Transparent Silicone Moulding Rubber 5kg Kit

(Inc. 20% VAT)
(£85.00 Exc. VAT)


Kit consists of 2.5kg of PART A and 2.5kg of PART B

Total kit volume 4.71 Litres

PART A and PART B are both clear liquids which are odourless and non-toxic. They react to form a flexible, elastic, transparent material with outstanding release properties, a high chemical resistance and a temperature resistance of 200°C. There is practically no shrinkage (0.08%) and excellent reproduction of fine detail. For optimal clarity try to keep mould walls to a maximum of 10mm thick. This rubber is suitable for casting a wide range of materials please see below for more details.


Available in three hardnesses; soft medium and firm. The soft is better suited to moulding delicate, fragile items where the rubber needs to be soft and flexible enough to peel off without damaging the casting. The medium is suitable for the majority of cases.

This product is not suitable for use with food. For a suitable product please click here

It may cause skin irritation making this product unsuitable for applying directly to human skin for life casting. For a suitable product please click here

The maximum operating temperature is 250°C. For a high temperature rubber click here

For creating a two part mould or moulding a glass object a release agent is required click here

Can be pigmented to a wide range of colours click here

It can be softened to your own requirements using this softening additive click here

Can be made thixotropic for applying to vertical surfaces or to over head objects click here


Properties Units Soft Medium Medium Slow Firm
Pot Life (25°C)   20-40 mins 20-40 mins 3-4 hours 20-40 mins
Cure Time (25°C) Hours 3-5 3-5 24 3-5
Viscosity (25°C) Mpa.s 6000 6000 4,500 6,200
Density (25°C) g/cm3 1.06 1.08 1.06 1.1
Hardness Shore A 10 20 20 40
Linear Shrinkage % 0.1 0.1 0.1 0.1
Tear Strength KN/m 10 14 14 23
Elongation at Break % 600 580 490 550
Tensile Strength Mpa 2.2 3.8 3.8 7


Polyurethane resin

Epoxy resin *
(* Excl. some epoxies, check with supplier of the resin if silicone moulds are suitable.)

Polyester resin

Acrylic resin

Plastisol (PVC)



Polymer clays



Metals with a pouring temperature below 250°C


A release agent will not create a sufficient barrier to prevent cure inhibition but a layer of paint will. If the paint is solvent based allow sufficient time for the solvent to completely evaporate off as that too can inhibit the cure

Great care must be taken when handling and mixing all addition-cured silicone elastomer systems. All the mixing tools (vessels and spatulas) should be clean and constructed in materials which do not interfere with the curing mechanism. The cure of the rubber can be inhibited by the presence of compounds of nitrogen, sulphur, phosphorus and arsenic; organotin catalysts and PVC stabilisers; epoxy resin catalysts and even contact with materials containing these substances e.g. moulding clays, sulphur vulcanised rubbers, condensation cure silicone rubbers, some printed plastics, onion and garlic.


pdf-image-white.jpg Technical Data Sheet pdf-image-white.jpg Safety Data Sheet Part A  pdf-image-white.jpg Safety Data Sheet Part B