Silicone Thinning Fluid Additive
Silicone Thinning Fulid is a dilutant that is clear, odorless, and has a low Viscosity which was especially designed to reduce the viscosity properties of RTV and Platinum cure silicone's. It is essentially non-toxic, non-irritating, and non-sensitizing. It has a workable temperature range of -40°F to 550°F, and is heat and age stable. It can survive indefinite exposure at temperatures up to 149°C. Because of the extremely low surface tension of this fluid, it aids the flow of silicone compounds.
Normally, this thinner is added at a 5% level based on the weight of Silicone base being used. At this level, no loss of physical property can be observed. Incidentally, the amount of Silicone catalyst is also based on the amount of Silicone base being used and does not have to be increased because of the thinner being added. An example of a proper batch would be 10 + 1 + 1, which is 10 oz of Silicone base + 1 oz of catalyst + 1 oz of diluent. The room temperature viscosity of this silicone oil is 50 centistokes (cSt).
This thinner, when added, alters the properties of Silicone in the following manner:
(1) Reduced Viscosity. Silicone's with 10% thinner will show a much lower viscosity, and air release properties will be enhanced. Flowability will also be noticeably improved. This insures that the Silicone will get into the detail better.
(2) Increased Chemical Resistance. In some applications, the presence of Silicone diluent improves the resistance to chemical attack and thus extends mold life. In fact, some firms make it a practice to wipe additional thinner onto the face of the mold periodically to bolster the release and the life of the mold.
(3) Lower Durometer. In concentrations above 10%, the thinner will begin to plasticize the Silicone to produce a cured product that is softer than usual.
(4) Lower Tear Strength. Again, in concentrations above 10%, the thinner will begin to lower the tear strength and the tensile strength, while elongation is increased.