The present invention relates to isocyanate-terminated prepolymers based on polyoxymethylene-polyoxyalkylene block copolymers, to a process for their preparation, and to the use of these isocyanate-terminated prepolymers as isocyanate components in 1- and 2-component systems for coatings, adhesives and sealants.

A process for producing a polyoxymethylene-polyoxyalkylene copolymer is provided. The process comprises reacting a polymer formaldehyde compound of an alkylene oxide and a specific component (X) in the presence of a double metal cyanide (DMC) catalyst. A polyoxymethylene-polyoxyalkylene copolymer can be obtained by means of such a process and to the use of same for producing a polyurethane polymer.

The disclosure relates to moisture curable compositions based on a combination of silane-modified polymer and silane functional additive, their manufacture and use. The silane functional additive is preferably prepared from a water miscible polyol having a functionality of about 2 to about 4 and/or a polyol having a tertiary nitrogen atom in the backbone and a functionality equal or greater than about 2.

To provide a polyether polyol having a high degree of freedom in the design of a polyurethane foam, and capable of providing a polyol system solution excellent in storage stability. A polyether polyol having a polyoxyalkylene chain consisting of oxyalkylene units, and having a degree of unsaturation of at most 0.020 meq/g, a hydroxy value of from 1 to 80 mgKOH/g, a content of oxyethylene units of from 0 to 50 mass %, and a content of ultra-high molecular weight components which have molecular weights of from 12 to 46 times the number average molecular weight of at most 1,000 mass ppm. The number average molecular weight is a molecular weight as calculated as polystyrene measured by gel permeation chromatography (GPC) method, and the content of ultra-high molecular weight components is a value measured by high performance liquid chromatography (HPLC) method using a charged aerosol detector (CAD).

A moisture-curable composition, including: a) at least one polyurethane polymer P having isocyanate groups; b) at least one blocked polyamine BA having blocked, hydrolytically activatable amino groups; and c) at least one monoamine MA of formula (V),

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where R.sup.a represents a linear, cyclic, or branched alkyl or alkenyl radical or optionally substituted aryl radical with 1 to 12 C atoms and optionally including ether oxygen atoms; R.sup.b and R.sup.c either independently represent a rest R.sup.a or a hydrogen atom, where at least one of R.sup.b and R.sup.c is a hydrogen atom, or R.sup.b and R.sup.c together with the N atom of monoamine MA form an aldimine group that under influence of water hydrolyzes to a aldehyde and an amine R.sup.a—NH.sub.2; wherein polymer P is the reaction product of 2,4- and/or 2,6-toluylene diisocyanate (TDI) and at least one polyol, wherein the polyol has an average functionality of >2.

A moisture-curable composition, including at least one organic polymer P containing reactive silane groups, between 1.0 wt.-% and 25.0 wt.-%, preferably between 2.0 wt.-% and 20 wt.-%, in particular between 2.5 wt.-% and 10 wt.-%, based on the total composition, of dimethyl or diethyl esters of aliphatic C3 to C5 dicarboxylic acids, and at least one curing catalyst for alkoxysilane groups. The moisture-curable composition is particularly suitable as elastic adhesive, coating, filler, or sealant and shows superior overpaintability, in particular with automotive topcoats or similar paints.

This invention relates to an in-situ formed polyol blend having an overall functionality of 2 to 3 and an overall hydroxyl number of 50 to 150. A process for preparing these polyol blends is also disclosed. These in-situ formed polyol blends are suitable for preparing viscoelastic flexible polyurethane foams. A process for preparing these foams is also disclosed.

The present invention relates to a method for preparing polyether carbonate polyols by adding alkylene oxide and carbon dioxide to a H-functional starter substance in the presence of a DMC catalyst or a metal complex catalyst based on the metals cobalt and/or zinc, wherein (γ) alkylene oxide and carbon dioxide are added to a H-functional starter substance in a reactor in the presence of a DMC catalyst or a metal complex catalyst based on the metals cobalt and/or zinc, characterized in that the alkylene oxide contains a proportion of 5 to 50 wt. % ethylene oxide, based on the overall weight of the alkylene oxide used, and the addition of the ethylene oxide is carried out in an atmosphere containing carbon dioxide.

In an active energy ray-curable polyurethane resin including a reaction product of a resin material containing an isocyanate group-terminated prepolymer and a hydroxy group-containing unsaturated compound, the isocyanate group-terminated prepolymer includes a reaction product of a prepolymer material containing a polyisocyanate component containing a xylylene diisocyanate and/or a hydrogenated xylylene diisocyanate, and a polyol component containing a polyoxyalkylene polyol having a number average molecular weight of 6000 or more and 12000 or less, and the viscosity at 25° C. of the active energy ray-curable polyurethane resin is 20000 mPa.Math.s or more and 40000 mPa.Math.s or less.

An on-orbit recycling method for a buffer foam of a cargo spacecraft includes the following steps: mechanically cutting a shaped PU foam into foam micro-blocks, and putting the foam micro-blocks into a packaging bag for packaging, where the packaging bag is filled with a foaming adhesive; the foaming adhesive includes a component A and a component B, which are independently packaged in a two-component packaging bag; and the component A and the component B are separated by a film; and squeezing the film between the component A and the component B, such that the two components are fully mixed, foamed and expanded to finally burst the two-component packaging bag, where after the packaging bag is burst, the foaming adhesive expands into gaps of the foam micro-blocks; and in a microgravity state of space, the foaming adhesive expands and fills uniformly in all directions and fully infiltrates the foam micro-blocks.