JPH09248438A - Dispersant for inorganic powder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the lowering of viscosity in a predetermined flowing state by adding a water-soluble cocondensate or watersoluble copolymer into which an oxypropylene group and/or a random polymerized chain of an oxypropylene group and an oxyethylene group is introduced as an essential component. SOLUTION: A water-soluble cocondensate or water-soluble copolymer into which an oxypropylene. group and/or a random polymerized chain (A) of an oxybutylene group and an oxyethylene group is introduced is contained as an essential component. When an oxypropylene group and/or a random polymerized chain (MO chain) of an oxybutylene group and an oxyethylene group is introduced into an AO chain, viscosity is reduced to a large extent as compared with such a case that a block polymerized chain of a polyethylene oxide, polypropylene oxide chain or a polybutylene oxide chain is introduced. In order to more stabilize the effect reducing viscosity, it is pref. that an addition mol number of an oxypropylene group and/or an oxybutylene group is 10% of an MO chain or more.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a dispersant for inorganic powder. More specifically, the present invention relates to a dispersant for the purpose of making a high-concentration slurry of pigments, clay, etc. and reducing the viscosity of hydraulic compositions such as gypsum, cement, mortar, and concrete.

[0002]

2. Description of the Related Art
Sodium polyacrylate (hereinafter referred to as polycarboxylic acid type) is known as a dispersant for pigments and clay minerals used for the purpose of improving fluidity and increasing slurry concentration.
Further, a naphthalenesulfonic acid formaldehyde condensate (hereinafter referred to as a naphthalene type) is used as a typical dispersant for gypsum and cement.

However, in recent years, hydraulic structures using gypsum and cement have been shifting to a direction of ultrahigh strength. The most effective and simple way to improve the strength of such a hydraulic structure is to reduce the water content of the system. However, it is difficult to increase the strength of the present dispersant by reducing the water content. That is, by reducing the water content, the fluidity is lowered and the viscosity is increased, which adversely affects pumping.

In recent years, the development of a polycarboxylic acid system exhibiting excellent dispersibility has made it possible to exhibit fluidity in a region where the water content is small. For example, a copolymer of a polyalkylene oxide monoester monomer having an unsaturated bond and an acrylic acid-based and / or unsaturated dicarboxylic acid-based monomer (Japanese Patent Publication No. 59-18338, Japanese Patent Publication No. 2-78978). Water-soluble vinyl polymers such as the above-mentioned publication). Furthermore, the present inventors have dramatically improved the fluidity by making the polyalkylene glycol chain a long chain (Japanese Patent Application No. 6-1010989). However, these dispersants are not sufficient for decreasing the viscosity, and improvement is desired.

[0005]

The inventors of the present invention have found from the knowledge obtained by the prior art that, in a dispersion system in a high particle concentration region where the ionic strength of the system is generally high, a steric barrier is generated rather than a dispersion mechanism by electrostatic repulsion. Considering that the dispersion mechanism is effective, paying attention to the polyalkylene oxide chain (hereinafter abbreviated as AO chain), which is a main component of the steric barrier, and investigating various relationships with fluidity and viscosity, the results show that It has been found that the addition monomer species of the chains and their addition forms are highly associated with viscosity reduction, and a dispersant that solves the above mentioned problems, namely a dispersion that can achieve viscosity reduction under a given fluidity. It came to complete the agent.

That is, the present invention contains a water-soluble cocondensate or a water-soluble copolymer having an oxypropylene group and / or a random polymer chain (A) of an oxybutylene group and an oxyethylene group as an essential component. The present invention relates to a dispersant for inorganic powder.

The present invention also provides a block polymer chain (B) in which a random polymer chain (a) of an oxypropylene group and / or an oxybutylene group and an oxyethylene group and a polyethylene oxide chain (b) are alternately bonded. The present invention relates to a dispersant for inorganic powder, which contains the introduced water-soluble copolymer or water-soluble cocondensate as an essential component.

In the present invention, when a random polymer chain of oxypropylene group and / or oxybutylene group and oxyethylene group (hereinafter abbreviated as MO chain) is introduced into the AO chain, polyethylene oxide chain, polypropylene oxide chain or It was found that the viscosity is significantly reduced as compared with the case where a block polymerized chain of polybutylene oxide chain (hereinafter, abbreviated as EO chain, PO chain and BO chain, respectively) is introduced.

In the prior art, the effect of introducing an AO chain has been confirmed by focusing only on the fluidity expression in the high particle concentration region, and a description on addition monomers of the AO chain, their addition forms and viscosity reduction. However, since the introduction of the MO chain is not described even in the examples of the prior art, the present invention has created a function (having both high fluidity and low viscosity) which has not been available in the past.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. In the present invention, the greatest effect of viscosity reduction is that all AO chains are MO chains. Also,
In order to make the effect of viscosity reduction more stable, the number of moles added of the oxypropylene group and / or oxybutylene group is
It is preferably 10% or more of the number of moles of the chain. However, when the oxypropylene group and / or oxybutylene group is too much, the hydrophobicity becomes strong and the dispersibility decreases, so the number of moles of the oxypropylene group and / or oxybutylene group added is 80% of the number of moles of the MO chain. It is necessary to be below, and more preferably 60% or below. Especially,
When the number of added moles of MO chain is less than 20 moles, the number of added moles of oxypropylene group and / or oxybutylene group is
If it exceeds 80%, the dispersibility will be significantly reduced.

Further, in order to enhance the dispersive power and impart fluidity, a block polymer chain in which EO chains are introduced and EO chains and MO chains are alternately bonded is preferable. In this case, it is more preferable to reduce the viscosity that the MO chain is located on the free end side. Since the synthesis time is long when the EO chains and the MO chains are alternately bonded, the following simple bonding pattern is preferable in view of the manufacturing cost. It has an effective dispersibility and a viscosity-reducing effect, and the most advantageous production cost is that the AO chain is composed of two chains, a MO chain on the free end side and an EO chain on the main chain side end. Further, when comparing propylene oxide and butylene oxide, butylene oxide has a larger effect of reducing viscosity, but considering production cost, it is preferable to use only cheaper propylene oxide.

Based on the effect of introducing the MO chain described above, the following more detailed functional design is possible. That is, in order to limit the function to dispersibility and decrease in viscosity and suppress the production cost, it is sufficient that the AO chains are all MO chains, and the number of moles constituting the AO chains is preferably 5 to 300 moles on average. In order to further enhance the dispersibility, an EO chain is introduced, the number of moles constituting the entire AO is 10 to 300 moles on average, and the MO in the AO chain is increased.
The number of moles of the chain is at least 5 or more, and MO
It is desirable that the number of added moles of the oxypropylene group and / or the oxybutylene group in the chain is at least 2 or more.

In order to impart the curing rate (low retardation of curing rate) of the hydraulic composition in addition to the reduction of dispersibility and viscosity, AO is used.
The average number of moles constituting the chain is preferably in the range of 50 to 300 moles.

To impart dispersibility, viscosity reduction and curing rate of the hydraulic composition, as well as maintaining dispersibility (small decrease in fluidity with time), the number of moles constituting the AO chain is 110 on average.
A range of ~ 300 mol is good.

In order to more stably express the function of the EO introduction system, it is desirable that the number of moles constituting the MO chain is 10 to 90%, and in order to achieve the best balance between dispersibility and viscosity reduction, M
Most preferably, the number of moles of O chain is 10 to 60%. To further stabilize the viscosity reducing effect, the number of added moles of oxypropylene group and / or oxybutylene group is
It is preferably 10 to 90% of the number of moles of MO chains. In order to maximize the balance between reduction of viscosity and other functions, it is desirable that the number of moles of oxypropylene group and / or oxybutylene group added is 10 to 60% of the number of moles of MO chain.

The main chain of the cocondensate or copolymer introduced with the above AO chain is not limited, and any water-soluble main chain can be used. Examples of the main chain of the cocondensate include those having an aromatic ring skeleton and, for example, a skeleton containing one or more selected from naphthalene, phenol, aniline, melamine, and urea. . In addition, one or two of a sulfonic acid group, a methylsulfonic acid group, a carboxyl group, or the like is contained in the main chain.
Those containing one or more adsorbing groups are mentioned. Further, water-soluble salts thereof, for example, metal salts or ammonium salts of sodium salt, potassium salt, calcium salt, magnesium salt, triethanolamine salt, diethanolamine salt, monoethanolamine salt and the like can be mentioned.

Specific structures include phenol,
An example is a co-condensate of a monomer obtained by adding alkylene oxide to aniline or the like and a phenol sulfonic acid, naphthalene sulfonic acid, hydroxybenzoic acid, a methyl sulfonate of melamine, or a methyl sulfonate of urea other than an aromatic ring. Can be mentioned.

These co-condensation reactions can be produced by known methods for producing water-soluble resins (see Polymer Chemistry, Kagaku Dojin, p.235-p.244).

Further, the main chain of the copolymer introduced with the above AO chain is not limited, and any water-soluble one can be used. The main chain of the copolymer, those containing a carboxyl group, a sulfonic acid group, an amide group, etc.,
Also, water-soluble salts thereof are used. Examples of the water-soluble salt include metal salts and ammonium salts of sodium salt, potassium salt, calcium salt, magnesium salt, triethanolamine salt, diethanolamine salt and monoethanolamine salt.

As an example of the copolymer, an ester of (meth) acrylic acid or maleic acid with methanol added with alkylene oxide (a), an acrylic acid type monomer or an unsaturated dicarboxylic acid (ro ) With a copolymer or water-soluble salt, or allyl alcohol, polyhydric alcohol, unsaturated dicarboxylic acid, dehydrogenated (oxidized) product of fatty acid with alkylene oxide (c) and acrylic acid-based monomer Examples thereof include a polymer, a copolymer with an unsaturated dicarboxylic acid (d), a water-soluble salt, and the like.

Examples of acrylic acid monomers and unsaturated dicarboxylic acids include acrylic acid, methacrylic acid, crotonic acid, maleic anhydride, itaconic anhydride, itaconic acid,
Examples thereof include citraconic anhydride, citraconic acid, fumaric acid and the like.

Examples of polyhydric alcohols include dihydric to hexahydric alcohols such as ethylene glycol, propylene glycol, glycerin, polyglycerin, trimethylolpropane, pentaerythritol and sorbitol.

Further, copolymers containing a sulfone group such as allylsulfonic acid and methallylsulfonic acid are also used.

These copolymers can be obtained by a known production method. For example, JP-A-59-162163 and JP-A-2-11
No. 542, JP2-78972, JP2-75677, JP
Examples include the polymerization methods described in 1-226757 and JP-A-58-38380.

The co-condensate or copolymer in the present invention has a composition ratio of a monomer containing an oxyalkylene group to a monomer to be co-condensed or copolymerized to a monomer containing an oxyalkylene group. Body / cocondensation or copolymerization monomer = 1 /
A range of 100 to 100/100 (molar ratio) is effective in reducing fluidity and viscosity, and 10/100 to 60/100 (molar ratio) is more excellent. If it is less than this range or exceeds this range, the dispersibility tends to decrease, which is not preferable.

The molecular weight of the cocondensate or copolymer in the present invention is in the range of 1,000 to 500,000 (gel permeation chromatography method / water system, converted to sodium polystyrenesulfonate), which is excellent in fluidity and viscosity reduction.
The range of 5,000 to 100,000 is even better. Molecular weight 1,000
If it is less than 500,000 or more than 500,000, the fluidity tends to decrease, which is not preferable.

When the dispersant of the present invention is added as an inorganic powder dispersant, the addition amount is 0.01 to 1.0 with respect to the inorganic powder.
Weight percent is preferred and 0.05 to 0.5 weight percent is more preferred.

The dispersant of the present invention can be used in combination with known additives (agents). For example, a dispersant, a foaming agent, a defoaming agent, a waterproofing agent, a preservative, a thickener, a hardening accelerator, a hardening retarder, fly ash, silica fume and the like can be mentioned.

The dispersant of the present invention is used for inorganic powders such as pigments, clay substances, sands, cements and gypsum, but it can also be used as a dispersant for organic pigments and coal. it can.

[0030]

EXAMPLES Hereinafter, the present invention will be described specifically, but the present invention is not limited to these examples. The method for producing the cocondensate and the copolymer used in the present invention is described in
5-231340, JP-A-59-162163, JP-A2-11542,
JP 2-78972 A, JP 2-75677 A, JP 1-226757 A
No. 58-38380, etc., and the molecular weights of the co-condensate and the copolymer used are those determined from the gel permeation chromatography method / water system and the molecular weight in terms of sodium polystyrene sulfonate. Is.

The contents and symbols of the dispersants used in the present invention are shown in Tables 1 and 2.

[0032]

[Table 1]

[0033]

[Table 2]

* 1: Block addition, * 2: Random addition, *
3: All butylene oxides The abbreviations in Tables 1 and 2 are as follows. Me (AO) MAAEst: Methanol (AO) methacrylate ester,
MAA: methacrylic acid, Ph: phenol, Alc: alcohol, AA: acrylic acid.

Further, the method for producing the AO chain containing the MO chain is as follows. A catalytic amount of an alkaline substance is added to the raw material alcohol, a predetermined amount of a mixture of ethylene oxide and propylene oxide mixed in advance is subjected to an addition polymerization reaction (A), and then a predetermined amount of ethylene oxide is subjected to an addition polymerization reaction (B). Let In the first addition polymerization reaction (A), random polymerization of ethylene oxide and propylene oxide is obtained, and in the second addition polymerization reaction (B), a block polymer chain of ethylene oxide is obtained.

The dispersants of the present invention and the comparative dispersants shown in Tables 1 and 2 were evaluated by the following methods. <Evaluation method-1> A dispersant was added to titanium dioxide (1000 parts) and water (215 parts) at a concentration of 0.2% based on titanium dioxide, and the mixture was stirred with a homomixer (manufactured by Tokushu Kika Co., Ltd.) at 12000 rpm for 90 seconds, and a B-type viscometer. The viscosity (centipoise) was measured with. Table 4 shows the results
And shown in Table 5.

<Evaluation method-2> The concrete was evaluated. Table 3 shows the mixing conditions of concrete.

[0038]

[Table 3]

For the production of concrete, the materials and the dispersant were prepared by a forced mixer according to the concrete composition shown in Table 3. Liquidity is a slump flow value (liquidity value) of 550 ±
The amount of dispersant added was adjusted to 50 mm. It was prepared with an antifoaming agent (silicone type) so that the air content was 2% or less. The slump flow value was measured according to JIS A-1101 method. The effect of decreasing the viscosity is (concrete spreading speed),
The time (seconds) until the slump cone was pulled up to reach 500 mm was measured and examined. The slump retention was evaluated by measuring the slump flow after 1 to 2 hours in a static state after preparing the concrete. The setting time was measured and evaluated according to ASTM-C-403. The results are shown in Tables 4 and 5.

[0040]

[Table 4]

[0041]

[Table 5]

The results of using the following dispersants as the dispersants other than the comparative products in Tables 4 and 5 are shown below.・ Comparative product regarding viscosity Na polyacrylate (trade name Poise 530, Kao Corporation)
2200cps ・ Comparative product for physical properties of concrete Naphthalene dispersant (trade name: Mighty 150, Kao Corporation)
(Manufactured); (Addition amount, spreading speed, slump flow (immediately after 1 hour, after 2 hours)) = (0.75%, 26.5 seconds, (530, 420, 370m
m)) <Evaluation Results / Effects> As is clear from Tables 4 and 5, the dispersant of the present invention is more excellent in the effect of decreasing the viscosity than the comparative product. Therefore, it is possible to increase the concentration of the pigment slurry system, solve the trouble of workability and workability of the cement composition, and easily obtain an ultra-high strength structure.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C09C 3/10 PCD C09C 3/10 PCD // C04B 103: 40 (72) Inventor Daisuke Shiba Wakayama Prefecture 1334 Minato Minato, Wakayama City Kao Co., Ltd. (72) Inventor Ya Fujikura Wakayama Prefecture 1334 Minato Wakayama City Minato Kao Co., Ltd. (72) Inventor Yoshinao Mitsuno Wakayama City Wakayama City Minato 1334 Kao Co., Ltd. Lab

Claims (19)

[Claims] 1. A random polymer chain (A) of an oxypropylene group and / or an oxybutylene group and an oxyethylene group.
A dispersant for inorganic powders, which comprises a water-soluble cocondensate or a water-soluble copolymer as an essential component. 2. The average number of introduced and added moles of the random polymer chain (A) is 5 to 300 moles.
The dispersant for inorganic powders described. 3. The inorganic powder according to claim 1, wherein the number of added moles of the oxypropylene group and / or the oxybutylene group is 10 to 90% of the number of moles of the random polymer chain (A). Body dispersant. 4. A random polymer chain (a) of an oxypropylene group and / or an oxybutylene group and an oxyethylene group.
A dispersant for inorganic powders containing a water-soluble copolymer or a water-soluble cocondensate as an essential component, in which a block polymer chain (B) in which a polyethylene oxide chain (b) is alternately bonded is introduced. 5. The dispersant for inorganic powder according to claim 4, wherein at least the free end side is a random polymer chain (a). 6. The dispersant for inorganic powder according to claim 5, which comprises a bond of two chains of a random polymer chain (a) on the free end side and a polyethylene oxide chain (b) on the main chain side end. 7. The number of introduced and added moles of the block polymer chain (B) is 10 to 300 moles on average, the number of moles of the random polymer chain (a) is at least 5 or more, and in the random polymer chain (a). 7. The dispersant for inorganic powder according to any one of claims 4 to 6, wherein the number of added moles of the oxypropylene group and / or the oxybutylene group is at least 2 or more. 8. The method according to claim 1, wherein the number of introduced and added moles of the random polymer chain (A) or the block polymer chain (B) is 50 to 300 moles on average. Dispersant for inorganic powder. 9. The dispersant for inorganic powder according to claim 8, wherein the number of introduced and added moles of the random polymer chain (A) or the block polymer chain (B) is 110 to 300 moles on average. 10. The composition according to claim 4, wherein the number of moles of the random polymer chain (a) is 10 to 90% of the number of moles of the block polymer chain (B). Dispersant for inorganic powder. 11. The dispersant for inorganic powder according to claim 10, wherein the number of moles of the random polymer chain (a) is 10 to 60% of the number of moles of the block polymer chain (B). 12. The addition mole number of the oxypropylene group and / or the oxybutylene group is 10 to 90% of the mole number of the random polymer chain (a), which is characterized in that.
The dispersant for inorganic powders described. 13. The inorganic powder for inorganic powder according to claim 12, wherein the number of moles of the oxypropylene group and / or oxybutylene group added is 10 to 60% of the number of moles of the random polymer chain (a). Dispersant. 14. The dispersant for inorganic powder according to claim 1, wherein the cocondensate has an aromatic ring skeleton. 15. The cocondensate is naphthalene, phenol,
The dispersant for inorganic powder according to any one of claims 1 to 14, which is composed of a skeleton having one kind or two or more kinds selected from aniline, melamine and urea. 16. The cocondensate contains one or more selected from a sulfonic acid group, a methylsulfonic acid group, a carboxyl group, and a water-soluble salt thereof, wherein the cocondensate contains one or more kinds. The dispersant for inorganic powder according to any one of 1. 17. The copolymer according to claim 1, wherein the copolymer contains one or more selected from a carboxyl group, a sulfonic acid group, an amide group and water-soluble salts thereof. The dispersant for inorganic powder according to Item 1. 18. A composition ratio of a monomer to be co-condensed or copolymerized to a monomer containing an oxyalkylene group is such that a monomer containing an oxyalkylene group / co-condensed or copolymerized monomer = The dispersant for inorganic powder according to any one of claims 1 to 17, wherein the dispersant is 1/100 to 100/100 (molar ratio). 19. The molecular weight of the cocondensate or copolymer is
The dispersant for inorganic powder according to any one of claims 1 to 18, wherein the dispersant is 1,000 to 500,000 (gel permeation chromatography method / water system, converted into sodium polystyrene sulfonate).