JPH111682A - Antistatic agent for acrylic resin and acrylic resin composition using the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To exhibit excellent antistatic properties immediately after molding with a small amount of addition and maintain it for a long period of time.
Further, the present invention provides an antistatic agent for an acrylic resin which does not interfere with the operation during molding. SOLUTION: The antistatic agent for an acrylic resin of the present invention contains an alkylamine derivative (A) represented by the following chemical formula (Formula 1) and a fatty acid (B) having 8 to 22 carbon atoms. The weight ratio between the alkylamine derivative (A) and the fatty acid (B) is (A) / (B) = 9/1 to 1/9.
Is set in the range. Embedded image

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antistatic agent for an acrylic resin and an acrylic resin composition using the same, and more particularly, an antistatic property is immediately exhibited after molding and can be maintained for a long time. In addition, the present invention relates to an antistatic agent for an acrylic resin which does not impair the transparency and moldability of the acrylic resin, and an acrylic resin composition using the same.

[0002]

2. Description of the Related Art Acrylic resins are widely used as materials for films, fibers, molded products, etc. because of their excellent transparency and optical properties, and also excellent mechanical properties, processing properties and appearance. It is awarded for lighting fixtures, signboards, and ornaments. However, since this acrylic resin is generally hydrophobic and has a large electrical insulation property, it is easily charged by accumulation of static electricity. When the acrylic resin is charged, the appearance of the product may be impaired by the adhesion of dust,
There is a possibility that work efficiency in processes such as processing, packaging, printing, and painting may decrease. In addition, the accumulated electrostatic discharge may hinder the manufacturing operation of the acrylic resin product. In order to solve this problem, conventionally, various antistatic methods have been studied.

As general antistatic agents of internal addition type for synthetic resins, cationic, anionic and nonionic surfactants are known, and these surfactants have an antistatic effect. It is presumed to be expressed by bleeding out to the surface of the synthetic resin.

However, since the processing temperature of the acrylic resin is higher than that of other resins, the use of a cationic surfactant having poor thermal stability in the acrylic resin causes severe coloring and deterioration of resin properties.

[0005] As anionic surfactants for solving the problem of thermal stability, there are disclosed in Japanese Patent Application Laid-Open Nos. 49-73443, 52-47072 and 54-37154 alkyl metal sulfonates. Anionic surfactants such as salts and metal salts of alkyl benzene sulfonic acids have been proposed. However, these anionic surfactants have high hydrophilicity and are not sufficiently compatible with the hydrophobic acrylic resin, so that transparency, which is one of the features of the acrylic resin, is reduced, and the appearance is impaired. There is a problem.

In view of such circumstances, the present applicant has previously disclosed an acrylic resin composition having a stable antistatic property without impairing transparency (Japanese Patent Application No. 4-119).
948). However, when this was further examined, it was found that, in order to obtain a surface resistance value of 1 × 10 ¹² Ω or less, which is a criterion for antistatic performance, particularly for an injection-molded product, 2 × 10 ¹² Ω or less was required.
It has been found that a humidity control time of about 4 hours is required, and it is necessary to improve the effect in terms of immediate effect.

On the other hand, as a method for preventing static charge of an injection molded article of an acrylic resin, there is a method using a nonionic surfactant having a carbon chain length of 12 or less, and a method using lauric acid monoglyceride in combination with a higher alcohol ( Tokuhei 2-1
No. 4377), N, N-bis (hydroxyethyl)
A method of blending an alkylamine (JP-A-62-2959)
No. 44) has been proposed.

However, these methods have a problem that a sufficient antistatic effect is not immediately exhibited immediately after injection molding of an acrylic resin, similarly to the technique disclosed by the present applicant. In addition, since the nonionic surfactant has high volatility, a silver mark is generated on the surface of the molded product to impair the appearance of the molded product, and furthermore, there is a number of problems such as a large amount of smoke generated during molding and hindering the work. .

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an acrylic resin which exhibits excellent antistatic properties immediately after molding even if it is added in a small amount, and which maintains its long-lasting properties. An object of the present invention is to provide an antistatic agent for an acrylic resin, which does not impair the transparency and the like of the molded article, has a good surface condition of the molded article, and does not hinder the operation at the time of molding, and an acrylic resin composition using the same.

[0010]

In order to achieve the above object, an antistatic agent for an acrylic resin according to the present invention comprises an alkylamine derivative (A) represented by the aforementioned chemical formula (Chemical Formula 1) and a C8-C8 compound. And the fatty acid (B) is contained in a weight ratio of (A) / (B) = 9/1 to 1/9. It has a configuration that it is.

Further, the acrylic resin composition of the present invention comprises:
The acrylic resin antistatic agent is contained in a proportion of 0.3 to 6.0 parts by weight based on 100 parts by weight of the acrylic resin.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The alkylamine derivative (component A) according to the present invention is represented by the above formula (Formula 1).

Preferred examples of the alkylamine derivative include octyldiethanolamine, decyldiethanolamine, dodecyldiethanolamine, tetradecyldiethanolamine, hexadecyldiethanolamine, and octadecyldiethanolamine.
Particularly, dodecyldiethanolamine is preferred. These alkyldiethanolamines may be used alone or in combination of two or more.

Next, the fatty acids (component B) according to the present invention include straight-chain saturated fatty acids, branched saturated fatty acids, unsaturated fatty acids, resin acids and the like. Preferred examples of the fatty acid include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, linoleic acid, linolenic acid, stearic acid, isostearic acid, arachiic acid, behenic acid,
Examples thereof include 2-hydroxystearic acid and abietic acid, and particularly preferred are palmitic acid and stearic acid. These fatty acids may be used alone or in combination of two or more.

The weight ratio of the alkylamine derivative (component A) to the fatty acid (component B) is such that A / B = 9/1 to 1.
Must be 1/9. This is because the weight ratio is 9 /
If it exceeds 1, a silver mark will be formed on the molded article, and if it is less than 1/9, the antistatic performance will decrease. The preferred range of the weight ratio is 8/2 to 2
/ 8. The form of the antistatic agent of the present invention is not particularly limited, and may be a mixture in which the alkylamine derivative (A component) and the fatty acid (B component) are previously mixed, or may be mixed for the first time when the acrylic resin is compounded. It may be in a form. In addition, in the form of the mixture before blending,
The A component and the B component may be in an independent state, or may be in a melt-mixed state. The melt mixing can be performed, for example, by mixing at a temperature of 70 ° C. or higher.

Examples of the acrylic resin to which the antistatic agent of the present invention can be applied include, for example, methyl methacrylate homopolymer or methyl methacrylate, acrylate, methacrylate, acrylic acid, methacrylic acid, styrene, Copolymers with other monomers such as α-methylstyrene, acrylonitrile, butadiene and the like can be mentioned. In this copolymer, the proportion of other monomers is preferably 50% by weight or less. Examples of the acrylate include methyl acrylate, ethyl acrylate, and butyl acrylate. Examples of the methacrylate include ethyl methacrylate and butyl methacrylate.

Further, a rubber component, for example, polybutadiene, styrene-butadiene rubber, acrylonitrile-butadiene rubber, or the like can be blended with the acrylic resin in order to improve the strength of the molded product.

By blending the antistatic agent of the present invention with an acrylic resin, an acrylic resin composition having excellent properties such as antistatic properties, transparency and moldability is prepared. In this case, the compounding amount of the antistatic agent is such that the total of the components (A) and (B) is 0.3 to 6.0 parts by weight based on 100 parts by weight of the acrylic resin in the case of ordinary use. The range is preferably 0.5 to 4.0 parts by weight. this is,
If the amount is less than 0.3 parts by weight, the antistatic property may not be sufficiently exhibited. If the amount exceeds 6.0 parts by weight, the improvement of the antistatic effect corresponding to the compounding amount cannot be obtained, and the physical properties of the acrylic resin are adversely affected. This is because there is a possibility that it may be exerted.

The acrylic resin composition of the present invention can be prepared by, for example, kneading the antistatic agent into the acrylic resin and adding the same. As described above, as described above, the alkylamine derivative (component A) and the fatty acid (component B) may be separately added to the acrylic resin, or the components A and B may be added separately. It may be added in a state of being melt-mixed. The kneading method is not particularly limited, and may be a conventionally known method, for example, a method in which an acrylic resin and the antistatic agent are blended and then melt-kneaded with an extruder, or the antistatic agent is previously mixed with the acrylic resin. And a method of preparing a master batch kneaded at a high concentration and diluting it at the time of molding.

In preparing the acrylic resin composition, various commonly used additives can be blended as required. Examples of such additional components include phosphorus-based antioxidants such as trisnonylphenyl phosphite and triphenyl phosphite, dioctadecyl 3,3'-thiodipropionate, and didodecyl 3,3'-thiodipropionate. Sulfur-based antioxidants, butylated hydroxytoluene, tetrakis [methylene-3- (3 ′, 5 ′)
-Di-t-butyl-4'-hydroxyphenyl) propionate] a phenolic antioxidant such as methane, a UV absorber, an ethylenebisamide, a monoalkylamide, a montanic acid wax, a polyolefin wax, a lubricant such as a fatty acid metal salt, Examples include oxazole-based and coumarin-based fluorescent whitening agents, resin strength reinforcement such as barium sulfate, titanium oxide, and calcium carbonate, light-scattering inorganic fillers, and coloring agents. The proportions of these are not particularly limited as long as the properties of the antistatic agent and the acrylic resin of the present invention are not impaired. In addition, other known antistatic agents for acrylic resins can be used in combination to the extent that properties such as transparency are not impaired.

The acrylic resin composition of the present invention can be formed into a predetermined molded product by various molding methods such as injection molding, extrusion molding, and blow molding.
Covers and parts for lighting fixtures, electric meters, electronic devices, etc.
It is suitably used as a molded article material such as a meter cover, a film, a sheet, a panel, and a fiber.

[0022]

Next, examples will be described together with comparative examples.

(Examples 1 to 17, Comparative Examples 1 and 2) Each type of antistatic agent shown in the following Table 1 and weight ratio was added to an acrylic resin (HR, manufactured by Kuraray Co., Ltd.). And premixed with a Henschel mixer to obtain a mixture. This mixture was converted to 23 using a vented twin-screw extruder.
The mixture was melt-kneaded at 0 ° C. to obtain a trend. At that time, the degree of smoke emission from the vent was visually checked. The antistatic agent is a mixture of the component A and the component B in advance.

Next, the obtained strand was cut with a pelletizer and pelletized. This pellet is
After drying at 4 ° C. for 4 hours, injection molding was performed at 240 ° C. using an injection molding machine to prepare a 100 × 100 × 2 mm plate-shaped test piece. Immediately after the preparation of the test piece and one month after the preparation, the surface resistance was measured under the conditions of a temperature of 20 ° C. and a humidity of 65% RH, and the antistatic performance was evaluated. Further, the degree of silver mark generation and the degree of stickiness on the surface of the test piece were visually evaluated by sensory evaluation. The results are shown in Table 1 below. The antistatic performance, the degree of silver mark generation, and the degree of stickiness were examined by the following methods.

(Antistatic Performance) The surface resistivity of the test piece was measured with a hyper-insulation meter (SME-10, manufactured by Toa Denpasha Co., Ltd.). The antistatic performance was evaluated. ◎: 1 × 10 ¹¹ ≦ X <1 × 10 ¹² ： １: 1 × 10 ¹² ≦ X <1 × 10 ¹³ ×: X ≧ 1 × 10 ¹³

(Degree of Silver Mark Occurrence) Evaluation was made according to the following criteria. In addition, a good grade is evaluated as "good" or more. A: There is no silver mark. ：: There is almost no silver mark. Δ: There are some silver marks. ×: There are considerable silver marks.

(Degree of stickiness) Evaluation was made according to the following criteria. In addition, a good grade is evaluated as "good" or more. ◎: There is no stickiness at all. ：: Almost no stickiness. Δ: Slight stickiness. ×: There is considerable stickiness.

[0028]

[Table 1] AB weight ratio Addition amount Antistatic performance Silver solid Total component Component A / B (wt%) Immediately after molding One month after Marking Evaluation Example 1 a-2 b-3 1/9 1.5 ○ ○ ◎ ◎ ○ Example 2 a-2 b-3 2/8 1.5 ○ 〜 ◎ ○ 〜 ◎ ◎ ◎ Example 3 a-2 b-3 3/7 1.5 ◎ ◎ ◎ ◎ ◎ Example 4 a-2 b-3 5/5 1.5 ◎ ◎ ◎ ◎ ◎ Example 5 a-2 b-3 7/3 1.5 ◎ ◎ ◎ ◎ ◎ Example 6 a-2 b-3 9/1 1.5 ◎ ◎ ○ ◎ ○ Example 7 a- 2 b-3 4/6 0.3 ○ ○ ◎ ◎ ○ Example 8 a-2 b-3 4/6 1.5 ◎ ◎ ◎ ◎ ◎ Example 9 a-2 b-3 4/6 6.0 ◎ ◎ ◎ ○ ○ Example 10 a-1 b-1 5/5 1.5 ○ ◎ ◎ ◎ ○ Example 11 a-1 b-3 4/6 1.5 ○ ◎ ◎ ◎ ○ Example 12 a-1 b-4 4/6 1.5 ○ ◎ ◎ ◎ ○ Example 13 a-2 b-2 4/6 1.5 ◎ ◎ ◎ ◎ ◎ Example 14 a-2 b-4 4/6 1.5 ○ ◎ ◎ ◎ ○ Example 15 a-3 b-1 4 / 6 1.5 ○ ◎ ◎ ◎ ○ Example 16 a-3 b-3 4/6 1.5 ○ ◎ ◎ ◎ ○ Example 17 a-3 b-4 4/6 1.5 ○ ◎ ◎ ◎ ○ Comparative Example 1 a-2 b-3 0.5 / 9.5 1.5 × × ◎ ◎ × Comparative Example 2 a-2 b-3 9.5 / 0.5 1.5 ◎ ◎ × ○ × a-1: octyldiethanolamine b-1: caprylic acid a-2: dodecyldiethanolamine b-2: palmitic acid a-3: octadecyldiethanolamine b-3: stearic acid b-4: behenic acid

From the above Table 1, it can be seen that in the examples using the predetermined antistatic agent of the present invention, excellent antistatic properties are exhibited immediately after molding with a small amount of addition, and that the antistatic properties are maintained for a long period of one month. It persisted, and there was no silver mark on the molded product (test piece) without stickiness. Further, in the examples, no smoke was generated at the time of molding, and the transparency of the acrylic resin was excellent. On the other hand, in Comparative Example 1, the antistatic property was poor, and in Comparative Example 2, the surface condition of the molded article was poor.

[0030]

As described above, when the antistatic agent for an acrylic resin of the present invention is applied, excellent properties can be obtained immediately after molding with a small amount of addition without impairing various properties such as transparency of the acrylic resin. The antistatic properties can be imparted to the acrylic resin for a long period of time, and there is no problem such as smoking during molding, and the surface of the molded product is good without generation of silver marks and the like. Therefore, the molded article of the acrylic resin composition using the antistatic agent for acrylic resin of the present invention has no problem such as adhesion of dust due to electrification, and has a good surface state without generation of a silver mark or the like. Also, the feel and appearance are excellent.

Claims (2)

[Claims] 1. An alkylamine derivative (A) represented by the following chemical formula (Chem. 1) and a fatty acid (B) having 8 to 22 carbon atoms, wherein the alkylamine derivative (A) and the fatty acid (B) ) And (A) / (B) = 9 /
An antistatic agent for an acrylic resin set in the range of 1 to 1/9. Embedded image 2. The acrylic resin antistatic agent according to claim 1 is used in an amount of 0.3 to 100 parts by weight of the acrylic resin.
An acrylic resin composition containing 6.0 parts by weight.