Silphenylene polymers structures

I ILPHENYLENE-SILOXANE POLYMERS (I) are, in a sense, modified polysi-loxanes in which every third siloxyl group in the main chain backbone is replaced by a suitable silphenylene group see structure on page 742). 

Silarylene Polymers Containing m-Xvlvlene Units. A majority of the silarylene type siloxane polymers which have been worked on to date contain silicon-phenyl bonds. After an extensive literature search, only one type of polymer was found which contained an arylene group that does not have silphenylene bonds in the polymer backbone. The work, done mainly by Rosenberg and Choe 15-17 of the Air Force Materials Laboratory, is based on polymers which have a general structure as shown below, referred to as poly(m-xylylene-siloxanylenes), (9). 

Dorset, D. L. McCourt, M. P., Direct Phase Determination for Polymer Fibre X-ray Data—The Structure of Poly(tetrameth -p-silphenylene siloxane). Polymer 1997,38,1985-1988. 

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