Polyphenylsilsesquioxane, ladder

The distillation of toluene, which is accompanied by the condensation of trihydroxyphenylsilane, thus forming ladder polyphenylsilsesquioxane. Since the second stage of alcoholysis forms not only trihydroxyphenylsilane, but also acetoxydihydroxyphenylsilane, it is natural that the condensation forms ladder polyphenylsilsesquioxane with a defective structure (a link-varied polymer with a certain number of linear and branched elements in the chain). 

Polyphenylsilsesquioxane will be excluded. This polymer has a ladder-type structure, two bonds connecting each repeat unit to repeat units on its left and right. Ladder-type polymers are outside the scope of this work. 

Rigid rod ladder polymer, consisting of two parallel chains of polymer regularly joined by covalent bonding, viz., pyrrones, polyquinoxalines, and polyphenylsilsesquioxane. 

Zhang, Z.-X. Hao, J. Xie, P. Zhang, X. Han, C. C. Zhang, R., A Well-Defined Ladder Polyphenylsilsesquioxane (Ph-LPSQ) Synthesized via a New Three-Step Approach Monomer Self-Organization-Lyophilization-Surface-Confined Polycondensation. Chem. Mater. 2008, 20,1322-1330. 

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