JP2001146547A - Antistatic agent composition and saturated polyester resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antistatic agent capable of producing a saturated polyester resin excellent in antistatic property while keeping transparency without causing whitening of the surface of a resin fabricated product, and to obtain a saturated polyester resin composition containing the same. SOLUTION: The antistatic agent composition is a mixture comprising 90-10 wt.% monoglyceride having a 12-22C constituent aliphatic acid and 10-90 wt.% diglyceride aliphatic acid ester having a 12-22C constituent aliphatic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antistatic agent composition and a saturated polyester resin composition, and more particularly to an antistatic agent composition which provides a saturated polyester resin composition having good transparency and excellent antistatic properties. And a saturated polyester resin composition containing the same.

[0002]

2. Description of the Related Art In recent years, various synthetic resins such as olefin resin, styrene resin or polyvinyl chloride resin have been developed, and are widely used by various methods such as extrusion, calendering, injection molding, vacuum molding or blow molding. Used in However, most of these resins are liable to generate static electricity, and therefore have a problem that dust adheres to the surface and becomes dirty to impair the appearance, and as a preventive measure, a method of kneading an antistatic agent is generally used. It has been done.

[0003] As an antistatic agent for these resins, ionic surfactants such as anionic, cationic and amphoteric surfactants, or nonionic surfactants are used depending on the type of resin and required properties. Have been.

[0004] Saturated polyester resins such as polyethylene terephthalate (PET) and a copolymer of terephthalic acid, ethylene glycol and 1,4-cyclohexanedimethanol (PET-G) are known for their transparency, mechanical properties, chemical resistance or heat resistance. Due to its excellent physical properties, it has come to be widely used as a material for films, fibers, molded products and the like. However, these saturated polyester resins, like other synthetic resins, have a problem that static electricity is liable to be generated.Therefore, dirt due to the adhesion of dust causes damage to the appearance, and unpleasant impact on the human body due to electric discharge. They also have the danger of causing disasters such as fires and explosions.

In order to overcome such a drawback that a saturated polyester resin is liable to generate static electricity, various antistatic agents have been conventionally studied. For example, a metal salt of an alkylbenzenesulfonic acid or a metal salt of an alkylsulfonic acid is incorporated. The method is described in JP-A-49-73443 and JP-A-52-73443.
Nos. 47072, 54-37154, 54
No. 15950 and the like.

[0006]

However, alkylbenzenesulfonic acid and metal salts of alkylsulfonic acid have poor compatibility with the saturated polyester resin, and the appearance of the saturated polyester resin molded article to which these salts are added is caused by whitening of the surface. There is a problem that causes a defect. Further, metal salts of alkyl benzene sulfonic acid and metal salts of alkyl sulfonic acid have poor thermal stability, and may cause coloring or decomposition of the resin during processing of the resin to which they are added.

[0007] The present invention relates to an antistatic agent capable of producing a saturated polyester resin which is transparent and maintains excellent antistatic properties without whitening the surface of a resin processed product, and an antistatic agent for the same. It is intended to provide a saturated polyester resin composition containing the same.

[0008]

Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies to develop an antistatic agent having good compatibility with a saturated polyester resin and excellent antistatic properties.
It is composed of a mixture of 90 to 10% by weight of monoglyceride having 12 to 22 carbon atoms of fatty acid constituting the ester and 10 to 90% by weight of diglycerin fatty acid ester having 12 to 22 carbon atoms of fatty acid forming the ester. The composition was used as an antistatic agent, and the ester mixture composition was used in an amount of 0.05 to 100 parts by weight of the saturated polyester resin.
The inventors have found that the problem can be solved by adding from 10 to 10 parts by weight, thereby completing the present invention.

As described above, as an antistatic agent for a synthetic resin, an ionic surfactant such as an anionic, cationic or amphoteric surfactant, or a nonionic surfactant depends on the type of the resin and the properties required. Have been used accordingly.

In these, as anionic surfactants, fatty acid salts, higher alcohol sulfates,
Fatty alcohol phosphate esters and alkyl allyl sulfonates are available, but these anionic surfactants have poor compatibility with a saturated polyester resin, so that the resin is whitened and the transparency is impaired.
Cationic surfactants include fatty acid amine salts, quaternary ammonium salts and alkylpyrridinium salts, and amphoteric surfactant systems include betaines and aliphatic amine sulfates. Activated surfactants have poor thermal stability and tend to yellow the resin by heating during processing.

As described above, anionic, cationic and amphoteric surfactants are not suitable as antistatic agents for saturated polyester resins.

On the other hand, examples of the nonionic surfactant include an alkyl ether type, an alkyl allyl ether type, an alkyl ester ether type, a polyhydric alcohol alkyl ester ether type and a polyhydric alcohol ester type, and the ether type is a saturated polyester. Poor compatibility with resin, and insufficient antistatic properties. In the polyhydric alcohol ester type, polyglycerol fatty acid esters having a high degree of condensation of sucrose fatty acid ester and glycerin have poor compatibility with the saturated polyester resin and are not suitable as an antistatic agent for the saturated polyester resin.

Since the other polyhydric alcohol ester type surfactants are the same ester, their compatibility with the saturated polyester resin is better than other surfactants. Among these polyhydric alcohol ester type surfactants, sorbitan fatty acid esters have poor heating stability and have a problem of coloring of resins, and propylene glycol fatty acid esters have good compatibility but poor antistatic properties. There are advantages and disadvantages depending on the structure of the ester.

The present inventors have focused on the compatibility between these polyhydric alcohol fatty acid esters and saturated polyester resins, and as a result of earnestly examining the effects of these esters,
By using a mixture of monoglyceride and diglycerin fatty acid ester, it has been found that an excellent antistatic effect can be obtained without impairing the transparency of the saturated polyester resin, thereby completing the present invention.

As the monoglyceride, there are a saturated fatty acid monoglyceride and an unsaturated fatty acid monoglyceride, and both have an antistatic effect. However, the unsaturated fatty acid monoglyceride can be added during storage of a saturated polyester resin processed product to which it is added. Oxidation may cause unpleasant odor or coloring, and saturated fatty acid monoglyceride is more preferred. However, the saturated fatty acid monoglyceride, after being kneaded, is quickly transferred to the resin surface, and exhibits an antistatic effect immediately after molding,
There is a drawback that the crystal form of the saturated fatty acid monoglyceride changes with the passage of time, and the antistatic effect decreases in accordance with the change.

The fatty acid mono- and diesters of diglycerin, which is a condensate of 2 mol of glycerin, have good compatibility with monoglyceride. These diglycerin fatty acid monoesters and diesters have amorphous physical properties, and crystallization of monoglycerides dissolved in those esters is suppressed. Also, since diglycerin fatty acid monoester has viscous physical properties, migration of diglycerin fatty acid monoester kneaded into the resin to the resin surface is slow, and diglycerin fatty acid diester has good compatibility with the resin. .

As described above, by using a mixture of monoglyceride and diglycerin fatty acid mono- and diesters, it is possible to obtain a good antistatic effect of monoglyceride and an initial antistatic property by suppressing crystal-type transition by diglycerin fatty acid ester, and a suitable surface. Since the transferability is obtained, the persistence is maintained, and the transparency of the saturated polyester resin is maintained without whitening due to the suppression of the crystallization of the diglycerin fatty acid ester amorphous and monoglyceride.

In a fatty acid ester of polyglycerin having a polymerization degree of glycerin of 3 mol or more, the number of hydroxyl groups in the polyglycerin molecule is large, and when the degree of esterification is low, the compatibility with the resin is inferior. Has a small antistatic effect and a low compatibility with monoglyceride, and its effect is inferior to that of diglycerin fatty acid ester.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below. Examples of the saturated polyester resin of the present invention include polyethylene terephthalate (PET), a copolymer of terephthalic acid with ethylene glycol and 1,4-cyclohexanedimethanol (PET-G), and a dibasic acid such as polybutylene terephthalate and a diol. Or a hydroxycarboxylic acid polymer such as polylactic acid. As a processing method of these saturated polyester resins, various molding methods such as injection molding, extrusion molding, and blow molding are possible, but in the present invention, the kind and processing method of those resins are not limited.

The fatty acids constituting the glycerin fatty acid monoester (monoglyceride) of the present invention include lauric acid, myristic acid, palmitic acid, stearic acid,
The main component is one or a mixture of two or more aliphatic fatty acids having 12 to 22 carbon atoms such as behenic acid, 12-hydroxystearic acid, oleic acid, linoleic acid, erucic acid and 12-hydroxyoleic acid. It is assumed that.

These monoglycerides can be esterified with the above fatty acids and glycerin, or beef tallow, lard, chicken fat,
Reaction obtained by transesterification of glycerin with one or a mixture of fish oil, soybean oil, corn oil, rapeseed oil, palm oil, sunflower oil, safflower oil, castor oil or hydrogenated oil thereof. Product (reacted monoglyceride) can be obtained by fractionation using methods such as molecular distillation, solvent fractionation, recrystallization, column chromatography, and supercritical gas extraction. In general, so-called distilled monoglyceride by molecular distillation is simple and easy to produce. It is appropriate in terms of price and the like.

As the fatty acid constituting the diglycerin fatty acid ester of the present invention, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, 12-hydroxystearic acid, oleic acid, Linoleic acid, erucic acid, 1
The main component is one or a mixture of two or more aliphatic fatty acids having 12 to 22 carbon atoms such as 2-hydroxyoleic acid.

As the raw material, fatty acids and fats and oils similar to those described above can be used. Diglycerin fatty acid ester is obtained by an esterification reaction between these fatty acids and diglycerin or a transesterification reaction between fats and oils and diglycerin,
If necessary, unreacted diglycerin or by-product glycerin or glycerin fatty acid ester is removed and purified by a method such as distillation under reduced pressure, molecular distillation, solvent fractionation, and column chromatography.

The ester of the diglycerin fatty acid ester in the present invention is preferably composed mainly of a monoester and a diester, and generally requires a reaction product having a diglycerin esterification ratio of 20 to 35% with the fatty acid. The unreacted diglycerin is removed by distillation according to the above. However, the reaction product can be purified and used as described above, and the esterification rate is not limited to these.

In the fatty acid ester of monoglyceride and diglycerin in the present invention, the fatty acid ester having less than 12 carbon atoms has high volatility upon heating,
The volatilization during the heat processing undesirably causes contamination of the manufacturing processing equipment or environmental pollution. Fatty acids having more than 22 carbon atoms are rare and expensive as natural raw materials and are not economical. Further, unsaturated fatty acids are oxidized during storage of the product, and may cause problems such as generation of an undesirable odor and discoloration of the product. Therefore, it is more preferable to use an ester of a saturated fatty acid.

In the present invention, the mixing ratio of monoglyceride and diglycerin fatty acid ester is 90 to 10:10 to 90, preferably 60 to 70:40 in weight ratio.
~ 30. When the proportion of monoglyceride exceeds 90% by weight, the durability of the antistatic effect becomes poor, and when the amount of diglycerin fatty acid ester exceeds 90% by weight, the initial antistatic effect becomes poor.

In the present invention, the antistatic composition comprising a mixture of monoglyceride and diglycerin fatty acid ester is added to the saturated polyester resin in an amount of 0.05 to 10 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the saturated polyester resin. 5 to 5 parts by weight. If the addition amount is less than 0.05 part by weight, the required antistatic effect cannot be obtained, and if it exceeds 10 parts by weight, bleeding increases, stickiness on the resin surface becomes remarkable, and transparency decreases.

The method of adding the antistatic agent composition of the present invention to a saturated polyester resin includes, for example, a method of directly mixing an antistatic agent composition and a saturated polyester resin powder and melt-mixing with an extruder; There is a method of preparing a master batch in which the composition is kneaded at a high concentration in a saturated polyester resin, and adding the required amount of the master batch at the time of forming the saturated polyester resin.However, in the present invention, those adding methods are limited. is not.

In the saturated polyester resin composition of the present invention, in addition to the antistatic agent, if necessary, known resin additives such as a phosphorus-based antioxidant, a sulfur-based antioxidant, a phenol-based antioxidant, A lubricant such as a fatty acid metal salt, or a nucleating agent, a coloring agent, and the like can be blended.

[0030]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to the following examples.

[Preparation of monoglyceride sample] The molar ratio of glycerin to glycerin was 1.0 (esterification ratio 3
3%) A small amount of alkali was added to a mixture with a considerable amount of fatty acid to perform an esterification reaction by a known method, and unreacted glycerin was removed by distillation under reduced pressure. Then, high-purity distilled monoglyceride was obtained by molecular distillation.

1. Monoglyceride having 12 carbon atoms (MG-
12): 98% purity of lauric acid: 92% purity of monoglyceride C16 / 18 monoglyceride (MG-16 /
18): Palmitic acid purity 45%. 2. Stearic acid purity 55%: monoglyceride purity 98% C22 monoglyceride (MG-22): behenic acid 90%, stearic acid 10%: monoglyceride purity 95%

[Preparation of Diglycerin Fatty Acid Ester Sample] The molar ratio of diglycerin to diglycerin was 1.0.
(Esterification rate 25%) or 1.4 (esterification rate 3
5%) A small amount of alkali was added to a mixture with a considerable amount of fatty acid, an esterification reaction was performed by a known method, and unreacted diglycerin was removed by molecular distillation to obtain a test diglycerin fatty acid ester.

1. Diglycerin fatty acid ester having 12 carbon atoms (DE-12): Lauric acid purity 98%: Monoester content; about 49%, diester content; about 3
9% 2. Diglycerin fatty acid ester having 16/18 carbon atoms (DE-16 / 18): palmitic acid purity 45%, stearic acid purity 55%: monoester content; about 33%, diester content; about 4
2% 3. Diglycerin fatty acid ester having 22 carbon atoms (DE-
22): 90% pure behenic acid, 10% pure stearic acid: monoester content; about 33%, diester content; about 4
2%

[Preparation of Triglycerin Fatty Acid Ester Sample] A glycerin was subjected to a heat polymerization reaction using a small amount of sodium hydroxide as a catalyst, and glycerin was 53% by weight, diglycerin was 35% by weight, triglycerin was 11% by weight, and tetraglycerin was 1% by weight. Was obtained.

The composition was subjected to vacuum distillation to remove glycerin by distillation, followed by molecular distillation to obtain an average degree of polymerization of 1% by weight of glycerin, 9% by weight of diglycerin, 80% by weight of triglycerin and 10% by weight of tetraglycerin. Molar polyglycerin (triglycerin) was obtained.

A small amount of alkali was added to this mixture of triglycerin and a fatty acid corresponding to a molar ratio of 1.5 to triglycerin (esterification ratio: 30%), and an esterification reaction was carried out by a known method. A fatty acid ester was obtained.

1. Triglycerin fatty acid ester having 16/18 carbon atoms (TE16 / 18): palmitic acid purity 45%, stearic acid purity 55%: monoester content; about 15%, diester content; about 3
7%, triester content; about 33%, tetraester or more; about 15%

[Test and Evaluation of Physical Properties] To 100 parts by weight of PET-G manufactured by Sumitomo Bakelite Co., was added a predetermined part by weight of an antistatic agent composition, and the mixture was injection-molded at 220 ° C. by an injection molding method and 100 × 100 A 2 mm plate was prepared. This plate was conditioned in a constant temperature and humidity chamber at 20 ° C. and 65% RH, and the surface specific resistance was measured according to the method of JIS K6911 using a super insulation meter SM-10E manufactured by Toa Denpasha. STATICONEST
JIS K1094 using METER S-5109
The half-life was measured according to the method described in Example 1, and the transparency of the plate was measured using a digital turbidimeter NDH-2D (manufactured by Nippon Denshoku Industries Co., Ltd.) (measuring unit # 90) according to the method of JIS K7105. ｝ Was measured.

[Test Antistatic Agent Composition and Amount Added] The composition of the antistatic agent composition used in the test (shown in parts by weight) is shown in Table 1.

[Results of Evaluation of Physical Properties] Table 2 shows the measurement results of the half-life (sec), and Table 3 shows the measurement results of the surface resistivity (Ω / □).
Table 4 shows the measurement results of turbidity and turbidity (%).

[0042]

[Table 1]

[0043]

[Table 2]

[0044]

[Table 3]

[0045]

[Table 4]

[0046]

EFFECTS OF THE INVENTION By using the antistatic agent of the present invention, a highly productive saturated polyester resin product having excellent antistatic effect without impairing transparency and having less stain on the surface of a molded product. Is obtained.

Claims (3)

[Claims] 1. A monoglyceride comprising 90 to 10% by weight of a monoglyceride having 12 to 22 carbon atoms of a constituent fatty acid and a diglycerin fatty acid ester having a carbon number of 12 to 22 of a constituent fatty acid.
An antistatic composition comprising 90% by weight of a mixture. 2. An antistatic composition according to claim 1, which is used for a saturated polyester resin composition. 3. A saturated polyester resin composition comprising the antistatic composition according to claim 1.