JP2696303B2 - Dispersant and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an industrial dispersant. More particularly, the present invention relates to a water reducing agent for cement, a dispersant for gypsum, a dye, inorganic and organic pigments, a slurry of fine coal powder, and the like.

[0002]

BACKGROUND OF THE INVENTION Conventionally, dispersants have been used for cement, gypsum, dyes, inorganic and organic pigments,
It is widely used in a wide range of fields such as coal fine powder slurry.
For example, cement compositions used in large quantities in civil engineering, construction, etc. include cement for the purpose of improving workability at the time of execution, and improving physical properties such as strength and durability of cured cement or prevention of cracking. Water reducing agent is used. Gypsum is widely used in the fields of building materials such as gypsum board and gypsum plaster, and shapes such as ceramics and castings. Conventionally, in a gypsum board or the like, a dispersant has been used to reduce the amount of mixed water to reduce the drying energy in the gypsum curing drying step, and reduce the stirring and mixing time and the drying time to improve productivity. .

As a dispersant in these fields, a dispersant containing a formaldehyde condensate of bisphenols and aminobenzenesulfonic acid as a main component has been proposed (JP-A-3-187960). However, when used as a water reducing agent for cement, the drawback that the fluidity of the cement composition is lost in a short time (slump loss) and the workability deteriorates has not been overcome yet. Further, when used as a gypsum dispersant, further reduction in the amount of water is required from the viewpoint of improvement in productivity, and further excellent dispersibility is required even if the stirring and mixing time is short.

[0004]

Accordingly, the present inventors have intensively studied a dispersant exhibiting better dispersibility than existing dispersants. As a result, by introducing amino acids into the molecules of the formaldehyde condensate of bisphenols and aromatic aminosulfonic acid, bisphenols, aromatic aminosulfonic acid and formaldehyde condensate show a dispersing effect that could not be expected. I found it. In particular, the following components A, B, and C are represented by A: B: C = 1.0: 0.6-0.
A condensate produced at a reaction molar ratio of 9: 0.05 to 0.3 is used as a dispersant for gypsum, and a condensate produced at a reaction molar ratio of A: B: C = 1.0: 1.0 to 2.0: 0.2 to 1.5 is used as a dispersant for cement. Were found to be suitable, respectively, and reached the present invention. A component: a bisphenol represented by the general formula (I),

[0005]

Embedded image

Component B: aminobenzenesulfonic acid Component C: amino acid

Specific examples of the bisphenols used in the present invention include 4,4'-dihydroxydiphenylmethane, 2,2-bis (4-hydroxyphenyl) propane, 4,4'-dihydroxydiphenylsulfone,
4-bis (4-hydroxyphenyl) valeric acid, 4,4-
Bis (4-hydroxyphenyl) butyric acid and isomers thereof are exemplified. These may be used in combination of two or more. Examples of the aminobenzenesulfonic acid include 4-aminobenzenesulfonic acid and its isomer, and 2-amino-sulfonic acid.
Those having a methyl group such as 5-methylbenzenesulfonic acid and isomers thereof can also be used.

As amino acids, glutamic acid, glycine, alanine, iminodiacetic acid, aspartic acid, serine, aminobutyric acid, glutathione, 6-aminohexanoic acid, valine, methionine, leucine and the like can be used. And iminodiacetic acid are preferred. As the formaldehyde used in the present invention, an aqueous formaldehyde solution (formalin) is usually used, but a formaldehyde derivative such as paraformaldehyde may be used. In addition, it is desirable that the total mole number of aminobenzenesulfonic acid and amino acid to 1 mole of bisphenol is 0.65 to 3.5. Formaldehydes are 1.2 to bisphenols.
It is preferred to use up to 5.0 moles.

In the production method of the present invention, it is necessary to add an alkali during the reaction. As the alkali to be used, sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, ammonium hydroxide and the like can be used, and it is desirable to add 0.6 to 4.0 mol to the bisphenols. If the total number of moles of aminobenzenesulfonic acid and amino acid per 1 mole of the above bisphenols is out of the range of moles of formaldehyde and alkali, the molecular weight is not included in the preferred range as a dispersant. The weight average molecular weight of the condensate is desirably in the range of 3,000 to 50,000. Particularly desirable is 7000 to 30,000, and if it is out of the range, the dispersibility and dispersion stability decrease. The weight average molecular weight can be easily measured by gel permeation chromatography (GPC).

The dispersant of the present invention can be obtained by reacting each of the above components at the above ratio under aqueous conditions at normal pressure or under pressure at a temperature of 30 to 140 ° C. for 2 to 60 hours. The condensate of the present invention can also be obtained by charging one of aminobenzenesulfonic acid and an amino acid simultaneously with a bisphenol to formaldehyde condensate, and then subjecting the other to formaldehyde condensation. The solids content of the dispersant of the present invention is 0.05% for gypsum or cement.
It is desirably about 1.0% by weight. If it is less than 0.05% by weight, the dispersibility is insufficient, and if it is more than 1.0% by weight, the gypsum or cement composition may cause a significant retardation of setting.

[0011]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.
In addition, "part" showing a compounding amount shows a weight part.

Synthesis Example 1 The following substances were charged in predetermined amounts into a reaction vessel equipped with a stirring device, a reflux device, a thermometer, and a formaldehyde dropping device. (1) 2,2-bis (4-hydroxyphenyl) propane 228.3 parts (1.0 mol) (2) 4-aminobenzenesulfonic acid 129.9 parts (0.75 mol) (3) Glutamic acid 22.1 parts (0.15 mol) (4) Water Sodium oxide 39.2 parts (0.98 mol) (5) Water 876.4 parts 37% formaldehyde aqueous solution 2
02.7 parts (2.5 mol of formaldehyde) was added dropwise over 1 hour, and the mixture was further reacted at that temperature for 20 hours to obtain an aqueous solution of the condensate of the present invention.

Synthesis Example 2 The following substances were charged in predetermined amounts into a reaction vessel equipped with a stirrer, a reflux device, a thermometer, and a formaldehyde dropping device. (1) 2,2-bis (4-hydroxyphenyl) propane 228.3 parts (1.0 mol) (2) 3-aminobenzenesulfonic acid 155.9 parts (0.9 mol) (3) Sodium hydroxide 40.0 parts (1.0 mol) (4 861.2 parts of water This solid-liquid was added at 37 ° C to a 37%
0.8 part (2.6 mol) was added dropwise over 1 hour,
Allowed to react for hours. After adding 44.1 parts (0.3 mol) of glutamic acid and 12.0 parts (0.3 mol) of sodium hydroxide to the reaction solution after the reaction, 24.3 parts (0.3 mol) of an aqueous formaldehyde solution was added to 3 parts.
Dropped in 0 minutes. This reaction solution was reacted at 90 ° C. for 5 hours to obtain an aqueous solution of a condensate.

Synthesis Examples 3 to 12 Synthesis Example 1 was repeated except that the components A, B, and C of the present invention were replaced with the compounds shown in Tables 1 and 2, respectively, and the molar ratio was changed as shown in Table 3. An aqueous solution of each condensate was obtained in exactly the same manner. The molar ratios of Synthesis Examples 1 to 5 are included in a molar ratio suitable for a gypsum dispersant, and Synthesis Examples 6 to 9 are included in a molar ratio suitable for a water reducing agent for cement.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

[Table 3]

The weight average molecular weights of the condensates obtained by the methods of Synthesis Examples 1 to 12 are shown in Table 4.

[0019]

[Table 4]

Synthesis Example 13 The following substances were charged into a reaction vessel in accordance with Example 1 described in JP-A-3-187960. (1) 2,2-bis (4-hydroxyphenyl) propane 114.2 parts (0.5 mol) (2) 4-aminobenzenesulfonic acid 173.2 parts (1.0 mol) (3) Sodium hydroxide 40.0 parts (1.0 mol) (4 ) Water 768.7 parts To this solid-liquid suspension, 162.2 parts (2 mol) of a 37% by weight aqueous formaldehyde solution was added dropwise at 90 ° C over 1 hour, and further reacted at the same temperature for 10 hours to obtain an aqueous solution of a condensate. Was.

Synthesis Example 14 The following substances were charged in predetermined amounts into a reaction vessel equipped with a stirring device, a reflux device, a thermometer, and a formaldehyde dropping device. (1) 2,2-bis (4-hydroxyphenyl) propane 274.0 parts (1.2 mol) (2) 4-aminobenzenesulfonic acid 173.2 parts (1.0 mol) (3) Sodium hydroxide 44.0 parts (1.1 mol) (4 ) Water 1575.0 parts To this solid-liquid suspension, 210.8 parts (2.6 mol) of a 37% by weight aqueous formaldehyde solution were added dropwise at a temperature of 60 ° C over 1 hour. Further reaction was carried out at that temperature for 35 hours to obtain an aqueous solution of a condensate.

Synthesis Example 15 According to JP-A-4-331751, predetermined amounts of the following substances were charged into a reaction vessel equipped with a stirrer, a reflux device, a thermometer, and a formaldehyde dropping device. (1) 4,4'-dihydroxydiphenylmethane 200.3 parts (1.0 mol) (2) Glutamic acid 147.1 parts (1.0 mol) (3) Sodium hydroxide 80.0 parts (2.0 mol) (4) Water 913.0 parts This solid-liquid suspension Then, 202.5 parts (2.5 mol) of a 37% by weight aqueous solution of formaldehyde were added dropwise at 80 ° C. over 1 hour, and the mixture was further reacted at that temperature for 5 hours to obtain an aqueous solution of a condensate.

Gypsum test 1100 parts of gypsum (trade name: SK manufactured by Mutsumi Chemical Industry Co., Ltd.) and 620 parts of water were stirred for 15 seconds with a mixer, and the inner diameter was 50 mm and the height was 50 m.
m into a hollow cylindrical container. After the container was pulled out upward, the diameter (flow value) of the circular spread of the gypsum slurry was measured at two places and averaged to be 100 mm. Next, as a dispersant, 2.2 parts (0.2% by weight based on gypsum) of the aqueous solution of the condensate of Synthesis Example 1 was added, and a flow value of 100 mm was obtained in the same manner as above except that the amount of water was changed with the same amount of gypsum. The amount of water indicated was 475 parts. Than this,
The water loss when adding 2.2 parts of the aqueous solution of the condensate of Synthesis Example 1 in terms of solid content was 13.2% from the following formula.

[0024]

The setting time of the gypsum was measured according to JIS R 9112, and the time when the gypsum cured product reached the maximum temperature was defined as the curing time. For Synthesis Examples 2 to 5, 10 to 12, the water reduction rate and the curing time were determined in the same manner. As a comparative example, the water reduction rate and the curing time were obtained in the same manner using Synthetic Example 14 and naphthalenesulfonic acid formaldehyde condensate (manufactured by Kao Corporation, trade name: Mighty 150, hereinafter abbreviated as NSF) which is a general-purpose dispersant. I asked. Table 5 shows the measurement results.

[0026]

[Table 5]

Concrete Test The slump loss (fluctuation in fluidity with time) of concrete to which the dispersant of the present invention was added was evaluated by using Synthesis Examples 6 to 12 as Synthesis Examples 13 and
15 and NSF. Table 6 shows the composition of the concrete. For the concrete, water containing cement, aggregate, and a water reducing agent was kneaded with a 100-liter portable tilting mixer for 3 minutes, and immediately after, 60 and 120 minutes later, the slump and the amount of air were measured. Concrete slump and air volume are JI
Performed according to SA 6204.

[0028]

[Table 6] 1) C cement: ordinary Portland cement W water: tap water S fine aggregate: river sand from Shimane specific gravity 2.59 coarse grain ratio 2.60 G coarse aggregate: crushed stone from Yamaguchi specific gravity 2.71 coarse grain ratio 6.86

Table 7 shows the measurement results.

[0030]

[Table 7] 1) Addition rate of solid content (to weight of cement) 2) Immediately after the amount of air is commercially available surfactant Sunflow AE-
Adjusted at 4.

The dispersant of the present invention has a greater water reduction rate in the gypsum test than the condensate of the comparative example, and a similar amount of slump can be obtained with a small amount of addition in the concrete test. This indicates that the dispersant of the present invention is excellent in dispersibility. Further, the change with time of the slump shows that the dispersant (water reducing agent) of the present invention has very little change with time in fluidity. The results of the setting test of gypsum show that the apparent curing time is almost the same as that of the conventional dispersant. From these results, it is clear that the dispersant of the present invention has excellent results.

[0032]

The dispersant of the present invention has excellent dispersibility and dispersion stability as compared with conventional dispersants, so that it can be used not only for water reducing agents for cement and dispersants for gypsum but also for dyes. It has excellent performance as a dispersant for inorganic and organic pigments, for coal fine powder slurries, and the like.

Continuation of the front page (72) Inventor Fumifumi Nakamoto 2-8-1 Iida-cho, Iwakuni-shi, Yamaguchi Prefecture Nippon Paper Industries Co., Ltd. Production Technology Laboratory (56) References JP-A-3-187960 (JP, A) JP-A-3-187960 Hei 4-331751 (JP, A)

Claims (6)

(57) [Claims] 1. A dispersant comprising a bisphenol, an aminobenzenesulfonic acid, and a formaldehyde condensate of an amino acid. 2. Under aqueous conditions, the following components A, B and C
A gypsum dispersant comprising a product obtained by subjecting components to formaldehyde condensation at a molar ratio of A: B: C = 1.0: 0.6 to 0.9: 0.05 to 0.3; A component: general formula (I) Bisphenols represented by the following: Component B: aminobenzenesulfonic acid Component C: amino acid 3. The composition according to claim 2, wherein A: B: C = 1.0: 1.0 to 2.0: 0.2 under aqueous conditions.
A water reducing agent for cement, comprising as a dispersant a product obtained by formaldehyde condensation at a molar ratio of up to 1.5. 4. Under an aqueous condition, the components A, B, and C according to claim 2 and an alkali and an aldehyde are combined with 1.
A production method in which a novel condensate is obtained by reacting at a molar ratio of 0: 0.6 to 2.0: 0.05 to 1.5: 0.6 to 4.0: 1.2 to 5.0. 5. The dispersant according to claim 2, wherein any one of glutamic acid, glycine, and iminodiacetic acid is used as the component C. 6. The method for producing a dispersant according to claim 4, wherein any one of glutamic acid, glycine, and iminodiacetic acid is used as the component C.