Platinum Based Silicone
PlatSil Gel-OO & PlatSil Gel-10
PlatSil Gel-OO & PlatSil Gel-10
Polytek's PlatSil Gel product line consists of two 1A:1B platinum silicone rubbers with a 5-6 minute working time that cure in 30 minutes to a Shore A~10 hardness (PlatSil Gel-10) or a much softer Shore OO hardness of 30 (PlatSil Gel-OO). Use PlatSil Gels to create prosthetic appliances, skins, for lifecasting as well as for general RTV silicone mold making.

An array of accessory products can be used independently or in concert to increase working time, accelerate cure time, thicken the mix for brushing/layering, thin the mix for easier pouring, or "deaden" the rubber to soften and eliminate the snappy, synthetic look and feel of ordinary silicone rubbers. Deadened PlatSil Gels can be made to look, feel and move like all types of living tissue. Unlike silicone fluid, Smith's Theatrical Prosthetic Deadener does not leach from the cured rubber/appliance, so bonding and use are far simpler.

Both PlatSil Gel-10 and PlatSil Gel-OO share all the same array of accessory additives (including Smith's Deadener) making it easy to use either system. In fact, PlatSil Gel-10 an Gel-OO can be combined in any ratio (keeping their individual A's and B's 1:1) to make any hardness silicone gel between a Shore A~10 and a OO~30.

  • Shore A~10 or Shore~OO , translucent silicone rubber
  • Mix Gel-10 and Gel-OO together for variable hardness
  • Low viscosity mixes
  • Add "Deadener" to create ultra-realistic prosthetic appliances
  • Appliances are self-sticking, reuseable
  • Fast 30-minute cure
  • Color with SiliColor pigments
  • Thicken for layering/brushing
  • Speed or slow cure with additives
PlatSil 71 Series Silicone Rubber
PlatSil 71 Series mold rubbers are two-component, addition-cure, platinum catalyzed, high tear strength, flexible mold compounds. They have tough knotty tear strength which make them especially valuable to the mold making industry. They are recommended as mold material for polyester, epoxy, polyurethane resins, waxes and many other materials. PlatSil silicones are preferred because on curing, they do not shrink, they do not produce alcohol like tin-catalyzed silicones which can inhibit urethane castings, and they can be heat accelerated to speed the cure.

71-10   Demold Time: 30 minutes
Mix Ratio: 10A to 100B Shore A Hardness: 10 Pour Time: 5 min
Color: Pink Viscosity: 3,500 cP 26 in³ / lb
71-11   Demold Time: 4 hours
Mix Ratio: 1A to 1B Shore A Hardness: 11 Pour Time: 15 min
Color: Blue Viscosity: 15,000 cP 24.7 in³ / lb
71-20   Demold Time: 4 hours
Mix Ratio: 1A to 1B Shore A Hardness: 20 Pour Time: 25 min
Color: Light Purple Viscosity: 26,000 cP 24.7 in³ / lb

PlatSil 71-10 is a unique, fast-curing, soft (A~10) platinum silicone mold rubber. Mixed 1A:10B, this super low viscosity (3500 cP) silicone has a 5 minute working time and a 30 minute demold. As with other PlatSil platinum rubbers, 71-10 is great for casting resins as well as waxes and most other castable media.

PlatSil 71-11 is a unique, fast-curing (4-hour demold), 1A:1B mix, soft (A~10) platinum silicone mold rubber. This easy to mix 1:1 system is fun, fast and high-performance. No scales needed.

PlatSil 71-20 is a unique, fast-curing (4-hour demold), 1A:1B mix, mid range hardness (A~20) platinum silicone mold rubber. This easy to mix 1:1 system is fun, fast and high-performance. No scales needed.

71-30, 71-40, 73-45 and other products are available. Please call for details.
Platsil 73 Series
Platsil 73 Series
These addition-cure silicone mold rubbers are soft to mid-range hardness, high-performance, room temperature curing (RTV) systems offering excellent flexibility and toughness allowing durable molds to be made from relatively simple to the most highly detailed, undercut and complex models.

  • Shore A~30 to A~60 hardness liquid mold rubbers
  • High-strength, long mold life formulas
  • Excellent chemical resistance
  • No shrinkage upon cure
  • Reproduces finest detail over and over
  • Can be accelerated for rapid cure
  • Ideal for the most demanding resin casting applications
73-15   Demold Time: 4-5 hours
Mix Ratio: 1A to 1B Shore A Hardness: 15 Pour Time: 20 min
Color: White Viscosity: 2,500 cP 25 in³ / lb
73-25   Demold Time: 4-5 hours
Mix Ratio: 1A to 1B Shore A Hardness: 25 Pour Time: 15 min
Color: Green Viscosity: 6,000 cP 24.3 in³ / lb
73-45   Demold Time: 16 hours
Mix Ratio: 1A to 10B Shore A Hardness: 45 Pour Time: 60 min
Color: Green Viscosity: 35,000 cP 21.3 in³ / lb

PlatSil 73-15 is a super (we mean super) low viscosity (2500 cP) platinum silicone mold rubber that is clear/translucent and offers an easy, 1:1 mix ratio. It is a Shore A~15 hardness, making it quite soft and flexible for the most itricate and delicate mold making requirements. Since it is a platinum silicone mold rubber, it does not shrink on cure and should be tested for cure inhibition against any surface before a project is undertaken. PlatSil 73-15 has a 15 minute working time and is able to be demolded in 4-5 hours at ~75F/25C.

PlatSil 73-25 is a 1:1 mix platinum/addition-cure silicone that cures to a soft/mid-range hardness of A~25. This silicone is a blend of all the best properties available for a silicone mold rubber. PlatSil 73-25 is 1A:1B, by volume, so no scale is needed. The yellow colored Part A and green colored Part B make it easy to see when mixing is complete. A uniform, light, lime-green color means you're good to go! A mixed viscosity of 6,000 cP is easy to mix and pour and insures vacuum degassing is unnecessary. A 15 minute pour time coupled with a 4-5 hour demold time is the best of both worlds! PlatSil 73-25 does not shrink on cure and the resulting mold has great tear strength and easy release from all casting media.

PlatSil 73-45 is a 1A:10B mix, mid range hardness (A~45), low viscosity, platinum silicone mold rubber. Great for making molds for all types of resin casting (polyurethane, polyester, epoxy) and foams without release agents. Used for prototyping, model making, high density polyurethane foam casting, and much more. Long mold life, high-performance, great chemical resistance and no shrinkage on cure. A very popular rubber for casting foam architectural millwork, pots, plaques and other foam decor items. Pour as supplied or thicken for brush-on molds using PlatThix liquid thickener.
PlatSil 71 & 73 X Accelerator
This accelerator is used in all PlatSil silicone mold rubbers to speed the cure. Use of this product not only reduces the demold time, but also reduces working time. When added to the part B first, a ~1% addition (to the total B weight) decreases gel time to ~1/3 the normal. The addition of 2 parts decreases gel time to ~1/4 that of the normal for that PlatSil product. Experimentation required.
1 lb  
4 oz  
PlatSil 71 & 73 R Retarder
PlatSil 71 & 73 R can be used with all PlatSil silicone liquid rubbers to slow the cure and yield a longer working time. Adding ~1% (to the Part A first) of part R to the total A+B mixed weight roughly doubles the working time. Adding ~2% roughly triples the working time. Do not exceed 4%.
1 lb  
4 oz  
PlatThix - PlatSil Thickener
For thickening PlatSil 71, 73 and Gel-10 Series products to create a consistency useful for making brushed molds or for layering in the case of PlatSil Gel-10 skins or appliances. When brushing layers with faster curing PlatSil systems, make sure the subsequent layer is applied within 25 minutes of the previous coat in the case of PlatSil Gel-10 and within 1 hour in the case of PlatSil 71-11 and 71-20.
1 lb  
4 oz