14 сентября, 2015 
Malyar Silicone adhesives and sealants typically contain polymer, fillers, cross-linker, catalyst, and other additives. The most common fillers are the reinforcing fumed silicas or the less reinforcing grades of calcium carbonate. Other fillers and pigments, such as carbon black and titanium dioxide, are also used. Silicones are typically made in high shear, vertical change can mixers, but continuous processing equipment may also be employed. Processing details are generally held proprietary, but some general guidelines are in order.
Since most silicones cure through reaction with water, it is important that the moisture content of fillers and other additives be controlled. The moisture content of fumed silica, for example, can vary from 0.2 to over 2%, depending on the humidity conditions during storage. It is also critical that introduction of moist air be kept to a minimum during mixing. Air incorporated during processing must generally be removed to reduce the tendency toward cured gels and related appearance problems in the final product.
The dispersion of the filler particles is also important to final sealant appearance. With increasing costs of fillers, it is also important to optimize dispersion to maximize the rheological and reinforcement benefits provided by the fillers. Manufacturers must balance the mixing time and energy required for complete dispersion with resultant product appearance and physical properties.
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