PHOTOPOLYMERIZATION OF METHYL-METHACRYLATE SENSITIZED BY TRIS(2,2'-BIPYRIDINE)IRON(III)

The photopolymerization of methyl methacrylate (MMA) sensitized by tri s(2,2'-bipyridine)iron(III) complex, [Fe(bpy)(3)](3+), was studied at 35 degrees C in the presence of an electron donor, triethylamine (TEA) with UV radiation Of wavelength 254 nm. The initial rate of polymeriz ation, R-p, shows a linear dependence on [MMA] with an exponential val ue of 1.8 +/- 0.04. R-p varies linearly with the square root of the ph otosensitizer concentration up to 2.00 x 10(-4)moll(-1), and above thi s concentration, R, decreases with the increase of photosensitizer con centration. The fate of polymerization is not affected by the concentr ation of the co-initiator, [TEA]. A suitable mechanism for the reactio n is proposed to explain the kinetics of the reaction.