JPH01219054A - Dispersant composition for cement - Google Patents

Abstract

PURPOSE:To obtain the subject composition producing a high dispersion effect with an extremely small amt. as compared with the well-known dispersant from a mixture of the phosphoric ester and arylphenol alkylene oxide-added nonionic surfactant respectively shown by a specified formula. CONSTITUTION:The desired dispersant composition for cement consists of 90-10 pts.wt. of the phosphoric ester shown by formula I or its salt (A component) and 10-90pts.wt.of the arylphenol alkylene oxide-added nonionic surfactant shown by formula II (B component). The A component is obtained according to the conventional method by adding an alkylene oxide such as ethylene oxide to the higher alcohols such as hexyl alcohol and the phenols, and then esterifying the addition product with phosphoric anhydride. Meanwhile the B component is obtained by adding alkylene oxide to an arylphenol such as benzylphenol.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a novel dispersant for cement.

More specifically, the present invention is a dispersant for cement, which aims to reduce the unit water content of concrete used for civil engineering and construction, significantly improve workability, and also significantly improve various properties of hardened concrete. be.

[Prior art]

Conventionally, concrete products have been widely used for civil engineering and construction. Cement dispersants improve the dispersibility of cement particles by applying physicochemical effects such as wetting and penetration to cement particles, thereby reducing water consumption, improving workability, and improving strength and durability. It is used for the purpose of improvement.

Typical cement dispersants include anionic surfactants such as lignin sulfonate, naphthalene sulfonate formalin condensate, melamine sulfonate formalin condensate, oxycarboxylate, and nonionic surfactants such as polyol complexes. is also known.

[Problems that the invention attempts to solve]

However, the cement dispersants used hitherto have various drawbacks. For example, lignin sulfonate is obtained from the pulp manufacturing process and has drawbacks such as varying dispersion effects, and naphthalene sulfonic acid formalin condensate salt can be used in small amounts when added compared to other dispersants. Generally, the dispersion effect is small, and melamine sulfonic acid formalin condensates have problems with compatibility when mixed with other admixture components, and oxycarboxylate and polyol-based products exhibit significant curing retardation and retardation when added in large amounts. , indicating poor curing.

As a result of various studies to overcome the drawbacks of current cement dispersants, the present inventors have provided a cement dispersant composition that exhibits a greater dispersion effect with a smaller amount added than conventional cement dispersants. It is something to do.

[Means for solving problems]

The present invention is based on the general formula % formula % (1) [where R1 is a phenyl group, a straight chain or branched alkyl group having 6 to 18 carbon atoms, or an alkylphenyl group or alkenyl having an alkyl group having 8 to 18 carbon atoms] AO represents an ethyl group or an alkylene oxide group consisting of an ethyl group and a propyl group, n represents an integer of 0 to 30, m represents 1 or 2, m x Q represents an integer of 3, and M represents hydrogen or or divalent metal salt, ammonium salt, or N having an alkyl group or alkanol group having 3 or less carbon atoms.
-At least one kind of phosphoric acid ester or its salt represented by 9
0 to 10 parts by weight and the general formula % formula % (2) [However, R1 represents a benzyl group, a styryl group, or a cumyl group, and AO represents an alkylene oxide group in which A is an ethyl group or an ethyl group and a propyl group.

This is a dispersant composition for cement comprising 10 to 90 parts by weight of an arylphenol alkylene oxide-added nonionic surfactant represented by the following formula: n is an integer of 10 to 50.

The compounds of the present invention can be obtained by known methods. That is, phosphoric acid esters and their salts include hexyl alcohol, heptyl alcohol, octyl alcohol, 2-ethylhexyl alcohol, decyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, octadecyl alcohol, and octadecyl alcohol. Higher alcohols such as alcohol, phenol, or alkylphenols such as nonylphenol, dodecylphenol, and dinonylphenol are esterified with phosphoric anhydride, or higher alcohols, phenols, and alkylphenols are converted to ethylene oxide and propylene oxide by known methods. It can be obtained by adding an alkylene oxide such as, and then esterifying it with phosphoric anhydride.

Next, the phosphoric acid ester is neutralized to an appropriate pH with sodium hydroxide, calcium hydroxide, magnesium hydroxide, monoethanolamine, jetanolamine, triethanolamine, monoisopropanolamine, trimethylamine, triethylamine, aqueous ammonia, etc. This makes it possible to obtain partially or completely neutralized phosphoric esters, but from the viewpoint of effectiveness and low foaming properties, sodium salts of phosphoric esters having 2-ethylhexanol or octatool as a hydrophobic group are particularly preferred.

The arylphenol alkylene oxide-added nonionic surfactant of the present invention can also be easily obtained by known methods. That is, alkylene oxide is added to arylphenols such as benzylated phenol, dibenzylated phenol, tribenzylated phenol, styrylphenol, distyrylphenol, tristyrylphenol, cumylphenol, dicumylphenol, etc. by a conventional method. The arylphenol is preferably cumylphenol from the viewpoint of dispersion effect and low air entrainment, and the alkylene oxide is ethylene oxide, propylene oxide, or a mixture thereof, but preferably ethylene oxide is used, and the number of moles added is preferably ethylene oxide. 8 to 25.1 In the cement dispersant of the present invention, when the phosphoric acid ester or its salt and the arylphenol alkylene oxide-added nonionic surfactant are used alone, they exhibit almost no dispersibility; It shows good dispersibility when mixed in a ratio of 90:10 to 10:90, especially when the mixing ratio is 60 to 4.
If the latter is used in an amount of 0 parts by weight and 40 to 60 parts by weight, a remarkable dispersion effect can be obtained.

[For production]

The cement dispersant of the present invention can be used in concrete and mortar using various cements such as Portland cement, fly ash cement, special cement, and mixed cement.

In the cement dispersant of the present invention, there is hardly any dispersion effect when each component is used alone, but due to the phase opening effect due to the combination of phosphoric acid ester or its salt and arylphenol alkylene oxide-added nonionic surfactant. , exhibiting excellent dispersibility. Also, one of the characteristics is that there is little air entrainment, but other nonionic surfactants or antifoaming agents may be added depending on the case.

Furthermore, the cement dispersant of the present invention can be used in combination or in combination with other generally known cement dispersants.

The amount of the dispersant for cement of the present invention used is generally 1
It is added in an amount of 0.2 to 0.5 parts by weight per 00 parts by weight, and the method of adding it is the same as that for cement dispersants, which is usually done by adding it as a undiluted solution during cement kneading, or
It is diluted in kneading water in advance and added. Alternatively, it may be added after mixing concrete or mortar and uniformly kneaded again. Further, the two components of the cement dispersant of the present invention may be added separately at predetermined ratios.

The cement dispersant according to the present invention will be explained below with reference to Examples, but the present invention is not limited thereto.

Examples 1 to 4 (Synthesis of phosphoric acid ester or salt thereof of the present invention) To 220 g (1 mol) of industrial nonylphenol was added 0.5 g of caustic potassium as a catalyst, and 264 g (6 mol) of ethylene oxide was added.
213 g (1.5 mol) of phosphoric anhydride was added at 50°C and reacted at 100°C for 3 hours.
It was partially neutralized with alkaline water in which 40 g of sodium hydroxide was dissolved in 60 g to obtain 2,397 g of a sodium phosphate ester salt of the present invention having a water content of 70.2% and a pH of 5.1 (hereinafter referred to as A-1).

(Synthesis of arylphenol alkylene oxide-added nonionic surfactant of the present invention) 406 g (1 mol) of tristyrylphenol and 1.2 g of caustic potassium as a catalyst.
was added, and 660 g (15 mol) of ethylene oxide was reacted in an autoclave at 170 to 180°C for 3 hours to obtain 1066 g of the arylphenol alkylene oxide-added nonionic surfactant of the present invention. (Hereafter B
-1).

(Manufacture of Blend Nos. 1 to 6) A-1 and B-1 were blended in the pure weight ratio as shown in Table 1 to obtain samples of Blend Nos. 1 to 6.

Table 1 Production of Mixtures 1 to 6 In order to clarify the performance of the samples from Mixtures 1 to 6 as dispersants for cement, JIS R-5201 was used.
A mortar flow test was conducted according to the method of . The test results are shown in Table 2.

Note that the plain mortar was blended in the following weight ratio.

Ordinary Portland cement 1 part Toyoura standard sand
2 water 0.
5 In addition, the dispersant is 0°4 relative to cement in terms of pure content.
A mortar was prepared by previously dissolving a weight % amount in kneading water.

Table 2 Examples 1-4 and Comparative Examples 1-2 Examples 5-2
(Synthesis of phosphoric esters and salts thereof of the present invention) Phosphoric esters and salts thereof A-2 to A-11 were synthesized as shown in Table 3 in the same manner as A-1. This product was used for the formulation described later.

(Synthesis of arylphenol alkylene oxide-added nonionic surfactant of the present invention) Similar to B-1, arylphenol alkylene oxide adducts, B-2 to B
-10 was synthesized as shown in Table 4, and the product was used for the formulation described later.

(Preparation of compounds 7 to 22 for blending) Compounds A-2 to A-11 and B-2 to B-1o were blended in the pure weight ratio as shown in Table 5, and samples of blended compounds 7 to 22 were mixed. Obtained.

This sample will be used for the test described below.

Table 5 Production of formulations 7-24 Mortar flow tests were conducted on samples of formulations 7-22 in the same manner as in Examples 1-4. The results are shown in Table 6.

Examples 21 to 26 and Comparative Example 4 A mortar test was conducted on the cement dispersant of the present invention. The mortar formulation was the same as in Examples 1 to 4, and the amount of dispersant added was adjusted so that the mortar flow value per mortar was approximately 170. Flow value and compressive strength are JIS R-520
The test method in 1 was followed.

The test results are shown in Table 7.

〔Effect of the invention〕

It is clear from Tables 2 and 6 that the dispersant of the present invention brings about a remarkable phase opening effect when blended, and Table 7 shows that the dispersant of the present invention has a significantly lower phase opening effect than known dispersants. It can be seen that a large dispersion effect can be obtained with a small amount of addition, and that it has the same or better performance in terms of compressive strength, and has no adverse effect on the strength of concrete.

Claims (1)

[Claims] General formula▲ Numerical formulas, chemical formulas, tables, etc.▼・・・・・・(1) [However, R_1 is a phenyl group, a straight chain or branched alkyl group having 6 to 18 carbon atoms, or an alkenyl group , or an alkylphenyl group having an alkyl group having 8 to 18 carbon atoms; AO represents an alkylene oxide group in which A is an ethyl group or an ethyl group and a propyl group; n is 0 to 30;
m represents an integer of 1 or 2, m+l represents an integer of 3, M is hydrogen, a monovalent or divalent metal salt, an ammonium salt, or an alkyl group having 3 or less carbon atoms or an N-alkyl group having an alkanol group (or alkanol) 90 to 10 parts by weight of at least one kind of phosphoric acid ester or its salt represented by [indicating ammonium salt] and the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (2) [However, R_2 is a benzyl group , styryl group, cumyl group, AO represents an ethyl group or an alkylene oxide group consisting of an ethyl group and a propyl group, m is 1 to 3, n
is an integer of 30 to 50] A dispersant composition for cement comprising 10 to 90 parts by weight of an arylphenol alkylene oxide-added nonionic surfactant.