| 摘要 |
The invention relates to a method for preparing decontaminated natural rubber. The method is characterised in that it includes a decontamination step in which wet natural rubber coagulum is passed through a system comprising an extruder and a filter installed at the extruder outlet, said extruder having an axially symmetrical grooved sheath provided with grooves in its thickness that open at the inner surface of the sheath. The method is also characterised in that the sheath is such that, in any plane perpendicular to the axis of the sheath, with R (expressed in mm) being the distance between the centre of the sheath and the inner surface of the sheath: a. the ratio (total length of the groove openings, expressed in mm)/(2πR), denoted A, is at least equal to 0.25 and at most equal to 0.9; b. the ratio (number of grooves/2R), denoted B, is greater than or equal to 0.1; c. the ratio (depth of grooves expressed in mm)/(2R), denoted C, is greater than 0.02; and d. the plane that passes through the two bottom edges forms, together with each plane passing through a bottom edge and an intersection edge, defining a side face, an angle δ at least equal to 60° and at most equal to 90°. |
