SU1444155A1 - Lubricant for moulds - Google Patents

Abstract

The invention relates to the building materials industry and precast concrete, namely, lubricants for molds and formwork in the manufacture of autoclaved reinforced concrete products. The purpose of the invention is to reduce the adhesion of concrete to the form and ensure hydrophilization of the concrete surface. Form lubricant contains, wt. & / O: machine oil 40-60; carbon-hydrogen resin based on a secondary fraction of the CJ fraction of the petrochemical synthesis of isoprene 5-20; milk of lime else. The adhesion of concrete to the form metal after 5 cycles of autoclave treatment is 18.5–20 kgf / m, the absorption time of the water droplet is 42–100 s. 2 tab. (R (L

Description

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and ioiVu; ciii Ogiosit to industrial - Til (. i i f.: i.: ii, i. materials and prefabricated - ie; i) 6c n) ii ;. namely, the composition of lubricants for (rome and Dii -: -., side, 11 mainly used in the manufacture of concrete and reinforced concrete products autoclaved.

The purpose of the invention is to reduce the adhesion of concrete to form and to ensure hydrophilization of the concrete surface.

The form lubricant contains machine oil, a hydrocarbon resin based on the side C5 fraction of the petrochemical synthesis of isoprene and milk of lime at the following ratio in May / about:

Engine oil 40-60

Hydrocarbon

resin5-20

Lime milk Rest

The hydrocarbon resin (HCV) used to obtain the proposed lubricant is synthesized in the production of synthetic rubber by oligomerizing the secondary Cs fraction in a solution of white spirit in the presence of a modified Friedel Crafts catalyst. The resulting product is a cooligomer of medium unsaturated hydrocarbons, wt.%:

Isoprene 0.5-7.5

Isoamylenes1.0-7.0

Cyclopentadiene 0.3-3.0

Piperylene

After the oligomerization process is completed, the solvent is removed in a vacuum with heating. The final product may contain up to 15% w / w of residual solvent. The latter does not degrade the quality of the lubricant, but, in turn, provides for the elimination of the operation of heating the lubricant during its preparation by reducing the viscosity.

The main characteristics of the used hydrocarbon resin;

Molecular weight 700-1200

Iodine number, g

УЮОг160-210

The lubricant preparation is carried out in the following sequence.

The required amount of engine oil and hydrocarbon resin is added to a vessel equipped with a stirrer and a source of heating, heated to 25-40 ° C and stirred for 5-10 minutes until a homogeneous mixture is obtained, then the specified amount of milk of lime is added to the resulting solution and mixed again 10-15 minutes until a homogeneous emulsion is formed. The resulting lubricant is applied to the surface of the mold using any of the known methods (brush, brush, cloth, roller or using spraying devices), after which concrete mass is poured into the mold. At the same time, the presence of a hydrocarbon resin as a component of a lubricant makes it possible to obtain a lubricant having good adhesion to vertical surfaces.

five

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five

0

five

0

five

0

five

t mi form (sides) and increased resistance to washing with a solution of aerated concrete

mixes.

An example. A container equipped with a preheating source and an agitator with a rotation speed of 220 rpm is loaded (based on prepared 100 kg of finished lubricant) 55 kg of engine oil and 5 kg of hydrocarbon resin.

The mixture is heated to 30 ° C with stirring for 10 minutes until a homogeneous solution is obtained, into which 40 kg of milk of lime is then introduced and mixed again for 10 minutes until a homogeneous emulsion is obtained. The prepared lubricant has a viscosity of 60 s at 20 ° C according to VZ-4, which makes it possible to transport it through pipelines from mechanized posts of preparation to the place of application to the surface of the forms. Using a spraying device, the lubricant was applied to steel molds to make short-haul copper concrete materials of acto-clav hardening. After pouring into the forms of the concrete solution and autoclaving at 8 atm according to the 2 + 8 + 2 h mode, the products were disintegrated (composition 5, Tables 1 and 2)

Example 2. A container equipped with a broom, with a rotation speed of 200 rpm, load (based on the preparation of 100 kg of finished lubricant) 40 kg of engine oil, 10 kg of a 90% aqueous solution of hydrocarbon resin in white spirit and stirred for 5 minutes until a homogeneous solution is obtained, into which 50 kg of milk of lime is then added and mixed again. The lubricant obtained has a viscosity of 55 s at 20 ° C, which allows it to be transported through pipelines from mechanized preparation stations to the places of application to the surface of the molds (composition 8, Tables I and 2).

In tab. Table 1 shows the different formulations of the proposed and known lubricants, for which viscosity tests, concrete adhesion to the molds and the hydrophilicity of the surface of concrete products were carried out.

In tab. 2 shows the results of the test, the composition of the lubricants according to table. one.

Compared with the prototype, the proposed lubricant allows to significantly reduce the adhesion of concrete to the molds and to obtain a hydrophilic surface of products from autoclaved concrete. The use of a hydrocarbon solution in white spirit reduces energy consumption by eliminating the heating of components.

The proposed lubricant with an UVS-based organic additive is frost-resistant: after freezing in a freezer at -12 ° C for 12 hours and subsequent defrosting, it fully retains its original properties.

(comp. 9, Table 2). In addition, in order to save engine oil, used engine oil is allowed without sacrificing lubricant quality (composition 7, Tables 1 and 2).

The proposed lubricant provides the hydrophilicity of the concrete surface, in the resulting products there is no pulverized layer, the thinness of the surface layer and other defects (shells, chips). This allows refusing such a technological operation as cleaning the concrete surface to be trimmed, and also reduces the consumption of surfactants introduced into the aqueous finishing compositions to improve the wetting of the concrete surface. Thus, the use of a hydrocarbon resin in the lubricant as an organic additive improves the surface quality of the concrete, thereby reducing production costs.

one

(prototype) 52

40 50 60 55 40 40

40 40

42

35

65

20

15

ten

five

ten

ten

10 10

20 20 10

0

five

on the cleaning of forms and the subsequent finishing of concrete and reinforced concrete products.

Claims (1)

Invention Formula Lubricant for forms and formwork in the manufacture of concrete and concrete autoclaved products, including engine oil, milk of lime and organic additive, characterized in that, in order to reduce the adhesion of concrete to the form and ensure hydrophilization of the concrete surface, it contains hydrocarbon resin based on the secondary Cd fraction of petrochemical synthesis of isoprene in the following ratio, wt.%: Engine oil 40-60 Hydrocarbon resin5-20 Lime milk Rest Table 1 30 40 35 30 40 50 50 50 50 38 45 25 Used machine oil 90% solution UVS in white alcohol After cycle freeze defrost 24 180 90.0 Continued table. one Table 47 Gray dust layer on the surface, separate dark spots, spot welds of concrete No defects on the concrete surface Also 13 125 15.2 Less than 24 45 23.0 41 45 20.5 41 Continued table. 2 47.5 45.0 53.6 Small yellowish spots on the side PS - the surface of the sample. Point npiiivin :; oston