Abstract
The flash photolysis of poly(dihexyl silylene), PDHeSi, in tetrahydrofuran solution at λinc = 347 nm (flash length: 20 ns) and ambient temperature yields silyl macroradicals that strongly absorb light at 370 nm. Recording the decay of the optical density at λobs = 370 nm rate constants of reactions of the silyl macroradicals were measured. The silyl macroradicals undergo a self reaction with a rate constant 2kR+R = 1.9×109dm3mol(1s(1). Moreover, they are highly reactive towards olefinic monomers. The following rate constants kR+M (in units of dm3mol(1s(1) were determined: 1.6×108, styrene; 1.0 × 108, acrylonitrile; 7.6×107, methyl methacrylate; 6.5×107, vinyl acetate; 1.6×107, butyl acrylate; 7.3×106, methacrylonitrile; < 105, n-butyl vinyl ether.
ACKNOWLEDGEMENTS
This work was performed in the frame of the project Acciones Integradas that is financially supported by the Governments of both Spain and Germany. Some of the authors (A. A., C. P. and F. C.) would like to acknowledge the support provided by Plan Nacional de la CICYT, Spain (MAT 98-0797).