METHOD AND APPARATUS FOR MIXING DEVOLATIZING AND EXTRUDING

• Main Author: BRYCE MAXWELL
• Format: Patent
• Language: English
• Published: 10.11.1971
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

1,253,412. Centripetal extruders. B. MAXWELL. 10 Jan., 1969 [10 Jan., 1968], No 1678/69. Heading B5A. A centripetal melt extruder comprises a rotor 1b and stator 8b, provided with heating and cooling means 5b and 4b respectively, and a vent 11b for the release of volatiles, with or without vacuum assistance, or the addition of such materials as fillers, foaming agents, grafting agents and other shear polymer additives or alloying elements. As shown, the gap width between stator and rotor is increased in the zone surrounding die orifice 15b, such increase preventing material accumulation in peripheral feed zone 7b. Vents may be provided in either or both the rotor and stator. In the embodiment of Fig. 1 (not shown), the shear gap width is constant, in that of Fig. 3 (not shown), the rotor and stator are contoured to prevent material flow into conduit (13c) via manifold (12c) and vent (11c).