摘要:
The invention relates to a process for the production of liquid, storage-stable isocyanate mixtures with a low color index having carbodiimide-(CD) and/or uretone imine (UI) groups, the isocyanate mixtures that can be obtained by this process and their use for the production of blends with other isocyanates or for the production of isocyanate group-containing pre-polymers and also of polyurethane plastics, preferably polyurethane foamed plastics.
摘要:
The invention relates to a process for the production of liquid, storage-stable isocyanate mixtures with a low color index having carbodiimide-(CD) and/or uretone imine (UI) groups, the isocyanate mixtures that can be obtained by this process and their use for the production of blends with other isocyanates or for the production of isocyanate group-containing pre-polymers and also of polyurethane plastics, preferably polyurethane foamed plastics.
摘要:
The invention provides a process for the preparation of polyamines of the diphenylmethane series. This process comprises a) reacting aniline and formaldehyde in a molar ratio of 1.5:1 to 6:1, in the presence of an acid catalyst at temperatures of 20° C. to 100° C., in which the water content in the acid reaction mixture is
摘要:
The invention relates to a method of producing polyisocyanates of the diphenylmethane series including the steps of a) reacting aniline and formaldehyde in the presence of HCl to provide a product mixture containing polyamines of the diphenylmethane series, HCl, aniline and water; b) removing excess aniline and water by distillation to provide a product mixture comprising polyamines of the diphenylmethane series, HCl, no more than 10 wt. % aniline based on the polyamines, and no more than 5 wt. % water based on the polyamines; and c) phosgenating the product mixture in (b).
摘要:
The invention provides a process for the preparation of polyamines of the diphenylmethane series. This process comprises a) reacting aniline and formaldehyde in a molar ratio of 1.5:1 to 6:1, in the presence of an acid catalyst at temperatures of 20° C. to 100° C., in which the water content in the acid reaction mixture is
摘要:
The invention relates to a process for the preparation of liquid, storage-stable isocyanate mixtures which are characterized by a low color number and which contain carbodiimide (CD) and/or uretonimine (UI) groups. This invention also relates to the isocyanate mixtures obtained by this process, to their use for the preparation of blends with further isocyanates, and to the preparation of prepolymers containing isocyanate groups and of polyurethane plastics, preferably polyurethane foams from these isocyanate mixtures.
摘要:
The invention relates to a process for the preparation of liquid, storage-stable isocyanate mixtures which are characterized by a low color number and which contain carbodiimide (CD) and/or uretonimine (UI) groups. This invention also relates to the isocyanate mixtures obtained by this process, to their use for the preparation of blends with further isocyanates, and to the preparation of prepolymers containing isocyanate groups and of polyurethane plastics, preferably polyurethane foams from these isocyanate mixtures.
摘要:
The invention relates to an improved process for the production of isocyanates by the reaction of an amine or a mixture of two or more amines with phosgene, the improvement involving the phosgene containing less than about 100 ppm of sulfur in elemental or bound form. The inventive process yields light-colored isocyanates that are suitable for the production of polyurethanes or their precursors (e.g. prepolymers) without the treatment processes heretofore required.
摘要:
Di- and polyamines of the diphenylmethane series are prepared by a) mixing a first portion of aniline with an acid catalyst, b) mixing a second portion of aniline with formaldehyde, and c) mixing and reacting the mixtures prepared in each of steps a) and b). The diamines produced by this process may then be phosgenated to produce the corresponding di-/polyisocyanate.
摘要:
Di- and polyamines of the diphenylmethane series are prepared by a) mixing a first portion of aniline with an acid catalyst, b) mixing a second portion of aniline with formaldehyde, and c) mixing and reacting the mixtures prepared in each of steps a) and b). The diamines produced by this process may then be phosgenated to produce the corresponding di-/polyisocyanate.