@wildfyr : I am looking into alternate methods of attaching the TMS protected alkyne, but right now I am just looking for a base which is strong enough to form the isopropoxide initiator, without deprotonating the alkyne.
My polymer is a polyether, and no alkenes are deprotonated in this reaction.
Reactions at the polymer chain post polymerization are highly inefficient due to the steric hindrance of the polymer.
Adding TMS later in the monomer synthesis would preferentially attack (protect) the site where polymerization would propagate.