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Ethers backbone configuration

The poly(phenylene oxide)s are also referred to as polyoxyphenylenes and poly(phenylene ether)s. Variations in the configuration of the ether group, ie, ortho, meta, or para, and in the extent and type of substitution, eg, alkyl, halo, etc, on the aromatic backbone give rise to a large number of possible homo- and copolymers. The polymers with para-oriented ethers have been studied most extensively and several have significant utility. Poly(2,6-dimethyl-l,4-phenylene oxide) [25134-01-4] (DMPPO), prepared by General Electric by the oxidative coupling polymerization of 2,6-dimethylphenol, is marketed as PPO resin. Blends of... [Pg.6168]

As a matter of fact, the N-substitution induced in the polymer backbone a much weaker configurational flexibility than the 3-substitution. To circumvent this problem, Moutet et al. have synthesized polypyrroles N-substituted by ferrocene crown ether [270] and aza crown ether-linked bipyridine ruthenium (II) complexes [271]. Poly(19) was found to be Ba + and Ca " "-responsive [270], whereas the ruthenium(II)-based PPy was more sensitive to alkali metal cations [271]. The recognition of the cation binding was based on the changes in the electrochemical response of the metallic center instead of PPy. [Pg.118]

Optically active copolymers of (-)-l-phenylethyl methacrylate and MA have also been prepared.The copolymer remained optically active even after removal of the optically active ester group pendent on the polymer backbone. The copolymers were not strictly 1 1 alternating materials, such as the (-)-l-phenylethyl vinyl ether-MA copolymers. The work on these optically active copolymers is an excellent demonstration of the importance of steric effects in determining the configuration of a newly formed repeating unit on a polymer backbone. [Pg.383]


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See also in sourсe #XX -- [ Pg.111 , Pg.112 , Pg.113 ]




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Backbone configuration

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