Chemistry of the silylamines. II. The condensation of silylamines with silanediols

The condensation of mono‐ and difunctional silylamines with (C 6 H 5 ) 2 Si(OH) 2 , (C 2 H 5 ) 2 Si(OH) 2 , HO[Si(C 6 H 5 ) 2 O] 2 H, HO[Si(CH 3 ) 2 O] 3 H, and a 1530 mol. wt. hydroxy endblocked dimethylsilicone fluid was investigated. The structure of the reacting species, the addition of acid catalyst, temperature, and solvent were shown to have a marked effect on the reaction rate. The rate of reaction of silylamines toward a given silanediol decreased in the order The information obtained from the condensation of hexamethyltrisiloxane‐1,5‐diol and N , N ‐diethylaminotrimethylsilane demonstrated that self‐condensation of the silanediol did not occur to any extent under the reaction conditions employed. This condensation reaction offers a unique approach to the synthesis of silicone polymers and copolymers allows control of the location of crosslinking sites in the silicone polymer chain, and affords a method for the preparation of silicone block copolymers.