摘要:
A process for the continuous production of an aqueous polyurethane dispersion based on at least one aliphatic and/or aromatic polyisocyanate is described, which is characterised by the following steps: a) production of an aqueous pre-emulsion by mixing a polyurethane prepolymer containing hydrophilic and/or potentially hydrophilic groups with water in a mixing nozzle, wherein the polyurethane prepolymer is injected into the water; b) formation of an emulsion by homogenization of the pre-emulsion from step a) in a multi-step homogenizing nozzle. Paint films containing the aqueous polyurethane dispersion produced by the process can be used to coat substrates.
摘要:
A process for the continuous production of an aqueous polyurethane dispersion based on at least one aliphatic and/or aromatic polyisocyanate is described, which is characterised by the following steps: a) production of an aqueous pre-emulsion by mixing a polyurethane prepolymer containing hydrophilic and/or potentially hydrophilic groups with water in a mixing nozzle, wherein the polyurethane prepolymer is injected into the water; b) formation of an emulsion by homogenisation of the pre-emulsion from step a) in a multi-step homogenising nozzle. Paint films containing the aqueous polyurethane dispersion produced by the process can be used to coat substrates.
摘要:
The invention describes a homogenising nozzle 100 comprising a casing 10, a piston 11 arranged displaceably along the longitudinal axis of the casing 10, a first inlet 14 for a first component, a second inlet 15 for a second component and an outlet 16 for a homogenised mixture of the first and second components, wherein the first inlet 14 and the outlet 16 are arranged along the longitudinal axis of the casing 10 in such a manner that, by displacing the piston 11, the free cross-section of the first inlet 14 and the free cross-section of the outlet 16 may be varied. A process is furthermore described for the production of an aqueous two-component polyurethane coating emulsion by mixing at least one aqueous binder dispersion comprising isocyanate-reactive groups and a polyisocyanate using the described homogenising nozzle.
摘要:
The present invention relates to a process for the production of a polyether polyol by polyaddition of an alkylene oxide onto a starter compound containing active hydrogen atoms conducted in the presence of a double metal cyanide catalyst comprising conducting a reaction mixture at least once through a zone which has an energy density of at least 5×106 J/m3, wherein the dwell time of the reaction mixture in this zone is at least 10−6 seconds per pass.
摘要翻译:本发明涉及一种生产聚醚多元醇的方法,该方法是通过在双金属氰化物催化剂的存在下将烯化氧加成到含有活性氢原子的起始化合物上,包括将反应混合物至少一次通过一个 具有至少5×10 6 J / m 3的能量密度,其中该区域中反应混合物的停留时间为每次通过至少10 -6秒。
摘要:
The present invention relates to a process for the production of polyether polyols by polyaddition of alkylene oxides onto starter compounds containing active hydrogen atoms conducted in the presence of a double-metal cyanide catalyst wherein a reaction mixture is guided at least once through a zone which has an energy density of at least 105 J/m3 and wherein the residence time of the reaction mixture in this zone is at least 10−6 seconds per pass.
摘要翻译:本发明涉及一种生产聚醚多元醇的方法,该方法是在双金属氰化物催化剂的存在下,将环氧烷烃加成到含有活性氢原子的起始物上,其中反应混合物至少引导一次通过具有 至少10 5 J / m 3的能量密度,其中反应混合物在该区域中的停留时间为每次通过至少10 -6秒。
摘要:
A process for the preparation of polymeric condensates, wherein the reaction mixture is fed at least once during the condensation reaction through a zone of high energy density which has an energy density of at least 105 J/m3.
摘要:
Continuous processes for preparing polycarbonates having a weight average molecular weight Mw, of 15,000 to 200,000 g/mol, the processes comprising reacting a dihydroxydiarylalkane and phosgene in the presence of a catalyst in a phase boundary process comprising: continuously dispersing in a disperser an organic phase comprising at least a portion of the phosgene and a solvent suitable for the polycarbonate and an aqueous phase comprising the dihydroxydiarylalkane, water and an alkali solution present in an amount of 1.5 to 2.5 moles per mole of the dihydroxydiarylalkane, to form a mixture; reacting the mixture in a first reactor with a residence time of less than 0.5 seconds; further reacting the mixture in a second reactor with addition of further alkali solution and, optionally, a chain terminator; and effecting further condensation in a third reactor with addition of further alkali solution and, optionally, a chain terminator, in the presence of the catalyst.
摘要:
The invention relates to a device (1) for the treatment of substance mixtures conveyed under high pressure, with a casing (3) surrounding a high-pressure space (2), with at least one sealing means (12) in order to seal off the high-pressure space (2) with respect to the surroundings, and with an inlet (4) and an outlet (5) in order respectively to supply the substance mixture to be treated to the high-pressure space (2) and to discharge it from the high-pressure space (2). The high-pressure space (2) is closed, via at least one cover for mounting and demounting, by a processing module arranged in the high-pressure space (2), the cover having a central fastening means (6) which can be locked, oriented coaxially with respect to the casing (3).
摘要:
Continuous processes for preparing polycarbonates having a weight average molecular weight MW, of 15,000 to 200,000 g/mol, the processes comprising reacting a dihydroxydiarylalkane and phosgene in the presence of a catalyst in a phase boundary process comprising: continuously dispersing in a disperser an organic phase comprising at least a portion of the phosgene and a solvent suitable for the polycarbonate and an aqueous phase comprising the dihydroxydiarylalkane, water and an alkali solution present in an amount of 1.5 to 2.5 moles per mole of the dihydroxydiarylalkane, to form a mixture; reacting the mixture in a first reactor with a residence time of less than 0.5 seconds; further reacting the mixture in a second reactor with addition of further alkali solution and, optionally, a chain terminator; and effecting further condensation in a third reactor with addition of further alkali solution and, optionally, a chain terminator, in the presence of the catalyst.