Hybrid materials groups

By using a similar procedure for the preparation of hybrids of silica, hybrids materials consisting of other metal oxides were also prepared by the group of Wilkes [15]. For example, titania was incorporated into organic polymers by using the chemically controlled condensation (CCC) method for the preparation of poly(tetramethylene oxide)-silica or poly(dimethylsiloxane)-silica hybrids. Especially, in the case of the hybrid with poly (tetramethylene oxide), the modulus or ultimate strength of the hybrid increased in the presence of titania component, as shown in Table 3. This phenomenon was explained by the catalytic ability of... 

Poly(oxyethylene)-Si02 ormosils have been prepared as an approach to the preparation of biologically active polymer-apatite composites. For this purpose, Yamamoto et al. [72] obtained these Class II hybrids from triethoxysilyl-terminated poly(oxyethylene) (PEG) and TEOS by using the in situ sol-gel process. After being subjected to the biomimetic process to form the bone-like apatite layer, it was found that a dense apatite layer could be prepared on the hybrid materials, indicating that the silanol groups provide effective sites for CHA nucleation and growth. 

Yamamoto, S., Miyamoto, T., Kokubo, T. and Nakamura, T. (1998) Preparation of polymer-silicate hybrid materials bearing silanol groups and the apatite formation on/in the hybrid materials. Polymer Bulletin, 40, 243-250. 

In recent years, silica sol-gel-based inorganic-organic hybrid materials have also been reported. The introduction of various functional groups into organic alkoxide has led to organically modified sol-gel glasses (ormosils). Some of the ormosil monomers and ormosil formations can be found in Fig. 16.3. Redox molecules can be coupled with the ormosil monomer functional group. The immobilized redox molecules can... 

Functional groups in silicones, 22 598 suffixes and prefixes for, 17 397t Functional hybrid materials... 

Li et al. reported first on the decoration of hydrothermal carbon spheres obtained from glucose with noble metal nanoparticles [19]. They used the reactivity of as-prepared carbon microspheres to load silver and palladium nanoparticles onto then-surfaces, both via surface binding and room-temperature surface reduction. Furthermore, it was also demonstrated that these carbon spheres can encapsulate nanoparticles in their cores with retention of the surface functional groups. Nanoparticles of gold and silver could be encapsulated deep in the carbon by in situ hydrothermal reduction of noble-metal ions with glucose (the Tollens reaction), or by using silver nanoparticles as nuclei for subsequent formation of carbon spheres. Some TEM images of such hybrid materials are shown in Fig. 7.4. 

---