Monomeric silanes, production

Additional CaSi reactions were carried out with halogens, PC15, and other halogenating agents. In all cases a decomposition of the silicon chains to monomeric silane derivatives occurred before reaction of the calcium was complete, so no definable products could be obtained. 

Nevertheless, with regard to filler treatment and limestone impregnation, it is still considered difficult to coat calcium carbonate with silicone. As shown in Table 1, the commercial monomeric silanes that are used for coating the surfaces of fillers nowadays are not effective for coating calcite [19, 20, 21]. The idea that the production of a silicone-coated surface is difficult may result from the misconception that attachment of high silicone polymers to calcium carbonate is equally problematic. The issue of attachment of silicone to the mineral surfaces has still not been finally resolved [62]. 

Silicone nanospheres with different particle diameters, crosslinking density, and chemical functionalization are accessible by aqueous hydrolysis-condensation sequences of silane and siloxane precursors [1-3] and subsequent isolation. Grafting of functionalized particles with organopolymers [1] or surface modification [2] results in nanosized silicone domains which are readily dispersible in monomeric and polymeric systems. A variety of these versatile, tailor-made products will soon be launched by Wacker on a commercial scale. 

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