Double-decker silsesquioxane

Although the introduction of bulky and rigid organic moieties improves some expected properties, it breaks the continuity of the Si-O-Si backbone in the polymer. If double-decker silsesquioxane consisting of only siloxane bonds was introduced... 

Although polymers Pc, Ptrans, and Pmix have a high content of double-decker silsesquioxane (82 wt%), they provide excellent film qualities with high transparency. Films with thickness 50-85 [im were prepared. The optical transparency of a polymer can be seen by comparing photographs of the silsesquioxane symbol taken directly and taken through the polymer, as shown in Fig. 15 for Pdj. 

Scheme 10.4 General Procedure for Synthesis of Dialkenylsubstituted Double-Decker Silsesquioxanes.

Silsesquioxane-Based Polymers Synthesis of Phenylsilsesquioxanes with Double-Decker Structure and Their Polymers... 

Abstract Double-decker shaped silsesquioxane was synthesized by hydrolysis and condensation of trimetoxyphenylsilane in the presence of sodium hydroxide and it led to macromonomers having carbon functionalized groups. Then, these were polymerized by hydrosilylation polymerization, and their properties were measured. 

Polyhedral oligomeric silsesquioxanes (POSS) are known molecules having various structures [1] as seen in Fig. 1. However double-decker shaped silsesquioxane has not been obtained. POSS is an interesting class of monomers for the preparation of silicon-based polymers. In recent years, silsesquioxane-based polymers have received much attention because of their useful properties, which include heat resistance, mechanical stability, low dielectric constant, etc. [2, 3],... 

Synthesis of Double-Decker Shaped Silsesquioxane and its Derivatives... 

Scheme 1 Synthesis of double-decker shaped silsesquioxane...

DD-Na is easily converted into the sila-functional silsesquioxane (DD-OH). The structure of DD-OH was confirmed by Si-NMR and other spectroscopic analyses (Scheme 2) [10,11], In quite recent time, Lee reported that the double-decker shaped silsesquioxane seems to be produced with the consumption of the partial cage and the cyclic siloxanes in the same condition [12],... 

Seine M et al. (2006) Hydrosilylation polymerization of double-decker-shaped silsesquioxane having hydrosilane with diynes. Macromolecules 39 3473-3475... 

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