Polyphenylene sulfides mechanical properties

As a further comparison, the flexural modulus of glass-filled polyphenylene sulfide at 450° F is about 10 times that of unfilled polytetra-fiuoroethylene at room temperature. These data illustrate the outstanding retention of stiffness of this material at elevated temperatures. The heat-deflection temperature of polyphenylene sulfide containing 40% glass fibers is greater than 425°F, accounting for the excellent retention of mechanical properties at elevated temperatures. 

Ryton Polyphenylene Sulfide is a new commercial plastic which is characterized by good thermal stability, retention of mechanical properties at elevated temperatures, excellent chemical resistance, a high level of mechanical properties, and an affinity for a variety of fillers. It is produced from sodium sulfide and dichlorobenzene. Its unusual combination of properties suggests applications in a variety of molded parts such as non-lubricated bearings, seals, pistons, impellers, pump vanes, and electronic components. Tough coatings of polyphenylene sulfide can be applied to metals or ceramics by a variety of techniques and are used as protective, corrosion-resistant coatings in the chemical and petroleum industries. Incorporation of small amounts of polytetrafluoroethylene provides excellent non-stick properties in both cookware and industrial applications. 

Polyphenylene sulfide also retains good mechanical properties at elevated temperatures, as illustrated in the plot of flexural modulus (a... 

Blends of PET/HDPE have been treated previously in the literature [157, 158]. These are immiscible, but the addition of compatibilizers improves the mechanical properties of the blend, such as styrene-ethylene/butylene-styrene (SEBS) and ethylene propylene diene monomer (EPDM) [157], MAH [158], Poly(ethylene-stat-glycidyl metha-crylate)-graft-poly(acrilonitrile-stat-styrene) (EGMA), poly (ethylene acrylic acid), and maleated copolymers of SEBS, HDPE, ethylene-propylene copolymer (EP). The addition of compatibilizers modifies the rheological properties of blends of PET with HDPE, in such a way that increases in viscosity are observed as the component interactions augment. Changes in crystallization of PET were evaluated in blends with Polyphenylene sulfide (PPS), PMMA, HDPE aromatic polyamides, and copolyesters [159]. 

Thermoplastic matrices, is particularly attractive for automotive applications PP, for example, is economical, it can be processed quickly and can provide much better mechanical properties such as impact resistance, (i.e., bumpers, body panels [11]). PA are successfully applied in both under hood (i.e., inlet manifolds, radiator fans) and interiors (instrument panels, doors, front-end structures). For better temperature performance and mechanical properties, in some special application areas (motor racing sector, gearbox parts), polyether ether ketone and polyphenylene sulfide ( high performance thermoplastics ) are also used as matrices. 

Engineering thermoplastic resins (ETP) are those whose set of properties (mechanical, thermal, chemical) allows them to be used in engineering applications. They are more expensive than commodity thermoplastics and generally include polyamides (PA), polycarbonate (PC), linear polyesters such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), polyphenylene ether (PPE) and polyoxymethylene (POM). Specialty resins show more specialized performance, often in terms of a continuous service temperature of 200°C or more and are significantly more expensive than engineering resins. This family include fluoropolymers, liquid crystal polymers (LCP), polyphenylene sulfide (PPS), aromatic polyamides (PARA), polysulfones (P ), polyimides and polyetherimides. 

Polyphenylene sulfide opens up new possibilities in aerospace, chemicals, electronic, food, and transportation applications [86], Thermoformed polyphenylene sulfide, in addition to its excellent mechanical properties (Table 3.2), can tolerate high tanpera-tures for prolonged periods of time. Thus, umeinforced polyphenylene sulfide has a thermal index of 186°C, and glass fiber-reinforced polyphenylene sulfide has a thermal index of 220°C. 

There are other plastics used in addition to those listed in Table (S-14. One example is a polyphenylene sulfide film that is biaxially oriented (BOPPS), with 40 percent crystallinity. It is roughly equivalent to a polyester film in its mechanical properties. This self-extinguishing PPS has a long-term heat resistance per UL 746 B of 160°C (320°F) for mechanical and 180°C (356°F) for electrical resistance. 

TABLE 3-86. PHYSICAL AND MECHANICAL PROPERTIES OF POLYPHENYLENE SULFIDE... 

Polyphenylene sulfide, however, emits corrosive, sulfurous gases beginning at 150 °C, which limits its upper service temperature depending on the application. This temperature is far below the maximum service temperature of 260 that applies to its mechanical properties. 

The second way is to synthesize block copolymers. Terada et al. [173,174] demonstrated that these polymers of which at least one contains an ammonium group (Fig. 5.22) exhibited better mechanical properties than the traditional copolymers. Hwang and Ohya [175] prepared an AEM, polysulfone/polyphenylene sulfide sulfone (PS/PPSS), by using block copolymers. The synthesis was realized in four steps. The resistance of the membranes was between 0.9 and 1.4 i2/cm, depending on the degree of quatemization, and the lEC was between 1.46 and 3.7 X 10 equiv./g. 

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