JP2003034754A - Method for preparing emulsion and suspension of stabilizing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a high temperature and/or a long-time stirring are required to prepare the emulsion and/or dispersion of a phenol-based stabilizing agent of high melting point and also to improve the stability of the emulsion and/or dispersion left standing. SOLUTION: A method for preparing the emulsion and/or dispersion of a stabilizing agent in which a phenol-based stabilizing agent having its melting point of at least 90 deg.C and a sulfur-based stabilizing agent or these stabilizing agents and water in at most half an amount (weight) of the phenol-based stabilizing agent are liquidized at a temperature of lower than the melting point of the phenol-based stabilizing agent, and then an emulsifier and/or a dispersant are combined. It is possible to liquidize the phenol-based stabilizing agent of high melting point at a temperature of lower than the melting point, and the preparations of the emulsion and/or dispersion of the stabilizing agent are possible at a comparatively low temperature. The emulsion and/or dispersion concerned are suitably used as a stabilizing agent for synthetic resins, particularly rubber-reinforced styrene-based resins.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for preparing an emulsion / dispersion liquid of a stabilizer used in a synthetic resin.

[0002]

2. Description of the Related Art Generally, ABS resin, AAS resin, MBS
Rubber-reinforced styrene-based resin known by the name of resin,
It has an excellent balance of mechanical properties and workability, and is used in a wide range of fields such as vehicles, home appliances, and office automation equipment. As a method for producing these rubber-reinforced styrenic resins, emulsion polymerization method, suspension polymerization method, solution polymerization method, bulk polymerization method, and further a combination thereof are known. Legal is used a lot.

The rubber-reinforced styrenic resin polymerized by these emulsion polymerizations usually becomes vehicle parts and electric parts through various steps such as salting out, recovery, drying, granulation and molding. Thus, the rubber-reinforced styrene-based resin is exposed to a high temperature before the final molded product is obtained. Further, even after being incorporated as a molded product into a part of an automobile or an electric product, it is exposed to a high temperature environment.

For this reason, various stabilizers such as an antioxidant, a light stabilizer, and an ultraviolet absorber are blended with the rubber-reinforced styrene resin. In general emulsion polymerization, after the completion of polymerization, steps such as salting out, recovery, drying, and granulation are required as described above, but in that case, they are often exposed to high temperatures, and in view of preventing deterioration in these steps. It is common to add an antioxidant to the rubber-reinforced styrene-based resin in an emulsified state, but since the rubber-reinforced styrene-based resin is in an emulsified state, the stabilizer to be added must also be an emulsified system or a dispersion system. If it is difficult to handle.

On the other hand, in order to meet higher requirements, development of new compounds for such stabilizers and combination of existing compounds have been proposed. For example, steric hindrance structuring (hindered structure) has been proposed to enhance the action and effect. ) And / or high molecular weight, and the melting point thereof is also increasing accordingly. Therefore, it has been difficult to easily emulsify the stabilizer as before.

For example, there is disclosed a method of preparing a hindered phenol stabilizer having a melting point of 115 ° C. together with a dispersant and casein in a ball mill in 6 hours to form a dispersion.
It has a problem that it takes a long time to disperse and has poor leaving stability (separation).

[0007]

The present invention solves the problem that a high melting point phenolic stabilizer must be stirred at a high temperature and / or for a long time when it is emulsified / dispersed. Is intended to improve storage stability.

[0008]

Means for Solving the Problems The present inventors have raised the temperature of a high-melting-point phenolic stabilizer (solid) together with a sulfur-based stabilizer, without heating to the melting point of the phenol-based stabilizer, The present inventors have found that they can be liquefied at a relatively low temperature, and have reached the present invention.

That is, according to the present invention, (1) a phenolic stabilizer having a melting point of 90 ° C. or higher and a sulfur-based stabilizer or water thereof and ½ weight or less of the phenolic stabilizer are added to the phenolic stabilizer. A method for preparing a stable emulsion / dispersion, which comprises liquefying at a temperature lower than the melting point and then mixing water with an emulsifier and / or a dispersant, (2) Phenolic stability with a melting point of 90 ° C. or higher The agent and the sulfur-based stabilizer and at least a part or all of the emulsifier and / or the dispersant are liquefied at a temperature lower than the melting point of the phenol-based stabilizer, and then the remaining emulsifier and / or the dispersant and water are removed. A method of preparing a stabilizer emulsion, characterized by being blended, (3) The ratio (weight) of phenolic stabilizer: sulfuric stabilizer is 1: 0.3 to 10 (1) or (2).
It is intended to provide a method of preparing an emulsion / dispersion of the described stabilizer.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The phenolic stabilizer used in the present invention is a compound having a melting point of 90 ° C. or higher, for example, p-
Butylated reaction product of cresol and dicyclopentadiene (melting point 115 ° C, average molecular weight 600 to 700), 4,
4'thiobis 3 methyl 6 tertiary butyl phenol (melting point 160 ° C, molecular weight 359), 4,4 'butylidene bis 3 methyl 6 tertiary butyl phenol (melting point 20
9 ° C., molecular weight 383), 2,2 ′ methylenebis 4 methyl 6 tertiary butylphenol (melting point 128 ° C., molecular weight 341), and the like, and one or more kinds can be used. In particular, it is preferably a sterically hindered structure (hindered) and has an average molecular weight of 500 or more. For example, a butylated reaction product of p-cresol and dicyclopentadiene (trade name: Good Year product name: Wingsta
y L) is illustrated.

The sulfur-based stabilizer is dilauryl 3,
3'-thiopropionate, dimistyl 3,3 'thiopropionate, distearyl 3,3'-thiopropionate, pentaerythyl tetrakis 3-lauryl thiopropionate, ditridecyl 3,3'-thiopropionate Pionate, 2-mercaptobenzimidazole, 2-tetrabutyl 6-3-tert-butyl 2-hydroxy-5-methylbenzoyl-4-methylphenyl acrylate, 2
-1--2-hydroxy-3,5-ditertiary pentylpenylethyl 4,6-ditertiary pentylpenyl acrylate and the like can be mentioned, and one kind or two or more kinds can be used. Particularly, dilauryl 3,3 ′ thiopropionate is preferable.

In addition to the above-mentioned specific stabilizers, phosphorus-based stabilizers such as trisnolylphenyl phosphite, triphenyl phosphite, tris 2,4 dibutylphenyl phosphite, which are known stabilizers other than those, and alkylation Amine stabilizers such as diphenylamine, and 2,
6 ditertiary butyl 4-methyl henol (melting point 69
° C), n-octadodecyl 3-3,5 ditertiary hydroxyphenyl propionate (melting point 49-54
It is also possible to appropriately mix a low melting point phenolic stabilizer such as an alkylated bisphenol which is liquid at room temperature.

In the present invention, the above-mentioned specific stabilizer can be liquefied at a temperature (normal pressure) below the melting point of the phenolic stabilizer. There is no limitation on the heating method, and it does not matter whether it is direct or indirect. Of course, it can be liquefied by heating above the melting point of the phenolic stabilizer, but it requires energy and time, which is not only disadvantageous, but also requires extremely careful handling because it is extremely hot. .

The blending ratio of the phenolic stabilizer and the sulfurous stabilizer is not particularly limited, but the aspects such as the relationship between the temperature and time required for liquefaction of both components and the stabilizing effect required for the rubber-reinforced styrene resin are considered. Therefore, it is preferable that the weight ratio of the phenolic stabilizer: sulfuric stabilizer = 1: 0.3-10, and particularly the phenolic stabilizer: sulfuric stabilizer = 1: 0.3-3.0. Most preferably.

The emulsifier and dispersant usable in the present invention include known compounds. For example, as an emulsifier, an anionic emulsifier such as an alkali metal salt of a carboxylic acid such as rosin acid or a higher fatty acid, an alkali metal salt of an alkylsulfate, an alkali metal salt of an alkylsulfonic acid, or a nonionic such as a polyoxyalkylene alkyl ether. Examples of system emulsifiers, as the dispersant, polyvinyl alcohol,
Examples thereof include polyalkylene oxide, sodium polyacrylate, and methyl cellulose, which can be used alone or in combination. The amount of these emulsifiers and dispersants used is sufficient to be the minimum amount required to emulsify or disperse the mixed liquid of the above-mentioned phenol-based stabilizer and sulfur-based stabilizer. Generally, the total amount of the emulsifier and the dispersant is 1 to 70 parts by weight per 100 parts by weight of the total amount of the phenol-based stabilizer and the sulfur-based stabilizer.

The emulsion or dispersion of such stabilizers is diluted with water to a suitable concentration when used.
Generally, it is 10 to 70% by weight.

The equipment for preparing the above-mentioned emulsion / dispersion is not particularly limited, and a phenol-based stabilizer, a sulfur-based stabilizer, an emulsifier and / or a dispersant, which are essential components in the present invention,
Also, any equipment that can add, heat, mix (stir), and discharge water may be used.

If desired, the emulsion / dispersion liquid of the present invention may further contain various compounds such as benzophenone-based, benzotriazole-based, benzoate-based, salicylate-based, and cyanoacrylate-based UV absorbers. is there.

The emulsion / dispersion liquid of the present invention is added to an emulsion liquid of a rubber-reinforced styrene resin produced by emulsion polymerization of ABS resin, AAS resin, AES resin, MBS resin, etc., and then salting out / recovering The rubber-reinforced styrene resin is obtained through processes such as drying and granulation. These resins are
Like conventional resins, it is suitable for use in vehicles, electricity, etc.

[0020]

[Example] Next stabilizer emulsion (solid content: about 30% by weight)
Embodiments of the present invention will be described with reference to Examples and Comparative Examples. -Stabilizer Emulsion- Phenol-based stabilizer: 1.0 part Sulfur-based stabilizer: 1.0 part Emulsifier: 0.3 part Water: 5.4 parts

The compounds used are as follows. Phenolic stabilizer : Win made by Good Year
gstay L (butylated reaction product of p-cresol and dicyclopentadiene) (melting point: 115 ° C., average molecular weight: 60)
0-700). Sulfur-based stabilizer : DTPL (dilauryl 3,3 ′ thiopropionate) manufactured by Yoshitomi Pharmaceutical Co., Ltd. Emulsifier : Emulgen 109P (polyoxyethylene lauryl ether) manufactured by Kao Corporation.

Example 1 A phenol-based stabilizer (powder) and a sulfur-based stabilizer (powder) were all charged into a SUS kettle equipped with a jacket having an inner volume of about 1 cubic meter, a thermometer and a stirrer ( Outside temperature is 24 ° C). Steam was passed through the jacket to start heating, and stirring was started with a stirrer 5 minutes after the start of heating. Then, the content was completely liquefied in about 30 minutes (the temperature of the content was 91 ° C). After the complete liquefaction, the total amount of the emulsifier (liquid) was added while the stirring was continued (the temperature of the content was 70 ° C). Further, the entire amount of water was added and stirring was continued for 10 minutes. As a result, a stable emulsion (65 ° C.) was obtained about 50 minutes after starting the introduction of the phenolic stabilizer. Put the obtained stabilizer emulsion into a 500 ml graduated cylinder,
It was left at room temperature for 24 hours, and after standing, the presence or absence of liquid separation was confirmed, but no separation was observed at all.

Example 2 A phenol-type stabilizer (powder) and a sulfur-type stabilizer (powder) were added to a SUS kettle equipped with a jacket having an internal volume of about 1 cubic meter, a thermometer, and a stirrer, and the total amount of Water of 1/3 weight of the phenolic stabilizer was added (outside temperature 24 ° C.). Steam was passed through the jacket to start heating, and stirring was started with a stirrer 5 minutes after the start of heating. Then, the content was completely liquefied in about 30 minutes (the temperature of the content was 91 ° C). After complete liquefaction, the total amount of the emulsifier (liquid) was added while continuing stirring (the temperature of the contents was 70 ° C). Furthermore, the remaining water was added and stirring was continued for 10 minutes. As a result, about 50 after starting the introduction of the phenolic stabilizer
A stable emulsion (65 ° C.) was obtained in minutes. The obtained stabilizer emulsion was put in a 500 ml graduated cylinder, left standing at room temperature for 24 hours, and after standing, it was confirmed whether or not the solution was separated, but no separation was observed at all.

[Example 3] A phenol-based stabilizer (powder), a sulfur-based stabilizer (powder) and an emulsifier were all added to a SUS kettle equipped with a jacket having an internal volume of about 1 cubic meter, a thermometer and a stirrer. It was put in (outside temperature 24 ° C). Pass steam through the jacket, start heating, start heating 5
From the minute, stirring was started with a stirrer. Then, the content was completely liquefied in about 30 minutes (the temperature of the content was 91 ° C). After complete liquefaction, the total amount of water was added while continuing stirring (the temperature of the contents was 70 ° C). As a result, a stable emulsion (65 ° C.) was obtained about 50 minutes after starting the introduction of the phenolic stabilizer. Put the obtained emulsion into a 500 ml graduated cylinder,
It was left at room temperature for 24 hours, and after standing, the presence or absence of liquid separation was confirmed, but no separation was observed at all.

Comparative Example 1 Only a phenolic stabilizer (powder) was charged into an SUS kettle equipped with a jacket having an internal volume of about 1 cubic meter, a thermometer and a stirrer (outside temperature 24
C). Steam was passed through the jacket, heating was started, and stirring was started with a stirrer from 5 minutes after starting heating, but it took 60 minutes until the content was completely liquefied (the temperature of the content was 116
C). Then, the sulfur stabilizer (powder), the emulsifier, and water were all added while stirring, but it took an additional 30 minutes to obtain an emulsion (65 ° C.). result,
After starting the introduction of the phenolic stabilizer, a stable emulsion (65
It took about 90 minutes to obtain (° C.). However, the leaving stability was evaluated as in the example, but no separation was observed.

Comparative Example 2 A phenolic stabilizer (powder), a sulfur stabilizer (powder), an emulsifier (liquid) and water were placed in a SUS kettle equipped with a jacket having an internal volume of about 1 cubic meter, a thermometer and a stirrer. , The total amount of each was added (outside temperature 24 ° C.). Steam was passed through the jacket to start heating, and stirring was started with a stirrer 5 minutes after the start of heating. afterwards,
Stirring was continued for about 60 minutes until the temperature of the contents reached 116 ° C. and then for about 30 minutes (total about 90 minutes), but the undispersed “damage” remained. When the standing stability was evaluated in the same manner as in the examples, separation (upper layer 40 mm) and "damage" were observed.

0.3 parts by weight of the various stabilizers prepared in Examples 1 to 3 and Comparative Example 1 were mixed with ABS resin (emulsified state) having a rubber content of 15% by weight per 100 parts by weight of solid content, The mixture was stirred, subjected to usual salting-out, drying and granulation steps, and pelletized. Various test pieces were molded from the obtained pellets, and the mechanical, thermal and optical properties were evaluated, but all were almost the same, and there was no problem in using as an ABS resin.

[0028]

As described above, by adopting the method of the present invention, it becomes possible to liquefy a phenolic stabilizer having a high melting point at a temperature below its melting point, and at a relatively low temperature for a short time. Can prepare an emulsion / dispersion liquid of the stabilizer.

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Claims (3)

[Claims] 1. A phenol-based stabilizer having a melting point of 90 ° C. or higher and a sulfur-based stabilizer or those and a phenol-based stabilizer (weight).
Emulsification / dispersion of a stabilizer, characterized by liquefying less than 1/2 of water with a temperature below the melting point of the phenolic stabilizer, and then blending water with an emulsifier and / or a dispersant. How to prepare a liquid. 2. A phenolic stabilizer having a melting point of 90 ° C. or higher, a sulfur-based stabilizer and at least a part or all of an emulsifier and / or a dispersant are liquefied at a temperature lower than the melting point of the phenolic stabilizer. Then the remaining emulsifier and / or
Alternatively, a method of preparing an emulsion / dispersion liquid of a stabilizer, which comprises mixing a dispersant and water. 3. A method for preparing an emulsion / dispersion liquid of a stabilizer according to claim 1, wherein the ratio (weight) of the phenol stabilizer: sulfur stabilizer is 1: 0.3 to 10.