Silicon-containing polymers polysilanes

Even though polysiloxanes are the most prominent class of silicon-containing polymers, polysilanes gained more and more interest within the last decades due to their interesting electrochemical and photophysical properties caused by the Si—Si backbone (2). Nevertheless, the synthesis of polysilanes is very sophisticated. The elaborated preparative procedures are not able to deliver polysilanes with high-molecular weight and narrow mass distributions, which is largely a consequence of the weak Si—Si bond. 

The long bonds in silicon-containing polymers can result in greater flexibility, relative to carbon-backbone polymers, as observed for PDMS. However, highly substituted all-silicon-backbone polymers (polysilanes) may be stiff despite the long Si-Si bond (2.35 A) because of large steric hindrance caused by two bulky groups on each backbone atom. 

Jones, R. G., Holder, S. J. Synthesis of polysilanes by the Wurtz reductive-coupling reaction. Silicon-Containing Polymers 2000, 353-373. 

Sakuiai H, Yoshida M (2000). Synthesis of polysilanes by new procedures Part 1 Ring-opening polymerizations and polymerization of masked disilenes. In Jones RG, Ando W, Chojnowski J (eds) Silicon containing polymers. Kluwer Academic, Dordrecht, pp 375-399... 

Jones, R. G. Holder, S. J. Synthesis of Polysilanes by the Wurtz Reductive-Coupling Reaction. In Silicon-containing Polymers The Science and Technology of Their Synthesis and Applications Jones, R. G., Ando, W., Chojnowski, J., Eds. Kluwer Academic Publishers Dordrecht, The Netherlands, 2000 pp 353-373. 

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