Organometallic monomers

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... 

Only a few examples of the cationic polymerization reactions of organometallic monomers have been reported in the literature. 

A large number of vinyl organometallic monomers have been prepared, homopolymer-ized, and copolymerized with classic vinyl monomers by Pittman and others. These include polymers containing Mo, W, Fe, Cr (structure 11.33), Ir, Ru, Ti (structure 11.34), Rh (structure 11.35), and Co. 

An alternate synthetic approach to organometallic polymers is to perform reactions where the metal atom is not the reaction site. An example is a polyesterification between an organometallic monomer containing two carboxyl groups and a diol (Eq. 2-238). Reaction of the diacid with a diamine would yield an organometallic polymer via polyamidation. A wide range of other reactions covered in this chapter can be used to synthesize organometallic polymers. 

Organometallic compounds containing polymerizable carbon-carbon double bonds have been synthesized and their polymerization studied [Archer, 2001 Pittman et al., 1987]. Among the organometallic monomers studied are vinylferrrocene and trialkyltin methacrylate. Much of the interest in these polymerizations has been to obtain polymers with... 

Plasma polymers are deposited on surfaces in contact with a glow discharge of organic or organometallic monomers, in the form of a thin film and/or as a powder. Such films find applications as surface modifiers and in applications where the bulk properties of extremely thin films are desirable. 

Related organometallic monomers, such as the cyclopentadienylchromium complexes, shown as 6.7 and 6.8, have also been homo- and copolymerized, using free radical initiation.7 Here, too, the transition metal in 6.7 generates an electron-rich vinyl group which deactivates the monomer. 

Addition polymerization of ferrocene-containing vinyl monomers is probably the earliest preparation method that has been widely studied. Vinylferrocene 1 [5], the first organometallic monomer, was synthesized in 1955 and its polymerization behavior has been extensively studied under radical [5, 6], cationic [7], and Ziegler-Natta conditions [7] it is inert to anionic initiation [8]. 

Since the yield in the oxidative coupling is practically quantitative, the oxidative polymerization of a,( )-diethynyl monomers would be expected to yield high molecular weight, linear polymers, as shown in equation (18). Hay has reported that almost any diethynyl monomer, even organometallic monomers, can be polymerized to high molecular weight polymers in Ae presence of a soluble amine complex catalyst of a copper(I) salt (Hay modification). ... 

A new general route to a large variety of T)5-(vinylcyclopentadienyl) organometallic monomers was achieved in cooperation with Rausch.46,54,57,76 The lithium salts of vinylcy-clopentadienide and isopropenylcyclopentadienide were prepared (respectively), from which a large variety of new monomers, including 2-18 and 24-30 and 39 were generated (see Schemes 1.3 and 1.4). This led to many polymerizations a few are mentioned here. 

In this paper we review the recent work on plasma polymerization of organometallic monomers and discuss the room temperature... 

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