Characterization and testing of plastics

Plastics have become essential materials for both everyday use and high-performance applications such as aeronautics and electronics, to name but two examples. The tonnages used are impressive (270 million tonnes in 2012), intermediate between those of steel and aluminum, with a growth rate higher than that of traditional materials. The plastics industry is still in its infancy, and requires a great deal of sophisticated characterization in addition to routine control requirements. The characterization and control of plastic materials are crucial to the quality of parts produced by processors or purchased by end-users. The economic implications are increasingly important, especially as sources of supply are diversifying to include many countries undergoing rapid industrial development.

Traditional testing has evolved towards more sophisticated, more diversified and faster techniques, enabling products to be tested directly on production lines. For example, the automated control of presses and extruders requires real-time results, enabling control software to react almost immediately to optimize manufacturing quality and costs, despite increasingly stringent specifications. For the design of parts and systems, there is a huge need to collect the parameters required for the operation of design, modeling and simulation software, and to assess durability over the long term (up to 50 years and more) under more or less difficult conditions.

The implications are technical, economic, commercial and environmental, in order to meet the varied needs of the different players - producers, processors, designers, specifiers, molders, recyclers, buyers and users of plastic parts.

Characterization and control, like all other industrial operations, must pursue defined goals so that their cost does not unnecessarily burden production costs.

Technically, the tests carried out are based on the specific characteristics of the plastics and the practical results expected. Scientific research is beyond the scope of this article.