To develop a final recipe that meets a given set of specifications, compounders have a wide variety of "ingredients" at their disposal. These ingredients fall into nine overall categories.
Elastomers
The basic component of all recipes, elastomers can take the form of a single polymer, or they can be used in various combinations.
Processing Aids
These aids modify the compound during mixing and processing or during the extrusion or molding process.
Vulcanizing Agents
Vulcanization, or chemical cross-linking, is necessary to improve a compound's physical properties and to ensure that it will remain in its final extruded or molded shape.
Accelerators
Accelerators increase the rate of vulcanization, and in many instances, also improve the final product's physical properties.
Accelerator Activators
These activators work with accelerators to reduce vulcanization time and improve a compound's final characteristics.
Age-Resistors
Materials such as antioxidants and antiozonants serve to slow down the deterioration of rubber products that can occur as a result of exposure to light, heat, oxygen, radiation, ozone, etc.
Fillers
Fillers are used to reduce the costs, reinforce or alter physical properties or facilitate final processing.
Softeners
Softeners can be used to promote polymer elasticity, aid in the mixing process, increase tack or extend/replace a portion of a polymer's hydrocarbon content.
Miscellaneous Ingredients
The category of ingredient includes colors, blowing agents, odorants, retarders, abrasives and dusting agents, and is normally used to impart very specific characteristics to a compound.
