US Patent 7396894 Process for preparing linear organopolysiloxanes having Si-H groups

The invention provides a process for preparing linear organopolysiloxanes (P) having diorganosiloxy units and Si—H groups, in which, in a first step, diorganodichlorosilanes (A) and monochlorosilanes (B) and optionally dichlorosilanes (C), at least one of the monochlorosilanes (B) or dichlorosilanes (C) containing Si—H groups, are reacted with at most 0.5 mol of water per mole of hydrolyzable chlorine to give a partial hydrolyzate (T) and gaseous hydrogen chloride, and, in a second step, the SiCl groups still present in the partial hydrolyzate (T) are removed by treating with water to form hydrochloric acid, and a hydrolyzate (H) containing the organopolysiloxanes (P) is obtained.