Polyethersulfone mechanical properties

The tensile and flexural properties as well as resistance to cracking in chemical environments can be substantially enhanced by the addition of fibrous reinforcements such as chopped glass fiber. Mechanical properties at room temperature for glass fiber-reinforced polysulfone and polyethersulfone are shown in Table 5. 

Several companies have marketed polyarylates under the trade names U-polymer (Unitika of Japan), Arylef (Solvay of Belgium), Ardel (Union Carbide), and Arylon (Du Pont). These are noncrystallizing copolymers of mixed phthalic acids with a bisphenol and have repeat units of the type shown above. They are melt processable with Tg and heat distortion temperatures in the range of 150-200°C and have similar mechanical properties to polycarbonate and polyethersulfones (see later). 

Thermoplastics are sometimes added to epoxy resins. Thermoplastic-modified epoxy resins [43,44] based on tri- and difunctional epoxy resins cured with DDS and blended with polyethersulfone form the basis for the matrix material in a composite used for the Boeing 777 aircraft. The incorporation of the thermoplastic helps the processing characteristics and also improves the mechanical properties, notably the toughness. The thermoplastic is able to phase separate from the epoxy phase and acts as a reinforcement for the epoxy matrix, enhancing its high temperature properties. The maximum use temperatures of all these resins will typically be 30 to 50 degrees lower than the cited Eg, assuming the same cure schedule. 

Weber and Giintherberg (1999) have prepared compatibilized blends of PA and polyethersulfone in the presence of S-MA-(N-phenylmaleimide) terpolymer. In the examples, the PA was derived either from hexamethylenediamine-isophthalic acid or from hexamethylenediamine-caprolactam-terephthalic acid. Blends comprising PA, an amine-terminated polyethersulfone, and S-MA-(N-phenylmaleimide) terpolymer prepared in a Haake mixer were characterized using mechanical properties testing, selective solvent extraction, DSC, and Vicat B test. Blends optionally contained phenoxy resin. 

TABLE 13.5 Typical Physical and Mechanical Properties of Glass-Fiber-Reinforced (GR) Polysulfone, Polyethersulfone, and Polyphenylsulfone... 

The effect of temperature on tensile stress-strain behavior of PSF is depicted in Figure 4. The resin continues to exhibit useful mechanical properties at temperatures up to 160°C imder prolonged or repeated thermal exposure. This temperature Umit is extended to about 180°C in PES and PPSF. The tensile and flexin-al properties as well as resistance to cracking in chemical environments can be substantially enhanced by the addition of fibrous reinforcements such as chopped glass fiber. Mechanical properties at room temperatme for glass fiber-reinforced polysulfone, polyethersulfone, and polyphenylsulfone are shown in Table 5. 

Crystallinity is key to the development of mechanical properties and good chemical resistance. It is what differentiates PARK from cheaper, but higher Tg, amorphous materials such as polyethersulfones and polyetherimides. 

Chung, T. S., J. J. Qin, J. Gu, Effect of Shear Rate Within die Spinneret on Morphology, Separation Performance and Mechanical Properties of Ultrafiltration Polyethersulfone Hollow Fiber Membranes. Chemical Engineering Science, 2000, 55(6), 1077-1091. 

Sun H., Sur G. S., and Mark J. E., Microcellular foams from polyethersulfone and polyphe-nylsulfone-preparation and mechanical properties. Europe Polymer Journal 2002, 38, 2373-2381. 

Amorphous materials are random entanglements of pol5mer chains, known for very good mechanical properties (strength, stifi iess) and dimensional performance. Amorphous polymers include ABS, polycarbonate, PPO/PPE, polyphenylene sulfone, polyethersulfone, polysulfone and polyetherimide. 

T.S. Chung, J.J. Qin, and 1. Gu, Effect of shearrate within the spinneret on morphology, separation performance and mechanical properties of ultrafiltration polyethersulfone hoUow fiber membranes, Chemical Engineering Science 55 (2000) 1077. 

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