SU1571041A1 - Composition for applying on fresh-laid concrete - Google Patents

Abstract

The invention relates to building materials and can be used to protect fresh concrete from dehydration and overheating of its surface layers by solar radiation in the process of natural hardening of concrete and reinforced concrete products and structures. The purpose of the invention is to increase the diffuse reflectance of solar radiation, to hydrophobize the surface and reduce the water absorption of concrete. Composition for application to fresh concrete includes the following components, wt%: 30-65% water dispersion of rubber 0.5-25.0

a byproduct of the dewaxing of oils based on solid hydrocarbons - slop-wax or distillate slack 16.5-43.4

technical stearin 1,5-2,5

triethanolamine 0.8-1.7

polyvinyl alcohol 0.1-0.9

polyethylsiloxane fluid 1,3-11,0

water the rest. The coefficient of diffuse light reflection of concrete reaches 78-84%

water absorption - 4-5%. 2 tab.

Description

VI

The invention relates to building materials and can be used to protect fresh concrete from dehydration and overheating of its surface layers by solar radiation in the process of natural hardening of concrete and reinforced concrete products and structures.

The purpose of the invention is to increase the diffuse reflection coefficient of solar radiation, surface hydrophobization and reduction of water absorption of concrete.

The composition for application to fresh concrete includes the following components, wt%:

30-65% water dispersion of rubber. By-product of oil dewaxing based on solid hydrocarbons - slop-wax or distillate distillate

Technical stearin Triethanolamine Polyvinyl alcohol

Polyethylsiloxane

0.5-25.0

16.5-43.4

1.5-2.5 0.8-1.7

0.1-0.9

fluid1,3-11,0

WaterEverything

Slop-vox and distillate (paraffin) slack (TU 3800 1299-78, TU 38 3049-81) of grade No. 1-6 are a mixture of mineral oil and soft paraffins with a pour point of 14-32 ° C and a melting point of 30 -49 ° C. The content of mineral oil in slop-wax is 25–50%, and in ga 1 - 30%. The slop vox is mainly burned with boiler and diesel fuel.

As a divinyl styrene latex, the composition contains either 45% SKS-65 GP latex, or SKS-50 KGP 55% latex, or SKS-50 GP 50% latex, or SKS-C 65% latex. SCS-30 45% latex, or BS-30 35% latex (GOST 11808-78), or BS-50 45% latex (GOST 15080-77) or BS-85 (TU 3.8-UZ- 229-78). As a natural latex, the composition contains 55-60% latex of the Qualtex, Revertex or Revultex brand.

Polyethylene hydridesiloxane hydrophobic liquid 136-41 (GLC-94, GKZH-94M) according to GOST 10834-76 contains the composition KE-30-04 or KE-30-11 in the form of an aqueous 50% emulsion (TU 6-02-816 -78) with an emulsifier solvent - polyvinyl alcohol, the content of the latter in the emulsion is 4 wt.% 0

The composition is prepared as follows.

The slab-vox or distillate sachet is preheated to melt the paraffin contained in it, averaged by stirring the resulting melt using paddle mixers or emulsifiers or dispersants, then the melt is dispersed in hot (55-75 C) water in the presence of an emulsifier — a mixture of stearin with triethanolamine and in the form of a ready-made 25-50% dispersion, after it is cooled to 15-20 ° C, is mixed with the calculated amounts of latex and silicone emulsion EC 30-04. The viscosity of the composition, measured on a VZ-1 funnel, is 20-40 sec.

The composition is applied to the exposed surfaces of freshly laid concrete by a spray method, for example, pneumatic, airless, etc., with

ten

five

20

25

5710414

air temperature 1 - 50 ° С. The time required for the formation of a vapor-tight reflective film on freshly ground concrete is 2 to 8 hours, depending on the temperature and relative humidity of the medium. The consumption of the composition to cover samples of 0.22 - 0.35 kg / m2.

Concrete samples — cubes with an edge of 0.1 m are prepared by vibropressing from a cement-sand mixture of composition, kg / m3: Voskresensky cement M400 680; sand 1530; water 204 liters. After production, the samples are immediately disassembled. A film-forming protective layer from the composition of the prototype (for comparison) and the proposed composition is immediately applied to the exposed surfaces of the samples. Samples harden in air (c) at 17-25 ° C and c) 54-89%, and also subjected to drying (BP) at 48 ± 2 ° C according to the mode: (1.5-2) + 2 + (2- 3) + 1.5 hours. Control samples without coating harden under normal conditions (EX) at 18 - 25 ° C and relative air humidity q 98-100%. At the age of 1 and 28 days, in the samples, by weighting, water loss (dW,%) as a percentage of the initial weight of the mixing water is determined, tested for stretching during splitting (Rp.p) and water absorption (W,% ). The lighting characteristics of the surface of a concrete coating are evaluated with a FB-2 photoelectric gloss meter. The diffuse reflection coefficient (K,%) of the directional light flux from the surface of the coating (whiteness) is determined as a percentage of the diffuse reflection of light from the polished surface of milky-white glass, the reflection coefficient of which is taken as 100%.

Examples of the composition are given in table.1.

The physicomechanical and lighting characteristics of samples protected from dehydration with compositions (C-28 days) are given in Table 2.

During solar heating at an air temperature of 26-30 C, the concrete plate protected by the prototype composition with a cd of 25-31% has a daily

thirty

35

40

45

50

temperature difference on the surface is 55 from 16 to 22 ° С, and is protected by the proposed composition with

KA 72-84% has a temperature difference of only from 8 to 12 ° C. High vapor and heat protection

515

The ability of the developed composition prevents moisture and thermal deformations of freshly laid concrete during its hardening in adverse environmental conditions with low relative humidity and intense solar radiation. Formation of a completely white coating on freshly laid concrete,

protected by the proposed composition is the result of complex chemical interactions developing between triethanolamine stearate (emulsifier of slop-woven), polyethylsiloxane and PVA (emulsifier GKZH-94) and the liquid phase of hardening cement stone (concrete) .On the infrared spectrum, this tumor corresponds to characteristic

absorption band frequencies with maxima of 3380, 2175, 1810, 1550, 1260, 1090, 980, 728, 515 cm-1. For film stabilization of crystals of the indicated neoplasm on the surface of the concrete, latex is introduced into the composition.

Formula of invention

Composition for application to fresh concrete, including. 30-65% aqueous dispersion of rubber, a dewaxing byproduct

Water dispersion

30% piperyl styrene latex

LPS-50

45% Divinnles Latex

SKS-65 GK25

60% natural latex Qualitex

By-product of dewaxing oils based on solid hydrocarbons

Petrolatum3,

Slope Vox25

Distillate gachEmulgator

Production waste

lanolin acid

wool fat3

Soda Ash 2 Stearin Technical Triethanolamine

0

five

0

I

oils based on solid hydrocarbons - slophox or distillate slack, emulsifier, surfactant and water, which, in order to increase the diffuse reflectance of solar radiation, hydrophobization of the surface and reduce water absorption of concrete, it contains emulsifier technical stearin and triethanolamine, as a surfactant - polyvinyl alcohol and additionally polyethylhydride-siloxane liquid in the following ratio, wt.%:

30-65% water

rubber dispersion 0,5-25,0

Byproduct

dewaxing

oil based

solid hydrocarbons - slop-vox

or distillate slack 16.5-43.4

Technical

stearin 1,5-2,9

Triethanolamine 0.8-1.7

Paul Willow

spir0,1-0,9

Polye tilhydridesiloxanova

liquid

Water

Spreadsheets

1.3-11.0

The rest a 1

25

0.510.2

3.0

10.5

16.5

43.4

35.0 20.8

21, 6

1.5 0.8

2.9 1.5

2.5 1.7

1.9 I, 0

2.1 G, 1

Surface-active substance:

1.5

Note. Sample age 28 days. In particular, the characteristics of air-cured concrete, in the denominator, are the characteristics of concrete subjected to non-steam heating at 48t. ° C (1.5-2 + 2 + 2-3 + 1.5 h) and then stored in air.

Continuation of table 1

Claims (1)

Claim Composition for applying to freshly laid concrete, comprising I '30-65% aqueous dispersion of rubber, a byproduct of dewaxing oils based on solid hydrocarbons - slop-vox or distillate pump, emulsifier, surfactant and water, characterized in that that, in order to increase the coefficient of diffuse reflection of solar radiation, hydrophobize the surface and reduce water absorption of concrete, it contains technical stearin and triethanolamine as an emulsifier, and polyvine as a surfactant hydrochloric alcohol and, additionally, polyethyl hydride siloxane liquid in the following ratio of components, wt.%: 30-65% aqueous rubber dispersion A byproduct of the dewaxing of oils based on solid hydrocarbons is slop-vox or distillate Technical stearin Triethanolamine Polyvinyl alcohol Paliethyl hydridesiloxane liquid water 0.5-25.0 gach 16.5-43.4 0.1-0.9 1.3-11.0. Rest Table 1 Components The content of components, wt.%, In the composition Prototype Proposed 1 2 1 3 j 4 | 5] 6] 7 .___-_______________ | --------- 1 ---------- 1_________J________ 1___ Water dispersion kau chuka 30% piperylestiral latex LPS-50 45% divic - ^- - - 25 styrene latex SKS-65 GK. 25 0.5 10,2 60% Natural Qualitex Latex 3.0 10.5 By-product of dewaxing oils on solid hydrocarbon base Petrolatum 3,5 - - - - - - Slop vox 25 34.8 16.5 43,4 - - 21, 6 Distillate Gach - - - - 35.0 20.8 - Emulsifier Production waste lanolin acid wool fat 3 - - - - - - Soda ash 2 - - - - - - Technical stearin - 2.6 1,5 2.9 2,5 1.9. 2.1 Triethanolamine - 1.7 0.8 1,5 1.7 1,0 G. 1 Continuation of table 1 - Components' Component Content wt.%, in the composition Prototype Proposed t 2 1 ' .AND. Surface active substance: RSOg-Na Sulfonate 1,5 Polyvinyl alcohol - · 0.9 0.1. 0.5 0.3 eleven Poly type hydr id forces ok- high liquid 136-4 * 13.0 1 1, 0 1.3 6.0 3.2 1 3.0 (GKZH-94) Water 40,0 47.9 66.3 50.3 44.1 47.8 50.6 table 2 ------------, Indicator Composition - Prototype 1 ----------- Proposed * 1 ' 1 > 1 6 Diffuse reflectance of concrete surface, K _d ,% 25-34 30-36 78-84 45-52 78-82 57-66 72-78 _5χ3__ 6.0 3.8 _4 _L 5__ 4.7 __4χ4_ 3.9 4.0 4.6 4 _A 9 , Open integral porosity, 3.4 4.1 5.2 Moisture loss from 23 19 22 thirteen 16 18 28 concrete by weight of mixing water, 4W,% 44 36 29th 34 ~ 37 ~~ “43“  The limit is durable ty tensile _2 _± 6_ 7 6 S 3χθ _2χΖ_ 2.6 2.6 _2χ4__ 2,3 when cracking, R. ₀ , MPa 2,5 * and 2,5 2,8 Color and Condition Dark ^ .surface gray concrete Gray Snow white Gray white Snow white White White Note. The age of the samples is 28 days. In the numerator, the characteristics of concrete are air hardening, in the denominator are the characteristics of concrete subjected to steam-free heating at 48t2 ° C (1.5-2 + 2 + 2-3 + 1.5 h) and then stored in air.