Processes for preparing siloxane-modified polyisocyanates, the processes comprising: providing a polyisocyanate reactant; and reacting the polyisocyanate reactant with a hydroxyl-containing siloxane having a number-average molecular weight of 200 to 3000 g/mol and an average OH functionality of greater than or equal to 1.8, and corresponding to the general formula (I): wherein X represents an aliphatic, unbranched or branched C1 to C20 radical optionally containing ether groups; R represents a hydroxyl-functional radical; R1 represents a hydrogen or an optionally heteroatom-containing C1 to C20 hydrocarbon radical; and n is 1 to 40; siloxane-modified polyisocyanates prepared thereby, and uses therefor.