Bridged polysilsesquioxanes

Bridged polysilsesquioxanes having covalently bound acidic groups, introduced via modification of the disulfide linkages within the network, were studied as solid-state electrolytes for proton-exchange fuel cell applications.473 Also, short-chain polysiloxanes with oligoethylene glycol side chains, doped with lithium salts, were studied as polymer electrolytes for lithium batteries. 

A second method that has been described as a means to deal with the limited accessibility issue involves a copolymerization route. In this approach, the porous matrix is copolymerized with the template. Burleigh and coworkers, for example, described the preparation of imprinted polysilsesquioxanes for the recognition of metal ions.79 Polysilsesquioxanes are hybrid porous materials synthesized from bridged alkoxide precursors such as shown in Figure 20.2.80 In this example, the bridged silsesquioxane precursors were copolymerized with the metal ion complex in the presence of surfactant. Once the surfactant and metal ion were removed, a porous network was formed that showed a high affinity for the metal ion.79... 

C. Chuit, R. J. P. Corriu, G. Dubois, and C. Reye, Hybrid organic-inorganic materials. Preparation and properties of dibenzo-18-crown-6 ether-bridged polysilsesquioxanes, Chem. Commun. 723-724 (1999). 

A new class of hydride organic/silica compounds such as organically bridged polysilsesquioxanes 213 were prepared from the hydrolysis and condensation of triethoxysilanes 212 linked by a hydrocarbon spacer, as shown in Equation (41). 

Scheme 12 X-ray diffraction patern of a powder of biidged-polysilsesquioxane with mesogenic group as a bridge...

Fig. 1 Images by microscopy in polarized tight of three bridged-polysilsesquioxanes (See also Plate 25 in the Colour Plate Section)...

Loy D. A. and Shea K. J., Bridged polysilsesquioxanes. Highly porous hybrid organic-inorganic materials, Chem. Rev. 96(1995), pp. 1431-1442. 

Very interesting arylene-bridged polysilsesquioxane networks were described by Loy and Shea [279] and Shea et al. [280]. Aromatic hydrocarbons containing two (or more) triethoxysilyl groups were used as the starting compounds ... 

VIIL HIERARCHICAL IMPRINTING WITH BRIDGED-POLYSILSESQUIOXANE HYBRID HOSTS [7]... 

Shea, K. J. Loy, D. A., Bridged Polysilsesquioxanes Molecular Engineering of Hybrid Organic-Inorganic Materials. MRS Bull. 2001, 26, 368-375. 

Shea K J, Loy D A (2(X)1) Bridged polysilsesquioxanes. Molecular-engineered hybrid organic-inoiganic... 

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