Transition metal-containing polymers synthesis

In the following sections some examples are given of the ways in which these principles have been utilized. The first example is the use of these techniques for the low temperature preparation of oxide ceramics such as silica. This process can also be used to produce alumina, titanium oxide, or other metal oxides. The second example describes the conversion of organic polymers to carbon fiber, a process that was probably the inspiration for the later development of routes to a range of non-oxide ceramics. Following this are brief reviews of processes that lead to the formation of silicon carbide, silicon nitride, boron nitride, and aluminum nitride, plus an introduction to the synthesis of other ceramics such as phosphorus nitride, nitrogen-phosphorus-boron materials, and an example of a transition metal-containing ceramic material. 

Styrene-divinyl benzene resins have been used as typical support for the metal containing catalysts bound to them. The synthesis of these polymeric reagents has involved several approaches depending on the application which they are intended. The immobilization of transition metals on polymer supports involves using polymers containing ligands which can complex with the metal such that the coordination sphere of the metal remains essentially the same as in... 

We recently reported the synthesis of transition metal containing polyamides and polyureas [9], utilizing low temperature interfacial and solution techniques. We have now attempted to extend the solution method to the synthesis of boron containing polymers, viz. [lO]. These polymers are of increasing interest as potential precursors for B-N-C type ceramic materials [10], particularly in fiber form. 

General Procedure for the Synthesis of the Quinoline Polymers. In a flame-dried 500-mL Schlenk flask under nitrogen are placed 27b and 5b, 1 mol% of (Ph3P)2PdCl2, 1 mol% of Cul, and piperidine (15mL). The reaction mixture was stirred for 48 h. For workup, chloroform (3 x 50 mL) was added. The solution was washed with water and NH4OH to remove the transition-metal-containing catalyst residues. Removal of solvent and addition of methanol (400 mL) precipitates the polymers, which are isolated by filtration and vacuum dried. 

This volume begins with a general review that includes an overview of the general types of polymers already synthesized. Different approaches to their synthesis and background information are included to help the reader to understand transition metal-containing macromolecules. This information provides an introduction to both Volumes 6 and 7 of this series. Activity in this important area is increasing exponentially. New materials, properties, synthetic routes, and common applications constitute the root of this rapid development. 

Two major approaches to the formation of materials of this type have involved the derivatization of preformed organic polymers with organometallic functions and the synthesis and polymerization of organometallic monomers that contain vinyl substituents For the transition metals, condensation polymerizations have also been investigated. However, the reactions have generally been conducted at elevated temperatures, and the resulting products have often not... 

Similar to olefins, acetylenes undergo facile addition reactions. Transition metal-catalyzed hydrosilylation is such a reaction that has been utilized for the synthesis of silicon-containing hyperbranched polymers. 

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