摘要:
The invention relates to an energy efficient, environmentally favourable process for preparing water and solvent-free rubber ionomers and/or polymer nanocomposites comprising said rubber ionomers.
摘要:
The invention relates to an energy efficient, environmentally favourable process for preparing water and solvent-free rubber ionomers and/or polymer nanocomposites comprising said rubber ionomers.
摘要:
An integrated process for the solution polymerization and subsequent halogenation of butyl rubber in a common medium is disclosed. The process comprises providing a solution polymerization reactor containing a C6 medium mixed with a monomer mixture comprising at least an isoolefin monomer and a multiolefin monomer in a mass ratio of monomer mixture to medium of from 61:39 to 80:20. Once polymerized, residual unreacted monomer mixture is separated from the rubber solution using a distillation process. The residual monomers may then be purified and recycled back into the reactor. The separated rubber solution is then halogenated. The process obviates the need for separating the rubber from the medium following polymerization, then re-dissolving it in another solvent for halogenation, thereby saving energy cost. The process optionally employs heat exchangers for the reactor feed streams to further reduce energy consumption.
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:
An integrated process for the solution polymerization and subsequent halogenation of butyl rubber in a common medium is disclosed. The process comprises providing a solution polymerization reactor containing a C6 medium mixed with a monomer mixture comprising at least an isoolefin monomer and a multiolefin monomer in a mass ratio of monomer mixture to medium of from 61:39 to 80:20. Once polymerized, residual unreacted monomer mixture is separated from the rubber solution using a distillation process. The residual monomers may then be purified and recycled back into the reactor. The separated rubber solution is then halogenated. The process obviates the need for separating the rubber from the medium following polymerization, then re-dissolving it in another solvent for halogenation, thereby saving energy cost. The process optionally employs heat exchangers for the reactor feed streams to further reduce energy consumption.
摘要:
The present invention provides a process for preparing cyclic 1,3-keto esters in the absence of solvent, using solid-state or high viscosity reactors.
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 standardized 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:
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.
摘要:
The invention describes a process for the preparation of polycarbonate. The process includes (a) transesterifying at least one aromatic dihydroxyaryl compound and a diaryl carbonate in the melt in the presence of a catalyst, (b) mixing the melt obtained in step (a) with a foaming agent (c) passing the mixture at 250 to 340° C. through inlet openings of a separating vessel at a rate of 0.1 to 20 kg/hour, to obtain a plurality of streams of foamed polycarbonate and degassing the streams of foamed polycarbonate in the separating vessel wherein the pressure is 0.1 to 20 mbar.