RTV 440 - Translucent high strength mould making silicone.
 
2 component, low viscosity platinum curing silicone compound.
Mix ratio by weight = 1:1 (100 grams Part A : 100 grams Part B).
Available as: 1.0Kg, 2.0Kg, 10.0Kg, 20.0Kg, & 40.0Kg kits.
Standard curing agent.
 
Main features
Has exceptionally low viscosity, making it easy to de-gas
     and pour, minimising the air content when fully cured.
High resistance to initial tearing and tear propagation
Can be made thixotropic with BS4 Thixo.
Mixing ratio = 1:1
 
Applications
RIM Moulding
Vacuum Casting
General pattern & model mould making
Production of high quality finished parts
Jewellery moulds
 
 
Viscosity @25°C (mPa·s): Part A 8,200, Part B 4,500
Pot life mixed (1000g): 50 minutes
Mixed viscosity(mPa·s): 6,200
Curing time: 12 hours
 
Cured Elastomer (>24 hours @ room temp.)
Colour: translucent
Hardness Shore A:  37-38
Tensile strength (MPa):  6
Elongation at tear (%):  350
Resistance to tear propagation (N/mm): >10
 
Thixotropic adjustment
By the addition of our 'BS4 Thixo' Thixotropic Agent, the silicone rubber con be made thixotropic for special applications, i. e. the compound is then no longer liquid and castable, but pasty, brushable. For this, add approx. 0.5 - 1.0 % of Thixotropic Agent to the mixed components RTV 440 Part A & RTV 440 Part B.
The thixotropic effect will already set in after a short while.

When RTV 440 is used as mould making material (production of negatives), there is no release agent required for de-moulding.
For the production of multipart moulds and to avoid the adhesion of RTV 440 to itself, use the surface of the part already vulcanized with a release agent, then cast the second part of the mould.
We recommend our Release Agents.