Polyphenylene sulfide compounds

The electrical properties of the three polyphenylene sulfide compounds are given In Table IV. The 40% glass-filled PPS Is the best Insulator as Indicated by the dielectric constant of 3.8. 

Electrical properties of polyphenylene sulfide compounds are summarized in Table III. The dielectric constant of 3.1 is low in comparison with many other plastic materials. Similarly, the dissipation factor is very low. Dielectric strength ranges from about 500-600 volts per mil for the various compounds these values are quite high. Thus, both... 

Table III. Electrical Properties of Polyphenylene Sulfide Compounds...

Ryton Polyphenylene Sulfide Compounds Engineering Properties ,... 

Polyphenylene sulfides are inherently resistant to UV, weathering and hydrolysis. Black compounds are the most UV-resistant. 

Most polyphenylene sulfides are fire resistant with oxygen indices ranging from 45 up to 57 and a UL94 rating of VO. Rarely, a few compounds are reported to have a UL94 rating of HB with an oxygen index of 25. 

Production, Import/Export, Use, Release, and Disposal. Data on the production and uses of 1,4-dichlorobenzene in the United States are available (C EN 1995 Chemical Marketing Reporter 1990 HSDB 1998 IRPTC 1985 SRI 1996 TRI96 1998). Production has increased over the past decade and is projected to increase for the next several years due to an increased demand for 1,4-dichlorobenzene to be used in the production of polyphenylene sulfide (PPS) resins. Incineration is the recommended disposal method for 1,4-dichlorobenzene (HSDB 1998 IRPTC 1985). Disposal of this compound is controlled by... 

The routes give, using well-known condensation and radical reactions, bakelites (I), polyazophenylenes (II), polyimides (III), polyurethanes (IV), nitro compounds and polyamides (V), aromatic polyethers and polyesters (VI), polychalcones (VII), polyphenylene sulfides (IX), ammonia lignin (X), carbon fibers (XI), silicones (XII), and phosphorus esters (XIII). In addition, radiation and chemical grafting can be used to obtain polymers of theoretical interest and practical use. Although the literature on the above subject is very large, there are comprehensive summaries available (1,28,69). 

A commercial process for polyphenylene sulfide, (-( S-)x, was developed in 1967 by the reaction of para-dichlorobenzene and sodium sulfide in a polar solvent (1)- This polymer is very versatile. Selected grades can be used for extrusion and for production of a wide range of injection molding compounds. Typical properties of a 40% glass-reinforced compound are given in Table I. 

Polyphenylene sulfide has very good resistance to acids and bases. Formic acid decreases the tensile strength by 25%. Resistance to alcohols and glycols is excellent. Of all the classes of organic compounds tested, amines cause the most deterioration in tensile strength. 

In the Phillips process, polyphenylene sulfide (PPS) is obtained from the polymerization mixture in the form of a fine white powder, which, after purification, is designated Ryton V PPS. Characterization of this polymer is complicated by its extreme insolubility in most solvents. At elevated temperatures, however, Ryton V PPS is soluble to a limited extent in some aromatic and chlorinated aromatic solvents and in certain heterocyclic compounds. The inherent viscosity, measured at 206°C in 1-chloronaphthalene, is generally 0.16, indicating only moderate molecular weight. The polymer is highly crystalline, as shown by x-ray diffraction studies (9). The crystalline melting point determined by differential thermal analysis is about 285°C. 

PTFE can be compounded with polymeric fdlers with adequate thermal stability. Examples of such polymers include polyarylates such as polyether-ketone, polyphenylene sulfone, and polyphenylene sulfide. Surface characteristics such as wear rate, coefficient of friction, and surface tension can be modified with these additives. 

In thermoplastics, carbon fiber compounds have been developed with nylon, polysulfone, thermoplastic, polyester, polyphenylene sulfide, polycarbonate, polypropylene, polyamide-imide, and ethylene/tetrafluoroethylene copolymer. Carbon fiber-reinforced molding compounds are available with carbon fiber contents of various levels such as 20, 30, and 40 weight percent. Nylon 66 molding compounds have also been developed with hybrid combinations of carbon and glass fiber reinforcements. 

Spinney, L. J., Orroth, S. A., and Malloy, R. (1979) Regrind study on a polyphenylene sulfide molding compound, SPE RETEC, 126-129. 

Ryton PPS—Polyphenylene Sulfide Res- 45. ins—Properties and Uses of Anti-Friction Compounds, TSM-262, Phillips Petroleum Company, Bartlesville, OK, October 1974. 

The compound 1,4-dichlorobenzene (CAS 106-46-7) is most commonly referred to as para-DCB or p-DCB. It is widely used as a moth killer, in space deodorizers, and in the production of polyphenylene sulfide. It is also used in the manufacture of certain resins, in the pharmaceutical industry, and as a general insecticide in farming. Synonyms for 1,4-dichlorobenzene are 1,4-dichlor-B benzene, 1,4-dichloro benzene, p-dichloro dichlorobenzene, para, solid p-chlorophenyl chloride p-DCB p-dichlorobenzene p-dichlorbenzol parazene PDB para-DCB paradichlorobenzene and paradichlorobenzol. At room temperature, 1,4-dichlorobenzene is a white or colorless crystalline solid with a characteristic penetrating odor. When exposed to air, it is slowly transformed from its solid state into a vapor the released vapor then acts as a deodorizer and insect killer. It is practically insoluble in water and is soluble in alcohol, acetone, ether, chloroform, carbon disulfide, and benzene. Its chemical formula is C6H4CI2. 

RYTON polyphenylene sulfide resins and compounds are engineering thermoplastics developed by Phillips Petroleum Company. Available in both molding and coating grades, these materials feature excellent dimensional stability, inherent flame retardancy, thermal stability, chemical resistance, desirable electrical properties and ease of processing. 

When processing polyphenylene sulfide, it is necessary to vent injection molds appropriately, because the sulfurous degradation products cause mold corrosion. Because of the low melt viscosity the vent holes have to be narrow (flash formation). That is why poorly stabilized compounds require frequent and quite involved mold purging [573]. 

Weight loss and sulfurous gas emission during thermal-oxidative degradation of 600 mg polyphenylene sulfide (1 wt.% U2CO3 as adsorbent for sulfurous compounds) [626]... 

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