JPS61276740A - Peroxide composition for casting mold - Google Patents

Abstract

PURPOSE:To improve safety and to reduce the cost of production by constituting a ketone peroxide compsn. of the component ratios consisting of respectively specific weight % of ketone peroxide, water and the 1st and 2nd dilution stabilizers. CONSTITUTION:At least one kind of an aliphat. ketone of 3-8C and alicyclic ketone of 6-10C is oxidized by hydrogen peroxide water is the presence of an acid catalyst to form the ketone peroxide. The ketone peroxide compsn. is then formed by mixing 20-60% ketone peroxide, <5% water, 10-50% 1st dilution stabilizer and 5-50% 2nd dilution stabilizer by (weight %). The 1st dilution stabilizer is selected from various carbon compds. and the 2nd dilution stabilizer is selected from at least one kind of comps. such as alcohol and ketone. Since the compsn. in hydrous, the safety is improved and since the process for production is simple, the cost of production is reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an oxidizing agent used when forming a mold by adding sulfur dioxide to a granular refractory aggregate mixture containing an acid-curable resin and an oxidizing agent. It is related to. More specifically,
The present invention relates to certain 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. It has been used. All of these are usually baked and hardened at 200 to 300"C.
This results in energy consumption, curing time, mold distortion,
There were various problems such as poor dimensions of the castings due to deformation and the 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 and becoming popular as a molding method to overcome 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. Therefore, there are advantages such as fewer casting defects. However, this acid-curing cold box method requires the use of expensive organic peroxides as oxidizing agents, and there is also the problem of concerns about the stability of organic peroxides. Oxides are required.

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 the Problems] Under such circumstances, the present inventors have conducted intensive research and have invented a peroxide composition for curable molds that is inexpensive, highly safe, and has excellent performance. This is what we have come to.

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. Ketone peroxide 20-60% water by weight
less than 5% by weight of the first diluted stabilizer; 10-50% by weight of the second diluted stabilizer; 5-50% by weight of the first diluted stabilizer and the second diluted stabilizer. The present invention relates to a peroxide composition for molds, which is a ketone peroxide composition.

First dilution stabilizer One or more compounds represented by N) to (XI) below.

[I]0 X(-C-0-R,)ll (in the formula, n is 1 to 3, and when n = 1, group, aryl group or aralkyl group.

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.

In the case of n・3, for n=1 to 3, R1 is 1 even if they are all the same.
, may be different<, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, an aralkyl group, in which the sum of all the carbon numbers of R1 is n=60, or a halogen thereof, alkoxy, acyloxy,
It is an alkoxycarbonyl substituted product. ) [■]0 Rz-C-0(-Y-0-)-1? + (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,, 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 a furalkyl group having a total number of carbon atoms of 1 to 20.

R2 further includes a hydrogen atom and an acyl group. ) CDI) Glycerin esters (wherein Ra, Rs, and Rh are hydrogen atoms, or alkyl groups, alkenyl groups, alkynyl groups, cycloalkyl groups, aryl groups, or aralkyl groups having a total number of carbon atoms of 1 to 60) be.

However, a small number of R4, R5, and R6 (one of which is not a hydrogen atom) (IV) Phosphorus esters (in the formula, Rw, Rs, and R* are hydrogen atoms, or have 1 to 2 carbon atoms)
0 alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group, or a halogen-, alkoxy-, or acyloxy-substituted product thereof. However, R? +R11
At least one of +1 to 9 is not a hydrogen atom. )
(V) (In the formula, R1° and Ro are an alkyl group, alkenyl group, or alkynyl group having 1 to 20 carbon atoms.) (Vl) (In the formula, R1! and R13 are each an aliphatic group having 18 or less carbon atoms. (Hydrocarbon group or hydrogen atom.) [■] An aromatic compound in which the substituent attached to the benzene ring is one, two or more, or two or more types of each of a methoxy group, an aldehyde group, or a nitro group.

[■] Aliphatic hydrocarbon having 5 to 18 carbon atoms.

(IX) Saturated fatty acid with 1 to 22 carbon atoms or 5 carbon atoms
~22 unsaturated fatty acids.

(X) Alicyclic carboxylic acid having 5 to 40 carbon atoms.

(XI) Furfuryl alcohol, phenolic metal compound,
Aliphatic aldehyde compounds, furfuryl alcohol/formalin weight ratios, phenolic compounds/formalin polycondensates, urea/formalin polycondensates, melamine/formalin condensates.

Second dilution stabilizer At least one type selected from the group consisting of alcohol compounds, ketone compounds, and ether compounds.

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. This is a non-aqueous peroxide composition produced by separating the aqueous layer after completion of the process, and neutralizing, washing, drying, and purifying the non-aqueous layer. This product has a complicated manufacturing process)
Not only is it time-consuming, the yield is significantly lower considering the amount of raw materials used, and it is expensive, but it is 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, and does not contain the above-mentioned first
Contains a dilution stabilizer and a second dilution stabilizer, and has excellent performance as an oxidizing agent for the acid-curing cold box method. It does not require complicated manufacturing processes, is inexpensive, and is fire safe. Due to its excellent properties, it provides practically satisfactory results.

A preferred method for producing the 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 hydrogen peroxide solution over an acid catalyst. In this method, the ketone peroxide produced by oxidation is mixed with the first dilution stabilizer and the second dilution stabilizer described above.

The proportion of each component in the peroxide composition of the present invention is: ketone peroxide 20 to 60% by weight water
Less than 5% by weight first dilution stabilizer
10-50% by weight second dilution stabilizer 5
~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 10 and Comparative Examples 1 to 2 15 parts by weight of furan resin and 5 parts by weight of ketone peroxide compositions (water content 2% by weight) of the present invention and comparison were added to 1000 parts by weight of Australian flattery silica sand. The kneaded mixture was placed in a circular mold (for white smoke measurement, mold weight 6
0 kg), and then sulfur dioxide gas was injected into the mold filled with the mixture, followed by cleaning with clean air and forming a mold.

Molten metal at about 1420° C. was poured into the formed mold for measuring white smoke, and the time from the time of pouring until no white smoke came out was measured. The results are shown in Table 1.

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 composition comprising: ketone peroxide 20-60% by weight water less than 5% by weight the following first dilution stabilizer 10-50% by weight the following second
A peroxide composition for molding, characterized in that the ketone peroxide composition is diluted with a first dilution stabilizer and a second dilution stabilizer, the dilution stabilizer being 5 to 50% by weight. First dilution stabilizer One or two of the compounds represented by [I] to [XI] below
More than a species. [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, an alkynylene group, a cycloalkylene group, a phenylene group, 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, 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 a halogen, alkoxy, or acyloxy group thereof. , is an alkoxycarbonyl substituted product.) [II] ▲ Numerical formulas, chemical formulas, tables, etc. are available▼ (In the formula, m is an integer from 1 to 300. Y is an alkylene group, alkenylene group, or alkynylene having 2 to 20 carbon atoms. R_2 and R_3 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 alkyl group having a total number of carbon atoms of 1 to 20. It is an alkyl group. 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, and R_6 are hydrogen atoms or all carbon atoms is an alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group, or aralkyl group with a sum of 1 to 60. 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, alkenyl groups, alkynyl groups, aryl groups, aralkyl groups having 1 to 20 carbon atoms, or halogen, alkoxy, or acyloxy substituted products thereof. However, , R_7, R_8, R
At least one of _9 is not a hydrogen atom. ) [V] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R_1_0 and R_1_1 are alkyl groups, alkenyl groups, or alkynyl groups having 1 to 20 carbon atoms.) [VI] ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (In the formula, R_1_2 and R_1_3 each have a carbon number of 1
It is an aliphatic hydrocarbon group or hydrogen atom of 8 or less. ) [VII] An aromatic compound in which the substituent attached to the benzene ring is one, two or more, or two or more types of each of a methoxy group, an aldehyde group, or a nitro group. [VIII] Aliphatic hydrocarbon having 5 to 18 carbon atoms. [IX] Saturated fatty acids with 1 to 22 carbon atoms or 5 to 22 carbon atoms
22 unsaturated fatty acids. [X] Alicyclic carboxylic acid having 5 to 40 carbon atoms. [X I ] Furfuryl alcohol, phenolic compound, aliphatic aldehyde compound, furfuryl alcohol/formalin polycondensate, phenol compound/formalin polycondensate, urea/formalin polycondensate, melamine/formalin condensate. Second dilution stabilizer At least one type selected from the group consisting of alcohol compounds, ketone compounds, and ether compounds. 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.