Organocyclopolysiloxane and a room temperature curable composition containing same

摘要

The room temperature curable organopolysiloxane composition of the invention comprises a dimethylpolysiloxane terminated at both molecular chain ends with silanolic hydroxy groups, an organocyclopolysiloxane, typically a cyclotetrasiloxane, having 2 or more alkenyloxy groups such as isopropenyloxy groups in a molecule as a crosslinking agent for the dimethylpolysiloxane and a guanidyl-containing organosilane or polysiloxane compound as a curing catalyst. The composition is capable of giving a cured rubbery elastomer when kept in a moisture-containing atmosphere at room temperature without the problems in the prior art compositions such as noxious condensation products or poor adhesion to the surface of the substrate on which the composition has been cured. The above mentioned organocyclopolysiloxane having alkenyloxy groups along with one or more of trihydrocarbylsiloxy groups or, typically, trimethylsiloxy groups bonded to the silicon atoms in the ring structure is a novel compound not described in any prior art literatures.