Nonconjugated polymers

Cyclopolymerization of Nonconjugated Dienes. Cyclopolymerization is an addition polymerization that leads to introduction of cyclic structures into the main chain of the polymer. Nonconjugated dienes are the most deeply studied monomers for cyclopolymerization and for cyclocopolymerizations with alkene monomers 66 In general, (substituted and unsubstituted) dienes with double bonds that are linked by less than two or more than four atoms cannot undergo efficient cyclization and result in crosslinked materials.12 In fact, efficient cyclopolymerization processes have been described, for instance, for a,oo-dienes like 1,5-hexadiene, 2-methyl-l,5-hexadiene, 1,6-heptadiene, and 1,7-octadiene,67 73 which lead to formation of homopolymers and copolymers containing methylene-1,3-cycloalkane units. 

Glatzhofer, D.T. Deshpande, S. Conducting polymers (nonconjugated). In Encyclopedia of Materials Science and Technology Buschow,... 

Ethylene-propylene-diene rubber is polymerized from 60 parts ethylene, 40 parts propylene, and a small amount of nonconjugated diene. The nonconjugated diene permits sulfur vulcanization of the polymer instead of using peroxide. 

The polymerization of nonconjugated diene monomers might be expected to afford polymer chains with pendant unsaturation and ultimately, on further reaction of these groups, crosslinked insoluble polymer networks. Thus, the finding by Butler et a .,, 03, n5 that polymerizations of diallylammonium salts, of general structure 8 [e.g. diallyldimethylammonium chloride (9)] gave linear saturated polymers, was initially considered surprising. 

Nonconjugated polymers containing flexible backbones such as 43 are generally more soluble in common organic solvents titan the rigid, conjugated polymers36 ... 

A brief review of related syntheses of conjugated polymers from nonconjugated precursor polymers is also given. 

The soluble nonconjugated precursor polymer route to Durham polyacetylene via thermal elimination. 

Figure 4. General scheme of irreversible redox elimination reaction on the class of nonconjugated polymers containing alternating -C(R)H- and conjugated sections in the main chain yielding conjugated polymers.

The two limiting structural forms of polyaniline are shown in Figure 12B (i) the nonconjugated leuco base polymer in which the... 

Figure 13 shows the irreversible conversion of a nonconjugated poly (p-phenylene pentadienylene) to a lithiun-doped conjugated derivative which has a semiconducting level of conductivity (0.1 to 1.0 S/cm) (29). Obviously, the neutral conjugated derivative of poly (p-phenylene pentadienylene) can then be reversibly generated from the n-type doped material by electrochemical undoping or by p-type compensation. A very similar synthetic method for the conversion of poly(acetylene-co-1,3-butadiene) to polyacetylene has been reported (30), Figure 14. This synthesis of polyacetylene from a nonconjugated precursor polymer containing isolated CH2 units in an otherwise conjugated chain is to be contrasted with the early approach of Marvel et al (6) in which an all-sp3 carbon chain was employed.

Nonconjugated Polymer Containing Oligo(Phenylene Vinylene)... 

The conjugation length and the emission color of PPV-type materials can be also controlled by using short oligo(phenylene vinylene) units as pendant substituents in nonconjugated polymer chain. The advantage of such an approach is the possibility to use well-established... 

In the previous sections, we described three main classes of LEP PPV, PF, and PTs, although many other conjugated and nonconjugated polymers have also been used as EL materials for LEDs. Without making an attempt to cover all types of polymers ever used as EL materials, we describe below the most important classes and the most prominent examples of EL polymers, not covered in the previous sections. Some more examples of such systems can be found in recent reviews on blue LEPs [227], polycarbazoles [571], and the general topic of organic EL materials [6,10,20]. 

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