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.

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.

A method for producing a binder resin by a reaction of a cellulose derivative, a polyvinyl acetal, and a bonding agent that has in the molecule at least two functional groups that can react to hydroxyl groups in the polyvinyl acetal and the cellulose derivative. In the production method, the content of the bonding agent is at least double the molar quantity of whichever has the greater number of moles between the polyvinyl acetal and the cellulose derivative. The produced binder resin is favorable in a coating paste such as a conductive paste, and causes an improvement in film quality such as the smoothness and denseness of a coating film formed by the paste.

A method for producing a binder resin by a reaction of a cellulose derivative, a polyvinyl acetal, and a bonding agent that has in the molecule at least two functional groups that can react to hydroxyl groups in the polyvinyl acetal and the cellulose derivative. In the production method, the content of the bonding agent is at least double the molar quantity of whichever has the greater number of moles between the polyvinyl acetal and the cellulose derivative. The produced binder resin is favorable in a coating paste such as a conductive paste, and causes an improvement in film quality such as the smoothness and denseness of a coating film formed by the paste.

The invention relates to a method for producing a polyoxymethylene polyoxyalkylene block copolymer, said method including the process of reacting a polymer formaldehyde compound with alkylene oxide in the presence of a double metal cyanide (DMC) catalyst and an H-functional starter substance, wherein the theoretical molar mass of the polymer formaldehyde compound is lower than the theoretical molar mass of the H-functional starter substance, and the polymer formaldehyde compound has at least one terminal hydroxyl group, the theoretical molar mass of the H-functional starter substance being at least 500 g/mol. In the method according to the invention, a mixture i) is provided comprising the DMC catalyst and the H-functional starter substance in step (i); the polymer formaldehyde compound is then added to the mixture (i) in step (ii), thereby forming a mixture (ii); and the alkylene oxide is added in step (iii), step (ii) being carried out at the same time as or prior to step (iii).

The invention relates to a process for preparing prepolymers that comprise a polyoxymethylene block. The invention also relates to prepolymers that can be obtained by said process and to mixtures of the prepolymers with OH-reactive compounds, preferably polyisocyanates. The invention further relates to a chemical-technical process for preparing a chemical product of defined composition.

In a process for producing polyoxymethylene-polyalkylene oxide block copolymers comprising the step of polymerizing an alkylene oxide in the presence of an OH-terminated polyoxymethylene polymer and a catalyst, the polyoxymethylene polymer has a number-average molecular weight Mn determined after derivatization with propylene oxide and gel permeation chromatography against polystyrene standards with tetrahydrofuran as the eluent of ≥1100 g/mol to ≤2300 g/mol and the ratio of alkylene oxide to polyoxymethylene polymer is ≥0.05 mol/g. The invention further relates to copolymers obtainable by the process, to a process for producing polyurethane polymers using these copolymers and to polyurethanes obtainable therefrom.

In a process for producing polyoxymethylene-polyalkylene oxide block copolymers comprising the step of polymerizing an alkylene oxide in the presence of an OH-terminated polyoxymethylene polymer and a catalyst, the polyoxymethylene polymer has a number-average molecular weight Mn determined after derivatization with propylene oxide and gel permeation chromatography against polystyrene standards with tetrahydrofuran as the eluent of ≥1100 g/mol to ≤2300 g/mol and the ratio of alkylene oxide to polyoxymethylene polymer is ≥0.05 mol/g. The invention further relates to copolymers obtainable by the process, to a process for producing polyurethane polymers using these copolymers and to polyurethanes obtainable therefrom.

A method for producing a prepolymer for the production of an integral polyurethane foam is provided. The prepolymer is or can be obtained by reaction of a composition that contains the following components: component A containing a polyoxymethylene-polyoxyalkylene block copolymer having a hydroxyl number of 20 mg KOH/g to 200 mg KOH/g as component Al, component B containing di- and/or polyisocyanates with an NCO content of 15 to 45 wt.-% relative to component B, 0.04 to 1.0 wt.-%, relative to the composition, a proton acid as component C, and optionally a component D that contains auxiliary agents, at a characteristic number of 450 to 850. The invention further relates to the prepolymer obtained by the method, to an integral polyurethane foam based on the prepolymer, and to the use thereof.