A method of continuously manufacturing a cured membrane includes continuously compounding and mixing a vulcanizable rubber composition in a mixing extruder while continuously removing gasses from the vulcanizable rubber composition during mixing with a vacuum. The vulcanizable rubber composition may be continuously extruded to form an extrudate, which may be continuously calendered to form a green membrane. The green membrane may be continuously cured, such as by a hot air conveyor curing system, to form a cured membrane.

A method of continuously manufacturing a cured membrane includes continuously compounding and mixing a vulcanizable rubber composition in a mixing extruder while continuously removing gasses from the vulcanizable rubber composition during mixing with a vacuum. The vulcanizable rubber composition may be continuously extruded to form an extrudate, which may be continuously calendered to form a green membrane. The green membrane may be continuously cured, such as by a hot air conveyor curing system, to form a cured membrane.

A method of continuously manufacturing a cured membrane includes continuously compounding and mixing a vulcanizable rubber composition in a mixing extruder while continuously removing gasses from the vulcanizable rubber composition during mixing with a vacuum. The vulcanizable rubber composition may be continuously extruded to form an extrudate, which may be continuously calendered to form a green membrane. The green membrane may be continuously cured, such as by a hot air conveyor curing system, to form a cured membrane.

A method is provided for the co-extrusion of a complex rubber profiled element. The method makes it possible to co-extrude a sublayer in a first material and a tread in a second material with at least one insert in a third material inserted in a discontinuity in the sublayer and in the tread. The method includes: a) discontinuous extrusion of the first material, b) discontinuous first profiling of the first material, c) discontinuous extrusion of the second material onto the first material, d) discontinuous profiling of the first and second materials and extrusion of the third material into each discontinuity, and e) final profiling of the first, second and third materials with a longitudinal groove in the profiled element next to each insert of the third material.

A method is provided for the co-extrusion of a complex rubber profiled element. The method makes it possible to co-extrude a sublayer in a first material and a tread in a second material with at least one insert in a third material inserted in a discontinuity in the sublayer and in the tread. The method includes: a) discontinuous extrusion of the first material, b) discontinuous first profiling of the first material, c) discontinuous extrusion of the second material onto the first material, d) discontinuous profiling of the first and second materials and extrusion of the third material into each discontinuity, and e) final profiling of the first, second and third materials with a longitudinal groove in the profiled element next to each insert of the third material.

A multiple screw extruder (50) combines application of vacuum to a vacuum vent (62) positioned between material feed locations (70, 72) of the extruder and use of specially configured extruder screws (58) to extract gases, primarily air, out of the extruder to densify the materials introduced into it and to extract unwanted fluid from material introduced for mixture with molten polymeric material flowing through the extruder. The multiple screw extruder is operationally versatile in that it is capable of carrying out the material densification and fluid extraction processes either separately or simultaneously. Implementation of the disclosed vacuum feed technology provides an increase in rate of extrudate throughput as compared with that achievable by implementation of atmospheric venting (16) in a conventionally configured extruder (10a, 10b).

The invention relates to a method for homogenously incorporating filler into a self-adhesive compound, in particular a thermally crosslinkable self-adhesive compound, based on non-thermoplastic elastomer in a continuously working unit with a filling part and a compounding part. The self-adhesive compound contains at least one solid component, at least one liquid component, and at least one filler, and the method has the following steps: (a) feeding at least part of the at least one solid component, such as the non-thermoplastic elastomer in particular, and optionally part of the at least one liquid component to the filling part; (b) transferring the components of step (a) from the filling part to the compounding part; (c) optionally adding additional solid components or additional parts of the solid components to the compounding part; (d) adding the at least one liquid component to the compounding part if the liquid component was not already added to the filling part in step (a); (e) producing a homogenous self-adhesive compound in the compounding part; and (f) discharging the self-adhesive compound. The invention is characterized in that at least part of the at least one filler is pre-dispersed into at least one dispersion liquid in a separate unit and the dispersion obtained in this manner is added to the compounding part. The method prevents high sheering or frictional energies while introducing the filler into the compounding part of the continuously working unit and thus allows the use of temperature-sensitive components, such as temperature-sensitive chemical crosslinking agents in particular.

Polymeric Materials An injector (14) for injecting liquid formulation into molten polymer includes a conduit (117) having regions (44, 46) which are secured within a wall of an extruder (19). Conduit (117) includes an annular collar (120) having an upwardly facing annular surface (122) which is arranged to bear against part of a sleeve nut (124). Conduit (117) is arranged within a port (125) which includes a screw-threaded wall (126). The sleeve nut (124) includes a cylindrical body (146) having an inwardly facing cylindrical wall which is arranged to define a cylindrical air gap (148) between itself and an outer wall (147) of conduit (117). Region (150) of the sleeve nut is screw-threadedly engaged in wall (126) of the extruder. In use, cool compressed air is introduced into the assembly in the direction of arrow (170) and it flows through the assembly to cool it.

Polymeric Materials An injector (14) for injecting liquid formulation into molten polymer includes a conduit (117) having regions (44, 46) which are secured within a wall of an extruder (19). Conduit (117) includes an annular collar (120) having an upwardly facing annular surface (122) which is arranged to bear against part of a sleeve nut (124). Conduit (117) is arranged within a port (125) which includes a screw-threaded wall (126). The sleeve nut (124) includes a cylindrical body (146) having an inwardly facing cylindrical wall which is arranged to define a cylindrical air gap (148) between itself and an outer wall (147) of conduit (117). Region (150) of the sleeve nut is screw-threadedly engaged in wall (126) of the extruder. In use, cool compressed air is introduced into the assembly in the direction of arrow (170) and it flows through the assembly to cool it.

A method of continuously manufacturing a cured membrane includes continuously compounding and mixing a vulcanizable rubber composition in a mixing extruder while continuously removing gasses from the vulcanizable rubber composition during mixing with a vacuum. The vulcanizable rubber composition may be continuously extruded to form an extrudate, which may be continuously calendered to form a green membrane. The green membrane may be continuously cured, such as by a hot air conveyor curing system, to form a cured membrane.