The PMC®-121 Series urethane rubbers feature convenient one-to-one by volume mix ratios. PMC®-121/30 Dry and PMC®-121/30 Wet are exceptionally strong and abrasion resistant for soft urethane mold rubbers. These rubbers will meet the stringent demands of production casting of wax, plasters, concrete, resins and epoxies. Vibrant colors can be achieved by adding So-Strong® Color Tints, available from Smooth-On. The dry version does not exude an oil and can be used for casting waxes, Smooth-On liquid plastics, gypsum plasters and other materials. The wet version contains a built-in release agent to aid in demolding hard plasters and concrete.


Product Name: A:B Mix Ratio Demold Time Elongation at Break Mixed Viscosity Pot Life Shore A Hardness Tear Strength Weight: CU.IN./LB
PMC® -121-30 Wet or Dry 1:1 by volume 16 hours 1000% 1800 cps 30 min. 30 55 pli 27.7
PMC®-870 2:1 by weight 16 hours 600% 3000 cps 35 min. 70 160 pli 27.2
PMC® -780 Dry or Wet 2:1 by weight or volume 48 hours 700% 2000 cps 25 min. 80 200 pli 27.2
PMC® -790 2:1 by weight or volume 48 hours 600% 3000 cps 20 min. 90 300 pli 25.9