Basf Aktiengesellschaft

Karl-Peter Farwerck

Roger G Klimesch

Lothar Schlemmer

Gerhard Bleckmann

Hilmar Ohlig

J Urgen Hofmann

Axel Sanner

Andreas Deckers

Peter Ittemann

Hans-Helmut Goertz

Albin Berger

Alois Schlarb

Polyolefins are thermomechanically degraded in a twin-screw extruder without a downstream degradation apparatus, at from 300.degree. to 550.degree. C. and from 1 to 100 bar and in average residence times of the reaction mixture of from 0.5 to 10 minutes, by a process in which the pressure in the twin-screw extruder is changed periodically or aperiodically with a fluctuation of from 0.5 to 30 bar. The novel process is particularly suitable for the degradation of polypropylene.

Thermomechanical degradation of polyolefins

In a fiber composite plastic composed of plastic composition and fibers, the fibers have a pronounced fiber length distribution, in particular more than 50% by weight of the fibers have a length outside the range from 0.8.times.L to 1.2.times.L, where L is the mean (weight average) fiber length, and the mean fiber length is greater than the critical fiber length of the plastic composition/fiber system.

Plastic material, and process for the preparation thereof

A mixture of one or more pharmaceutical active compounds and one or more thermoplastic polymers is tabletted by a process in which the mixture is extruded and the still moldable extrudate is pressed to give tablets, between two belts, or a belt and a roller, which make contact in parts, rotate in opposite directions and run parallel along the contact zone, the shape-imparting indentations, which may be present in complementary pairs, being located in both or in only one of the revolving shape-imparting elements.

Continuous preparation of solid pharmaceutical forms

Extrudable pharmaceutical mixtures are tableted by a continuous method in which the mixture is extruded and the still deformable extrudate is pressed between two rollers which are driven in opposite directions and possess depressions opposite one another in the roller shell, the form of these depressions determining the tablet shape.

Continuous method of tableting

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Worms, Germany

Karl-Peter Farwerck