摘要:
The invention relates to polycarbonates with extremely low residual levels of volatile constituents and thermal degradation products, and also improved optical properties, especially Yellowness Index (YI) and good thermal stability, from solvent-containing polymer melts. The invention further relates to an apparatus and a process for preparing these polycarbonates with the aid of a devolatilizing extruder with at least three devolatilizing zones, and zones for introducing entraining agent into dispersion are present upstream of at least three devolatilizing zones.
摘要:
The invention relates to polycarbonates with extremely low residual levels of volatile constituents and thermal degradation products, and also improved optical properties, especially Yellowness Index (YI) and good thermal stability, from solvent-containing polymer melts. The invention further relates to an apparatus and a process for preparing these polycarbonates with the aid of a devolatilizing extruder with at least three devolatilizing zones, and zones for introducing entraining agent into dispersion are present upstream of at least three devolatilizing zones.
摘要:
The invention relates to novel screw feed elements for multi-shaft screw feed machines having screw feed profiles rotating in the same direction in pairs and precisely abrading in pairs, to the use of the screw elements in multi-shaft screw feeding machines and to a method for extrusion of viscoelastic masses.
摘要:
The invention relates to a device for dispersing gas into a liquid. The devise has a number n of successive zones Z1, Z2, . . . , Zn having static mixing elements, wherein each zone Zi has a length Li and an effective diameter Di. The mechanical energy input Et, which is standardised to the particular ratio Li/Di and acts on the gas/liquid mixture, increases from zone to zone in the flow direction. In this connection n is a whole number greater than or equal to 3 and i is an index which runs through the whole numbers from 1 to the number n of zones. The invention further relates to a method for dispersing gas into a liquid using the device according to the invention.
摘要:
The invention relates to novel screw feed elements for multi-shaft screw feed machines having screw feed profiles rotating in the same direction in pairs and precisely abrading in pairs, to the use of the screw elements in multi-shaft screw feeding machines and to a method for extrusion of viscoelastic masses.