JPH1135792A - Binder composition for monolithic refractory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the use as a binder for hot repair materials such as a spraying material by blending a novolak phenol resin and a resol phenol resin at a specified ratio. SOLUTION: The blending ratio is (95:5) to (50:50). Raw materials of a phenol resin used comprise phenols, such as phenol and bisphenol A, and aldehydes usually comprising formalin. An inorganic acid or an organic acid such as p-toluenesulfonic acid is used as an acid catalyst in reacting a novolak phenol resin. A metal salt such as zinc acetate, an alkali or an amine is used as a catalyst in reacting a resol phenol resin. The novolak phenol resin used has a solution viscosity of at least 150 μm<2> /s. The composition is preferably in a powdery form, having a minimum value of torque (at 130 deg.C) of 5 kg.cm and a time for reaching a torque of 200 kg.cm of 3-12 min as determined by Brabender Plastograph.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a binder composition for amorphous refractories, and more particularly to a resin binder composition which can be used as a binder for a hot repair material such as a spray material.

[0002]

2. Description of the Related Art In recent years, the amount of graphite-containing unfired bricks using a phenolic resin as a binder has increased in converters, electric furnaces, ladles and the like. Along with this, there are cases where irregular shaped refractories mainly used for repairing furnace walls and furnace bottoms of the above steelmaking facilities also use aggregates such as graphite, magnesia and alumina mixed with phenolic resin as a binder. is increasing. Taking a baking material as an example, a binder in which a solid or powder phenol resin is used in combination with a wetting agent such as a polyhydric alcohol, or a novolak type phenol resin previously dissolved in a polyhydric alcohol is used as a binder.

On the other hand, a spraying material using a phenol resin as a binder has been studied. Generally, the spraying material is used as a repair material for a furnace wall such as a converter and a ladle. However, in the case of a hexamine-containing powdery novolak-type phenol resin, sufficient strength as a repair material cannot be obtained because of a large amount of volatile components at the time of curing. Also,
In the case of the powdered resol type phenol resin, the molecular weight is generally lower than that of the novolak type phenol resin, so that the powder resol type phenol resin is sagged from the wall surface before adhering and hardening on the wall surface, and thus has a disadvantage that sufficient repair performance cannot be obtained.

[0004]

SUMMARY OF THE INVENTION The inventor of the present invention has conducted intensive studies to overcome these drawbacks, and as a result, has found that the mixing ratio of novolak-type phenolic resin to resol-type phenolic resin is 95/5 to 50/50. Have been found to be applicable to irregular-shaped refractories such as sprayed materials, and have reached the present invention.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a binder composition for an amorphous refractory, wherein the compounding ratio of a novolak type phenol resin and a resol type phenol resin is 95/5 to 50/50. It is. Examples of phenols used as a raw material of the phenol resin used in the present invention include phenol, cresol xylenol, para-tert-butylphenol, para-octyl phenol, paranonyl phenol, para-cumyl phenol, and bisphenol A, and these may be used alone or in combination of two or more. Can be used. On the other hand, as aldehydes, formalin is usually used, but aldehyde-generating substances such as paraformaldehyde and trioxane, and benzaldehyde can also be used.

Examples of the acidic catalyst for reacting the novolak type phenol resin include inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid, or paratoluenesulfonic acid, benzenesulfonic acid, oxalic acid, maleic acid, formic acid, acetic acid, and amber. Organic acids such as acids can be used. Examples of the catalyst for reacting the resol-type phenol resin include metal salts such as zinc acetate, alkalis such as sodium hydroxide, potassium hydroxide, barium hydroxide, and calcium hydroxide, ammonia, and amines such as triethylamine. They can be used alone or in combination of two or more.

The compounding ratio of the novolak-type phenolic resin to the resol-type phenolic resin in the binder composition for an amorphous refractory used in the present invention is 95/5 to 50/50, preferably 90/10 to 60/40. If the ratio of the resole type phenolic resin is lower than this, it is difficult to obtain sufficient curability. On the other hand, if the ratio is higher than that of the resol-type phenol resin, the molecular weight of the whole resin becomes small, and the resin does not adhere well to the wall surface. Further, the volatile components at the time of curing the resin also increase, and sufficient strength cannot be obtained.

The shape of the binder composition for an amorphous refractory of the present invention is desirably a powder. In the case of a liquid, a volatile component at the time of construction increases, and it is difficult to obtain sufficient strength. In the case of a solid form, the dispersion in the aggregate used in combination becomes insufficient, and it is difficult to obtain a sufficient binder effect.

The solution viscosity of the novolak type phenolic resin of the binder composition for amorphous refractories used in the present invention is 150 μm.
m ² / s or more, preferably 180 μm ² / s or more. If the solution viscosity of the novolak type phenol resin is lower than this, sufficient hot adhesion cannot be obtained. Here, the solution viscosity is an index of the molecular weight of a phenol resin or the like. The higher the solution viscosity, the higher the molecular weight.
The measurement method is as follows:
1 and dissolved at 25 ° C. As a measuring instrument, Cannon Fenske was used.

The binder composition for an amorphous refractory used in the present invention has a temperature of 130 ° C. in a Brabender plastograph method.
The minimum value in the measurement torque at is preferably 5 kg ·
cm or more, more preferably 10 kg · cm or more. If the minimum value of the torque is lower than this, sufficient hot adhesion cannot be obtained. The Brabender plastograph method is a method of measuring a curing behavior of a molding material, a thermosetting resin, or the like until gelling, and shows a higher torque as the curing proceeds. In this study, a Labo Plastomill manufactured by Toyo Seiki Seisaku-sho, Ltd. was used.

The binder composition for the amorphous refractory used in the present invention has a temperature of 130 ° C. in a Brabender plastograph method.
The time required to reach a torque of 200 kg · cm is 3 to 12 minutes, preferably 4 to 10 minutes. 200
If the time required to reach kg · cm is shorter than this, the curing proceeds before adhering to the wall surface during hot work, resulting in insufficient adhesion. On the other hand, if it is shorter than this, the molten state of the resin becomes longer and liquid is dripped from the wall surface, so that it does not adhere sufficiently.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments. However, the present invention is not limited by the examples. Further, “parts” and “%” described in the text all mean “parts by weight” and “% by weight”.

Production Example 1 100 parts of phenol, 71 parts of 37% formalin and 1 part of oxalic acid were placed in a reactor equipped with a stirrer, reflux condenser and thermometer.
And then reacted under reflux conditions for 3 hours. Dehydration under reduced pressure until the desired water content and free phenol amount,
After removing the phenol, it was taken out to obtain a solid novolak type phenol resin A. This resin has a solution viscosity of 200
μm ² / s, free phenol 3.0%.

Production Example 2 100 parts of phenol, 65 parts of 37% formalin and 1 part of oxalic acid were placed in a reactor equipped with a stirrer, a reflux condenser and a thermometer.
And then reacted under reflux conditions for 3 hours. Dehydration under reduced pressure until the desired water content and free phenol amount,
After removing the phenol, it was taken out to obtain a solid novolak type phenol resin B. This resin has a solution viscosity of 100
μm ² / s and free phenol 1.0%.

Production Example 3 A reactor equipped with a stirrer, reflux condenser and thermometer was charged with 100 parts of phenol, 151 parts of 37% formalin and 23 parts of 28% aqueous ammonia, and the temperature was gradually raised. Inner temperature 80
Reflux at 15 ° C. for 15 minutes. After cooling to an internal temperature of 50 ° C., the mixture was allowed to stand, and separated water was removed. Then, the solution was dehydrated under reduced pressure at 60 ° C. to obtain a solid resol type phenol resin C. This resin had a melting point of 65 ° C. and 5.0% of free phenol.

Example 1 70 parts of a solid novolak type phenolic resin A having a solution viscosity of 200 μm ² / s produced in Production Example 1 and 30 parts of a solid resol type phenolic resin C produced in Production Example 3 were mixed and pulverized. Inventive binder composition D for amorphous refractories
I got This resin had an average particle size of 40 μm and a melting point of 92 ° C.

Example 2 A mixture of 80 parts of the solid novolak type phenolic resin A having a solution viscosity of 200 μm ² / s produced in Production Example 1 and 20 parts of the solid resol type phenolic resin C produced in Production Example 3 was mixed and pulverized. Inventive binder composition E for powdery amorphous refractories
I got This resin had an average particle size of 40 μm and a melting point of 97 ° C.

Comparative Example 1 97 parts of the solid novolak type phenolic resin A having a solution viscosity of 200 μm ² / s produced in Production Example 1 and 3 parts of the solid resol type phenolic resin C produced in Production Example 3 were mixed and ground. A phenolic resin composition F was obtained. This resin had an average particle size of 40 μm and a melting point of 105 ° C.

Comparative Example 2 40 parts of the solid novolak type phenolic resin A having a solution viscosity of 200 μm ² / s produced in Production Example 1 and 60 parts of the solid resol type phenolic resin C produced in Production Example 3 were mixed and ground. A phenolic resin composition G was obtained. This resin had an average particle size of 40 μm and a melting point of 80 ° C.

Comparative Example 3 60 parts of the solid novolak type phenolic resin B having a solution viscosity of 100 μm ² / s produced in Production Example 2 and 40 parts of the solid resol type phenolic resin C produced in Production Example 3 were mixed and pulverized. A phenolic resin composition H was obtained. This resin had an average particle size of 40 μm and a melting point of 78 ° C.

Comparative Example 4 100 parts of a solid novolak phenolic resin A having a solution viscosity of 200 μm ² / s prepared in Production Example 1 and 5 parts of hexamethylenetetramine were mixed and pulverized to obtain a powdery novolak phenolic resin composition I. I got This resin had an average particle size of 40 μm and a melting point of 105 ° C.

<Measurement by Brabender Plastograph Method> 30 parts of the binder composition or phenolic resin composition for amorphous refractories produced in Examples 1 and 2 and Comparative Examples 1 to 4 were heated to 130 ° C. in advance. It was quickly put into the mixer of Labo Plast Mill manufactured by Toyo Seiki Seisaku-sho, Ltd., and the torque was measured. The rotation of the rotor was performed at 50 rpm. FIG. 1 shows the measurement results.

<Practical test> A 20 cm x 20 cm x 1 cm ceramic sheet was placed in an electric furnace at an internal temperature of 1000 ° C.
Leave for 5 minutes. Thereafter, the ceramic sheet was vertically stood, and the binder composition for unshaped refractory or the phenolic resin composition produced in Examples 1 and 2 and Comparative Examples 1 to 4 were sprayed with a nozzle gun, respectively, and the adhesion was observed. . Further, the strength of the construction body after spraying was measured.

The test results, the minimum value of the torque in the Brabender plastograph method performed earlier, and the torque 2
Table 1 shows the time required to reach 00 kg · cm.

[Table 1]

In the above results, the larger the adhesion, the more
The lower the volatility, the better the performance as a spraying material. As is clear from Table 1, in Comparative Example 1, sufficient curability was not obtained due to a small amount of the resol-type phenolic resin, and therefore, the resin did not adhere to the ceramic sheet.
In Comparative Example 2, since the compounding ratio of the resole was too large, the torque minimum value in the Brabender plastograph method was small, and sufficient adhesion did not occur. Also, because there are many volatile components,
The strength of the construction body was also weak. In Comparative Example 3, since the solution viscosity of the novolak type phenol resin was low, that is, the molecular weight was small, the minimum value of the torque was low and the novolak type phenol resin did not adhere to the ceramic sheet. In Comparative Example 4, a novolak-type phenol resin having a high solution viscosity and hexamethylenetetramine as a curing agent were used. Therefore, although the torque minimum value was relatively high and the adhesion was moderate, a large amount of ammonia gas due to hexamethylenetetramine was generated, and the strength of the construction body was extremely low. On the other hand, in Examples 1 and 2, the curing characteristics by the Brabender plastograph method were appropriate, the adhesion in a practical test was large, and the strength of the construction was large.

[0026]

By using the novolak type phenolic resin and the resol type phenolic resin in a ratio of 95/5 to 50/50, it becomes possible to use it as a binder for a hot repair material such as a spray material.

[Brief description of the drawings]

Fig. 1 Torque measurement result by Brabender plastograph method

Claims (4)

[Claims] 1. A binder composition for an amorphous refractory, wherein the compounding ratio of a novolak type phenol resin and a resol type phenol resin is from 95/5 to 50/50. 2. The binder composition for an amorphous refractory according to claim 1, wherein the solution viscosity of the novolak type phenol resin is 150 μm ² / s or more. 3. The method according to claim 1, wherein
The binder composition for an amorphous refractory according to claim 1, wherein a minimum value of the torque is 5 kg · cm or more at a torque measured at 30 ° C. 4. A method according to the Brabender plastograph method.
At a torque measured at 30 ° C., a torque of 200 kg
2. The binder composition for an amorphous refractory according to claim 1, wherein a time required to reach cm is 3 to 12 minutes. 3.