THE PREPARATION OF THE MIXED ALKALI METAL SILANOLATE K4LI4(OSIME(3))(X)(OCME(3))(8-X) (8-GREATER-THAN-OR-EQUAL-TO-X-GREATER-THAN-OR-EQUAL-TO-5.7) AND THE EFFECTS OF MIXED ALKALI METALS ON THE ANION INDUCED RING OPENING POLYMERIZATION OF OCTAMETHYLCYC

摘要

The novel mixed alkali metal silanolate K4Li4(OSiMe(3))(x)(OCMe(3))(8-x) (x=6.8 (1), 5.7 (2), 8 (3)) has been prepared via the reaction of hexamethyldisiloxane with n-butyllithium and potassium t-butoxide in THF or by the reaction of KOSiMe(3) with LiOSiMe(3). Molecular weight studies show a partial dissociation to smaller clusters in solution. The mixed alkali metal compounds 1-3, as well as an equimolar mixture of KOSiMe and LiOSiMe(3), serve as unique catalysts for the anion induced ring opening polymerization of octamethylcyclotetrasiloxane in that they produce a linear polymer of relatively high molecular weight and low polydispersity. [References: 19]