POLYMERIZATION OF MONOMERS CONTAINING FUNCTIONAL SILYL GROUPS .9. ANIONIC LIVING POLYMERIZATION OF (4-VINYLPHENYL)(N,N-DIETHYLAMINO)DIMETHYLSILANE

Anionic polymerization of (4-vinylphenyl)(N,N-diethylamino)dimethylsilane (4) was investigated in THF at -78-degrees-C with oligo(alpha-methylstyryl)lithium, -dilithium, or-dipotassium. The reaction mixtures were always red, similar to that observed in the living polystyrene. The polymerization of 4 proceeded well to give the polymer in a quantitative yield with each of these initiators. Since the polymer of 4 obtained was very sensitive to moisture, in order to characterize the molecular weight and molecular weight distribution it was converted to the more stable poly[(4-vinylphenyl)(2-propoxy)dimethylsilane]. The resulting polymers were found to possess predictable molecular weights and narrow molecular weight distributions. This strongly suggest that the polymerization of 4 proceeds without chain transfer and termination reactions to afford a "living polymer". From the direct colorimetric titration of the colored reaction mixture, it was found that the polystyryl anion derived from 4 was stable in THF -78-degrees-C after 24 h but gradually deactivated to lose ca. 20% of the original anion at 30-degrees-C after 0.5 h.