Other Silicon Containing Polymers

Polymers, Aproperty Database. CRC Press, Boca Raton, 2000. 

2 OTHER SILICON CONTAINING POLYMERS - General aspects 

The polysiloxane sequence can be shorter or longer, the compounds with about 20% carborane being typicaly used. Polycarborane siloxanes have high resistance to heating and are used for various purposes, including stationary phases for gas chromatography [2] and in medical applications. 

Besides poly(siloxanes), a few other silicone containing polymers have been synthesized. One such polymer is poly(dimethy-1,4-silphenylene). Thermal decomposition of this polymer at 400° C in argon [3] generates methane, dimethylsilane, benzene, dimethylphenylsilane, HSi(CH3)2-C6H4-SiH(CH3)2, H(Si(CH3)2-C6H4)2-H, dimethyl-diphenylsilane, and C8H4-(Si(CH3)2-C6H4)2H. 

Another special type of silicone containing polymers is polysilazanes. These materials are used in for the preparation of high performance ceramics, silicon nitride, etc. Polysilazane can be prepared from substituted methylchlorodisilanes and gaseous ammonia in the following reaction [4]  

The most important class of silicon-containing polymers that have not yet been covered are the polysilazanes, shown in 7.1. These polymers, or precursors to them, are generally prepared by the reaction of organic-substituted chlorosilanes with ammonia or amines as is shown in reaction (l).32 

Such molecules can also be formed by the dehydrocoupling reaction catalyzed by bases or transition metals (reaction (2))  

Another possibility is to use a deamination/condensation reaction, as shown in reaction (3). 

As a final alternative, a redistribution reaction, as illustrated in reaction (4), can be employed. 

The application of these approaches to the formation of the corresponding polymers is illustrated by reaction (5)32 

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Polycarbosilanes are an interesting class of polymers from a materials standpoint however, they do not occur naturally. A variety of synthetic methods can be employed to produce such polymers, but this part of the chapter will focus on using ADMET as a viable route to synthesize polycarbosilanes, siloxanes, and other silicon-containing polymers. 

Polysiloxanes and other silicon containing polymers form a group of inorganic-organic type polymers with many practical uses. Polysiloxanes, also known as silicones, are the most common polymers in this class. They have a backbone formed from a chain... 

Poly(siloxanes) and Other Silicon Containing Polymers... 

Poly(siloxanes) and other silicon containing polymers... 

Chandrasekhar V (2005) PolysUanes and other silicon containing Polymers. In Inoiganic and... 

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