JPS61276735A - Peroxide composition for casting mold - Google Patents

Abstract

PURPOSE:To provide the reduction of a production cost, the improvement of safety, etc. by incorporating respectively specific weight % of ketone peroxide, water, dilution stabilizer and solubilizer into a titled compsn. CONSTITUTION:The following compsn. is used as the peroxide compsn. for an acid curable cold box method: The hydrous ketone peroxide compsn. is constituted, by weight %, of >=20 and 35% ketone peroxide, 5-40% water, 10-50% dilution stabilizer and 5-50% solubilizer. Such hydrous ketone peroxide compsn. is obtd. by oxidizing at least one kind of aliphat. ketone of 3-8C or alicyclic ketone 6-10C with hydrogen peroxide water under acid catalyst then solubilizing the same with the dilution stabilizer and solubilizer. Since the compsn. is hydrous and does not require an intricate process for production, the reduction of the production cost and the improvement of the safety are made possible.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used when forming a long mold by adding sulfur dioxide to a monolithic refractory aggregate mixture containing an acid-curable resin and an oxidizing agent. It concerns oxidizing agents. More specifically,
The present invention relates to certain aqueous organic peroxide compositions used as oxidizing agents for nucleic acid curable templates.

[Conventional technology]

Conventionally, for high-speed mold production applications such as automobile castings, the cloning method, which uses novolac-type phenolic resin as a binder and heat-cures it, or the hot-box method, which heats and cures liquid phenolic resin or furan-based resin, has been widely used. has been used. All of these are 200-30
It is common practice to bake and harden at 0°C, which causes various problems such as energy consumption, hardening time, distortion of the mold, poor dimensions of the casting due to deformation, and working environment.

In recent years, the so-called cold box method, in which a mold is formed by blowing a gaseous or aerosol-like substance at room temperature, has been attracting attention 1 and becoming popular as a molding method to improve these difficulties.

As a cold box method, there is a urethane-based cold box method in which curing is performed using a polyol compound and a polyisocyanate as a binder and a tertiary amine as a catalyst. However, in the urethane cold box method, even if the granular refractory mixture containing polyol and polyisocyanate is left to stand, the curing reaction proceeds gradually, resulting in a short pot life of the mixture or problems such as drop defects, gas defects, etc. There are drawbacks such as many casting defects. Another cold box method currently available is an acid curing cold box method in which an acid curing resin and an oxidizing agent are added to granular refractories, and then sulfur dioxide is blown into the refractory to form a mold.

[Problem that the invention seeks to solve]

In this method, the curing reaction does not proceed unless the granular refractory mixture and sulfur dioxide come into contact with each other, so the pot life of the mixture is long, and acid-curing resins with excellent heat resistance, such as furan-based resins, are used as the binder. However, this acid-curing cold box method requires the use of an expensive organic peroxide as an oxidizing agent, and there are also concerns regarding the stability of the organic peroxide. Because of the drawback of insecurity, there is a demand for inexpensive and highly safe peroxides.

Hydrogen peroxide is an inexpensive and highly safe peroxide, but hydrogen peroxide easily decomposes due to alkaline earth metal oxides and other impurities contained in the granular refractory aggregate. The usable time after mixing a mixture of fire-resistant aggregate with resin and peroxide, the so-called pot life, is so short that it is practically unusable.

[Means for solving problems]

Under such circumstances, the inventors of the present invention have conducted extensive research and have come up with the invention of a peroxide composition for curable molds that is inexpensive, highly safe, and has excellent performance.

That is, the present invention provides a peroxide composition that is used as an oxidizing agent when producing a mold by injecting gaseous or aerosolized sulfur dioxide into a granular refractory aggregate mixture to which an acid-curable resin and an oxidizing agent have been added. A water-containing ketone peroxide composition containing a dilution stabilizer that has been solubilized with a solubilizer and prepared homogeneously, and in which the proportion of each component is 20% by weight or more of ketone peroxide35 Less than % by weight water 5-40% by weight dilution stabilizer 10-50% by weight solubilizer
The present invention relates to a peroxide composition for molds, characterized in that the content thereof is 5 to 50% by weight.

Usually, a ketone peroxide composition is prepared by dropwise reacting an aliphatic or alicyclic ketone with a hydrogen peroxide solution using a mineral acid such as sulfuric acid as a catalyst, and an aliphatic or aromatic dibasic acid diester as a carrier agent under cooling. After the completion of the process, the aqueous layer is separated, and the non-aqueous layer is neutralized, washed, dried, and purified to produce a non-aqueous peroxide composition. The manufacturing process for this product is complicated and requires a lot of man-hours, the yield is significantly lower considering the amount of raw materials used, and it is not only expensive, but also dangerous because it is non-aqueous.

On the other hand, polyhydric alcohols such as glycerin, N-methyl-2-
There are hydrous homogenized ketone peroxide compositions that use nitrogen-containing water-soluble solvents such as pyrrolidone as carrier agents, but these carrier agents act as curing retarders for acid-curing resins and are inexpensive and highly safe. When used as an oxidizing agent in the acid-curing cold box method, it causes poor curing of the mold, making it practically unusable.

The peroxide composition of the present invention improves these drawbacks, does not contain a solvent that acts as a curing retarder for homogenization, contains a dilution stabilizer, and is water-containing, so it can be used in the acid-curing cold box method. It has excellent performance as an oxidizing agent, does not require complicated manufacturing processes, is inexpensive, and has excellent fire safety due to its water content, providing practically satisfactory results. It is.

A preferred method for producing the hydrous ketone peroxide composition of the present invention is to add at least one type of aliphatic ketone having 3 to 8 carbon atoms or alicyclic ketone having 6 to 10 carbon atoms to water peroxide under an acid catalyst. This is a method of solubilizing ketone peroxide produced by oxidation with hydrogen water and a dilution stabilizer using a solubilizer without separating water during or after production.

The solubilizer used in the present invention includes water-soluble monocarboxylic acids, water-soluble hydroxy mono- or polycarboxylic acids, acidic alkali metal salts of polycarboxylic acids or hydroxy-polycarboxylic acids, water-soluble monoalcohol compounds, At least one selected from the group of water-soluble lactone compounds, water-soluble ketone compounds, water-soluble ether compounds, water-soluble ester compounds, and water-soluble ether ester compounds can be mentioned. Hydroxy polycarboxylic acid has 2 to 6 carbon atoms, polycarboxylic acid or acidic alkali metal salt of hydroxy polycarboxylic acid has 2 to 6 carbon atoms, and water-soluble monoalcohol has 1 to 6 carbon atoms. Inside is preferable.

The dilution stabilizers used in the present invention include the following (I) -
One or more compounds represented by (V) may be used.

X(-C-0-R1).

(In the formula, n is 1 to 3, and when n=1, X is an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, or aralkyl group having 1 to 20 carbon atoms.

In the case of n.2, X is an alkylene group having 2 to 20 carbon atoms, an alkenylene group,
Alkynylene group, cycloalkylene group, phenylene group,
It is an aralkylene group or an alkyl substituted product thereof.

When n=3, CCH3 For n=1 to 3, R1 may be the same or different, and the total number of carbon atoms in R3 is an alkyl group, alkenyl group, alkynyl group, or cycloalkyl group where n=60. , an aryl group, an aralkyl group, or a halogen, alkoxy, acyloxy, or alkoxycarbonyl substituted product thereof. ) (If) 0 R, -C-0(-Y-0-), Rff (in the formula, m is 1 to
It is an integer of 300.

Y is an alkylene group having 2 to 20 carbon atoms, an alkenylene group,
It is an alkynylene group, a phenylene group or an aralkylene group.

R1 and R may be the same or different, and are an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, or an aralkyl group having a total number of carbon atoms of 1 to 20.

R3 further includes a hydrogen atom and an acyl group. )(I[[) Glycerin esters CHt-0-C-R.

(In the formula, R,,R,,R are a hydrogen atom, or an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, or aralkyl group having a total number of carbon atoms of 1 to 60.

However, at least one of R4+R8+R6 is not a hydrogen atom. ) (IV) Phosphorus esters (in the formula, R7, R11, R9 are hydrogen atoms, or have 1 to 1 carbon atoms)
20 alkyl groups, alkenyl groups, alkynyl groups, aryol groups, aralkyl groups, or halogen-, alkoxy-, or acyloxy-substituted products thereof. However, R7, Ra
, Rv is not a hydrogen atom. )(
V) Saturated or unsaturated fatty acids having 12 to 24 carbon atoms, furfuryl alcohol, phenolic compounds, aliphatic or aromatic aldehyde compounds, furfuryl alcohol/formalin polycondensates, phenolic compounds/formalin polycondensates, urea/ Formalin polycondensate, melamine/formalin condensate.

The proportions of each component in the peroxide composition of the present invention are: ketone peroxide, 20% by weight or more and less than 35% by weight, water;
5-40% by weight dilution stabilizer
10-50% by weight solubilizer 5-
It is 50% by weight.

Furthermore, the composition of the present invention may contain a nonionic or anionic surfactant in addition to the above-mentioned essential components.

Generally, when forming a mold, silica sand containing quartz as a main component, zircon sand, and chromite sand are used as granular refractory aggregate, but this does not particularly limit the present invention. Examples of acid-curable resins include furan resins, phenol resins, urea resins, melamine resins, and co-condensates or mixtures thereof, and these resins are usually used in an amount of 5 to 20 parts by weight per 1000 parts by weight of the granular fire-resistant aggregate. part is used. The peroxide composition of the present invention usually has an aggregate of 1000
It is used in an amount of 3 to 10 parts by weight.

〔Example〕

Examples will be described below to explain the present invention in more detail, but the scope of the present invention is not limited by these Examples.

Examples 1 to 6 and Comparative Examples 1 to 3 3000 parts by weight of furan recycled sand, 24 parts by weight of furan resin,
A mixture obtained by adding and kneading 15 parts by weight of a peroxide composition was added to 25 parts by weight.
A mold of x 25 x 250 m/m was filled, gaseous sulfur dioxide was blown into the mold, and the mixture was washed with compressed air to form a mold. After molding, the bending strength of the mold was measured to examine its practical performance. At the same time, after the added kneaded mixture was left to stand for 1 hour, a mold was molded in the same manner, and the pot life of the mixture was measured.

The results are shown in Table 1.

The composition of the peroxide composition of this example is 32% by weight of ketone peroxide, 40% by weight of dilution stabilizer, 20% by weight of solubilizer, and 10% by weight of water.

In addition, the composition of the peroxide composition of the comparative example was 40% by weight of ketone peroxide, 30% by weight of dilution stabilizer, and 2% of solubilizer.
0% by weight and 10% by weight of water.

Procedures (Hoshosho - (spontaneous) July 8, 1985

Claims (1)

[Claims] 1. Peroxide used as an oxidizing agent when manufacturing a mold by injecting gaseous or aerosolized sulfur dioxide into a granular refractory aggregate mixture to which an acid-curable resin and an oxidizing agent have been added. A water-containing ketone peroxide composition containing a dilution stabilizer solubilized by a solubilizer to be homogeneous, and the proportion of each component is 20% by weight of ketone peroxide. A peroxide composition for molding, characterized in that the content is less than 35% by weight: 5 to 40% by weight of water, 10 to 50% by weight of dilution stabilizer, and 5 to 50% by weight of solubilizer. 2. The composition according to claim 1, wherein the ketone peroxide is at least one peroxide of an aliphatic ketone having 3 to 8 carbon atoms or a peroxide of an alicyclic ketone having 6 to 10 carbon atoms. 3. The solubilizer is a water-soluble monocarboxylic acid, a water-soluble hydroxy mono- or polycarboxylic acid, an acidic alkali metal salt of a polycarboxylic acid or a hydroxy-polycarboxylic acid, a water-soluble monoalcohol compound, a water-soluble lactone compound, The composition according to claim 1, which is at least one selected from the group of water-soluble ketone compounds, water-soluble ether compounds, water-soluble ester compounds, and water-soluble ether ester compounds. 4. The composition according to claim 3, wherein the hydroxy polycarboxylic acid has 2 to 6 carbon atoms. 5. The composition according to claim 3, wherein the acidic alkali metal salt of polycarboxylic acid or hydroxy polycarboxylic acid has 2 to 6 carbon atoms. 6. The composition according to claim 3, wherein the water-soluble monoalcohol has 1 to 6 carbon atoms. 7. The composition according to claim 1, wherein the dilution stabilizer is one or more of the compounds represented by the following [I] to [V]. [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, n is 1 to 3, and when n = 1, X is an alkyl group with 1 to 20 carbon atoms, an alkenyl group, an alkynyl group, a cycloalkyl group, It is an aryl group or an aralkyl group. When n = 2, X is an alkylene group having 2 to 20 carbon atoms, an alkenylene group,
Alkynylene group, cycloalkylene group, phenylene group,
It is an aralkylene group or an alkyl substituted product thereof. When n = 3, X is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼. For n = 1 to 3, all R_1 may be the same or different, and the total number of carbon atoms in R_1 is an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, an aralkyl group, or halogen, alkoxy, acyloxy, or alkoxycarbonyl substituted products thereof. ) [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, m is an integer from 1 to 300. Y is an alkylene group having 2 to 20 carbon atoms, an alkenylene group,
It is an alkynylene group, a phenylene group or an aralkylene group. R_2 and R_3 may be the same or different, and are an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, or aralkyl group having a total number of carbon atoms of 1 to 20. R_3 further includes a hydrogen atom and an acyl group. ) [III] Glycerin esters ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (In the formula, R_4, R_5, R_6 are hydrogen atoms, or alkyl groups, alkenyl groups whose total number of carbon atoms is 1 to 60,
It is an alkynyl group, a cycloalkyl group, an aryl group or an aralkyl group. However, at least one of R_4, R_5, and R_6 is not a hydrogen atom. ) [IV] Phosphorous esters ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (IV-1), ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (IV-2), or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼(IV-3) (In the formula, R_7, R_8, R_9 are hydrogen atoms, or alkyl groups having 1 to 20 carbon atoms, alkenyl groups, alkynyl groups,
An aryl group, an aralkyl group, or a halogen-, alkoxy-, or acyloxy-substituted product thereof. However, R_7
, R_8, and R_9 is not a hydrogen atom. ) [V] Saturated or unsaturated fatty acids having 12 to 24 carbon atoms, furfuryl alcohol, phenolic compounds, aliphatic or aromatic aldehyde compounds, furfuryl alcohol/formalin polycondensates, phenolic compounds/formalin polycondensates, Urea/formalin polycondensate, melamine/formalin condensate.