Polymer Polyphenylene sulfide

Thermoplastic polymer polyphenylene sulfide (PPS)/BST composites were obtained with various BST contents. Particles were uniformly dispersed in PPS matrix using a twin-screw extruder, and composites with 70 wt% BST had a dielectric constant and dielectric loss of 13.5 and 0.0025, respectively, at 1 GHz [139]. Li et al. [140] embedded Bao.6Sro.4Ti03/silver core-shell nanoparticles into PVDF matrix. The silver-coated Bao.6Sro.4Ti03/PVDF nanocomposites showed 73% higher dielectric constant than composites of bare BST meanwhile, the dielectric loss was still low (less than 0.2) at 55 vol% filler content. 

As regards the general behaviour of polymers, it is widely recognised that crystalline plastics offer better environmental resistance than amorphous plastics. This is as a direct result of the different structural morphology of these two classes of material (see Appendix A). Therefore engineering plastics which are also crystalline e.g. Nylon 66 are at an immediate advantage because they can offer an attractive combination of load-bearing capability and an inherent chemical resistance. In this respect the arrival of crystalline plastics such as PEEK and polyphenylene sulfide (PPS) has set new standards in environmental resistance, albeit at a price. At room temperature there is no known solvent for PPS, and PEEK is only attacked by 98% sulphuric acid. 

Polyphenylene sulfide Melts at 270-315°C (578-599°F) crosslinked polymer stable to 450°C (842°F) in air adhesive and laminating applications. 

Note Glass filler can considerably extend the performance of the above polymers. PEI = polyetherimide PES = polyether sulfone PPS = polyphenylene sulfide PSF = polysulfone PC = polycarbonate. 

Polyphenylene sulfide Melts at 270 to 315°C (578 to 599°F) cross-linked polymer stable... 

The palladium-catalyzed formation of sulfides can generate polyphenylene sulfide from a dithiol and a dibromoarene, or from 4-bromobenzenethiol (Equation (38)).17 In 1984 Asahi Glass obtained patents for the formation of this polymer in the presence of palladium and nickel catalysts.125,126 In addition, Gingras reported palladium-catalyzed couplings of aryl halides and thiols to form discrete phenylene sulfide oligomers.127,128 A number of polyphenylene sulfide wires, ranging from dimeric to pentameric structures, were prepared by the palladium coupling, albeit in modest yields ... 

Polyphenylene sulfide is a semicrystalline and opaque polymer with the following formula ... 

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. 

Aromatic cyclic chains are more stable than aliphatic catenated carbon chains at elevated temperatures. Thus linear phenolic and melamine polymers are more stable at elevated temperatures than polyethylene, and the corresponding cross-linked polymers are even more stable. In spite of the presence of an oxygen or a sulfur atom in the backbones of polyphenylene oxide (PPO), polyphenylene sulfide (PPS), and polyphenylene sulfone, these polymers are... 

Aromatic polymers such as PS are readily attacked by chlorine bromine, concentrated sulfuric acid, and nitric acid. These reactions do not decrease the degree of polymerization of the polymers. Aromatic polymers with stiffening groups, such as PPO, polyarylsulfone, polyarylether ketone (PEEK), and polyphenylene sulfide (PPS), are more resistant to attack by corrosives than those with flexibilizing groups. 

Many semicompatible rubbery polymers are added to increase the impact resistance of other polymers, such as PS. Other comminuted resins, such as silicones or polyfluorocarbons, are added to increase the lubricity of other plastics. For example, a hot melt dispersion of polytetrafluoroethylene (ptfe) in polyphenylene sulfide (PPS) is used as a coating for antistick cookware. 

Polyphenylene sulfide (PPS) is a high-melting (290 C), injection-mold-able crystalline polymer with the following repeating unit ... 

High-performance polymers, such as polyphenylene sulfide (PPS) (Ry-ton), have excellent resistance to elevated temperatures, and this property can be enhanced by the incorporation of reinforcing fibers such as graphite fibers. 

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). 

Research Focus Method for preparing intimately mixed polymer blends of nylon-66 and polyphenylene sulfide. 

Sulfar fibers are extruded from polyphenylene sulfide) or PPS by the melt-spinning process. The first PPS polymer was made in 1897 by the Friedel-Crafts reaction of sulfur and benzene. Researchers at Dow Chemical, in the early 1950s, succeeded in producing high-molecular weight linear PPS by means of the Ullmann condensation of alkali metal salts of p-bromothiophenol. 

Liquid Crystal Polymer Polyester - PBT Polyetherimide Polyphenylene Sulfide... 

Many of the procedures used to prepare neutral CP precursors are commonly employed in the polymer industry. Hence, the polymerization methods of Ziegler-Natta, Friedel-Crafts, and nucleophilic displacements yield PA, PP, and polyphenylene sulfide (PPS), respectively. Other methods include Dields-Alder elimination, Wittig, and electrochemical coupling. The procedures used to prepare CPs in this vast arsenal are generally divided into two main categories chemical and electrochemical. 

Very few CPs are produced in bulk quantities. Polyphenylene sulfide, a member of the third generation of polymers, was produced in bulk quantities many years before CPs were established and its dopability was elucidated. Polyethylenedioxythiophene is commercially available as a water-based colloidal dispersion (Baytron P water dispersion), and presumably as dispersible powders. The powders with a conductivity of 5-10 S/cm can be dispersed in thermoplastic polymers and in organic solvents such as xylene. Polyaniline doped with dodecylbenzene sulfonic acid and complexed with zinc dodecylbenzene sulfonate is commercially available as a powder, which can be dispersed in polyolefins. The same polymer doped with p-toluenesulfonic acid is also available as a dispersible powder, Ormecon, and in a predispersed form for solution processing in polar and nonpolar media. Based on Ormecon PANi, there are many commercial products marketed for many different applications. 

Includes acetal, granular fluoropolymers, polyamide-imide, polycarbonate, thermoplastic polyester, polyimide, modified polyphenylene oxide, polyphenylene sulfide, polysulfone, polyetherimide and liquid crystal polymers. 

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. 

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. 

This paper Is concerned primarily with three basic grades of polyphenylene sulfide (1) 40X glass-filled polymer (Grade R-4),... 

Similarly, Figure 6 summarizes the creep behavior of glass-and mineral-filled polyphenylene sulfide under three sets of conditions 24°C/5,000 psi flexural load, 66°C/5,000 psi, and 1210C/3,000 psi. Table III compares the per cent loss In apparent creep modulus at 1,000 hours and at 10,000 hours for each of these conditions using the apparent creep modulus at one hour as a basis. These data Indicate that the creep resistance of the glass- and mineral-filled polymer Is similar to that of the 40% glass-filled resin. 

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