UNIT FOR THE PRODUCTION OF RUBBER-POLYOLEFIN COMPOSITIONS Russian patent published in 2023 - IPC B29C48/395 

FIELD: polymer production.

SUBSTANCE: processing polymeric materials by pressure, and more specifically installations for producing composite thermoplastic materials based on the products of processing of shock-absorbing tires and rubber products (granules and powders) and primary and/or secondary polyolefins. The installation for the production of rubber-polyolefin compositions includes an extruder mounted on a frame and a static mixer connected by means of a transition unit. The extruder has a heated prefabricated cylindrical body, in which a screw is installed, having a rod configuration that changes along its length and cutting coils. The shape of the screw determines the division of the internal volume of the extruder into four consecutive process zones. The loading and heating zone, in which the screw is made single-thread, the screw rod has a constant diameter. The melting zone, in which the screw is made single-thread, the screw rod expands conically towards the unloading. The zone of intensive mixing and degassing, at the beginning and at the end of the zone, annular grooves are made in the screw, opposite these grooves, mixing radial pins are fixed in the body. The zone of increase in the melt flow rate, in which the screw is made double-threaded, the screw rod conically expands towards the unloading, the depth of the screw thread evenly decreases in the direction of material movement. The screw pitch of this zone is larger than the pitch of the intensive mixing and degassing zone. In the transition unit there is a conical end screw of the screw. The inner surface of the body of the transition unit has the shape of a cone tapering towards the unloading.

EFFECT: possibility of obtaining rubber-polyolefin compositions with a rubber crumb content of up to 75-85 %wt while maintaining the structure of rubber crumb in a two-phase (rubber crumb and polymer melt) composition.

1 cl, 2 dwg