Abstract: A method for reliably avoiding backflow in the transport of a liquid under pressure via a transport pipe (1), in which a shut-off device (2) with differential pressure switching is arranged, into a container (3) which is under pressure and which comprises the liquid to be transported and/or another liquid is proposed, wherein a pressure accumulator (4) which is filled with the liquid to be transported up to a certain level and above the liquid level, in direct contact with the liquid to be transported, with an inert gas is arranged in the transport pipe (1) upstream from the shut-off device (2) in the transport direction, the inert gas being provided in the pressure accumulator (4) under an excess pressure and in an amount relative to the container (3) to be filled which are designed so that, in the case of a drop in the pressure in the transport pipe (1), the inert gas ensures a positive pressure difference in the transport pipe (1) to the container (3) over a period which is at least as long as the reaction

Abstract: The present invention relates to a process for reacting glycolaldehyde with an aminating agent in the presence of hydrogen and of a catalyst, the catalyst being activated by reducing a catalyst precursor or by reducing a passivated catalyst, which comprises effecting the reaction in the presence of a solvent and contacting the glycolaldehyde with the activated catalyst.

Abstract: The present invention relates to a process for preparing ethanolamines by reacting glycolaldehyde with monoethanolamine and/or diethanolamine in the presence of a catalyst.

Abstract: The present invention relates to a process for preparing 3-dimethylaminopropylamine (DMAPA) by reacting 3-dimethylaminopropionitrile (DMAPN) with hydrogen in the presence of a catalyst, wherein the DMAPN used has a content of 2-(dimethylaminomethyl)glutaronitrile (DGN) of 300 ppm by weight or less, based on the DMAPN used. Furthermore, the present invention relates to mixtures of DMAPN and DGN, wherein the weight ratio of DMAPN to DGN is in the range from 1 000 000:5 to 1 000 000:250.

Abstract: The present invention relates to a process for reacting glycolaldehyde with an aminating agent in the presence of hydrogen and of a catalyst, the catalyst being activated by reducing a catalyst precursor or by reducing a passivated catalyst, which comprises effecting the reaction in the presence of a solvent and contacting the glycolaldehyde with the activated catalyst.

Abstract: The present invention relates to a process for preparing ethanolamines by reacting glycolaldehyde with monoethanolamine and/or diethanolamine in the presence of a catalyst.

Abstract: The present invention relates to a process for preparing 3-dimethylaminopropylamine (DMAPA) by reacting 3-dimethylaminopropionitrile (DMAPN) with hydrogen in the presence of a catalyst, wherein the DMAPN used has a content of 2-(dimethylaminomethyl)glutaronitrile (DGN) of 300 ppm by weight or less, based on the DMAPN used. Furthermore, the present invention relates to mixtures of DMAPN and DGN, wherein the weight ratio of DMAPN to DGN is in the range from 1 000 000:5 to 1 000 000:250.

Abstract: A method for reliably avoiding backflow in the transport of a liquid under pressure via a transport pipe (1), in which a shut-off device (2) with differential pressure switching is arranged, into a container (3) which is under pressure and which comprises the liquid to be transported and/or another liquid is proposed, wherein a pressure accumulator (4) which is filled with the liquid to be transported up to a certain level and above the liquid level, in direct contact with the liquid to be transported, with an inert gas is arranged in the transport pipe (1) upstream from the shut-off device (2) in the transport direction, the inert gas being provided in the pressure accumulator (4) under an excess pressure and in an amount relative to the container (3) to be filled which are designed so that, in the case of a drop in the pressure in the transport pipe (1), the inert gas ensures a positive pressure difference in the transport pipe (1) to the container (3) over a period which is at least as long as the reaction

Abstract: The invention relates to a process for preparing polyesterols from at least one base polyesterol and at least one further reagent, wherein (a) the at least one base polyesterol and the at least one further reagent are mixed, (b) the mixture produced in (a) flows through a reactor in which at least one packing comprising at least one immobilized enzyme on a support is present, with the at least one base polyesterol and the at least one further reagent being reacted to form the polyesterol.

Abstract: Polyesterols having reduced reactivity are prepared by catalytic polycondensation of dicarboxylic acids/dicarboxylic acid derivatives and H-functional substances using tin catalysts by a process wherein the polyesterols are brought into contact with oxygen after the end of the esterification reaction. The polyesterols themselves obtained by this process are used for the preparation of PU.

Abstract: The present invention relates to a two-stage process for preparing polyesterols, which comprises the following process steps: a) preparation of at least one base polyesterol by reaction of in each case at least one dicarboxylic acid with in each case at least one polyhydroxyl compound, b) reaction of the base polyesterol from a) or a mixture of the base polyesterols from a) with at least one enzyme and, if appropriate, additionally with polyhydroxyl compounds. The invention further relates to a polyesterol obtainable by the above process.

Abstract: Plastics comprise sterically hindered, esterified amine (I) which contains less than 100 ppm, based on the weight of (I), of titanium.

Abstract: Polyesterols having reduced reactivity are prepared by catalytic polycondensation of dicarboxylic acids/dicarboxylic acid derivatives and H-functional substances using tin catalysts by a process wherein the polyesterols are brought into contact with oxygen after the end of the esterification reaction. The polyesterols themselves obtained by this process are used for the preparation of PU.

Abstract: Plastics comprise sterically hindered, esterified amine (I) which contains less than 100 ppm, based on the weight of (I), of titanium.