Abstract:
The present invention pertains to a process for the preparation of aqueous dispersions which are stabilized with a water-insoluble stabilizing colloid, characterized in that a) in a first step a water-insoluble stabilizing colloid is prepared, with this being prepared, based on the amount of monomer used for the preparation of the stabilizing colloid, by means of radical polymerization, followed by b) the addition of at least one further olefinically unsaturated monomer and at least one initiator, in which process by means of radical polymerization of the further olefinically unsaturated monomer an aqueous dispersion is obtained, on which c) optionally a residual monomer reduction is performed, with this being carried out by means of polymerization of residual monomers and/or by means of physical removal of the residual monomers and optionally further volatile organic components by means of the introduction of vapor and/or gas.
Abstract:
The invention relates to an aqueous dispersion and dispersion powder composition for highly flexible, waterproof, hydraulically binding tile adhesives having an extended open time, and containing an emulsion polymer (A) having a glass transition temperature (Tg) of approximately 10° C. to 80° C., and an emulsion polymer (B) having a glass transition temperature (Tg) of approximately −60° C. to +20° C. The difference of the glass transition temperatures (Tg) of the emulsion polymers (A and B) is at least approximately 5° C. The proportion of vinyl acetate monomer units is 0 to 70 mol-% and the minimum film forming temperature according to DIN 53787 of the 50% aqueous dispersion composition is approximately 15° C. or less, and the monomers, stabilization systems and optionally the additional additives of the dispersion and/or dispersion powder composition are selected such that a good cement compatibility is guaranteed. Due to the inventive dispersion and dispersion powder composition, tile adhesive can be produced in an economical manner which meets the requirements of C2S2- and C2ES2-norm according to EN12004.
Abstract:
The present invention pertains to a water-redispersible polymer powder based on at least one modified natural latex. The modified natural latex can be obtained by mixing natural latex with at least one radical initiator and/or oxidizing agent, by mixing and reacting natural latex with at least one olefinically unsaturated monomer and with at least one radical initiator, and/or by mixing natural latex with at least one filler. Preferably, the polymer powder contains up to about 95 wt. % of least one natural latex, about 0 to 50 wt. % of at least one protective colloid, about 2 to 70 wt. % of at least one filler and/or anti-caking agent, as well as optionally further additives. In addition, the invention pertains to a process for the preparation of the polymer powder, the use thereof as an additive in building material compositions, as well as building material compositions containing the polymer powder.
Abstract:
The present invention pertains to a process for the preparation of aqueous dispersions which are stabilised with a water-insoluble stabilising colloid, characterised in that a) in a first step a water-insoluble stabilising colloid is prepared, with this being prepared, based on the amount of monomer used for the preparation of the stabilising colloid, by means of radical polymerization of a1) about 1 to 90 wt. % of at least one olefinically unsaturated monomer, containing at least one sulfate and/or sulfonate group, which optionally may be protonated, a2) about 5 to 99 wt. % of at least one olefinically unsaturated monomer with a water solubility at 20° C. of less than 50 g/l, and a3) up to 50 wt. % of at least one olefinically unsaturated monomer with a water solubility at 20° C. of more than 50 g/l, in water, followed by b) the addition of at least one further olefinically unsaturated monomer and at least one initiator, in which process by means of radical polymerization of the further olefinically unsaturated monomer an aqueous dispersion is obtained, on which c) optionally a residual monomer reduction is performed, with this being carried out by means of polymerization of residual monomers and/or by means of physical removal of the residual monomers and optionally further volatile organic components by means of the introduction of vapour and/or gas. The dispersions obtained in this manner can be converted into water-redispersible polymer powders with the aid of drying. Moreover, the invention pertains to the use of the water-insoluble stabilising colloid, the dispersion, and the water-redispersible polymer-powder.
Abstract:
The present invention pertains to a dry cement formulation for cementing earth boreholes, in particular oil, gas and/or terrestrial heat boreholes, containing a) about 20 to 99.9 wt. % cement, b) about 0 to 65 wt. % powdered quartz/or quartz dust, c) about 0.1 to 30 wt. % water-redispersible dispersion powder, and d) about 0 to 20 wt. % further additives. Furthermore, the invention pertains to the use of the dry cement formulation for preparing a cement slurry as well as to the use of water-redispersible dispersion powders in a cement slurry for cementing earth boreholes, wherein the cement slurries can be used for reducing the water loss of the cement slurry, for reducing the gas and/or water penetration and/or for sealing off the gas and/or water channels by means of the cement slurry which has been introduced into the borehole and has set.
Abstract:
The present invention relates to the use of an additive as well as a process to improve the adhesion of a mortar to a building substrate, wherein the mortar is mixed with said additive and is applied to a building substrate selected from the group of polystyrene-containing substrates, polyolefin-containing substrates or polyvinyl chloride-containing substrates, the additive containing (i) a plasticizer that is liquid at 50° C. or lower, has a boiling point of 100° C. or higher, and that has a solubility parameter δ 25° C. between 22.5 MPa1/2 and MPa1/2; (ii) optionally, a filler that has a BET surface area of at least 40 m2/g; (iii) optionally, a biopolymer, (iv) optionally, a protective colloid; and (v) optionally, a water-insoluble film-forming (co)polymer based on ethylenically unsaturated monomers. The invention also covers an additive and a kit of parts suitable for use in the above process.
Abstract:
The invention relates to a redispersible powder obtainable by (co)polymerization, using a polymer with cationic functionality in an aqueous medium, optionally accompanied by the use of conventional additives, the polymer with cationic functionality being obtained by (co)polymerization in an aqueous medium of olefinically unsaturated (co)monomers, wherein at least one (co)monomer has a cationic functionality, further (co)monomers are added and polymerization takes place in the presence of suitable initiators, and by drying the aqueous dispersion obtained, the (co)polymerizate having one or more reactive groups. According to another embodiment, the polymer with cationic functionality is formed in situ in the presence of a seed. According to another embodiment, the process is controlled in such a way that a (co)polymerizate particle with heterogeneous morphology is formed. The invention also relates to the aqueous dispersions, a process for the preparation of the redispersible powder and the use thereof.
Abstract:
The invention relates to a process for the preparation of aqueous dispersions of latex particles having a heterogeneous morphology by a semicontinuous emulsion polymerization, comprising the emulsion polymerizing of ethylenically unsaturated (co)monomers, accompanied by, the addition of cationic and/or anionic and/or nonionic emulsifiers and/or protective colloids as stabilizers, which are directly used as such or synthesized in situ, the semicontinuous emulsion polymerization being performed in the presence of the stabilizer or stabilizers with a monomer mixture, which a) contains at least one nonionic, ethylenically unsaturated monomer with a glass transition temperature Tg above about 30° C. in a quantity of about 10 to 70 wt. %, based on the total weight of ethylenically unsaturated (co)monomers and b) at least one hydrophilic, ethylenically unsaturated monomer in a quantity of about 5 to 30 wt. %, based on the total weight of ethylenically unsaturated (co)monomers.
Abstract:
The invention relates to an aqueous dispersion and dispersion powder composition for highly flexible, waterproof, hydraulically binding tile adhesives having an extended open time, and containing an emulsion polymer (A) having a glass transition temperature (Tg) of approximately 10° C. to 80° C., and an emulsion polymer (B) having a glass transition temperature (Tg) of approximately −60° C. to +20° C. The difference of the glass transition temperatures (Tg) of the emulsion polymers (A and B) is at least approximately 5° C. The proportion of vinyl acetate monomer units is 0 to 70 mol-% and the minimum film forming temperature according to DIN 53787 of the 50% aqueous dispersion composition is approximately 15° C. or less, and the monomers, stabilization systems and optionally the additional additives of the dispersion and/or dispersion powder composition are selected such that a good cement compatibility is guaranteed. Due to the inventive dispersion and dispersion powder composition, tile adhesive can be produced in an economical manner which meets the requirements of C2S2- and C2ES2-norm according to EN12004.
Abstract:
The present invention pertains to a water-redispersible polymer powder composition based on at least one synthetic polymer and at least one natural latex. Preferably, the polymer powder contains up to about 90 wt. % of at least one water-insoluble, synthetic polymer, up to about 90 wt. % of least one natural latex, about 0 to 50 wt. % of at least one protective colloid, about 2 to 50 wt. % of at least one filler and/or anti-caking agent, as well as optionally further additives. In addition, the invention pertains to a process for the preparation of the polymer powder composition, the use thereof as an additive in building material compositions, as well as building material compositions containing the polymer powder composition.