DE1238831B - Process for the production of easily spreadable cement - Google Patents

Description

GERMAN VmWWi- PATENT OFFICE

EDITORIAL DEVELOPMENT DeutscheKl .: 80 b -1/05

Number: 1238 831

File number: K 54977 VI b / 80 b

J 238 831 filing date: January 9, 1965

Opened on: April 13, 1967

The invention relates to a method for the production of easily spreadable cement, in which a Dispersant incorporated in cement and an easily spreadable hydraulic binder mass that used in the manufacture of portland cement, concrete, mortar and casting compounds with excellent strength and processability is obtained. The term "cement" includes silicate cement compounds in the following including portland cement, pozzolan cement, hydraulic limes and natural borne Cements.

It is known that in concrete, mortar and casting compounds that contain a hydraulic binder, the processing properties of such compositions are markedly improved by the use of a dispersant will. The dispersibility of secondary aggregated particles of cement is increased by adding the dispersant is improved, whereby these secondary particles are broken down into primary particles, which leads to an increase in the contact area of the particles and also to an increased strength of the Concrete leads after setting. There have been many types of compounds for use as dispersants suggested, but sodium lignosulfonate has been the most commonly used in practice. It the assumption was also expressed that a naphthalenesulfonic acid derivative-formaldehyde condensate, which is often used as a dispersant for pigments or dyes, also as a dispersant can be used for cement but is not very effective for this purpose.

It has now been found that easily spreadable cement, excellent workability and has very good strength values after setting, can thereby be obtained according to the invention, that as a dispersant in an amount of more than 0.01 percent by weight, based on the Weight of cement, a product mixed in by condensation of naphthalenesulfonic acid derivatives and formaldehyde is produced, this being more than 70 percent by weight of the product Condensates from naphthalenesulfonic acid derivatives and formaldehyde with at least five naphthalene nuclei and less than 8 percent by weight, preferably less than 5 percent by weight, unreacted Contains naphthalene-silicic acid derivatives.

The term "Naphthalinsulfonsäurederivat" refers in the following to naphthalene -u sulfonic acid, naphthalene -p-sulfonic acid and salts thereof, and the term "naphthalene" or derivatives thereof is a sulfonated naphthalene.

In the implementation of 2 moles of naphthalenesulfone process to produce easily distributable cement

Applicant:

Kao Soap Company, Ltd., Tokyo
Representative:

Dr. K. Th. Hegel, patent attorney,
Hamburg 36, Esplanade 36 a

Named as inventor:

Kenichi Hattori, Wakayama (Japan)

acid derivative and 1 mole of formaldehyde, a naphthalenesulfonic acid derivative-formaldehyde condensate is obtained, has the following formula:

SO ₃ M

SO ₃ M

in which the SOsM groups can be in the a or p 'position on the naphthalene nucleus.

The known, commercially available naphthalenesulfonic acid derivative formaldehyde condensates are relatively low molecular weight condensates and consist of a mixture of mononuclear and polynuclear Compounds and can be represented by the following formula:

CH ₂

(II)

where η represents the total number of nuclei and M represents a water-soluble alkali or alkaline earth metal or another metal.

It has now been found that it can be used as a dispersant for the production of easily spreadable cement especially those naphthalenesulfonic acid derivative-formaldehyde condensates which contain

709 549/385

have at least five-nucleus compounds, which is higher than in the usual commercial products and makes up more than 70 percent by weight of the condensates.

In Table I below, the proportions of the various compounds are given in various Products and their dispersion effect indicated:

Table I.

Analysis of naphthalenesulfonic acid-formaldehyde condensates and their dispersion effect on cement

composition
Dispersant single core conn
dung (not vice versa
put naphthalene
sulfonic acid) Connections in
binuclear
link Weight percent
about five-core
Connection (a
finally from
five-core ver
bonds, η 2: 5) Dispersibility
(min) * Commercial product A 9.8 10.0 49.0 12.5 Commercial product B 9.0 8.6 53.4 13.0 Commercial product C 12.0 9.2 52.3 12.0 Synthetic product (test product) .. 12.9 9.8 51.2 12.5 Synthetic product (product A) 2.7 2.0 83.7 170.0 Synthetic product (product B) 2.8 1.9 85.7 150.0 Calcium lignosulfonate 12.5

* The dispersibility (min) indicates the time in minutes required for a 50% sedimentation of a 20 weight percent suspension of Portland cement in water (which contains 0.5 percent by weight of the dispersant based on the weight of the cement) is required.

Products A and B are dispersants as used in the process according to the invention will.

It has been found that such high molecular weight naphthalenesulfonic acid derivative - formaldehyde condensates are excellent dispersants for cement. If such a dispersant is a hydraulic binder is added, the strength of the concrete made from it is excellent. The dispersing effect is significantly increased if such a condensate is high Molecular weight is used, its content of mononuclear naphthalenesulfonic acid derivative compounds is less than 8 percent by weight.

In the method according to the invention, it is advantageous to use the cement together with the dispersant also an air-entrained substance, an agent that promotes hardening, an inorganic one Add electrolytes and, if necessary, a retarder. For example, according to the invention Produce an easily spreadable cement by adding mixtures of substances following the cement interferes:

Weight percent

Dispersant 50 to 99.99

Air entrained material 0.01 to 10

Calcium chloride 0 to 50

Potassium chloride 0 to 50

Delay 0 to 10

or preferably

Dispersants 58.9 to 96.2

Air entrained matter 0.95 to 5.9

Calcium chloride 1.9 to 29.3

Potassium chloride 0.95 to 5.9

Retarder 0 to 10.0

The dispersant used in the process according to the invention can be in the form of spray-dried Powders or as an aqueous 10 to 50 weight percent solution and is used in an amount greater than 0.01 percent by weight, preferably 0.25 to 0.5. Percent by weight, based on the weight of the cement added to it. The substance mixtures listed above, which contain the dispersant are in the cement in an amount of 0.1 to 10 percent by weight, preferably about 0.5 percent by weight, based on the weight of the cement. The mixture of substances can be in the form of a powder, but is usually an aqueous one 10 to 20% solution is mixed in and can be added if necessary while the concrete is being mixed be added.

The term "air entrained material" means surface-active agents that increase surface tension of water in alkaline solution, which are soluble in alkaline solutions and a great deal of degradation Form quantity of gas pores in alkaline solutions by foaming effect. Such effective air entrained substances are for example sodium abietate, denatured abietate, rosin or a potassium salt of rosin, polyoxyethylene nonylphenyl ether, polyoxyethylene sorbitan monooleate or a sodium salt, Ammonium salt or triethanolamine salt of lauryl sulfate.

The term "retarder" means customary additives, such as plaster of paris, which are added to cement masses can be added to delay the setting time of the cement.

example

130 ecm of water were added to 1450 g of Portland cement, which is a water equivalent to Table II below specified amount of dispersant contained, mixed at 20 ± 1 ° C, and the mixture was in a mortar mixer for 1 minute at 60 rev / min. and 2 minutes at 120 rev / min. emotional. the Batches were prepared with the various dispersants indicated in Table II below in the amounts indicated, and the effect of the dispersants on the flow value

the cement produced in this way was tested by placing the respective batch on a flow table for 15 minutes was allowed to leak.

The flow values are given in Table II below.

Table II Table III

Flow value (mm) Dispersant 0.25 ge
weight percent 0.5 Ge
weight percent Dispersions Dispersions middle middle Commercial product A. 182 210 Commercial product B 181 204 Commercial product C 188 206 Synthetic product (Trial product) 181 205 Synthetic product (ProductA) 188 276 Synthetic product (Product B) 193 250 Calcium lignosulfonate 195 206

Air content (volume percentage) Dispersant Weight percent dispersant used 0.125 0.25 0.50 Commercial product A .... 10.5 10.1 10.0 Commercial product B 10.3 10.4 10.2 Commercial product C 11.0 11.2 11.2 Synthetic product (Product A) 6.9 6.5 6.4 Synthetic product (Product B) 6.6 6.4 6.3

The condensation products used in the process according to the invention with more than 70 percent by weight on condensates with at least five naphthalene nuclei (products A and B) show excellent Values.

To check the air content when adding different dispersing agents in different amounts was a mixture of 1040 g standard sand, 520 g Portland cement and water, which is described in the following Table III contained the specified dispersant in one Mortar mixer 1 minute at 60 rev / min. and 2 minutes at 120 rev / min. emotional. The air content of the mortar obtained in this way is given in Table III.

It should be noted that the dispersants used in the process according to the invention (Products A and B) show almost no foaming effect, which is advantageous since the formation of a Foam reduces the strength of the cement product and consequently for many purposes, for example for the production of vaults, pipes or reinforced concrete, is undesirable.

In the process according to the invention, it is possible, if necessary, by adding an air-entrained substance easily form a concrete that contains a suitable amount of air and has good durability and Has freeze-thaw stability, and it is possible in the method according to the invention to introduce the Amount of air regardless of the amount of dispersant used and regardless of to control the dispersing effect, what happens when using conventional dispersants was difficult.

In the following Table IV the composition of two concrete masses is given, their properties were examined comparatively. The results of these tests are shown in Table IVa reproduced.

Table IV Composition of Concrete

preparation
volume Portland
cement
(kg) water
(kg) Finer
Surcharge
(kg) Gi
5 to
10 mm -above add
IObis
20 mm llag
20 to
30 mm Disper
sions
medium to
cement Usually
Mass, the dispersant ent
holds 45.1
45 13.65
12.15 6.03
5.13 16.64
15.73 10.90
11.27 16.35
16.91 27.25
28.22 0
0.03

Table IVa Test results of the concrete

Type of dispersant Water supply
reduction
(%) Drop
(cm) Air content
(%) Usually 6.0 0.85 Commercial product of the lignosulfonate type 13.4 8.0 3.5 Creosote oil type product 13.4 4.5 2.0 Commercial product A 13.4 4.0 2.6 Synthetic product B 13.4 5.0 1.8

Compressive strength (kg / cm ² )

7th day

28th day

244
245
263
260
283

389
374
406
405
432

Claims (3)

As shown in Table IVa, the strength of the concrete made in accordance with the invention was better than that of the ordinary concrete, although the amount of cement used was only about 90% by weight of that used in the ordinary concrete. A standard composition for concrete for dams was also tested in order to determine the effect of the dispersant used in the method according to the invention on the strength of concrete under conditions in which the settling is constant (7.5 ± learn) and the amount of air was constant (3.5 ± 0.5%). Denatured sodium abietate was used as the air-entrained substance together with the dispersant. The examination conditions were as follows: 1. Humidity 90%, atmospheric temperature 15 C, water temperature 15 "C, concrete temperature 17" C un ^ kneading time of the concrete 4 minutes. 2. Materials: Speci
fish
weight surfaces
water
(° / o) Delicacy
module
C '/ o) cement 3.15 Fine surcharge 2.6 1.0 2.94 Gross surcharge 2.6 dried The term "fineness modulus" is the percentage expression of a sum of residues in Sieving, if sieve tests using sieves with openings of 80, 40, 20, 10, 5, 2.5, 1.2, 0.6, 0.3 and 0.15 mm. 3. Compositions Type of dispersant !
Unity unity
weight weight
of water _i of cement
(kg) ¹ (kg) WZ
(%) SA
<"..) S.
(kg) K
(kg) Encore
relationship water
min-
change
relationship
(%) 1. Ordinary 140 300 44.6 37 726.1 1236 2. Commercial product of the creosote type .. 121.6 270 45.11 35 693.8 1288.5 0.25 13th 3. Synthetic product A. 121.8 270 45.11 35 693.8 1288.5 0.25 13th 4. Product A - natural resin soap (2.5%) 119 270 44.07 35 698.8 1294 0.25625 15th 5. Product A - natural resin soap (5%) .. 119 270 44.07 35 698.8 1294 0.0625 15th 6. Product B - natural resin soap (2.5%) 119 270 44.07 35 698.8 1294 0.25625 15th 7. Commercial product of the lignin type ... 119 270 44.07 35 698.8 1294 0.25 15th A = S - K, W = unit of water, Z = unit of cement, S = sand, K = gravel. The unit weight of water and the unit weight of cement are the weights of water and cement per 1 m ^{3 of} concrete. 601 concrete were produced from each of the compositions listed under 3. The at the The results of testing these concrete batches are given in Table V below : Table V Test results of the concrete Settling Lutta content ¹ compressive strength (kg cm =) ^Nr - i, (cmt ("») 7th day, 28th day 1. 7.5 1.0 i 214 381 8.0 3.55 i 200 ¹ 340 3. 7.5 2.15 243 375 4th 6.5 3.25 265 ι 390 5. 7.5 3.35 263 ¹ 375 6th 7.0 3.6 ; 234 362 7th 8.0 : 3.4 I 190 320 6o 65 From the results of these tests it can be seen that the manufactured according to the invention Cement-made concrete has excellent green strength. Patent claims: 1. A method for the production of easily spreadable cement by adding a dispersing agent, characterized in that that as a dispersant in an amount of more than 0.01 percent by weight, based on the Weight of the cement, a product mixed into the cement made by condensation of naphthalenesulfonic acid derivatives and formaldehyde is produced, this product being more than 70 percent by weight the condensates of naphthalenesulfonic acid derivatives and formaldehyde with at least five naphthalene nuclei and less than 8 percent by weight, preferably less than 5 percent by weight, Contains unreacted naphthalenesulfonic acid derivatives. 2. The method according to claim 1, characterized in that together with the Dispersant an air entrainment material in an amount of 0.01 to 10 percent by weight, preferred 1 wise 0.95 to 5.9 percent by weight, based on the weight of dispersants, and optionally 0 to 50 percent by weight, preferably 1.90 to 29.3 percent by weight calcium chloride, 0 to 50 percent by weight, preferably 0.95 to 5.9 weight percent potassium chloride and 0 to 10 weight percent retarder in the cement mixed in, the total amount of substances mixed in, based on 0.1 to 10 percent by weight on the weight of the cement.