Poly phenylene oxide synthesis

Poly(phenylene oxides), synthesis and properties of carboxylated derivatives [97]. 

Lv J, Meng Y, He L, Qiu T, Li X, Wang H (2013) Novel epoxidized hyperbranched poly (phenylene oxide) synthesis and application as a modifier for diglycidyl ether of bisphenol A. J Appl Polym Sci 128 907-914... 

Halophenols without 2,6-disubstitution do not polymerize under oxidative displacement conditions. Oxidative side reactions at the ortho position may consume the initiator or intermpt the propagation step of the chain process. To prepare poly(phenylene oxide)s from unsubstituted 4-halophenols, it is necessary to employ the more drastic conditions of the Ullmaim ether synthesis. A cuprous chloride—pyridine complex in 1,4-dimethoxybenzene at 200°C converts the sodium salt of 4-bromophenol to poly(phenylene oxide) (1) ... 

Synthesis of Poly(phenylene Oxides) by Electrooxidative Polymerization of Phenols... 

Copper-catalyzed oxidations of phenols by dioxygen have attracted considerable interest owing to their relevance to enzymic tyrosinases (which transform phenols into o-quinones equation 24) and laccases (which dimerize or polymerize diphenols),67 and owing to their importance for the synthesis of specialty polymers [poly(phenylene oxides)]599 and fine chemicals (p-benzoquinones, muconic acid). A wide variety of oxidative transformations of phenols can be accomplished in the presence of copper complexes, depending on the reaction conditions, the phenol substituents and the copper catalyst.56... 

Catalysts are also required in many stepwise polymerizations. For example, reaction of polycarboxylic acids and polyols (Reaction 7) is catalyzed by acids ester interchange, by metal compounds such as titanium alkoxides. On the other hand, polyurea synthesis (Reaction 6) generally does not require a catalyst. Metallic compounds are also useful in oxidative polymerization of phenols to give poly(phenylene oxides), illustrated in Reaction 14. 

R.Y.M. Huang and J.J. Kim, Synthesis and transport properties of thin film composite membranes. I. Synthesis of poly(phenylene oxide) polymer and its sulfonation. J. Appl. Polym. Sci., 1984, 29, 4017-4027. 

Zhang J, Wang H, Li X. Novel hyperbranched poly(phenylene oxide)s with phenolic terminal groups synthesis, characterization, and modification. Polymer 2006 47(5) 1511-8. 

R. Chandra, Recent advances in the synthesis, degradation and stabilization of poly(phenylene oxide), Progr. Polym. Sci. 8, 469(1982). 

YJ. Kim, I.S. Chung, S.Y. Kim, Synthesis of poly(phenylene oxide) containing trifluoromethyl groups via selective and sequential nucleophilic aromatic substitution reaction. Macromolecules 36 (11) (2003) 3809-3811. 

The synthesis of poly(phenylene oxides) and poly(phenylene sulfides) coordinated to pentamethylcyclopentadienylruthenium cations was described by Segal and Dembek. Dembek and coworkers found that these polymers behaved like polyelectrolytes in polar organic solvents. The trichlorobenzene and tetrachloroben-zene complexes were useful in the preparation in highly branched oiganometallic complexes. ... 

Figure 2.16 Synthesis of poly(phenylene oxide) by laccase-catalyzed oxidative polymerization of syringic acid.

Commercial polymers based on the principle of synthesis of polyaromatic compounds include the previously discussed commercial polymers—aromatic polyamides, polyimides, poly(phenylene oxide), polysulfone, and polybenzimidazole (see Chapter 1). 

Synthesis of the polymers by post-sulfonation is straightforward whenever there are electron-rich phenyl rings present in the polymer backbone or in side chains. This is, for example, the case in many poly(arylene ether ketone)s and poly(arylene ether sulfone)s, poly(phenylene oxide), poly(phenylene sulphide), certain poly(paraphenylene)s, poly(phenylquinoxaline)s, and others. However, the exact chenucal structure, such as the exact level of activation or deactivation of the aromatic groups, or the presence of acid labile groups, as well as the solubility of the starting material and the end product, deter-... 

Huang P, Gu A, Liang G, Yuan L (2012) Synthesis of epoxy-functionalized hyperbranched poly(phenylene oxide) and its modification of cyanate ester resin. J Appl Polym Sci 123 2351-2359... 

In comparison with the membranes with common aromatic skeletons such as poly-sulfane (PS), poly(ether ether ketone), poly(phthalazinon ether sulfone ketone), poly(etherimide), poly(benzimidazole), poly(phenylene oxide), polysiloxane, poly(oxyethylene) methacrylate, poly(arylene ether sulfone), and polyethersulfone Cardo, which are generally at high price and of complicated synthesis processes, the most important advantages of the aliphatic polymer materials as PEM membranes are their low cost, easy preparation, and simple structure. These aliphatic PEMs are particularly environmentally friendly (e.g., if the quatemization process is proceeded when these aromatic membranes are used for alkaline PEM fuel cells, the synthesis route uses chloromethyl ether for chloromethylation, which is very toxic and carcinogenic). However, the stability of the aliphatic PEMs is not very good. This is probably the biggest challenge when they are used in electrochemical devices. 

The poly (phenylene oxide)s can be readily modified by initially introducing substituents on the phenol or by carrying out chemical reactions on the polymers. Short reviews on this subject have recently appeared. " In this chapter we will discuss in detail the synthesis and properties of these chemically modified poly (phenylene oxide)s. 

White demonstrated the synthesis of aryloxyphenols 35 by reaction of poly (phenylene oxide)s 33 with other phenols, e.g. phenol 34, in the presence of a free radical initiator. (Scheme 12)... 

Diphenoquinones 36 can be used as initiators for the redistribution reaction. White found that equilibration of a diphenoquinone 36 with a poly (phenylene oxide) 2 would give a difiinctional polymer 37 as shown in Scheme 13. Low molecular weight PPO polymers were preferentially used since they are more free of imperfections. A simplified procedure for the synthesis of low molecular weight PPO by a precipitative polymerization reaction has recently been published. ... 

Huang and Kim reported on the kinetics involved in the synthesis of poly (2,6-dimethyl-1,4-phenylene oxide) by oxidative condensation polymerization of 2,6-dimethylphenol in o-dichlorobenzene solvent. They have also reported on the kinetics involved in sulfonation of poly (phenylene oxide) by chlorosulfonic acid in chloroform. ... 

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