Cost saving is a universal headache for all the manufacturers and, of course rubber ones are concerned, the more so as rubber goods are mass-produced and must vie with plastics which are easy to process. There are several routes such as filling with cheap fillers, the best known or on the opposite, using expensive but performing fillers.
This paper is going to deal with cheap fillers that are numerous and in addition can bring some specific properties but also some degradation of mechanical, chemical and electrical properties if their amount is too high or if the formulation is unsuitable. Some of these fillers are very widespread such as calcium carbonates or talcs but others are more specific such as ATH used for halogen-free FR grades or micas used to reduce the gas permeability or to improve the dielectric properties.
The cost variations of the vulcanizates are very different if considered per volume or per weight. In the first case, filling can lead to cost increase instead of cost saving.