Patent ID: 7368517

Claim:
A process for preparing crosslinked or branched organopolysilanes which comprise at least one unit of formulae 1 and 2 RSi═ (1), ═Si═ (2); at least one unit of the formula 3 R 2 Si═ (3); and optionally units of the formula 4 R 3 Si— (4) wherein at least one silane of the formulae 1a and/or 2a RSiX 3 (1a), SiX 4 (2a), at least one silane of the formula 3a R 2 SiX 2 (3a), and optionally one or more silanes of the general formula 4a R 3 SiX (4a) where R is hydrogen or a hydrocarbyl radical having from 1 to 18 carbon atoms and X is fluorine, chlorine or bromine, are reacted in a plurality of steps with an elemental alkali metal, the addition of the reactants 1(a) through 4(a) being such that the silane of the general formula 3a during its reaction with elemental metal in any given step contains at most 1 mol % of silane of the formulae 1a and 2a, and wherein at least two molar parts of total silanes of the formulas 1a and 2a are reacted per 100 parts of the silane of formula 3a.