Silicone networks organic-inorganic hybrids

Silicone co-polymer networks and IPNs have recently been reviewed.321 The development of IPNs is briefly described, and the definitions of the main (non-exclusive) classes of the IPNs are cited. Examples of latex IPNs, simultaneous and sequential IPNs, semi-IPNs, and thermoplastic IPNs are provided. The use of silicone-silicone IPNs in studies of model silicone networks is also illustrated. Networks in which siloxane and non-siloxane components are connected via chemical bonds are considered co-polymer networks, although some other names have been applied to such networks. Today, some of the examples in this category should, perhaps, be discussed as organic-inorganic hybrids, or nanocomposites. Silicone IPNs are discussed in almost all of the major references dealing with IPNs.322-324 Silicone IPNs are also briefly discussed in some other, previously cited, reviews.291,306... 

We are nowhere close to knowing the potential benefits that nanoscale silicone resin networks, with their special structure-effect relationship, will be able to offer irmovative technologies of the future (nanotechnology). By virtue of their organic-inorganic hybrid nature, silicones open up new paths to special functionalities and enhanced properties of materials. 

Polyacrylic acid Hybrid organic/inorganic network polymers were formed via the reaction of polyacrylic acid with tin(IV). titanium(IV), and silicon (IV) alkoxides and subsequent hydrolysis to form mesoporous materials. Treatment by nitric acid removed the polyacrylate template and produced microporous inorganic hydrous metal oxides Surface areas characterized by BET measurements 130... 

Nonlinear Optical Devices. A transparent, optically active, sol—gel-derived organic—inorganic glass has been synthesized (68). This hybrid consists of a 2,4-dinitroaminophenylpropyl-triethoxysilane covalendy bound to a silicon alkoxide-derived silica network. This hybrid exhibits a strong electric field-induced second harmonic signal and showed no signs of crystallization. 

The polymerization of silicon alkoxides, Si(OR)4, to produce inorganic glasses proceeds through these three reactions and is commonly referred to as the sol-gel process. Reactions of trialkoxysilane-terminated molecules R OR 2)3 are similar and give hybrid organic-inorganic networks,... 

Figure 4 Polymer-silica hybrid materials hydrogen bonding between silanol groups of hydrolyzed silicon alkoxides and carboxylate groups of preformed poly(A, A-dimethylacrylamide) (a) or in situ polymerized A, A-dimethylacrylamide/methylene bisacrylamide precursors (b) favors the formation of homogeneous organic-inorganic networks...

Keywords Polymers / Hybrid Organic-Inorganic Polymers / Polymer Network / IPN / Hybrid Polymer Technologies / Contact Lenses / Coatings / Surfactants / Wetting Agents / Silicones / Silicone Polyimides / Siloxane Resins... 

To meet the challenges of new material requirements, scientists must strive constantly to develop new systems. One recent approach has been to prepare inorganic-organic hybrid materials by using the sol-gel method common to ceramists. This technique allows a considerable range of chemistry to be used and may lead to the development of a whole array of systems that have potential applications (structural, optical, etc.). This chapter provides an overview of the general status of this approach, with emphasis on the work that comes from our laboratory. The chemistry discussed in this chapter involves the use of silicon-containing species in the preparation of polymeric network systems. 

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