The set of mechanical properties and the inherent durability of each raw polymer being generally unsuitable as it is for engineering applications, it is essential to upgrade and customize the raw thermoplastics by compounding before their use to satisfy the requirements of customers and applications.
Among the most known reinforcement materials, glass fibres are broadly used under various forms, for example chopped ones dispersed into the matrix or continuous ones well ordered to customize the reinforcement. Carbon, and aramid fibres are also used for more sophisticated applications. Nano-fillers are emerging in automotive industry and very promising.
Durability must be considered according to the real environment because of the specificity of each protective agent.
Unfortunately other characteristics can also be deteriorated by these additives and it is necessary to carefully study the better balance between all the properties
The producer brings certain improvements but others are implemented by compounders or by the converter himself.