Sika Technology Ag

Andreas Kramer

Urs Burckhardt

Edis Kasemi

Ursula Stadelmann

Jürgen Finter

Jan Olaf Schulenburg

Ulrich Gerber

Karsten Frick

Juergen Finter

Michael Schlumpf

Urs Rheinegger

Jurgen Finter

Steffen Kelch

Norman Blank

Markus Haufe

Hans Häberle

Michael Gutgsell

Martin Schmider

Antonio Voci

Martin Konstanzer

A method for preparing an acid solution by contacting at least one aromatic carboxylic or sulfonic acid with at least one polyether having blocked hydroxyl groups as a solvent. The polyether having blocked hydroxyl groups is not volatile and exhibits a surprisingly high dissolving capacity for the aromatic carboxylic or sulfonic acid. The acid solution is very compatible in curable compositions and does not cause any emission or odor or migration effects. The acid solution is particularly suitable as a constituent of polyurethane compositions having latent curing agents for accelerating the hydrolysis of the latent reactive groups.

Solvent for aromatic carboxylic or sulfonic acids

A curing agent for epoxy resins, including at least one amine A1 of the formula (I) and at least one amine A2 which is a polyalkyleneamine or polyethyleneimine, where the weight ratio between amine A1 and amine A2 is in the range from 20/1 to 1/2. The curing agent of the invention enables inexpensive and low-emission epoxy resin products having good processability, long pot life, surprisingly rapid curing, especially also under cold conditions, high strength, high bond strengths, high glass transition temperature and a low tendency to yellowing, with formation of surprisingly nice surfaces having barely any blushing-related defects even in the case of two-dimensional application and under moist and cold conditions. Such epoxy resin products are advantageously usable as coating, especially for floors, or as adhesive.

Hardener for epoxy resins

A thixotropic agent for increasing the yield point of a curable composition, wherein the thixotropic agent includes (i) at least one urea compound from the reaction of at least one isocyanate with at least one amine and (ii) at least one polyether having blocked hydroxyl groups. The thixotropic agent is preparable in a simple manner and forms a spreadable paste which is firm at room temperature. It is particularly suitable as a constituent of moisture-curing polyurethane or SMP compositions, giving a good increase in the yield point thereof, without adversely affecting storage stability or migration characteristics. It enables phthalate-free adhesives, sealants or coatings that have surprisingly good conveyability coupled with a high yield point, and do not cause any problems with odor or fogging.

Thixotropic agent for curable compositions

Methods of using a curable composition, the curable composition including at least one polyether having blocked hydroxyl groups as the plasticizer on at least one alkaline substrate. The curable composition is storage-stable, easy to handle and highly elastic after curing, and does not show any tendency to separate or migrate. It enables elastic bonding, sealing or coating of alkaline substrates, such as, in particular, fresh or green concrete or cement mortar, without occurrence of troublesome odors triggered by plasticizer hydrolysis.

Curable composition for alkaline substrates

A composition containing calcium nitrate, at least one epoxy resin and at least one amine of formula (I). The composition allows the manufacture of low-emission epoxy-resin coatings that have good workability and that cure particularly rapidly in cold and damp conditions, without blushing-induced surface defects, thus achieving coatings of in particular high mechanical quality, with a minimal tendency to yellowing.

Accelerator for curing epoxy resins comprising alkylated amines

A moisture-curing polyurethane composition having a content of monomeric diisocyanates of at most 0.1 wt %, containing: at least one isocyanate-group-containing polyurethane polymer having a content of monomeric diisocyanates of at most 0.5 wt %, obtained from reaction of at least one monomeric diisocyanate with at least one polyether polyol at a NCO/OH ratio of at least 3/1 and subsequent removal of a large part of monomeric diisocyanates by way of a suitable separating method; and at least one polyether having blocked hydroxyl groups and free of isocyanate groups, as a plasticizer. Moisture-curing polyurethane composition is highly storage-stable when moisture is excluded, can be safely handled without special safety precautions, can be sold without hazard label, can be well processed, has long open time and has fast curing to form elastic material of high strength and extensibility, high cold flexibility, good adhesion properties and high stability with respect to heat and moisture.

Polyurethane composition having polymeric plasticizer and a low content of monomeric diisocyanates

A polyurethane composition, which contains at least one isocyanate-group-containing polymer, obtained from the reaction of at least one polyol with at least one diisocyanate, and at least one oxazolidine of the formula (I). The polyurethane composition allows one-component moisture-curing adhesives, sealants or coatings that have good storage stability, long open times and cure quickly to give a surprisingly non-tacky material having pronounced high-resilient properties.

Moisture-curing polyurethane composition containing oxazolidine

A curing agent for epoxy resins has N-benzylethane-1,2-diamine and N,N'-dibenzylethane-1,2-diamine in a weight ratio in the range from 65/35 to 95/5. The curing agent is easy to prepare, thins epoxy resins particularly well, and enables low-emission epoxy resin products that have good workability and a long pot-life, cure reliably and surprisingly fast and can be walked on after a short time, in particular even in cold conditions. Coatings of particularly high mechanical grade, with a high surface quality and a minimal tendency to yellowing, can thus be produced. Epoxy resins of this type are particularly suitable for coating floors.

A compound of formula (I) having advantageous properties when used as a latent curing agent for compositions containing isocyanate groups, and to compositions containing the compound of formula (I). The compound of formula (I) is odourless, is liquid and has comparatively low viscosity at room temperature and is stable in storage together with isocyanates. It makes possible odourless single-component polyurethane compositions which have good stability in storage, do not produce bubbles when cured in the presence of moisture, and cause no problematic odour emissions, giving a cured elastic material having good mechanical properties, good heat stability, a surprisingly non-adhesive surface and little tendency towards plasticizer migration.

Latent curing agent and curable polyurethane composition

The use of an aldehyde mixture containing 70 to 95 wt % of aldehydes of formula (I) and 5 to 30 wt % of alkylbenzene compounds not corresponding to formula (I) as a blocking agent for amines results in odorless, especially economically blocked amines, which at room temperature are typically liquid and have a surprisingly low viscosity. Such blocked amines are particularly suitable as latent hardeners in isocyanate-group-containing compositions. Single-component moisture-curing polyurethane compositions formulated therewith are surprisingly stable in storage, can be used for low-emission applications without odor problems and do not trigger any problems with plasticizer migration. Surprisingly, said compositions even have advantages over corresponding compositions having latent hardeners based on purified aldehydes of formula (I), in particular with respect to viscosity, storage stability and especially strength.

Blocking agent for amines, latent hardeners and polyurethane compositions

A curing agent for epoxy resin compositions containing at least one amine of formula (I) and at least one amine of formula (II). The curing agent is a low-odor, low-viscosity, low-toxicity curing agent and has a low propensity for carbamatization and a high reactivity toward epoxy resins. It enables low-odor and low-emission epoxy resin products which are readily processable and which even at low temperatures and high humidities undergo rapid and problem-free curing to afford high-quality plastics having a high hardness and a regular, non-tacky surface with high gloss.

Curing agent for low-emission epoxy resin compositions

Hydroxyaldimines of formula (I), their reaction products, in particular products of their reaction with polyisocyanates, and compositions including isocyanate groups and containing such reaction products. The hydroxyaldimine permits compositions which have good storage stability, a long open time, low odour, rapid, bubble-free curing and good mechanical properties, and which are not susceptible to plasticizer migration and have a particularly low content of monomeric diisocyanates. In particular, it permits reactive hot-melt adhesives with a particularly good workability.

Hydroxyaldimine and curable polyurethane composition with a low monomeric isocyanate content

A process for preparing a curing agent for epoxy resins, in which an amine mixture including at least one parent amine of the formula (I) and at least one alkylated amine of the formula (II) is reacted or adducted with at least one glycidyl ether of the formula (III). The amine mixture is especially a reaction mixture from the partial alkylation of the amine of the formula (I). The process described enables, with low energy expenditure and high space-time yield, curing agents of low odor, low toxicity, low viscosity and high reactivity for epoxy resins and epoxy resin products that cure rapidly at ambient temperatures and especially also under cold conditions and at the same time enable high-quality coatings having an even, shiny surface.

Method for producing a curing agent for low-emission epoxy resin compositions

A composition having at least one polyisocyanate and/or at least one isocyanate-group-containing polyurethane polymer and at least one latent hardener having aldimino group(s) of formula (I)&#x2014;as an elastic adhesive, sealant or coating, which is applied on at least one plasticiser migration sensitive substrate and/or is provided with at least one covering layer and a composite obtained therefrom. The method is characterized in that porous material or stress-crackforming plastics can be used without restriction as substrates and very different materials can be used without restriction as covering layers, without the occurrence of damage associated with plasticiser migration from the composition, such as bleeding, discoloring, spotting, softening, swelling or detachment.

Polyurethane composition with low plasticiser migration

Heat-curing epoxy resin compositions are characterized by high impact strength, good storage stability, and a low curing temperature. The epoxy resin compositions are suitable for use as a construction shell adhesive and for producing structural foams. They can already be cured in so-called bottom-baking conditions. Furthermore, it has been found that the use of an accelerator of the formula (Ia) or (Ib) results in an increase of the impact strength of heat-curing epoxy resin compositions.

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Zurich, Switzerland

Andreas Kramer