Thermal end use properties

The properties which determine the environmental behaviour of polymers after processing into final products may be divided into three categories the thermal end use properties, the flammability, and the properties determining the resistance of polymers to decay in liquids. 

By heat stability is exclusively understood the stability (or retention) of properties (weight, strength, insulating capacity, etc.) under the influence of heat. The melting point or the decomposition temperature invariably forms the upper limit the use temperature may be appreciably lower. 

All intrinsic properties are influenced by temperature these relationships have been treated in the relevant chapters of this book. Especially the influence of temperature on the 

The heat distortion test is similar to a creep test, except that the temperature is increased at a uniform rate rather than being kept constant. At the softening or heat distortion temperature the polymer begins to deform at a rapid rate over a narrow temperature interval. In the heat distortion test ISO-HDT-A or ISO-HDT-B a standard bar is loaded 

Polymer Ultimate end-use temperature range in 200 h (°C) Ultimate end-use temperature range in 1000 days (°C) 

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