Polyarylsulfone heat resistant

The reaction of bis(4-chlorophenyl)sulfone with the anhydrous dialkali salt of a,a -bis(4-hydroxyphenyl)-p-diisopropyl benzene, which is dissolved in an aprotic solvent, leads to a new heat-resistant polyarylsulfone. A general discussion of monomer and polymer preparation is given as well as physical and mechanical properties of this polyarylsulfone. 

Jn recent years, there has been a considerable amount of interest in high-molecular-weight polyarylsulfone polymers (1-3). These polymeric materials possess heat-deflection temperatures of 165°-260°C plus excellent thermal stability at the high processing temperatures required. This paper deals with the synthesis and the physical and mechanical properties of a new heat-resistant polyarylsulfone. This new polyarylsulfone thermoplastic exhibits a significant reduction in apparent (melt) viscosity with only a slight reduction in heat deflection temperature when compared with the polyarylsulfone based on bis(4-chlorophenyl)sulfone and 2,2-bis (4-hydroxyphenyl) propane. 

Polysulfone It is a high performance amorphous plastic that is tough, highly heat resistant, strong and stiff. Products are transparent and slightly clouded amber in color. Material exhibits notch sensitivity and is attacked by ketones, esters, and aromatic hydrocarbons. Other similar types in this group include polyethersulfone, polyphenyl-sulfone, and polyarylsulfone. Use includes medical equipment, solar-heating applications and other performance applications where flame retardance, autoclavability and transparency are needed. 

The polyarylsulfone thermoplastic exhibits essentially the same heat resistance of the polyarylstdfone based on bis-(4-chlorophenyl)sulfone and 2,2-bis(4-hydroxyphenyl)pro-pane, along with the added plus of a lower melt viscosity at equivalent processing temperatures. The flow improvement is demonstrated by comparison with Brabender data, injection-molding conditions, and melt-viscosity data. 

Polyarylsulfone (PAS) thermoplastics have relatively low melt-processing temperatures, considering their high mechanical properties. For one thing, they are hydrolytically stable. They have a heat-distortion temperature at least 204°C (400 F) at 1,820 kPa (264 psi), tensile strengths to 124 MPa (18,000 psi) or better, and a flexural modulus up to 1.17 X 10 psi. Under stress they are highly resistant to mineral acids and alkali and salt solutions. Their applications are in electrical and electronic items, frozen-food packaging, and aircraft interiors. 

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