Metallocene-containing polymers

Ferrocene is a very robust organometallic complex that has been incorporated into an impressive number of molecules with various applications and properties. Therefore, ferrocene-containing polymers have been pursued for many possible applications by different routes. Three metathesis-based approaches toward metallocene-containing polymers (mainly ferrocenes) have been reported so far (i) homo-ROMP or co-ROMP of olefins bearing a metallocenyl substituent, (ii) ROMP of strained an.ya-metallocenes, and (iii) ADMET polymerization of bis(alkenyl)metallocenes, including ADMET copolymerization with a.ty-dienes. 

Metallocene-containing polymers are often related to prominent ferrocene and cobaltocene [136-139]. Work in this area has been reviewed recently [140-142]. Therefore, the following serves as an overview. 

Hiickel band calculations, rigid-rod transition metal-acetylide polymers, 12, 371-372 Human health, tin toxic effects, 12, 637 Hybrid magnets, metallocene-containing bimetallic M(II)—Cr(II) oxalates, 12, 427 bimetallic M(II)-Fe(III) oxalates, 12, 432 bimetallic M(III)-Ru(III) oxalates, 12, 435 materials, 12, 437 properties, 12, 425 trimetallic oxalates, 12, 436 Hydantoins, with lead reagents, 3, 888 Hydration... 

A number of organometallic polymers containing metallocenes and metallocene analogues has been well-known for some time2. Because of the features of high-temperature stability and radiation resistance of the ferrocene nucleus, ferrocene-containing polymers are of special interest. Basically, these polymers may be divided into two classes the metallocene moiety is either located in a pendant group or in a backbone of the polymer chain. The former polymers have been synthesized by vinyl polymerization of vinyl metallocene monomers such as vinylferrocene. The latter polymers have been prepared by polycondensation of l,l -disubstituted metallocenes or metallocene dihalides with a.w-disubstituted monomers, and fell into two main types, (A) and (B). 

One of the syntheses of the polymers of type (A) and (B) involves the polycondensa-tion of a metallocene-containing Lewis base or Lewis arid71. A number of ferrocene-and cobalticenium-containing Lewis bases have been employed, e.g. ... 

Metallocene polymers, which contain a metal sandwiched usually between the cyclopentadienyl moieties, are the most investigated M—C-containing polymers ". Ferrocene containing metallocenes are by far the most studied, followed by cobalticen-ium, with some work where the metal is Ni, Rh, Ro or Ru. 

Cobalticenium salt containing polymers offer the advantages of good resistance to strong acids, bases and oxidation, but the disadvantages of salt exchange. The metallocenes utilized exhibit some catalytic properties that may be transmitted into polymers containing these metallocenes - . ... 

A variety of other organic polymers with metallocene-containing side-groups have been synthesized. However, very few of the materials have been as well studied as PVEc. Crystalline organometallic complexes containing ferrocene... 

Many examples of inorganic polymers with metallocene-containing side-groups also exist. Most of the polymers prepared have been based on main chains of polyphosphazenes, polysilanes, polysiloxanes, and polycarbosilanes. These materials are surveyed in the following sections. 

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