflection @ 50%, Average | 1.20 psi | ASTM D3574 |
| Compression Force Deflection @ 50%, Minimum | 0.95 psi | ASTM D3574 |
| Tensile Strength (Minimum) | 10 psi | ASTM D3574 |
| Tensile Strength (Average) | 18 psi | ASTM D3574 |
| Elongation (Minimum) | 150% | ASTM D3574 |
| Elongation (Average) | 190% | ASTM D3574 |
Flame & Fire Performance
| Property | Value | Test Method |
| Flame Retardant | Flame retardant by special request | — |
| FMVSS-302 | Pass | — |
| UL 94 HF-1 | Pass | — |
Regulatory / Compliance Data
| Property | Value | Test Method |
| REACH | Pass | — |
| RoHS | Pass | — |
Aging Performance
Dry Heat Aging
| Property | Value | Test Method |
| Retention of Tensile Strength After 22 Hours, 140°C, Dry Heat Aging | Min. 70% | ASTM D3574 |
Steam Autoclave
| Property | Value | Test Method |
| Retention of Tensile Strength After 3 Hours, 105°C, Steam Autoclave | Min. 70% | ASTM D3574 |
Compliance
- FMVSS-302 — Compliant
- UL 94 HF-1 — Compliant (at 0.12″ minimum thickness)
- REACH — Compliant
- RoHS — Compliant
- Acoustical and sound absorbing foam components in automotive, HVAC, and enclosure assemblies where the highest available density in the polyester polyurethane series is required
- Air dam foam and pads in automotive and electronic assemblies requiring the highest compression force deflection at 50% in the series
- Die-cut or clicked foam components for high-volume production where high-density polyester polyurethane substrate and firm compression response are specified
- Automotive interior and underhood acoustic insulation components requiring FMVSS-302 and UL 94 HF-1 compliance at 0.12″ minimum thickness
- Heavy-duty sound damping pads and baffles in industrial equipment and appliance assemblies where a high-density open cell foam is specified
Common industries: automotive, HVAC, acoustics, industrial equipment, electronics.
The 6# Polyester Polyurethane Foam is the highest-density grade in H-O Products’ polyester polyurethane foam series, at 6 lb/ft³ ±10%, and is described as a medium firm open cell foam. It is designed for acoustical sound absorption and air dam foam and pad applications where the highest available density and compression resistance in the series are required. The material can be easily die-cut into any shape and is clickable, supporting high-volume converted part production.
Tensile strength is 10 psi minimum and 18 psi average per ASTM D3574. Elongation is 150% minimum and 190% average. Compression force deflection at 50% is 1.20 psi average and 0.95 psi minimum — the highest 50% deflection resistance in the series. Retention of tensile strength after 22 hours at 140°C dry heat aging is a minimum of 70%, and after 3 hours at 105°C steam autoclave is a minimum of 70%, both per ASTM D3574.
The material passes FMVSS-302, UL 94 HF-1 (at 0.12″ minimum thickness), REACH, and RoHS. A flame retardant formulation is available by special request.
Compliant with FMVSS-302, UL 94 HF-1 (at 0.12″ minimum thickness), REACH, and RoHS.
What differentiates the 6# Polyester Polyurethane Foam from the lower-density 4# and 2# grades?
The 6# is the highest-density grade in the series at 6 lb/ft³ and delivers the highest compression force deflection at 50% — 1.20 psi average vs. 0.85 psi for both the 4# and 2# grades. This makes it the appropriate selection when the greatest resistance to compression at higher deflection levels is required. It also carries the highest minimum elongation in the series at 150%. The 6# and 4# share the same UL 94 HF-1 minimum thickness requirement of 0.12".
Why does compression force deflection matter for open cell polyurethane foam selection?
Compression force deflection (CFD) defines the load required to compress the foam to a given deflection level, which determines how much resistance the foam provides in a seal, cushioning, or air dam application. The 6# grade's CFD at 50% — 1.20 psi average — is significantly higher than both the 4# and 2# grades (0.85 psi each at 50%), making it the grade to specify when load-bearing and firm compression resistance at higher deflection levels are required.
What is the service temperature range for the 6# Polyester Polyurethane Foam?
A specific service temperature range is not stated on the manufacturer's TDS for this material. Aging performance data includes retention of tensile strength after 22 hours at 140°C dry heat aging and after 3 hours at 105°C steam autoclave, both with a minimum retention of 70%.
Is the 6# Polyester Polyurethane Foam suitable for regulated environments?
Yes. The material passes FMVSS-302, UL 94 HF-1 (at 0.12" minimum thickness), REACH, and RoHS, as stated on the TDS. A flame retardant formulation is also available by special request.
How should the 6# Polyester Polyurethane Foam be specified?
Specify grade (6# Polyester Polyurethane Foam), thickness, compliance requirements (FMVSS-302, UL 94 HF-1 minimum thickness if applicable, REACH, RoHS), dimensional tolerances, and finished format.
