Published online by Cambridge University Press: 17 March 2011
Polystannanes, i.e. organometallic polymers of the chemical formula (SnR2)n, are relatively little explored, although they belong to the rare examples of polymers which are characterized by a backbone of metal atoms which are linked by covalent bonds. We developed a new synthetic route which yields pure linear poly(dibutylstannane) [Sn(Bu)2]n by polymerization of dibutylstannane (dibutyltin dihydride) with the catalyst [RhCl(PPh3)3]. Here, we report that the conversion and the reaction rate of dibutylstannane depends crucially on the temperature and [RhCl(PPh3)3] is also suited for the polymerization of dioctylstannane and didodecylstannane. The polymers thus obtained were characterized by 1H, 13C and 119Sn NMR spectroscopy: Orientation of all polystannanes was achieved by tensile drawing. The orientation was examined by UV-vis spectroscopy with polarized light and X-ray diffraction. Remarkably, the orientation of the backbone depended on the length of the alkyl groups.