SU870385A1 - Composition for protecting concrete against corrosion - Google Patents

Description

one

This invention relates to the field of building materials, namely, compositions for protecting building products from corrosion.

A known composition for the protection of building products from corrosion, comprising a 50% aqueous dispersion of polyvinyl acetate (1.

The closest to the invention to the technical essence and the achieved result is a composition for protecting a coating of building products based on bakelite lacquer 2.

However, concrete coated with bakelite varnish or polyvinyl acetate dispersion has insufficient corrosion resistance and crack resistance.

The purpose of the invention is to increase the corrosion resistance and crack resistance of concrete. This is achieved by the fact that the composition for protecting concrete against corrosion, including bakelite varnish, contains an additional 50% polyvinyl acetate aqueous dispersion in the following ratio of components, wt%:

Bakelite varnish 30-50

50% polyvinyl acetate water

dispersion. 50-70

Bakelite varnish is a solution of resole-type phenol-formaldehyde resins in ethyl alcohol with the addition of a plasticizer.

To obtain the proposed composition, a bakelite varnish with a viscosity of 40-60 s and a 50% polyvinyl acetate dispersion are taken. Bakelite varnish is poured into the sky polyvinyl acetate dispersion in 10 portions with constant stirring, then water is added to the resulting mass and the mixture is brought to a viscosity of 60-80 seconds.

The proposed composition is applied to #J

15 surface of concrete in any of the known ways: spray gun; brush, roller.

Examples of specific performance are given below, wt.%:

20

Component1 2

thirty

Bakelite lacquer 50 40

25

50% polyvinyl: water acetate

70

60 Dispers 50

Claims (2)

The proposed composition is applied to 30 concrete samples by brush in layers. The thickness of the protective coating layer is 200 microns. Concrete samples covered with the proposed composition are dried in conventional fishery at 18-20 ° C or heated to a temperature at which the concrete retains its properties. The physicomechanical indicators of concrete samples covered with the proposed composition and known are given in the table. Note: The content of the solution of the samples before aging in chlorine is 0.04%. The coating on the basis of the proposed composition is about 65-70 times greater than the crack resistance of a coating with bakelite lacquer, retaining good chemical resistance to aggressive media and adhesion to the protected surface of the product. The advantages of such a composition are also that it does not require difficult conditions for drying the coatings. In addition, the proposed brick, in contrast to the known, can be effectively used to protect the surfaces of concrete building products and will increase the reliability and service life of building structures by about 25-30%. Saving on the restoration of the protective coating on the basis of the proposed composition instead of the 50-year-old building known for the service life will amount to approximately 224 rubles per 100 m of the surface to be protected. Claims of the Invention corrosion resistance and crack resistance of concrete it contains an additional 50% polyvinyl acetate aqueous dispersion, in the following ratio of components, wt.%: Bakelite eli varnish 30-50 50% polyvinyl acetate aqueous dispersion Sources iyu50-70 informatsi.i, received in vnshlanie under examination 1.Polimernye solutions and plastbetony. M., 1967, p.127. 2. Erkenova M.M. and others. Determination of the resistance of protective coatings in chlorine. Proceedings of the Alma-Ata Scientific Research and Design Institute of Building Materials. Issue 12, AA, 1970.