Additive building material mixtures containing different-sized microparticles

Abstract

The present invention relates to the use of different-sized polymeric microparticles in hydraulically setting building material mixtures for the purpose of enhancing their frost resistance and cyclical freeze/thaw durability.

Description

Claims

1. Use of polymeric microparticles, containing a void, in hydraulically setting building material mixtures, characterized in that different-sized microparticles are used.

2. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that mixtures of microparticles having a diameter of between 100 nm and 150 μm are used, at least one of the types of microparticles present in the mixture having a diameter of less than 1000 nm.

3. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that at least one type of the microparticles are composed of polymer particles which comprise a polymer core (A), which is swollen by means of an aqueous base and contains one or more unsaturated carboxylic acid (derivative) monomers, and a polymer envelope (B), which is composed predominantly of nonionic, ethylenically unsaturated monomers.

4. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that at least one type of microparticles are composed of gas-filled polymer particles having a diameter of more than 10 μm and at least one further type of microparticles in the mixture has a diameter of less than 1000 nm.

5. Use of polymeric microparticles, containing a void, according to claim 3, characterized in that the unsaturated carboxylic acid (derivative) monomers are selected from the group of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid and crotonic acid.

6. Use of polymeric microparticles, containing a void, according to claim 3, characterized in that the nonionic, ethylenically unsaturated monomers are composed of styrene, butadiene, vinyltoluene, ethylene, vinyl acetate, vinyl chloride, vinylidene chloride, acrylonitrile, acrylamide, methacrylamide, C1-C12 alkyl esters of acrylic or methacrylic acid.

7. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that the microparticles have a polymer content of 2% to 98% by volume.

8. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that the microparticles are used in an amount of 0.01% to 5% by volume, based on the building material mixture.

9. Use of polymeric microparticles, containing a void, according to claim 7, characterized in that the microparticles are used in an amount of 0.1% to 0.5% by volume, based on the building material mixture.

10. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that the building material mixtures are composed of a binder selected from the group of cement, lime, gypsum and anhydrite.

11. Use of polymeric microparticles, containing a void, according to claim 1, characterized in that the building material mixtures are concrete or mortar.