Polyaryl sulfones

STYRENE-ACRYLONITILE AMINOPLASTICS POLYARYL ETHER POLYARYL SULFONE... 

Nylon, polyacetal, polycarbonates, poly(2,6-dimethyl)phenylene oxide (PPO), polyimides, polyphenylene sulfide (PPS), polyphenylene sulfones, polyaryl sulfones, polyalkylene phthalates, and polyarylether ketones (PEEK) are stiff high-melting polymers which are classified as engineering plastics. The formulas for the repeating units of some of these engineering plastics are shown in Figure 1.15. 

Most polyaryl sulfones have the following repeating unit ... 

As shown in Table 15.8, polyaryl sulfones have excellent mechanical properties. The commercial products differ somewhat in properties, but all have high heat deflection temperatures (at least 175 C). These thermoplastic engineering polymers have excellent resistance to nonoxidizing acids, salts, and alkalis, and to polar solvents. They are attacked by nonpolar solvents such as benzene. 

Polyaryl sulfones are injection moldable or extrudabie on standard processing equipment. These plastics are used for meter housings, light fixture sockets, aircraft components, household appliances, hardware, and film. 

Fortunately, the deficiencies of both the classic thermosets and general purpose thermoplastics have been overcome by the commercialization of a series of engineering plastics including polyacetals, polyamides, polycarbonate, polyphenylene oxide, polyaryl esters, polyaryl sulfones, polyphenylene sulfide, polyether ether ketones and polylmides. Many improvements in performance and processing of these new polymers may be anticipated through copolymerization, blending and the use of reinforcements. 

There are several types of polyaryl sulfones available commercially. The classic polysulfone (Udal) was produced by the nucleophilic displacement of the chlorine substituents on bis(p-chlorophenyl) sulfone by the sodium salt of blsphenol A.Another polysulfone (Astrel) is produced by the Friedel-Crafts condensation of biphenyl with oxy-bis(benzene sulfonyl chloride). Another polysulfone (Vitrex), is produced by the alkaline condensation of bis(chlorophenyl) sulfone. (28.)Blends of polysulfones with ABS (Arylon, Mlndel) and SAN (Ucardel) are available. 

The structure of the repeating unit in a typical polyaryl sulfone is... 

As an example of fractality displayed in polymers at a macroscopic level (a secondary structural element), we shall consider the growth of a crack in a film of amorphous vitreous polyarylate-sulfone [100] (see Figure 11.6). 

Aromatic copolyester TP Polyaryl ether Polyaryl sulfone (PAS)... 

All commercialized polyether sulfones have aromatic groups, sulfone residues, and ether groups in the main chain. Depending on the company producing them, they are known as polysulfones, polyaryl sulfones, polyether sulfones, or polyaryl ethers. The five commercially available polyether sulfones consist of a polymer with the monomeric unit, I, a polymer with the monomeric unit I in excess over the monomeric unit II, an alternating copolymer of I and II, a copolymer of I and II with II in excess, and a polymer with the repeating unit III ... 

Polyaryl sulfones can be produced by Friedel-Crafts type reactions... 

Sauers, M.E., Polyaryl Sulfones, in Engineering Plastics, vol. 2, Engineered Materials Handbook, ASM International, Metals Park, OH, 1988, p. 146. 

Polyetherimide (PEI), Polyamide-imide, Polyetheretherketone (PEEK), Polyaryl Sulfone, and Polyethersulfone (PES)... 

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