RTV-2 Silicone Rubber for Molds
SuperSil Materials Co., Ltd. manufactures a full range of two-part, room-temperature curing silicone rubbers that offer great flexibility, tear strength, chemical resistance, and release properties. Silicone molds can be used to cast a variety of materials, including polyurethane, polyester and epoxy resins, polyurethane foam, plaster, wax, concrete, low melting metals, and more.
SuperSil Materials Co., Ltd. manufactures two different types of silicone rubbers: tin-cured (Supersil T-series) silicones and platinum-cured (Supersil P-series) silicones.
SuperSil™ Tin-cured Silicone mold rubber is a two-component material consisting of Base which when mixed with a Curing Agent, cures at room temperature by a condensation reaction.
SuperSil™ Tin-cured Silicone mold rubber is a general purpose RTV silicone elastomer which exhibits excellent tear strength, long library life, and accurate detail reproduction. It is used to make rubber molds that can be used to cast polyurethanes, epoxy’s, polyester’s, cement, concrete, soap, wax, plaster, etc.. It is easy to mix and de-air, and will cure at room temperature over virtually any surface.
Platinum-cured silicone (also known as addition-cure silicone), room temperature-curing silicones that cure to flexible, high-strength rubbers. SuperSil™ Platinum cured molds offer excellent release properties and release agent is not necessary when casting most materials. Compared to tin-cured silicone rubbers, platinum cured silicones exhibit long library life and non-shrinkage on cure.
A Comparison: Tin-cured silicone vs. Platinum-cured Silicone Mold Rubbers
- Supersil T-series silicones are condensation-cure systems that shrink slightly on cure (~0.5%) compared to addition-cure silicones Supersil P-series , which do not shrink on cure.
- Tin-cured silicones have shorter library life (2 to 5 years total) compared to platinum-cured silicones.
- Tin-cured silicones are slightly less expensive than platinum-cured silicones.
- Liquid platinum-cured silicones are more sensitive to certain materials (e.g., sulfur, tin compounds, Bondo) and suffer from cure inhibition (uncured surface material) more often than tin-cured silicones. (Supersil T-series)
- Cured tin silicone molds can inhibit some casting materials, including Platinum cure silicones, and many polyurethane rubbers.
- Platinum-cured silicones are skin safe, non-toxic, food-grade silicone.
Mold Making Materials COMPARISON
Tin cure silicone VS. Platinum cure silicone
Type | Advantages | Disadvantages | Casting materials |
|---|---|---|---|
| Tin-Cured Silicone | High strength, Cost-effective | Shrinks on cure (~0.3%), Cured rubber has limited storage life, Not food-grade | Most materials, especially resins, foams, plaster, wax, concrete etc. |
| Platinum-Cured Silicone | No shrink on cure, Cured rubber has long storage life, Excellent chemical resistance, Food-grade skin safe, 1:1 simple mix | Cure inhibited by some materials, a slight expensive than tin cure silicone | Most materials, especially resins, foams, plaster, wax, concrete etc. and some low-melt metals and food grade products mould. |
