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Key Differences
| Product Type |
|
|
| Mixed Viscosity | 1,800 cps | 11,000 cps |
| Pot Life | 30 minutes | 3 minutes |
| Cure Time | 16 hours | 20 minutes |
| Shore A Hardness | 30 | 20 |
| Color | Clear Amber | Translucent Green |
| 100% Modulus | 82 psi | 47 psi |
Disclaimer
Although we do our best to ensure accuracy, Smooth-On offers no warranties, promises, and/or representations of any kind, either expressed or implied, as to the accuracy, completeness, or reliability of the information contained on this Compare Tool, nor suitability of the information contained herein to your particular circumstances. Smooth-On assumes no liability for losses or damages of whatever nature (direct, indirect, consequential or other) associated with your use, or inability to use, the Compare Tool, or from your use (or failure to use) the information contained herein. Other useful tools include product technical bulletins and our extensive FAQ section. You can also contact our technical support team.All Technical Data
| PMC™-121 30/DRY | EZ-Spray™ Silicone 20 | |
|---|---|---|
| Product Type |
|
|
| Mixed Viscosity | 1,800 cps | 11,000 cps |
| Mix Ratio By Volume | 1A:1B | 1A:1B |
| Mix Ratio By Weight | 1A:1B | — |
| Pot Life | 30 minutes | 3 minutes |
| Cure Time | 16 hours | 20 minutes |
| Shore A Hardness | 30 | 20 |
| Specific Gravity | 1.04 g/cc | 1.08 g/cc |
| Specific Volume | 26.7 cu. in./lb. | 25.6 cu. in./lb. |
| Color | Clear Amber | Translucent Green |
| Die B Tear Strength | — | 100 pli |
| Die C Tear Strength | 75 pli | — |
| Tensile Strength | 400 psi | 495 psi |
| Elongation @ Break | 1,000 % | 470 % |
| 100% Modulus | 82 psi | 47 psi |
| Shrinkage | < .001 in. / in. | <.001 in. / in. |
| Useful Temperature (min) | — | -65 °F |
| Useful Temperature (max) | — | 500 °F |
Product Description
PMC™-121 30/DRY
The PMC™-121 Series urethane rubbers feature convenient one-to-one by volume mix ratios. PMC™-121/30 Dry is exceptionally strong and abrasion resistant for soft urethane mold rubbers. It does not exude oil and can be used for casting waxes, Smooth-On liquid plastics, gypsum plasters and other materials.
EZ-Spray™ Silicone 20
EZ~Spray™ Silicone 20 is a sprayable silicone which cures quickly to soft rubbers with high elongation and tear strength. Liquid silicone is sprayed through the EZ~Spray™ Junior Cartridge System which is an economical alternative to expensive spray equipment. After a suitable thickness is attained, EZ~Spray™ Silicone 20 cures in about 20 minutes. EZ~Spray™ Silicone cures with negligible shrinkage to strong, durable silicone rubbers good for production casting of polyester, epoxy or urethane resins, gypsum, concrete and other materials.