HN-640 A/B is an industrial-grade, two-component RTV2 tin cure (condensation cure) liquid silicone rubber, mixed at 100:2 and vulcanized at room temperature. With an easy-foaming, high-fluidity formulation, high tear resistance and low shrinkage, it is a cost-effective choice for gypsum craft molds, construction molds and general industrial mold making, supplied in bulk for factory production runs.
| Property | Value |
|---|---|
| Model | HN-640 A/B |
| Mixing Ratio (A:B) | 100:2 |
| Viscosity | 170,000 cps |
| Density | 1.06 g/cm³ |
| Hardness | 20 Shore A |
| Tensile Strength | 3.1–3.6 MPa |
| Tear Strength | 19.8–24.3 kN/m |
| Elongation | 600–720% |
| Linear Shrinkage | ≤0.2% (≤2‰) |
| Curing Agent Addition | 2–3% |
| Operating Time | 30–40 minutes |
| Curing Time | 3–4 hours at room temperature |