Application: Inhibitors MVC and DVS are pure silicone-based inhibitors which control the activity of the Pt-catalyst. They are used when exceptionally long working times or very low dosage levels are required. The typical dosage is between 0.01 and 1 %. Inhibitors 200 – 600 are ready-to-use mixtures of various alkinol or silicone based inhibitors in Polymer VS. Depending on the required pot life, the dosage is typically between 1 and 10 %. The below diagram shows the effect of the various inhibitor solutions in a two component addition-cure silicone formulation. It shows the required inhibitor concentration to get a working time of 40 minutes. Another important parameter is the volatility of the inhibitor. A high volatility is preferred e. g. in heat cure coatings. Here, a fast evaporation leads to a quick full cure at the moment of heating. However, in such formulations working time can shorten during open storage of the components. Low volatile inhibitors are typically used when vulcanization shrinkage and VOC are to be minimized.

Information provided by Evonik