Rubber processing

Raw rubber as received from the manufacturer(Indonesia, Thailand, Malaysia, Myanmar, Vietnam, India, Sri Lanka, China), or from the plantation in the case of natural rubber, has few uses as such. It has to be mixed with various compounding ingredients, shaped and vulcanized to give a usable end product. These three components, mixing, shaping and curing, together, called rubber processing.

Mixing is central to rubber processing. If the base compound is inadequately mixed, problems cascade down through the subsequent processes or shaping and curing in to the end product such as rubber Hot water bottle. There are 3 general shaping process: extrusion, calendaring and molding(compression), transfer or injection type.

Rubber is a difficult material to process because it has both viscous and elastic properties. But even more than this, because of the infinite variety of possible compounds that can be prepared from any grade of rubber. It is difficult to predict mixing, molding or extrusion behavior of a compound base on the properties of the raw rubber alone. Depend on the type and quantity of carbon black, plasticizer, other fillers, etc. The resulting compound is formulated to meet end-application requirements not merely to easy process. The processing plant has to adjust its process to suit the compound, not the other way around. However, it is of no value to present the factory with a compound impossible to mixing or processing. Therefore, it has to be integration between the compound, process and product, involving extensive cooperation between compounder, mixer and processor.