PlatSil® 73-25 Silicone Rubber

platsil-73-25PlatSil® 73-25 is a 1A:1B mix, platinum silicone rubber that cures to a soft/mid-range hardness of A25. This silicone is a blend of all the best properties available for a silicone mold rubber. A 15-minute pour time coupled with a 4-5 hour demold time is the best of both worlds!

This low-viscosity mix (6,000 cP) often does not require vacuum degassing (PlatSil 73-15 & 73-20 also do not necessarily require vacuum degassing). 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!

This liquid rubber is great for making molds for all types of resin casting (polyurethane, polyester, epoxy) and foam casting and does not require application of release agent prior to casting. It is often used for prototyping, model making, hobby reproduction, taxidermy, soap and candle making, and much more.

Pour as supplied or thicken for brush-on molds using PlatThix liquid thickener.


Mix Ratio Shore Hardness Pour Time Cured Color Mixed Viscosity Specific Volume Demold Time
1A:1B A25 15 min. Green 6,000 cP 24.3 in³/lb 4 – 5 hr.
Accessories: PlatThix Liquid ThickenerPlatSil® 71/73 Part R RetarderSilicone Fluid 50csPlatSil® 71/73 Part X Accelerator


Product Literature: Technical Bulletin | Safety Data Sheets | Physical Properties Bulletin | Sealer & Release Agent Selection Guide

Video Tutorials: How to Make Silicone Molds for Casting Wax Candles using PlatSil 73-25

Blog Tutorial: Two-Piece PlatSil® 73-25 Mold of a Small Bust


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