Silicones, Inc.Silicones, Inc.RTV-2 Silicone Rubber
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Cure Chemistry · Addition Cure

Platinum Cured Silicone Rubber

Addition-cure RTV-2 systems crosslink with a platinum catalyst. The result is near-zero shrinkage, high dimensional accuracy, and molds that keep their detail for years.

How it cures

Platinum cure silicone uses a platinum catalyst to link the base polymer and crosslinker directly. The reaction produces no byproducts, so the rubber cures with near-zero shrinkage and holds tight dimensional tolerances.

Because nothing evaporates during cure, platinum systems capture fine detail and keep it over the life of the mold. Heat accelerates the cure when faster demolding matters.

The trade-off is sensitivity. Sulfur-containing clays, tin-cure residues, and some 3D-printed surfaces can inhibit the cure and leave tacky spots. Clean tools and a small test patch are standard practice.

Strengths and trade-offs

Shrinkage
Near zero
Dimensional accuracy
High
Cure byproduct
None
Relative cost
Higher
Inhibition sensitivity
Sulfur and tin residues
Mold life
Long library life

Best for

  • Precision molds with tight tolerances
  • Long-life production and library molds
  • Applications where cure purity matters
  • Heat-accelerated production work

General guidance. Confirm fit with our team for your application.

Choosing between the two

Casting against unpredictable or previously used surfaces, or optimizing for cost? Tin cure is the forgiving general-purpose choice.

Platinum cure products

SKUProductCureShore A (7 day)Mixed viscosity (cps)SDSBuy online
P-10Very-low-durometer platinum-cure RTV-2 mold making siliconePlatinum125,000–15,000SDSPDF
P-125Transparent medium-durometer platinum-cure RTV-2 mold making siliconePlatinum4090,000–110,000SDSPDFBuy onlinefrom $37.00
P-15Low-durometer platinum-cure RTV-2 mold making siliconePlatinum183,000–13,000SDSPDF
P-157Soft platinum-cure RTV-2 silicone gel for special effectsPlatinumn.a.5,000–7,000SDSPDF
P-17Low-viscosity platinum-cure RTV-2 potting and encapsulation siliconePlatinum5015,000–25,000SDSPDF
P-20Low-durometer high-tear platinum-cure RTV-2 mold making siliconePlatinum2215,000–25,000SDSPDF
P-288High-durometer platinum-cure RTV-2 silicone for prototyping and foam castingPlatinum5570,000–89,995SDSPDF
P-378Flame-retardant platinum-cure RTV-2 potting and encapsulation siliconePlatinum707,500–8,500SDSPDF
P-429Transparent platinum-cure RTV-2 silicone gel for potting and encapsulationPlatinumn.a.7,000–7,000SDSPDF
P-44P-44 Silicone for mold making. Two catalysts available, P-44 A-1 for increased release, A-2 for dry release.Platinum4550,000–60,000
P-45Medium-durometer fast-cure platinum-cure RTV-2 mold making siliconePlatinum4565,000–85,000SDSPDF
P-50Firm-durometer platinum-cure RTV-2 silicone for prototyping and foam castingPlatinum5470,000–90,000SDSPDF
P-537Ultra-soft platinum-cure RTV-2 silicone for animatronicsPlatinum111,000–12,000SDSPDF
P-541Fast-cure platinum-cure RTV-2 silicone for body moldingPlatinum3065,000–7,000SDSPDFBuy onlinefrom $35.00
P-565P-565 Silicone RubberPlatinum164,000–8,000Buy onlinefrom $37.00
P-573Ultra-soft platinum-cure RTV-2 silicone for animatronicsPlatinum440,000–41,000SDSPDF
P-574Soft platinum-cure RTV-2 silicone gel for special effectsPlatinumn.a.9,000–9,500SDSPDF
P-592Translucent medium-durometer platinum-cure RTV-2 mold making siliconePlatinum5840,000–60,000SDSPDF
P-60Firm-durometer platinum-cure RTV-2 silicone for prototyping and foam castingPlatinum6295,000–120,000SDSPDF
P-614Fast-demold firm-durometer platinum-cure RTV-2 mold making siliconePlatinum6035,000–45,000SDSPDF
P-65High-durometer platinum-cure RTV-2 silicone for trapped rubber moldingPlatinum7164,000–68,000SDSPDF
P-656Soft 1:1 platinum-cure RTV-2 silicone for special effects and glove moldsPlatinum915,000–15,000SDSPDF
P-697Medium-durometer fast-cure platinum-cure RTV-2 mold making siliconePlatinum4345,000–75,000SDSPDF
P-70High-durometer platinum-cure RTV-2 silicone for trapped rubber moldingPlatinum7060,000–70,000SDSPDF
P-727Low-durometer 1:1 platinum-cure RTV-2 silicone for glove molds and animatronicsPlatinum912,000–18,000SDS2 files
P-750Fast-cure platinum-cure RTV-2 silicone for reusable vacuum bagsPlatinum2620,000–21,000SDSPDF
P-824P-824 reusable vacuum bagging RTV-2 siliconePlatinum2517,000–23,000SDSPDF
P-829Soft platinum-cure RTV-2 silicone for animatronics and prostheticsPlatinum515,000–16,000SDSPDF
P-831Transparent platinum-cure RTV-2 silicone gel for potting and encapsulationPlatinumn.a.n.a.
P-832Thixotropic platinum-cure RTV-2 silicone gel for potting and encapsulationPlatinumn.a.n.a.
P-90High-tear platinum-cure RTV-2 mold making siliconePlatinum3540,000–55,000SDSPDFBuy onlinefrom $36.00

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