Aromatic polymers, highly

Imai, Y. Synthesis of novel organic-soluble high-temperature aromatic polymers. High Perfom. Polym. 7(3), 337-345 (1995). 

The common feature of the p-phenylene group stiffens the polymer backbone so that the polymers have higher TgS than similar polymers which lack the aromatic group. As a consequence the aromatic polymers tend to have high heat deformation temperatures, are rigid at room temperature and frequently require high processing temperatures. 

Although the structure is polar much of the polarity is frozen in at normal service temperatures. In such conditions electrical insulation properties are quite good even at high frequencies. As with many aromatic polymers, tracking resistance leaves something to be desired. 

Good electrical insulation properties with a high dielectric strength and good microwave transparency but with a low tracking resistance typical of aromatic polymers with a high C H ratio in the structure. 

No discussion of polymer fire retardance would be complete without at least a brief mention of the highly aromatic polymers, all of which are very difficultly flammable if they burn at all (1 ). Although the low flammability of phenolic and furane resins are well known, these thermally... 

Nish, A. Hwang, J.-Y. Doig, J. Nicholas, R. J., highly selective dispersion of single-walled carbon nanotubes using aromatic polymers. Nat. Nano. 2007, 2, 640-646. 

Wholly aromatic polymers are thought to be one of the more promising routes to high performance PEMs because of their availability, processability, wide variety of chemical compositions, and anticipated stability in the fuel cell environment. Specifically, poly(arylene ether) materials such as poly-(arylene ether ether ketone) (PEEK), poly(arylene ether sulfone), and their derivatives are the focus of many investigations, and the synthesis of these materials has been widely reported.This family of copolymers is attractive for use in PEMs because of their well-known oxidative and hydrolytic stability under harsh conditions and because many different chemical structures, including partially fluorinated materials, are possible, as shown in Figure 8. Introduction of active proton exchange sites to poly-(arylene ether) s has been accomplished by both a polymer postmodification approach and direct co-... 

Fuel, oxygen, and high temperature are essential for the combustion process. Thus, polyfluorocarbons, phosphazenes, and some composites are flame-resistant because they are not good fuels. Fillers such as alumina trihydrate (ATH) release water when heated and hence reduce the temperature of the combustion process. Compounds such as sodium carbonate, which releases carbon dioxide when heated, shield the reactants from oxygen. Char, formed in some combustion processes, also shields the reactants from a ready source of oxygen and retards the outward diffusion of volatile combustible products. Aromatic polymers, such as PS, tend to char and some phosphorus and boron compounds catalyze char formation aiding in controlling the combustion process. 

The market for fluoroaromatics, with fluorine atoms as ring substituents, has expanded considerably over the past 20 years, driven not only by the need for intermediates in pharmaceutical and crop protection products but also for the manufacture of monomers for high-performance aromatic polymers. Although a range of possible methods have been described for the introduction of fluorine into the aromatic ring, only three are currently established for... 

Polysulfones are both aliphatic and aromatic polymers that are resistant to high temperatures and are very stable. 

In addition to the high-pressure polycondensation reactions mentioned above, we have studied the high-pressure polyaddition for the synthesis of high-temperature aromatic polymers such as polyaminoimide from bismaleimide and aromatic diamine, polycyanurates from aromatic dicyanates, and polyiso-cyanurates from aromatic diisocyanates [34,36-40]. 

Highly branched aromatic polymers prepared by single step syntheses [Y. H. Kim, Macromol. Symp. 1994, 77, 21-33]. 

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