摘要:
The invention is directed to an extruder (10), particularly for extruding a synthetic rubber product, which comprises a barrel (24), one or several extruder elements (12, 14), particularly one or several extruder screws and/or a kneader elements (14), arranged inside the barrel (24) for conveying the product, optionally an inlet port for feeding a stripping agent into the barrel (24) and an outlet port for removing volatile compounds from the product and, where applicable, the stripping agent. According to the invention a perforated die plate (26) is fixed to the barrel (24) in flow direction before the outlet port. Since the die plate (26) is not fixed to the extruder elements (12, 14) but to the barrel (24) a circumferential clearance between the die plate (26) and the barrel (24) is prevented so that no extruded material is passing the die plate (26) radially outside. Parts of the extruded material comprising a low surface area to volume ratio are prevented so that the evaporation of volatile compounds is facilitated.
摘要:
The invention is directed to an extruder (10), particularly for extruding a synthetic rubber product, which comprises a barrel (24), one or several extruder elements (12, 14), particularly one or several extruder screws and/or a kneader elements (14), arranged inside the barrel (24) for conveying the product, optionally an inlet port for feeding a stripping agent into the barrel (24) and an outlet port for removing volatile compounds from the product and, where applicable, the stripping agent. According to the invention a perforated die plate (26) is fixed to the barrel (24) in flow direction before the outlet port. Since the die plate (26) is not fixed to the extruder elements (12, 14) but to the barrel (24) a circumferential clearance between the die plate (26) and the barrel (24) is prevented so that no extruded material is passing the die plate (26) radially outside. Parts of the extruded material comprising a low surface area to volume ratio are prevented so that the evaporation of volatile compounds is facilitated.
摘要:
The present invention relates to a reactor (10) and a process for continuous polymerization, where the reactor (10) has an essentially tubular reactor housing (16). The reactor housing (16) has a drive (38) which runs along the geometric central axis (12) in the flow direction (22) and is configured as a central shaft. A rotatably arranged scraper or wiper (36) is provided within the reactor housing (16); the scraper or wiper (36) has at least one scraper or wiper blade (42) to run along an interior side (44) of the reactor housing (16). The rotational movement of the scraper or wiper (36) results in radial mixing of a stream within the reactor housing (16) which dominates gravity effects and, by virtue of shaping of the scrapers or wipers, optionally makes plug flow or backflow within the reactor (10) possible. This allows the reaction conditions in the axial direction of the reactor housing (16) to be predicted and individually suitable reaction conditions to be set and controlled along the reactor housing, so that, in particular, a desired molecular weight distribution can be set.
摘要:
The present invention relates to a reactor (10) and a process for continuous polymerization, where the reactor (10) has an essentially tubular reactor housing (16). The reactor housing (16) has a drive (38) which runs along the geometric central axis (12) in the flow direction (22) and is configured as a central shaft. A rotatably arranged scraper or wiper (36) is provided within the reactor housing (16); the scraper or wiper (36) has at least one scraper or wiper blade (42) to run along an interior side (44) of the reactor housing (16). The rotational movement of the scraper or wiper (36) results in radial mixing of a stream within the reactor housing (16) which dominates gravity effects and, by virtue of shaping of the scrapers or wipers, optionally makes plug flow or a loop flow or backflow within the reactor (10) or else via an additional external pumped circulation system (23) possible. This allows the reaction conditions in the axial direction of the reactor housing (16) to be predicted and individually suitable reaction conditions to be set and controlled along the reactor housing, so that, in particular, a desired molecular weight distribution can be set.
摘要:
The present invention relates to a reactor (10) and a process for continuous polymerization, where the reactor (10) has an essentially tubular reactor housing (16). The reactor housing (16) has a drive (38) which runs along the geometric central axis (12) in the flow direction (22) and is configured as a central shaft. A rotatably arranged scraper or wiper (36) is provided within the reactor housing (16); the scraper or wiper (36) has at least one scraper or wiper blade (42) to run along an interior side (44) of the reactor housing (16). The rotational movement of the scraper or wiper (36) results in radial mixing of a stream within the reactor housing (16) which dominates gravity effects and, by virtue of shaping of the scrapers or wipers, optionally makes plug flow or backflow within the reactor (10) possible. This allows the reaction conditions in the axial direction of the reactor housing (16) to be predicted and individually suitable reaction conditions to be set and controlled along the reactor housing, so that, in particular, a desired molecular weight distribution can be set.
摘要:
The present invention relates to a reactor (10) and a process for continuous polymerization, where the reactor (10) has an essentially tubular reactor housing (16). The reactor housing (16) has a drive (38) which runs along the geometric central axis (12) in the flow direction (22) and is configured as a central shaft. A rotatably arranged scraper or wiper (36) is provided within the reactor housing (16); the scraper or wiper (36) has at least one scraper or wiper blade (42) to run along an interior side (44) of the reactor housing (16). The rotational movement of the scraper or wiper (36) results in radial mixing of a stream within the reactor housing (16) which dominates gravity effects and, by virtue of shaping of the scrapers or wipers, optionally makes plug flow or a loop flow or backflow within the reactor (10) or else via an additional external pumped circulation system (23) possible. This allows the reaction conditions in the axial direction of the reactor housing (16) to be predicted and individually suitable reaction conditions to be set and controlled along the reactor housing, so that, in particular, a desired molecular weight distribution can be set.
摘要:
The present invention relates to water and solvent-free halogenated butyl rubber products as a process for the production thereof. The process comprises at least the steps of: a.) treating a fluid containing at least one halogenated butyl rubber and at least one volatile compound in at least one concentrator unit, b.) reheating the concentrated fluid and c.) feeding the reheated concentrated fluid into at least one extruder.
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:
A process for the isolation of polycarbonate produced by the interfacial polymerization process is disclosed. Accordingly, the process entails (a) evaporating the organic solvent from the solution that contains solvent and polycarbonate to obtain a material system that contains 90 to 99.95% polycarbonate, the percent being relative to the weight of the system, and (b) passing the material system through inlet openings of a separating vessel to obtain a plurality of streams of polycarbonate, on entry into the inlet openings said material system being supersaturated with volatile constituents to an extent of at least 1 bar and having a temperature of 250° to 340° C. and a flow rate of 0.1 to 20 kg/hour, and (c) degassing the streams in the separating vessel wherein the pressure is 0.1 to 20 mbar to effect degassing of the polycarbonate.