A synthetic route to polysilaethers containing moiety Si-H bonds in the side chain (PSEMH) is reported that allows access to hitherto inaccessible oxygen-interrupt polysilanes. By a Wurtz reductive coupling reaction, an equimolar ratio of dichloromethylsilane to alkali metal yields dichlorodisilane. The alcoholysis of Wurtz coupling resultants is in situ performed, and the polycondensation of hydrolysis occurs simultaneously in the presence of a small amount of NN-(dimethylamino)pyridine. The linear polymer is monomodal PSEMH with molecular weights as high as 24,900. The ultraviolet absorption at 292 nm is due to the interactions of the sigma(Si-Si) orbital electron delocalization and the p pi((O))-sigma*pi((Si-O)) delocalization along the (SiSiO)n skeleton. It is redshifted in comparison with those of permethyl polysilaethers analogues and blueshifted in comparison with those of poly(dialkylsilane)s. The fluorescence emissions of the polysilaethers containing moiety Si-H bonds in the side chain are in a narrow range of 300-400 nm. Si-H bonds in polysilaethers play an important role in hydrosilylation reactions. The polysilaethers containing moiety Si-H bonds in the side chains can be used as the starting point for further functionalization via hydrosilylation. (c) 2005 Wiley Periodicals, Inc.