摘要 |
A room temperature vulcanizable silica-containing silicone rubber can be produced without pretreatment of the silica by mixing specified amounts of (A) A LINEAR ORGANOPOLYSILOXANE OF THE FORMULA <IMAGE> (b) silica of a specific surface area of at least about 50 m2/g in the presence of water and a modifying agent of the formula (R3Si)nX, then adding <IMAGE> c) <IMAGE> d) and (E) ANOTHER FILLER OR PIGMENT, THIS CONSTITUTING A FIRST COMPONENT WHICH IS MIXED WITH A SECOND COMPONENT WHICH COMPRISES (F) A SILICIC ACID ESTER OF THE FORMULA (RO)3SiR' (g) a heavy metal catalyst, and (H) A MONOHYDRIC ALIPHATIC ALCOHOL OF THE FORMULA R-(CH2)a-OH Even though the silica is not pretreated as was heretofore necessary, the mixtures exhibit good flow properties and the rubber is characterized by improved mechanical properties. |