JPS61276736A - Peroxide composition for casting mold - Google Patents

Abstract

PURPOSE:To provide the reduction of a production cost, the improvement of safety, etc. by constituting a peroxide compsn. or respectively specific weight % of ketone peroxide, water, dilution stabilizer and solubilizer. CONSTITUTION:The ketone peroxide is at least one kind of 1 kind of the ketone peroxide of an aliphat. ketone having 3-8C and alicyclic ketone of 6-10C. The peroxide compsn. is constituted of the components consisting of 35-60wt% ketone peroxide, 5-40wt% water, 10-60wt% dilution stabilizer and 5-40wt% solubilizer and is used as the oxidizer for an acid curable cold box method. The moisture content is increased and the laborious process for production is simplified by the above-mentioned method and therefore the cost of production is reduced and the safety against a fire, etc. is improved.

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 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 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 viscosity. Since it is used as a binder, it has advantages such as fewer defects in castings.However, this acid-curing cold box method requires the use of expensive organic peroxides as oxidizing agents, and the stability of organic peroxides is low. There is a problem with sexual anxiety, and 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 Problem C] 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. A water-containing ketone peroxide composition containing a dilution stabilizer homogeneously solubilized with at least one solubilizer selected from the group consisting of water-soluble ether compounds and water-soluble ester compounds. The present invention relates to a peroxide composition for molds, which is characterized in that it is a peroxide composition.

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. 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 an acid-curing cold box. It has excellent performance as an oxidizing agent in the law, does not require complicated manufacturing processes, is inexpensive, and has excellent fire safety due to its water content, providing practically satisfactory results. It is something.

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

The solubilizing agent used in the present invention is at least one selected from the group consisting of water-soluble ether compounds and water-soluble ester compounds, and includes, for example, dioxane, tetrahydrofuran, phosphate ester, acetate ester, and the like.

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

[I] 0 X(-C-0-R1).

(In the formula, 1 is 1 to 3, and when n = 1, X is an alkyl group having 1 to 20 carbon atoms, alkenyl
alkynyl group, cycloalkyl group, aryl group or 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 0CCt(.

Regarding n・1 to 3, R1 may be the same or different. It is an alkyl group, or a halogen, alkoxy, acyloxy, or alkoxycarbonyl substituted product thereof. ) [■] OR Tomi-C-0(4-0-)-Ri (In the formula, l 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.

R2 and R3 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.

R1 further includes a hydrogen atom and an acyl group. ) (I [I) Glycerin esters CHz-0-C-R4 CH-0-C-Rs CHz-0-C-Rh (In the formula, R4 and R1Rh are hydrogen atoms, or the sum of all carbon numbers is 1 to 60 alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group or aralkyl group.

However, at least one of Ra, Rs, and Rh is not a hydrogen atom. ) (IVI phosphorus esters (in the formula, Rt, Rs, R*' are hydrogen atoms, or have 1 to 1 carbon atoms)
20 alkyl groups, alkenyl groups, alkynyl groups, aryl groups, aralkyl groups, or halogen-, alkoxy-, or acyloxy-substituted products thereof. However, R? ,R
At least one of 11 and R9 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/
Volf 9F polycondensate, phenolic compound/formalin polycondensate, urea/formalin polycondensate, melamine/formalin condensate.

The proportions of each component in the peroxide composition of the present invention are: ketone peroxide, 35 to 60% water by weight;
5-40% by weight dilution stabilizer 10
~60wt% solubilizer 5~40wt%
is common.

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 4 and Comparative Examples 1 to 2 Hydrous ketone peroxide of the present invention and comparison containing 50% by weight of ketone peroxide, 20% by weight of dilution stabilizer, 10% by weight of solubilizer, and 20% by weight of water. In order to evaluate the performance of the oxide composition as an oxidizing agent in the acid-curing cold box method, molds were molded and the mechanical properties of the molds were investigated.

A mixture of 1,000 parts by weight of Australian flattery silica sand, 12 parts by weight of furan resin, and 5 parts by weight of peroxide composition was added and kneaded at 25 x 25 x 250 m/m.
The mold was filled into a mold, gaseous sulfur dioxide was blown into the mold, and the mixture was cleaned with compressed air to form a mold. After molding, the bending strength of the mold was measured over time.

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 water-containing ketone permeate composition containing a dilution stabilizer homogeneously solubilized with at least one solubilizer selected from the group consisting of water-soluble ether compounds and water-soluble ester compounds. A peroxide composition for molds, which is an oxide composition. 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 composition according to claim 1, wherein the dilution stabilizer is one or more of the compounds represented by [I] to [V] below. [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] 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. 5. The proportions of each component are as follows: Ketone peroxide 35-60% by weight Water 5-40% by weight Dilution stabilizer 10-60% by weight Solubilizer 5-40% by weight Composition.