Polysiloxane overview

This chapter is meant to be an overview of ongoing studies of polysiloxane-modified epoxy resins. Because this research area is still quite young, it is not yet possible to write a standard review article. Presented here is the current status of a collaborative effort encompassing chemistry and synthesis of the modified networks, their morphology, their mechanical properties, and their friction and wear behavior. The earliest work in the synthesis and characterization of siloxane-modified networks was done by Riffle et al. 15). More recent research in the area of chemistry and synthesis has been carried out by Tran 17). 

This article presents an overview of our experience using these catalysts in the case of alkenes bearing functional groups, such as esters, acids, amines, alcohols or carbamates. It is divided in three parts. The first one describes the formation of liquid crystal polysiloxanes or elastomers by the grafting of liquid crystal moieties. 

High Refraction Index Polysiloxanes via Organometallic Routes - An Overview... 

Fig. 13. Overview over some properties to be derived from inorganic-organic hetero polysiloxane nanocomposites and potential applications...

Aryl- and alkylsulfonated polysiloxanes are available. Aryl sulfonated polysiloxanes are generally synthesized by sulfonation of solid aryl polysiloxanes whereas alkyl sulfonated polysiloxanes are synthesized by starting either with an aqueous solution of the sulfonic acid-functionalized silane or with a highly crosslinked mercapto or polysulfan functionalized polysiloxane. Figure 3 gives an overview of the predominantly synthesized sulfonated siloxane units. 

The polysiloxanes are by far the most important polymers in the category of inorganic or semi-inorganic polymers, with a large industry devoted to them in numerous countries in the industrialized world. This book attempts to give an overview of these polymers, and to describe some unsolved problems in this area. 

Polysiloxanes are the most widely used stationary phases for packed- and capillary-column GC. They offer high solute diffusivities coupled with excellent chemical and thermal stabilities. The thorough review of polysiloxane phases by Haken (105) and the overview of stationary phases for capillary GC by Blomberg (106,107) are strongly recommended readings. 

Of the semi-inorganic polymers, the siloxane or "silicone polymers have been studied the most, and are also of the greatest commercial importance (i-i5). The present review provides an overview of some of these polysiloxanes and related materials, emphasizing their structures, most important and interesting physical properties, and a variety of their applications. 

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