Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and a process for the preparation of a hardening accelerator composition by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction of the water-soluble calcium compound with the water-soluble silicate compound being carried out in the presence of an aqueous solution which contains a water-soluble comb polymer suitable as a plasticizer for hydraulic binders. The invention concerns also a composition of calcium silicate hydrate and comb polymer, its use as hardening accelerator and for the reduction of the permeability of hardened compositions.

Abstract: A process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound, said reaction being effected in the presence of a water-soluble dispersant having at least one polyalkyleneglycol structural unit with a functional group at one end of the polyalkyleneglycol, being able to interact as an anchor group with the surface of cement particles, the hardening accelerator composition and its use.

Abstract: The water retention agents according to the invention are outstandingly suitable as additives in construction chemistry systems and in the development, exploitation and completion of underground mineral oil and natural gas deposits and in deep wells, their effect being particularly advantageous at increased temperatures and because of their lack of influence on the rheological properties of the well slurries.

Abstract: The invention describes amphiphilic polymer compounds which are prepared by a) reacting a di-, tri- or tetraglycidyl compound (A) with an optionally unsaturated reactive component (B) consisting of C8-C28-fatty acid, a C8-C28-alcohol or a secondary C8-C28-amine, and allowing b1) the reaction product from stage a) to react further first with b1?) an aliphatic or aromatic polyisocyanate compound (C) b1?) and optionally then with a polyalkylene oxide compound (D), and b1?) reacting the reaction product from stage b1?) or optionally b1?) with a component (E) which is reactive towards isocyanates and has at least one OH, NH2, NH or SH group, or b2) allowing the reaction product from stage a) to react to completion with the reaction product of component (C) with component (E) and optionally (D) and (C), or b3) allowing the reaction product from stage a) to react to completion with the reaction product from component (C) and component (D) and optionally (C) and optionally the reaction product of component (C) and

Abstract: Disclosed is a polycondensation product that is a reaction product of A) an aromatic or heteroaromatic compound containing 5 to 10 C atoms or heteroatoms and is provided with an average of 1 to 300 oxyethylene groups and/or oxypropylene groups per molecule which are linked to the aromatic or heteroaromatic compound via an O atom or N atoms, and B) an aromatic compound and C) an aldehyde selected among the group of formaldehyde, glyoxylic acid, and benzaldehyde or mixtures thereof. Surprisingly, the inventive polycondensation product causes very good liquefaction of hydraulic binding agents, eg. Cement, resulting in substantially improved liquefaction of the construction material at a lower dose while pourability can be maintained over a longer period of time as opposed to naphthalene sulfonates or melamine sulfonates.

Abstract: The invention relates to copolymers based on phosphorous-containing monomers (A) and on macromonomers (B), to methods for the production thereof and to their use as additives for inorganic binding agent suspensions based on cement, lime, gypsum and anhydrite. The corresponding polymeric additives have, as flow agents, excellent water-reducing properties and hold the flowability of the concrete over a relatively long period of time (60 to 90 min.) to an almost unchanged level without having delayed action. In addition, the corresponding polymeric additives improve the processing and setting processes of the building materials produced with these additives by making possible earlier and higher resistances to pressure.

Abstract: The invention relates to a copolymer which is suitable as a superplasticizer for hydraulic binders and comprises 5 to 55 mol % of an isoprenol polyether derivative structural unit, 2 to 90 mol % of an acrylic acid derivative structural unit and 2 to 90 mol % of a hydroxyalkyl acrylate structural unit.

Abstract: The invention relates to a process for the preparation of polymers by free radical polymerization of monomers in the presence of water, electrochemically produced free radicals being used for initiating the free radical polymerization.

Abstract: The invention relates to a process for the preparation of an aqueous solution comprising 30 to 95% by weight of water and 5 to 70% by weight of a copolymer dissolved in the water by free radical solution polymerizations of an isoprenol polyether derivative with an acrylic acid derivative, so that the copolymer has 20 to 45 mol % of an isoprenol polyether derivative structural unit and 55 to 80 mol % of an acrylic acid derivative structural unit. The aqueous solution is suitable as a superplasticizer for hydraulic binders.

Abstract: The invention relates to a copolymer which can be used as a superplasticizer for hydraulic binders and comprises 30 to 47 mol % of a (meth)allyl alcohol polyether derivative structural unit and 53 to 70 mol % of a maleic acid derivative structural unit.

Abstract: The invention relates to a process for the preparation of a copolymer in a semicontinuous mode of operation in a polymerization apparatus containing a polymerization reactor connected to a metering device, in each case acid monomer being initially introduced into the metering device and polyether macromonomer and water into the polymerization reactor, acid monomer being metered from the metering device into the polymerization reactor, free radical polymerization initiator being passed into the polymerization reactor before and/or during the metering of the acid monomer into the polymerization reactor, so that an aqueous medium forms in the polymerization reactor, in which aqueous medium acid monomer and polyether macromonomer are reacted by free radical polymerization with formation of the copolymer, at least 70 mol % of the polyether macromonomer initially introduced into the polymerization reactor being converted by the free radical polymerization, the conversion of the acid monomer giving rise in the copol

Abstract: Water-soluble copolymers and terpolymers as stabilizers for aqueous building material systems and water-based paint and coating systems are described. Advantages of the copolymers and terpolymers used according to the invention compared to conventional products are firstly the very good stabilizing properties of the building material systems or water-based paint and coating systems produced correspondingly and secondly the fact that the viscosity of the systems is barely increased, so that these have excellent processability.

Abstract: A fluidising admixture for use with sprayable cementitious compostions, the admixture consists of 2-phosphonobutane-1,2,4-tricarboxylic acid and at least one selected polymer derived from ethylenically-unsaturated mono- or dicarboxylic acids. Citric acid may optionally be present. The admixture has good fluidising properties and outstanding shelf-life.

Abstract: A defoaming agent for cementitious compositions is provided, which has an excellent defoaming performance and does not segregate when mixed with a high performance AE water-reducing agent to form a single admixture or when diluted in water at the desired concentration, and which has excellent long term storage properties. The defoaming agent for cementitious compositions is obtained by mixing at least a polyethylene oxide derivative and a nonionic defoaming agent wherein the polyethylene oxide derivative has at one end a hydrophobic group with a branched structure and/or an unsaturated bond and at the other end an anionic group.

Abstract: Copolymers based on unsaturated mono- or dicarboxylic acid derivatives, oxyalkylene glycol alkenyl ethers and optionally vinylic polyalkylene glycol or ester compounds are described and also their use as additives for aqueous suspensions based on mineral or bituminous binders, in particular cement, gypsum, lime, anhydrite, or other calcium sulphate-based binders, and based on pulverulent dispersion binders. The copolymers according to the invention impart to the aqueous binder suspensions a very good dispersing and liquefying action with, at the same time, simultaneous excellent processing properties. Moreover, the oxyalkylene glycol alkenyl ethers according to the invention are industrially relatively simple and inexpensive to prepare and need comparatively low initiator concentrations in the copolymerization.

Abstract: The use of polymeric microparticles having a cavity in hydraulically setting building material mixtures is described, from 1 to 100% by volume of the cavity of these microparticles being filled with water. In this way, remarkable concrete resistance to the freezing and thawing cycle is achieved, these microparticles providing improved protection for the concrete from the effects of the freezing and thawing cycle, even at a diameter of from 0.1 to 1 ?m and in doses which are 1 to 2 orders of magnitude lower than those described in the prior art. Moreover, the compressive strength of the correspondingly hardened concrete is substantially improved, which was likewise not foreseeable.

Abstract: The present invention relates to the use of epoxy derivatives which have been prepared by reacting a di-, tri- or tetraglycidyl compound (A) with an optionally unsaturated reactive component (B) consisting of a C8-C28-fatty acid, a C8-C28-alcohol or a secondary C8-C28-amine as additives to cementitious building materials. The epoxy derivatives proposed according to the invention are outstandingly suitable as compositions for preventing or suppressing efflorescence on surfaces of set cementitious building materials and/or for hydrophobing the corresponding cementitious systems. In addition, the cementitious products take up substantially less water owing to the additives proposed according to the invention, with the result that frost damage and rapid rusting of the reinforcing steel can be substantially reduced.

Abstract: Pulverulent polycondensation products are described, consisting of a) 5 to 95% by weight of a polycondensation product based on an aromatic or heteroaromatic compound (A) having 5 to 10 C atoms or heteroatoms having at least one oxyethylene or oxypropylene radical and one aldehyde (C) selected from the group consisting of formaldehyde, glyoxylic acid and benzaldehyde or mixtures thereof, and b) 5 to 95% by weight of a finely divided mineral carrier material having a specific surface area of 0.5 to 500 m2/g (according to BET as specified in DIN 66 131). The pulverulent polycondensation products according to the invention are outstandingly suitable in construction material mixtures in an amount of from 0.1 to 5% by weight, based on the weight of the construction material. The pulverulent polycondensation products have a number of advantages here, such as, for example, excellent storage stability, good liquefying action at low dosage and industrially simple production.

Abstract: The present invention concerns a cement additive containing copolymers comprising one or more constitutional units represented by formula A: (A) R1 is hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 1 to 4 carbon atoms or an aryl group having 6 to 9 carbon atoms; R2 is hydrogen or an alkyl group having 1 to 9 carbon atoms, an alkenyl group having 1 to 9 carbon atoms or an aryl group having 6 to 9 carbon atoms; T is alkylene (including straight-chain and branched alkylene) having 1 to 4 carbon atoms or arylene having 6 to 9 carbon atoms; n is 0 or 1; S1 and S2 are, independently of one another, —OCkH2k— or —OCH2CHR3—, with the proviso that k is 2 or 3, R3 is an alkyl group having 1 to 9 carbon atoms, an aryl group having 6 to 9 carbon atoms; and 6<_m1+m2<_25.

Abstract: The invention relates to carboxylic acid derivatives which are obtained by reacting an unsaturated dicarboxylic acid anhydride (A) with a hydrophobic reactive component (B) that contains at least one group reacting to carboxylic acid anhydrides and has an average molecular weight of 200 to 50,000 Dalton. The inventive carboxylic acid derivatives are excellent as a substance for preventing efflorescences on surfaces of hardened cementitious construction materials and/or hydrophobizing the corresponding cementitious systems. Furthermore, said cementitious products absorb considerably smaller amounts of water as a result of the inventive additives such that frost damage and premature rusting of the reinforcing steel can be significantly reduced.