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.

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.

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.

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.

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.

Resin particles each include a binder resin. The binder resin includes an amorphous polyester resin and a crystalline resin. The amorphous polyester resin includes alcohol monomers as one of constituent components. The alcohol monomers include propylene glycol. Abundance of the crystalline resin in a region from an outermost surface of each of the resin particles to a depth of 150 nm from the outermost surface is 4% or less relative to an amount of the crystalline resin in an entire region of each of the resin particles. A radiocarbon .sup.14C content of the resin particles is 5.4 pMC or greater.

Resin particles each include a binder resin. The binder resin includes an amorphous polyester resin and a crystalline resin. The amorphous polyester resin includes alcohol monomers as one of constituent components. The alcohol monomers include propylene glycol. Abundance of the crystalline resin in a region from an outermost surface of each of the resin particles to a depth of 150 nm from the outermost surface is 4% or less relative to an amount of the crystalline resin in an entire region of each of the resin particles. A radiocarbon .sup.14C content of the resin particles is 5.4 pMC or greater.

A process for preparing an aldol ester of the formula (I), wherein at least one carboxylic anhydride of the formula (II) is reacted with at least one aldol of the formula (III) with heating in the presence of a basic catalyst with a pKa of the conjugate acid of at least 8, and the reaction product obtained from the process. The process provides a light-coloured and low-odour reaction product which has a high content of aldol ester content of the formula (I) and can be used, without elaborate purification steps, particularly without overhead distillation of the aldol ester, as a blocking agent for primary amines. The resultant blocked amines have a long storage life together with polymers containing isocyanate groups, and cure rapidly and reliably on contact with moisture to form mechanically high-grade and robust elastomers.

A process for preparing an aldol ester of the formula (I), wherein at least one carboxylic anhydride of the formula (II) is reacted with at least one aldol of the formula (III) with heating in the presence of a basic catalyst with a pKa of the conjugate acid of at least 8, and the reaction product obtained from the process. The process provides a light-coloured and low-odour reaction product which has a high content of aldol ester content of the formula (I) and can be used, without elaborate purification steps, particularly without overhead distillation of the aldol ester, as a blocking agent for primary amines. The resultant blocked amines have a long storage life together with polymers containing isocyanate groups, and cure rapidly and reliably on contact with moisture to form mechanically high-grade and robust elastomers.

A polyurea composition including a first component A with at least one isocyanate-functional polyurethane polymer P1 and a second component B including a blocked amine BA and optionally a polyamine PA having a molecular weight in the range from 60 to 500 g/mol. The polyurea composition further includes a silane S1 selected from the list consisting of isocyanatosilanes S1-1 and epoxy silanes S1-2 as well as an aminosilane S2 and an aggregate AG of an at 23° C. solid thermoset. The polyurea composition is notable for high surface roughness and for reliable and long-term bonding of the aggregates to the coating with no need for sealing. Further, the polyurea composition has enough adhesion to the substrate that the application of a primer layer on the substrate prior to application is not necessary.