Excavations in Guatemala have shown that already in the 3rd century, the Maya knew rubber as a material. Since the 18th century, more and more applications are described. Invention of the vulcanization process by Charles Goodyear in 1839 enabled stable elastic properties both in cold and hot conditions, and thus the breakthrough to technical applications as well. At the beginning of the twentieth century, German chemists succeeded in producing synthetic rubbers.
Traditionally, elastomers have been produced on internal mixers or rolling mills. These established processes offer advantages such as maximum flexibility, precise offline dosing of even the smallest formulation proportions, as well as variable dwell and mixing times. However, limitations such as high specific energies, interim storage times and also property fluctuations between individual batches, have underlined the advantages of continuous processing in compounding machinery. These typically include uniform process conditions, narrow residence time distribution, integration of process steps and improved product quality consistency. The BUSS rubber compounding technology and especially the BUSS Kneader can offer even more advantages with its precise temperature control, the ability to mix high proportions of filler in an excellent and yet gentle way, and also the ability to inject liquid ingredients such as softener oils or reagents directly into the process zone at the optimal position.
The widespread and highly successful use of the BUSS Kneader for silicone and fluoroelastomers has been known for decades. Recently, a wide range of other application fields has been added to the BUSS compounding technology. The integration of process steps, the expansion of requirement profiles and the use of alternative recipe components play the main roles.