Preparation of thermoplastics

US5852113A · kind A · utility

Assignee

• BASF SE

Inventors

• Norbert Güntherberg · Speyer, DE
• Jurgen Hofmann · Spalt, DE
• Elmar Mailahn · Worms, DE
• Hilmar Ohlig · Kaiserslautern, DE
• Sven Grabowski · Ludwigshafen, DE
• Bernhard Czauderna · Hirschberg, DE
• Klaus Bus · Kaiserslautern, DE

Key dates

• Filing date: Mar 22, 1996
• Grant date: Dec 22, 1998
• Expiry date: Mar 22, 2016

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29K2096/02
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Toughened thermoplastics are prepared by mixing a water-moist elastomer component A containing up to 60% by weight of residual water with a thermoplastic polymer B and further polymers C and additives D in an extruder with mechanical dewatering of the elastomer component A, by a process in which the components A, B, C and D are fed to a twin-screw extruder which has corotating screws and essentially comprises, in the transport direction, PA1 at least one metering section in which the elastomer component A is fed to the extruder by a metering means, PA1 at least one squeeze section which serves for dewatering the component A and contains at least one retarding element and in each case at least one associated dewatering orifice, PA1 at least one section in which the thermoplastic polymer B is introduced as a melt into the extruder, PA1 at least one section provided with mixing, kneading or other plasticating elements or combinations of these elements, PA1 at least one devolatilization section which is provided with at least one devolatilization orifice and in which the residual water is removed as steam, and PA1 a discharge zone, the water emerging from the dewatering orifices being …