Radical polymerizations of 4‐pentamethyldisilylstyrenes

Radical polymerization of 4‐pentamethyldisilylstyrene (1) and 4‐pentamethyldisilyl‐α‐methylstyrene (2) have been conducted. Monomer reactivity ratious (r1 and r2) of 1 and 2 with styrene (M1) were measured with Fineman‐Ross plots. The resonance factor (Q) and polar factor (e) of a Q–e scheme for 1 were conculated with the r1 and r2 values. The inductive effect (σI) resonance effect (σ ) of the pentamethyldisily group were monitored with the 1H‐ and 13C‐NMR spectra of 1. The magnitudes of σI and σ were found to be analogous to those of the trimethylsilyl group, indicating that the disilyl group shows a net electron‐withdrawal effect