Smooth-Cast™ 321
- Chemical Family
- Polyurethanes (PU)Urethanes
Smooth-Cast™ 321 consists of ultra-low viscosity casting resins that yield virtually bubble-free off-white castings. The Smooth-Cast™ 320 resins are sister products to our popular Smooth-Cast™ 300 Series of bright white plastics, but are easier to color using SO-Strong™, UVO™ or Ignite™ color tints. Smooth-Cast™ 320 series is easy to mix and pour, offering the convenience of a 1A:1B by volume or 100A : 90B by weight mix ratio.
Product families
- Polyurethanes
Other characteristics
- Brand
- Smooth-Cast
- Density
- 1050.0 - 1050.0 kg/m³
- End Uses
Body Implants, Dental Applications, Jewelry, Modeling Material, Prototyping
- Polymer Name
- Polyurethane (unspecified)
- Tensile Strength
- 20.67 - 20.67 MPa
- Processing Methods
- Casting
- Safety
Wear safety glasses, long sleeves and rubber gloves to minimize contamination risk. Use only in a well-ventilated area.
- Markets
- Consumer Goods
- Healthcare & Pharma
- Industrial
- Shelf LIfe
Shelf life of product is reduced after opening. Remaining product should be used as soon as possible. Immediately replacing the lids on both containers after dispensing product will help prolong the shelf life of the unused product. XTEND-IT™ Dry Gas Blanket (available from Smooth-On) will significantly prolong the shelf life of unused liquid urethane products.
- Technology
- Plastics
- Material Features
- Durable
- Good Toughness
- Low Viscosity
- Machinable
- Moisture Resistant
- Paintable
- Solvent Resistant
- Prodcut Highlights
The Smooth-Cast™ 320 Series resins readily accept pigments and fillers (such as URE-FIL™ 3, 5 and 7 from Smooth-On). Fully cured castings are tough, durable, machinable and paintable. They resist moisture and mild solvents. Applications for Smooth-Cast™ 320 Series resins include reproducing small to medium size sculptures, making prototype models, special effect props, decorative jewelry and taxidermy (bones, antlers, teeth etc.).
Technical data
Table 1 of 1
16 rows| Characteristic | Value | Unit | Method |
|---|---|---|---|
| Pot Life at 73°F (23°C) | 7-9 | Minute | ASTM D-2471 |
| Cure Time at 73°F (23°C) | 30 | Minute | — |
| Tensile Strength | 3000 | psi | ASTM D-638 |
| Tensile Modulus | 138000 | psi | ASTM D-638 |
| Elongation at Break | 8 | % | ASTM D-638 |
| Flexural Strength | 3500 | psi | ASTM D-790 |
| Flexural Modulus | 110000 | psi | ASTM D-790 |
| Compressive Strength | 3550 | psi | ASTM D-695 |
| Compressive Modulus | 40300 | psi | ASTM D-695 |
| Shrinkage | 0.007 | in./in. | ASTM D-2566 |
| Mix Ratio | 1A:1B (100A:90B) | by volume (by weight) | — |
| Mixed Viscosity | 80 | cps | ASTM D-2393 |
