Polyphenylene sulphide properties

The range of blends now available comprises a broad spectrum of materials superior in many respects, particularly heat deformation resistance, to the general purpose thermoplastics but at a lower price than the more heat-resistant materials such as the polycarbonates, polyphenylene sulphides and polysulphones. At the present time the materials that come closest to them in properties are the ABS/ polycarbonate blends. Some typical properties are given in Table 21.1. 

Polyphenylene sulphide (PPS) (e.g. Ryton ) is a highly crystalline polymer with a melting point of 290 °C. It combines good mechanical properties with very high thermal and chemical resistance it is, moreover, self-extinguishing. It is, i.a., used as protective coating on metal surfaces. 

The theory has shown that an improvement of some 50% in mechanical properties should be produced by increasing fiber length from 0.3 mm to 2 mm. Several producers and specialist compounders of TPs have long fiber technology using nylons, polypropylenes, TP polyesters, and polyphenylene sulphide (PPS). 

Polyphenylenes The polyphenylene-based thermoplastics family includes polyphenylene ether (PPE), polyphenylene oxide (PPO), and polyphenylene sulphide (PPS). They have been one of the most successful groups introduced in the medium/higher range of cost/performance, with good heat stability and particularly good flammability properties. 

The Ryton polyphenylene sulphide compounds are formulated for the encapsulation of semiconductors and discrete components and are particularly suited to this application because of their excellent thermal stability, resistance to chemical environments, flame retardancy and good electrical properties over a wide temperature range. In order to be suitable for the encapsulation of microcircuits and transistors the material must have good flow during moulding, good dimensional stability, low levels of impurities and low moisture absorption characteristics. 

Polyphenylene sulphides are a range of compounds offering a unique combination of mouldability, good electrical properties, solvent and... 

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