Photopolymerisation of styrene initiated by triphenyl bismuthonium ylide

Photopolymerization of styrene initiated by tetraphenyl cyclopentadiene triphenyl bismuthonium ylide in dioxane was carried out in the presence of visible light (440 nm) at 30 ± 0.2°C for 55 h. The polymerization was inhibited by the presence of hydroquinone which is an evidence of the fact that polymerization takes place by radical mechanism. The system follows ideal radical kinetics (R_p ∝︁ I]^0.5 M]). The values of average degree of polymerization (P_n) decreases with the ylide. The mechanism of the reaction was elucidated by GPC and ESR techniques.