Polysilanes, cyclic structural studies

We have been recently studying new pathways leading to polysilanes with low polydispersity and controlled structures. Our research is focused on three areas. The first one is low temperature reductive coupling in the presence of ultrasound. This leads to monomodal polymers with molecular weights in the range from Mn=50,000 to Mn=300,000 and polydispersities as low as Mw/Mn=1.20 (in addition to usually formed cyclic oligomers). 

The cyclic polysilanes are all colorless crystalline solids, and several have now been studied by X-ray crystallography. The structures of those with ring size 3 to 6 have recently been summarized and discussed by Watanabe and coworkers35. 

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