摘要:
The invention relates to a method for carrying out polycondensation reactions, according to which the polycondensation of a monomeric starting material is carried out with external supply of heat in a reactor combination which has at least two stages and is composed of a pre-reactor and a high-viscosity reactor, where the low-molecular-weight elimination products produced are removed by evaporation. In the pre-reactor, the reaction product is concentrated to give a high-viscosity preliminary product. The high-viscosity preliminary product is then fed to the high-viscosity reactor, in which it reacts to completion with simultaneous introduction of thermal and mechanical energy and with a residence time of from 20 s to 60 min to give a polycondensation product.
摘要:
Polysuccinimide and polyaspartic acid are prepared by polymerizing maleic anhydride, ammonia and water or maleic acid derivatives or fumaric acid derivatives in bulk or dissolved in solvents in a continuous kneading reactor. The polysuccinimide formed can be converted into polyaspartic acid and polyaspartate salts by hydrolysis.
摘要:
The invention relates to novel screw elements for multi-screw extruders with screw profiles co-rotating in pairs and being fully self-wiping in pairs, to the use of the screw elements in multi-screw extruders and to a process for extruding plastic compositions.
摘要:
A continuous process for the production of an elastomer-modified thermoplastic is disclosed. The process entails (i) obtaining graft elastomer (D) having residual moisture content of 1 to 50 wt. %, particularly 5 to 50 wt. %, particularly preferably 10 to 40 wt. %, (ii) introducing (D) and thermoplastic resin (B) through an inlet to a reactor operating under conditions calculated to melt (D) and (B) and to remove organic volatile components C) to produce a molten blend, the reactor being equipped with a plurality of kneading bars, that convey a portion of the molten blend towards the reactor inlet.
摘要:
A continuous process for the production of an elastomer-modified thermoplastic is disclosed. The process entails (i) obtaining graft elastomer (D) having residual moisture content of 1 to 50 wt. %, particularly 5 to 50 wt. %, particularly preferably 10 to 40 wt. %, (ii) introducing (D) and thermoplastic resin (B) through an inlet to a reactor operating under conditions calculated to melt (D) and (B) and to remove organic volatile components C) to produce a molten blend, the reactor being equipped with a plurality of kneading bars, that convey a portion of the molten blend towards the reactor inlet.
摘要:
The invention relates to a process for extruding plastic compositions, in particular polymer melts and mixtures of polymer melts, above all thermoplastics and elastomers, particularly preferably polycarbonate and polycarbonate blends, also with the incorporation of other substances such as for example solids, liquids, gases or other polymers or other polymer blends with improved optical characteristics, with the assistance of a multi-screw extruder with specific screw geometries.
摘要:
The invention relates to a process for extruding plastic compositions. The process in particular relates to the conveying, kneading and/or mixing of plastic compositions, in particular of polymer melts and mixtures of polymer melts, above all thermoplastics and elastomers, particularly preferably polycarbonate and polycarbonate blends, also with the incorporation of other substances such as for example solids, liquids, gases or other polymers or other polymer blends.
摘要:
The invention relates to a process for extruding plastic compositions, in particular polymer melts and mixtures of polymer melts, above all thermoplastics and elastomers, particularly preferably polycarbonate and polycarbonate blends, also with the incorporation of other substances such as for example solids, liquids, gases or other polymers or other polymer blends with improved optical characteristics, with the assistance of a multi-screw extruder with specific screw geometries.
摘要:
The present invention relates to screw elements with novel, tightly intermeshing, self-cleaning, co-rotating screw profiles for multishaft screw machines with pairs of co-rotating and fully abrading screw shafts, to the use of these screw elements in multishaft screw machines and to a method of generating these screw elements.