Raw Materials for rubber

Rubbers are formulated products with an average polymer content of only 50%, which is low compared to plastics, which are essentially composed of polymer (around 90% if we exclude PVC). A rubber object therefore contains various ingredients, the main ones being :

• one or more natural rubber or synthetic rubber polymers;

• with a more or less marked reinforcing effect;

• plasticizers, whether of petroleum or vegetable origin;

• a sulfur- or peroxide-based vulcanization system;

• a protection system against ageing, whether thermomechanical or otherwise;

• of various products according to specification requirements.

The mixing process, which distributes and disperses these different elements, has an influence on the properties and performance of rubber articles.

This article deals only with vulcanizable rubbers and not with thermoplastic rubbers. To avoid any risk of confusion, the term "rubber" is reserved for formulated products and the term "elastomers" is reserved for polymers used in formulations.

As is customary in the industry, unless otherwise specified, the percentages given are by mass.