of the above described silane compound and the disilazane compound in combination these two types of compounds may be added either separately or as a mixture prepared in advance the neutralization reaction can proceed even at room temperature but it is preferable to agitate the mixture at an elevated temperature of for example 40 u00b0 to 100 u00b0 c so that the neutralization reaction is complete within several hours it is of course that the temperature should not be excessively high in order to prevent the silane compound and the disilazane compound from dissipation by vaporization at least the temperature should not be higher than the boiling points of the silane and disilazane compounds after completion of the neutralization reaction the byproduct salt precipitated in the organopolysiloxane is removed by filtration and the remaining amounts if any of the silane and disilazane compounds are distilled away together with the solvent if any and the low boiling fraction of the organopolysiloxane formed in the polymerization reaction it is optional that the organopolysiloxane as neutralized is diluted with an organic solvent when it has an excessively high consistency to cause difficulties in the filtration of the precipitates in the following examples are given to illustrate the inventive method and the effectiveness thereof in more detail a mixture of three types of organopolysiloxane oligomers composed of 114 7 g of decamethyl tetrasiloxane 38 2 g of a.