GB2084129A - Hardening a building material - Google Patents

Abstract

A building material comprising a water hardenable mixture of aggregate and binding agent is hardened by admixing a polymerisate dispersion in place of water. The polymerisate may be a mixed polymerisate of vinylidene chloride and vinyl chloride or it may be polyacrylonitrile.

Description

SPECIFICATION A method of hardening a building material The present invention relates to a method for hardening a building material for floors, ceilings and walls, such as concrete, plaster flooring, plaster of Paris and the like, the binding agents, for example cement, and aggregates, for example sand, of which are hardenable by water.

The properties of the above-mentioned building materials are limited. Attempts to significantly improve such materials have had little success.

According to the present invention there is provided a method of hardening a building material comprising a water hardenable mixture of aggregate and binding agent, the method comprising the step of admixing a polymerisate dispersion with the mixture in lieu of water.

A building material hardened by a method exemplifying the present invention may exhibit improved impact resistance, resistance to wear, chemical constancy and impermeability to water, while its tendency to shear under bending stress and chemical absorption may substantially be lowerthan in the case of known building materials.

During hardening, any water in the polymerisate dispersion, for example if an aqueous dispersion, is removed. Through the removal of the water, the polymers form a closed film which encloses the remaining components of the building material, i.e.

binding agents and aggregates, so that a contiguous polymer structure with embedded building material components results. In this resides the substantial improvement in the properties of the building material.

Particularly good results in respect of chemical constancy and impermeability to water may be achieved if an aqueous dispersion of mixed polymerisate of vinylide chloride and vinyl chloride is used as the polymerisate dispersion. For a building material hardened with the application ofthis feature, an increase in mass of less than 3% may result from immersion in Diesel fuel, atomisable fuel and water for four weeks, and between 10% and 12% for conventional plaster flooring.

Equally good results, however, with greater heat resistance of the building material may be achieved if an aqueous polyacrylnitrile dispersion is used as the polymerisate dispersion. It is also possible to use a compound of a mixed polymerisate of vinylide chloride and vinyl chloride as well as of a polyacrylnitrile dispersion.

Expediently, the solid content of the polymerisate dispersion is between substantially 40% and 70%, and the mean particle size of the solid substance of the polymerisate dispersion is no more than substantially 0.8 microns.

In an example of the method according to the invention, the ratio of the polymerisate dispersion to the remaining components.of the building material (binding agents and aggregates) is between substantially 1:6 and 1:3. For a cement plaster flooring, which consists of 2.5 parts of Rhine sand and 1 part of cement, 0.6 to 0.9 parts of the polymerisate dispersion are, for example, added according to initial moisture and processing time.

A building material hardened by a method exemplifying the present invention is versatile in its use, for example, it may be used for the formation of workshop floors, catching basins, storage containers, pipes and the like, or for lining containers.

1. A method of hardening a building material comprising a water hardenable mixture of aggregate and binding agent, the method comprising the step of admixing a polymerisate dispersion with the mixture in lieu of water.

2. A method as claimed in claim 1, the dispersion comprising an aqueous dispersion of mixed polymerisate of vinylide chloride and vinyl chloride.

3. A method as claimed in claim 1, the dispersion comprising an aqueous polyacrylnitrile dispersion.

4. A method as claimed in any one of the preceding claims, wherein the polymerisate dispersion has a solids content of substantially 40 to 70 percent.

5. A method as claimed in any one of the preceding claims, wherein the polymerisate dispersion comprises particulate solid material having an average particle size of at most 0.8 microns.

6. A method as claimed in any one of the preceding claims, wherein the polymerisate dispersion is admixed with the mixture in a ratio of substantially 1:6 to 1:3.

7. A method as claimed in claim 1 and substan tally as hereinbefore described.

8. A building method comprising a mixture of aggregate and binding agent hardened by a method as claimed in any one of the preceding claims.

9. A material as claimed in claim 8, wherein the aggregate comprises sand and the binding agent comprises cement.

10. A constructional element comprising at least in part a building material as claimed in either claim 8 or claim 9.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (10)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A method of hardening a building material The present invention relates to a method for hardening a building material for floors, ceilings and walls, such as concrete, plaster flooring, plaster of Paris and the like, the binding agents, for example cement, and aggregates, for example sand, of which are hardenable by water. The properties of the above-mentioned building materials are limited. Attempts to significantly improve such materials have had little success. According to the present invention there is provided a method of hardening a building material comprising a water hardenable mixture of aggregate and binding agent, the method comprising the step of admixing a polymerisate dispersion with the mixture in lieu of water. A building material hardened by a method exemplifying the present invention may exhibit improved impact resistance, resistance to wear, chemical constancy and impermeability to water, while its tendency to shear under bending stress and chemical absorption may substantially be lowerthan in the case of known building materials. During hardening, any water in the polymerisate dispersion, for example if an aqueous dispersion, is removed. Through the removal of the water, the polymers form a closed film which encloses the remaining components of the building material, i.e. binding agents and aggregates, so that a contiguous polymer structure with embedded building material components results. In this resides the substantial improvement in the properties of the building material. Particularly good results in respect of chemical constancy and impermeability to water may be achieved if an aqueous dispersion of mixed polymerisate of vinylide chloride and vinyl chloride is used as the polymerisate dispersion. For a building material hardened with the application ofthis feature, an increase in mass of less than 3% may result from immersion in Diesel fuel, atomisable fuel and water for four weeks, and between 10% and 12% for conventional plaster flooring. Equally good results, however, with greater heat resistance of the building material may be achieved if an aqueous polyacrylnitrile dispersion is used as the polymerisate dispersion. It is also possible to use a compound of a mixed polymerisate of vinylide chloride and vinyl chloride as well as of a polyacrylnitrile dispersion. Expediently, the solid content of the polymerisate dispersion is between substantially 40% and 70%, and the mean particle size of the solid substance of the polymerisate dispersion is no more than substantially 0.8 microns. In an example of the method according to the invention, the ratio of the polymerisate dispersion to the remaining components.of the building material (binding agents and aggregates) is between substantially 1:6 and 1:3. For a cement plaster flooring, which consists of 2.5 parts of Rhine sand and 1 part of cement, 0.6 to 0.9 parts of the polymerisate dispersion are, for example, added according to initial moisture and processing time. A building material hardened by a method exemplifying the present invention is versatile in its use, for example, it may be used for the formation of workshop floors, catching basins, storage containers, pipes and the like, or for lining containers. CLAIMS

1. A method of hardening a building material comprising a water hardenable mixture of aggregate and binding agent, the method comprising the step of admixing a polymerisate dispersion with the mixture in lieu of water.

2. A method as claimed in claim 1, the dispersion comprising an aqueous dispersion of mixed polymerisate of vinylide chloride and vinyl chloride.

3. A method as claimed in claim 1, the dispersion comprising an aqueous polyacrylnitrile dispersion.

4. A method as claimed in any one of the preceding claims, wherein the polymerisate dispersion has a solids content of substantially 40 to 70 percent.

5. A method as claimed in any one of the preceding claims, wherein the polymerisate dispersion comprises particulate solid material having an average particle size of at most 0.8 microns.

6. A method as claimed in any one of the preceding claims, wherein the polymerisate dispersion is admixed with the mixture in a ratio of substantially 1:6 to 1:3.

7. A method as claimed in claim 1 and substan tally as hereinbefore described.

8. A building method comprising a mixture of aggregate and binding agent hardened by a method as claimed in any one of the preceding claims.

9. A material as claimed in claim 8, wherein the aggregate comprises sand and the binding agent comprises cement.

10. A constructional element comprising at least in part a building material as claimed in either claim 8 or claim 9.