Abstract: Silylated silica is prepared by silylating silica with an organosiloxane composed of A units of the formula (I) (R13SiO1/2)??(I) and B units of the formulae (IIa-c) (R12SiO2/2), and/or??(IIa) (R1SiO3/2), and/or??(IIb) (SiO4/2)??(IIc), optionally having 1 or 2 attached groups —X on Si atoms, where X is OR, R being hydrogen or a monovalent alkyl radical having 1-4 carbon atoms, halogen, or acetoxy, R1 is a saturated or unsaturated, monovalent, optionally halogenated C1-18 hydrocarbon radical the groups ?SiX or ?SiX2 optionally present in a number C, wherein A, B, and C satisfy the relationships: 1?B?100 or 750<B<10 000, B?A+C, and, when A+C=0, 10?B?100 or 750<B<10 000. The silylated silica has a particularly homogenous coating of silylating agent.

Abstract: Silylated silica is prepared by silylating silica with an organosiloxane composed of A units of the formula (I)

Abstract: The invention relates to crosslinkable materials based on organopolysiloxanes. Said materials are characterized in that in addition to organopolysiloxanes they contain at least one low-molecular organosilicon compound with 2 to 17 silicon atoms comprising units of the formula (I) R1aR2b(OR3)cSiO4−(a+b+c)/2, R1, R2, R3, a, b and c having the meaning given in claim 1 provided that low-molecular organosilicon compounds comprising units of the formula (I) where b is 0 have at least one unit of the formula (I) in which a is 0 or 1, and at least one unit of the formula (I) in which a is 3.

Abstract: The invention relates to a process for the silylation of very finely divided inorganic oxides, in which the very finely divided inorganic oxides are treated with at least one silylating agent which is relatively nonvolatile in the temperature range of the overall process, with the proviso that the relatively nonvolatile silylating agent is admixed with the very finely divided inorganic oxides as a liquid, in the form of a very finely atomized aerosol. Furthermore, the invention relates to a highly apolar, pyrogenic silica prepared by this process.

Abstract: The invention relates to a process for the silylation of very finely divided inorganic oxides, in which the very finely divided inorganic oxides are treated with at least one silylating agent which is relatively nonvolatile in the temperature range of the overall process, with the proviso that the relatively nonvolatile silylating agent is admixed with the very finely divided inorganic oxides as a liquid, in the form of a very finely atomized aerosol. Furthermore, the invention relates to a highly apolar, pyrogenic silica prepared by this process.