JP2002102670A - Inorganic dispersant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inorganic dispersant which is excellent in bond force and free from the generation of an edge break and a crack. SOLUTION: The inorganic dispersant is incorporated with a terpene-maleic anhydride copolymer and/or its derivative.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terpene-maleic anhydride copolymer and / or a derivative thereof as an inorganic dispersant having excellent dispersibility and bonding strength of refractory particles.

[0002]

2. Description of the Related Art When dispersing inorganic pigments, fillers or ceramic powders such as clay, calcium carbonate, alumina and talc into a water-based slurry, they are added in a small amount to have low viscosity and excellent fluidity. It is used to make a dispersion. When adjusting the refractory, as those conventionally used as a binder between inorganic substances used as refractory particles, mineral plastics, sugar, asphalt,
Molasses, polyvinyl alcohol, lignin sulfonate, methylcellulose, carboxymethylcellulose,
Alginate and the like are used. As mineral plastics, there are bentonite, clay, refractory clay, and the like. These substances are not compatible with basic substances or other refractory substances at high temperatures and easily produce low melting point compounds.
When heated to a use temperature of 000 ° C. or higher, the bonding strength at high temperatures may decrease. Also, sugar, asphalt,
Refractories using molasses, polyvinyl alcohol, celluloses, ligninsulfonate, and the like are liable to cause corner breaks and cracks.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional drawbacks of refractory dispersants and to provide an inorganic dispersant which is excellent in bonding strength and does not cause corner collapse or cracking. And

[0004]

The present inventors have conducted various studies to solve the above-mentioned problems, and as a result, have found that a terpene-maleic anhydride copolymer and / or a derivative thereof is blended as a dispersant. The present inventors have found that an inorganic dispersing agent which is excellent in bonding strength and does not generate corner breaks or cracks can be obtained, and completed the present invention. That is, the present invention is characterized by using a terpene-maleic anhydride copolymer and / or a derivative thereof as an inorganic dispersant such as a refractory.

The terpene-maleic anhydride copolymer used in the inorganic dispersant of the present invention is produced by radical polymerization of a terpene compound and maleic anhydride. For radical polymerization of terpene compounds and maleic anhydride,
Eur. Polym. J. , 17,961-968,1
981 and Eur. Polym. J. , 24 (5), 45
3-456, 1988, Macromol. Chem.
Phys. , 195, 1848-1850, 1994 describe a production method and the like. Also, Table 9-51
No. 1012 discloses a solventless production method.
That is, it is manufactured by the following method. Using a terpene compound and maleic anhydride as raw material monomers, charging a solvent such as tetrahydrofuran or toluene into a flask, dropping an organic peroxide such as BPO (benzoyl peroxide) as a reaction initiator, and reacting for several hours to synthesize. Is done.
In that case, the obtained copolymer has a yield of 95 wt% or more and a molecular weight (Mw, GPC method) of 1,000 to 50,000.

Examples of the starting terpene compound include terpene hydrocarbons, terpene alcohols, terpene aldehydes and the like, and among them, cyclic terpene compounds such as limonene, dipentene, terpinolene, pinene, terpinene and mentadien are preferable.

In addition, imide compounds and esterified compounds which are derivatives of the terpene-maleic anhydride copolymer are preferably used.

Further, the terpene-maleic anhydride copolymer and / or a derivative thereof are insoluble in water but soluble in an aqueous alkali solution, so that caustic alkali, alkali carbonate,
It may be used by dissolving it in an aqueous solution containing an alkaline substance such as ammonia or organic amines.

The compounding amount of the terpene-maleic anhydride copolymer and / or a derivative thereof of the present invention is desirably 0.1 to 10% by weight based on the refractory particles. 0.
If it is less than 1 wt%, a sufficient bonding force cannot be obtained, and
If the amount exceeds wt%, the adhesive strength becomes too large or the content of organic substances increases, and the quality of the product deteriorates. Further, the terpene-maleic anhydride copolymer and / or its derivative can be used alone as a binder, but conventionally used lignin sulfonate, methyl cellulose, carboxymethyl cellulose, alginate, polyvinyl alcohol, Organic binders such as molasses and asphalt, clays such as bentonite and clay, and mineral plastics such as refractory clay can be used alone or in combination of two or more.

[0010] The refractory particles as referred to in the present invention are a general term for raw material particles for producing a nonmetallic material which is hardly melted even at a high temperature.
Naturally occurring minerals can be used as they are, or these raw materials can be used alone or in combination of two or more kinds and calcined, and then pulverized particles can be used. The components include minerals composed of oxides such as aluminum, silicon, magnesium, iron, chromium, and zircon, silicon carbide, and minerals composed of graphite.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, Synthesis Examples, Examples, and
The present invention will be described with reference to comparative examples, but the present invention is not limited to these without departing from the gist thereof. Synthesis Example 1 68 g of limonene, 98 g of maleic anhydride, and 166 g of tetrahydrofuran were charged into a flask equipped with a stirrer, a condenser, and a thermometer, and heated to 60 ° C. under a nitrogen stream. After the internal temperature is stabilized, BPO is added dropwise as an initiator over 1 hour. After completion of the dropwise addition, a post-reaction was carried out, and the copolymer was recovered by filtration, washed with hexane and dried to obtain a resin. The yield of the obtained copolymer was 97% by weight, and the average molecular weight (Mw) in terms of polystyrene was 150 by GPC (gel permeation chromatography).
00, acid value = 465.

Examples 1-4 A terpene-maleic anhydride copolymer was neutralized with aqueous ammonia to prepare an alkaline aqueous solution having a degree of neutralization of 50 wt% and a resin concentration of 20 wt%. A high-purity alumina raw material was used as the refractory particles, and the alkali aqueous solution was added thereto, and the amount of the resin added to the aggregate was 0.2, 0.5, 1.0, and 1.
It was adjusted so that the addition amount of 5 wt% and water was 5 wt%. After sufficient kneading, 100 g was pressed with a pressing pressure of 1000
Formed at kgf / cm ² for 5 minutes, 10mm × 10mm ×
A 120 mm prismatic compact was obtained. (Hereinafter, this molded body is referred to as a green molded body.) After molding, the molded body was dried at 200 ° C. for 2 hours, and then fired at 1600 ° C. The bending strength of these green compacts and sintered compacts is JIS-K-7203.
In accordance with Shimadzu AUTOGRAPH (AGS-D
Shape).

Comparative Example 1 The procedure of Example 1 was repeated except that the amount of the terpene-maleic anhydride copolymer used in Example 1 was changed to 0%.

Comparative Example 2 Example 3 was repeated except that a lignin sulfonate was used in place of the terpene-maleic anhydride copolymer used in Example 3.
And went exactly the same.

[0015]

[Table 1]

[0016]

According to the present invention, by blending a terpene-maleic anhydride copolymer and / or a derivative thereof as an inorganic dispersant, an inorganic dispersant excellent in bonding strength of refractory particles can be provided. .

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 4D077 AA03 AB02 AB03 AB20 AC05 BA02 BA07 DA02X DD67X DE04X DE06X 4J100 AK32P AR18Q AS15Q AU21Q BA03Q BA13Q CA04 DA01 JA15

Claims (2)

[Claims] An inorganic dispersant comprising a terpene-maleic anhydride copolymer and / or a derivative thereof. 2. The terpene-maleic anhydride copolymer has a molecular weight of 10 based on GPC (gel permeation chromatography) method and polystyrene equivalent average molecular weight (Mw).
The molar ratio of the terpene compound to maleic anhydride is 1: 0.5 to 3, and the molar ratio is 1: 0.5 to 3.
The inorganic dispersant according to any one of the preceding claims.