| Category | Polymer , Thermoset | 
| Manufacturer | 3M | 
| Trade Name | |
| Port | Ningbo port,China | 
| Trade Terms | FOB, CFR, CIF | 
| Payment Terms | L/C, T/T, Western Union | 
| Download PDF | 3M AC-251 Black Class B-1 Aerospace Sealant.pdf  | 
| Price | EMAIL US sales@lookpolymers.com | 
| Physical Properties | Metric | English | Comments | 
|---|---|---|---|
| Density | 1.59 g/cc | 0.0574 lb/in³ | cured 14 days @ 50% RH; AMS-S-8802 | 
| Volatiles | 2.0 % | 2.0 % | |
| Brookfield Viscosity | 900000 - 1.60e+6 cP | 900000 - 1.60e+6 cP | Base, RVF #7 sp @ 2 rpm | 
| Mechanical Properties | Metric | English | Comments | 
|---|---|---|---|
| Hardness, Shore A | 55 | 55 | cured 14 days @ 50% RH; AMS-S-8802 | 
| Tensile Strength at Break | 2.14           MPa @Temperature 121 °C, Time 605000 sec | 310           psi @Temperature 250 °F, Time 168 hour | |
| 2.41           MPa @Time 1.21e+6 sec | 350           psi @Time 336 hour | Standard Cure | |
| Elongation at Break | 300 % @Temperature 121 °C, Time 605000 sec | 300 % @Temperature 250 °F, Time 168 hour | |
| 370 % @Time 1.21e+6 sec | 370 % @Time 336 hour | Standard Cure | 
| Thermal Properties | Metric | English | Comments | 
|---|---|---|---|
| Maximum Service Temperature, Air | 121 °C | 250 °F | AMS-S-8802, cured 14 days @ 50% RH | 
| 182 °C | 360 °F | AMS-S-8802, cured 14 days @ 50% RH | |
| Minimum Service Temperature, Air | -54.0 °C | -65.2 °F | AMS-S-8802, cured 14 days @ 50% RH | 
| Processing Properties | Metric | English | Comments | 
|---|---|---|---|
| Cure Time | 300 min | 5.00 hour | Tack-Free Time | 
| 420 min | 7.00 hour | ||
| Shelf Life | 9.00           Month @Temperature <=26.7 °C | 9.00           Month @Temperature <=80.1 °F | 
| Descriptive Properties | Value | Comments | 
|---|---|---|
| Appearance | Black | |
| Black | Base | |
| Black | Accelerator |