abstract |
A method of making silica loaded elastomer masterbatches or compounded productive elastomer stocks with or without the simultaneous extrusion of component profiles is provided. A twin-screw extruder is used to mix the elastomeric stock in multiple mixing zones at controlled temperatures in which a concurrent chemical reaction takes place between the silica coupler, the silica, and/or the diene based elastomer. Silica, elastomer, silica coupler, and other ingredients are fed into the twin screw extruder continuously through precise loss-in-weight or volumetric feeders. Chemical reactions(s) in the elastomer/silica based composition take place within the twin-screw extruder while the composition is mixing. The product is forced through a profile die mounted at the exit of the extruder and formed into the shape of the desired component. The maximum rate of mixing tends to be a function of the heat transfer efficiency, the conveying capacity of the screws, and the mechanical strength of the extruder. |