Abstract:
A process for preparing a mixture of polyhydroxyl compounds having low molecular weight by catalytically hydrogenating a formose mixture with hydrogen on a metal catalyst. The hydrogenation is carried out at a pH of 7.5 to 12.5 and at elevated temperature and pressure. The formose mixture comprises (i) up to 70 wt. % formose, (ii) up to 1.6 wt. % lead ions and (iii) up to 5 wt. % calcium ions with at least one of (ii) or (iii) being present. The catalyst which is present in an amount of 4-240 wt. % (based on formose solution) is a compound taken from the group consisting of nickel, cobalt and compounds thereof. The mixture of polyhydroxyl compounds made in accordance with the present invention is useful as a starting material in the production of polyether polyols, polyester polyols and polyurethane plastics.
Abstract:
The present invention relates to polyisocyanate compositions containing reversibly blocked catalysts for the isocyanate addition reaction, characterized in that they contain (a) at least one organic polyisocyanate, (b) at least one addition product dissolved or dispersed in the polyisocyanate compositions, of a sulfonyl isocyanate with a tertiary amine and/or with a catalyst having a tin(II)- or tin(IV)-carboxylate structure as the reversibly blocked catalyst. The present invention also relates to a process for producing these polyisocyanate compositions and to the use of new polyisocyanate compositions as reactants for compounds containing isocyanate-reactive groups for the production of isocyanate addition products such as polyurethane plastics using a one-component or two-component principle. The present invention finally relates to the latent polyurethane catalysts prepared from a sulfonyl isocyanate and a tin(II)- or tin(IV)-carboxylate.
Abstract:
PURPOSE: To obtain the subject structural material exhibiting longitudinal and lateral elasticity, comprising an organic textile having a specific elasticity and having a longitudinal extensibility of at least a constant value before hardening of the resin applied to the textile. CONSTITUTION: This organic textile having 200-2,500 daN/mm elasticity (e.g. a sheet-like structural material of polyester and/or polyamide and/or cotton fibers) and having extensibility in the longitudinal direction of at least 10% before hardening of a synthetic resin applied to the textile is dipped and/or covered with a water-hardenable reactive synthetic resin (e.g. polyurethane) to obtain a textile sheet-like structural material useful in preparing orthopedic support dressings or industrial devices having longitudinal and lateral elasticity. A raschel fabric is suitable as the textile sheet.