DURABILITY AND RELIABILITY OF PLASTIC PRODUCTS

The durability and reliability of a polymer-based product are determined by a number of factors inherent to the material itself (for example, crystallinity, average molecular weight), to its processing (for example, shear-induced degradation, process-induced thermal degradation), and to its service environment (such as, temperature, humidity and the presence of vibrations) [11]- 

1 Intimate knowledge of the application. It is clear that the first step in determining durability is to spedfy which performance criteria are vital to the products function. For example, in an aircraft application such as a structural wing part, performance requirements may be such as retaining dimensional stability and yield stress for 12,000 supersonic hours xmder cyclic loads and temperatures up to 175 C. 

An understanding and quantification of the mechanisms of ageing and their relation to the intrinsic properties of the material. 

Develop time- and geometry-based scaling techniques to relate laboratory tests to the real performance of a structure, and accelerated test methods for simulating long-term ageing. 

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