Educational Tutorial Sequence
The first step to creating a rubber compound is to gather all the ingredients and then measure by weight. Common ingredients include: Rubber polymer, Carbon Black, Oils, Zinc Oxide, Sulfur, Methyl-Ziamate, and Stearic Acid. All ingredients are now measured and need to be mixed together.   Ingredients being mixed in a Brabender internal mixer.
The operator removes the mixed rubber from the internal mixer. The rubber is then put through a two-roll mill to create a sheet and take heat out of the rubber to prevent pre-mature curing of the material.
A small piece of the rubber is then put into a specialized piece of equipment called a Moving Die Rheometer, which will evaluate the curing characteristics or rheology of the rubber. The curing characteristics are then fed to a computer, where a data table and cure curve is displayed. From this information the molding technician will know exactly how long to cure or "bake" the rubber to create a useful rubber product.
For laboratory work, test slabs are molded to evaluate the recipes physical and dynamic properties. Here the mixed rubber is put into a test slab mold and cured according to the data obtained from the Moving Die Rheometer. This fully cured test slab will then be used to create test specimens by die-cutting various shapes from the slab and using standardized tests to evaluate the physical and dynamic properties of the rubber recipe.