JP4757604B2 - Antistatic agent for polyester resin - Google Patents

Description

  The present invention relates to an antistatic agent for a polyester resin and a polyester resin composition containing the antistatic agent.

  Polyester resins, particularly amorphous polyester resins having no clear melting point, are used as materials for extrusion molding and various films and sheets. This amorphous polyester resin has better processability than ordinary polyester resins, and is suitable for extrusion molding and calendering.

As an antistatic agent for an amorphous polyester resin, a composite system of a polyglycerol fatty acid ester having an average degree of condensation of fatty acid monoglyceride and glycerol of 1.5 to 6 has been proposed (Patent Document 1).
JP 2003-138108 A

  When polyglycerin fatty acid ester, especially polyglycerin fatty acid ester having an average degree of condensation of glycerin of 4 or more, is added to the polyester resin, it is not well mixed with the polyester resin in the processing machine (large slippage), and this poor processability The present situation is that a polyester resin composition having sufficient antistatic performance has not been obtained.

  An object of the present invention is to provide an antistatic agent for a polyester resin that has good processability when added to a polyester resin and that can impart stable antistatic properties without impairing the transparency of the polyester resin, and It is providing the polyester resin composition excellent in workability, antistatic property, and transparency.

This invention provides the antistatic agent for polyester resins containing the following (a) component and (b) component, and the polyester resin composition containing this antistatic agent and a polyester resin.
(A) Component: 4-12 polyglycerol fatty acid ester having an average degree of condensation of glycerol (b) Component: calcium silicate

  The antistatic agent of the present invention can remarkably improve poor processability, which is a defect of polyglycerin fatty acid ester having an average degree of condensation of glycerin of 4 or more, and further imparts good antistatic property and transparency to the polyester resin. can do.

[Antistatic agent]
The antistatic agent of this invention contains the said (a) component and (b) component.

  The polyglycerin fatty acid ester having an average degree of condensation of glycerin (a) of 4 to 12 is a known method, for example, polyglycerin having an average degree of condensation of 4 to 12 and an excess aliphatic carboxylic acid, dibutyltin oxide, etc. This metal catalyst can be easily synthesized by heat dehydration at high temperature. Polyglycerol having an average degree of condensation of 4 to 12 can be synthesized by subjecting glycerol to a dehydration condensation reaction by a known method.

  The average degree of condensation of polyglycerol is determined by end group analysis. This end group analysis method is based on the relationship between the measured value of hydroxyl value (OHV) and the theoretical value, and the degree of condensation (n) and molecular weight (MW) of polyglycerin are determined by the following formula. The degree can be obtained [refer to “Polyglycerin ester, pages 33 to 34 (October 3, 1994, issued by Sakamoto Pharmaceutical Co., Ltd.)”].

MW = 74n + 18
OHV = 56110 (n + 2) / MW
From the viewpoint of obtaining good antistatic properties and transparency, the glycerin average condensation degree of the polyglycerol fatty acid ester is from 4 to 12, and preferably from 6 to 10. Moreover, 12-22 are preferable from a compatible viewpoint with resin, as for carbon number of the fatty acid which comprises polyglycerol fatty acid ester, 12-18 are still more preferable, and 16-18 are especially preferable.

  The average particle size of the component (b) calcium silicate is preferably 5 to 100 μm and more preferably 10 to 50 μm from the viewpoint of obtaining good processability. The oil absorption is preferably 200 mL / 100 g or more, more preferably 300 mL / 100 g or more, from the viewpoint of obtaining good processability. The upper limit of the oil absorption amount is not particularly specified, but is preferably 700 mL / 100 g or less. The shape of calcium silicate is preferably a gyrolite crystal type.

  Here, the average particle diameter and oil absorption of calcium silicate are values measured based on JIS K6220. As calcium silicate, for example, Fluorite R manufactured by Tokuyama Corporation can be used.

  The blending ratio of the component (a) and the component (b) in the antistatic agent of the present invention is (a) / (b) (weight ratio) = 40 / from the viewpoint of processability, antistatic property and transparency. 60-85 / 15 is preferable and 70 / 30-80 / 20 is still more preferable.

  The content of the component (a) in the antistatic agent of the present invention is preferably 50 to 85% by weight, more preferably 70 to 80% by weight, from the viewpoint of developing good antistatic properties and transparency. The content of the component (b) is preferably 15 to 50% by weight, and more preferably 20 to 30% by weight from the viewpoint of obtaining good processability.

  The antistatic agent of this invention may contain these manufacturing raw materials etc. other than (a) component and (b) component.

[Polyester resin]
In the present invention, the polyester resin is preferably an amorphous polyester resin. Here, the “amorphous polyester resin” refers to a polyester resin having a semi-crystallization time as defined below of 5 minutes or more.

<Semi-crystallization time>
First, 15 mg of a polyester resin is weighed in an aluminum pan, and heated to 300 ° C. at a rate of 300 ° C./min and melted using a differential scanning calorimetry (DSC) apparatus. Immediately cooled to 160 ° C. at a rate of 300 ° C./min, time measurement was started when the temperature reached 160 ° C., and the crystallization exothermic peak observed on the DSC curve while maintaining the set temperature at 160 ° C. The time to reach the top is defined as the half crystallization time.

  The DSC apparatus used here may be any apparatus as long as the temperature rising rate is 300 ° C./min or higher and the cooling rate using liquid nitrogen / liquid helium is 300 ° C./min or higher. For example, Perkin -Elmer DSC unit DSC7 or the like can be used.

  Polyethylene terephthalate, which is a crystalline polyester resin, has a half-crystallization time of about 50 seconds at 160 ° C. and cannot be calendered. In the present invention, the amorphous polyester resin is suitably a resin having a semi-crystallization time of 5 minutes or more, more preferably 10 minutes or more, and more preferably 12 from the viewpoint of enabling calendering. It is a polyester resin in which no crystallization peak is observed even after a lapse of time (hereinafter, the semi-crystallization time is infinite).

  Amorphous polyester resin has a lower processing temperature than the processing temperature of ordinary polyester resin is 270 to 280 ° C., and can be processed even under conditions of 200 ° C. or less, preferably 160 to 190 ° C. Good and can be calendered.

  Specific examples of the amorphous polyester resin include (A) terephthalic acid or a lower alkyl ester thereof (alkyl group having 1 to 3 carbon atoms such as dimethyl terephthalate) (hereinafter referred to as component (A)), (B) Ethylene glycol (hereinafter referred to as component (B)), and (C) dicarboxylic acid other than terephthalic acid or lower alkyl ester thereof or lower alkyl ester thereof (alkyl group having 1 to 3 carbon atoms) (hereinafter referred to as component (C)). Polyester resin obtained by copolymerization; (A) component, (B) component, and (D) polyester resin obtained by copolymerization of glycol components other than ethylene glycol (hereinafter referred to as (D) component); (A) component; Examples thereof include a polyester resin obtained by copolymerizing the component (B), the component (C), and the component (D).

  Examples of the component (C) include one or more selected from aromatic dicarboxylic acid, alicyclic dicarboxylic acid, aliphatic dicarboxylic acid, and lower alkyl esters thereof. As the aromatic dicarboxylic acid, isophthalic acid, Examples include phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, bis (4,4′-carboxyphenyl) methane, anthracene dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, and the like. Examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid and 4,4′-dicyclohexyldicarboxylic acid. Examples of the aliphatic dicarboxylic acid include adipic acid, sebacic acid, azelaic acid, and dimer acid. Among these (C) components, isophthalic acid and its lower alkyl ester are preferable.

  As the component (D), 1,4-cyclohexanedimethanol, propylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, decamethylene glycol, 4,4′-dicyclohexylhydroxymethane, Examples thereof include one or more selected from 4,4′-dicyclohexylhydroxypropane, bisphenol A ethylene oxide addition diol, polyethylene oxide glycol, polypropylene oxide glycol, and the like.

  The dicarboxylic acid component in the amorphous polyester resin is preferably 60 mol% or more of the aromatic dicarboxylic acid component, and more preferably 60 mol% or more of the component (A). The glycol component is preferably 60 mol% or more of the component (B).

  The glass transition temperature of the amorphous polyester resin is preferably 50 to 85 ° C, and more preferably 60 to 85 ° C.

  As the amorphous polyester resin, TSUNAMI (also known as cadence) GS1, GS2, GS3, GS4, etc. manufactured by Eastman Chemical Co., Ltd. can be used.

[Polyester resin composition]
The polyester resin composition of the present invention contains the antistatic agent of the present invention as described above and a polyester resin.

  60-99 weight% is preferable and, as for content of the polyester resin in the polyester resin composition of this invention, 70-99 weight% is still more preferable. The content of the antistatic agent of the present invention is preferably 0.05 to 5 parts by weight, more preferably 1 to 5 parts by weight, based on 100 parts by weight of the polyester resin, from the viewpoint of antistatic properties, transparency and processability. .

  In addition to the antistatic agent, the composition of the present invention includes rubber, elastomer, resin, lubricant, plasticizer, antifogging agent, light stabilizer, ultraviolet absorber, pigment, inorganic filler, antifungal agent, antibacterial agent, A foaming agent, a flame retardant, etc. can be contained in the range which does not prevent achievement of the objective of this invention.

  Since the composition of the present invention has good processability and can be processed at a low temperature such as 160 to 190 ° C., extrusion and calendering are also possible. The composition of the present invention can be formed into an extruded product, a film or a sheet and used for various applications.

Production Example Using a 20 L supermixer with a rotation of 600 r / min and a tube wall heated to 90 ° C., 1 kg of Fluorite R (made by Tokuyama Corp., average particle size 25 μm, oil absorption 400 mL / 100 g), which is calcium silicate powder On the other hand, the liquefied polyglycerin fatty acid esters shown in the following (a-1) to (a-3) are added over 2 minutes so as to have the ratio shown in Table 1, and are supported to charge the present invention. Inhibitors 1-4 were obtained.
(A-1): Decaglycerin C ₁₈ fatty acid ester Sunsoft Q-18S manufactured by Taiyo Kagaku Co., Ltd., obtained by esterifying decaglycerin having a glycerin average condensation degree of 10 with stearic acid.
(A-2): Hexaglycerin C ₁₈ fatty acid ester Sunsoft Q-18F manufactured by Taiyo Kagaku Co., Ltd., obtained by esterifying hexaglycerin having a glycerin average condensation degree of 6 with stearic acid.
(A-3): decaglycerol C ₁₂ fatty acid esters of glycerin average degree of condensation is obtained by esterification of decaglycerol 10 with lauric acid, Taiyo Kagaku Co., Ltd. Sunsoft Q-12S.

  Moreover, as a comparative antistatic agent, the component (b) was not blended, and only the components (a-1) to (a-2) were used. These are also summarized in Table 1.

Examples 1-2
Eastman Chemical's Cadence GS1 is used as the polyester resin, antistatic agents 1 and 2 are used as the antistatic agent, glycerin monostearate (hereinafter referred to as “lubricant 1”) is used as the lubricant, and the antistatic agent is added to 100 parts by weight of the polyester resin. And the quantity shown in Table 2 was added, and it mixed using the Henschel mixer, and obtained the formulation. The resulting blend was kneaded using a 40 mm twin screw extruder set at a cylinder temperature of 190 ° C. and a die temperature of 180 ° C., and extruded to be pelletized. The obtained pellets were put into a 40 mm single screw extruder equipped with a mold having a width of 50 mm and a thickness of 1 mm to obtain a tape-like extruded product. The extruder temperature conditions were a cylinder temperature of 210 ° C. and a mold temperature of 170 ° C.

  The pellet processability, antistatic property and transparency at this time were evaluated by the following methods. The results are shown in Table 2.

<Pellet workability>
The situation when pelletizing using a twin screw extruder was evaluated according to the following criteria.
◯: Continuous pelletization without problems.
X: Pelletization was not possible.

<Antistatic property>
The surface resistivity of the molded product was measured with Hiresta manufactured by Mitsubishi Chemical Corporation at a humidity of 50% and an applied voltage of 500 V in accordance with ASTM D257.
1 × 10 ⁸ Ω / sq. 1 × 10 ¹² Ω / sq. Less than a good range, 1 × 10 ¹² Ω / sq. 1 × 10 ¹³ Ω / sq. Less than a slightly good range, 1 × 10 ¹³ Ω / sq. The above is defined as a defective range.

<Transparency>
Using the molded product, transparency was evaluated by measuring the haze value of the sheet with a haze meter based on the method of JIS K7105. Smaller numbers indicate better transparency.

  In addition, about Example 1 and 2, the discharge amount (kg / hour) at the time of obtaining a tape-like extrusion-molded product using a single screw extruder is measured, and the situation at the time of further extrusion molding into a tape (extrusion) Although tape formability was evaluated, continuous tape formation was possible without problems. Moreover, although the external appearance of the obtained tape molded product was evaluated visually, all were favorable.

Example 3
Use Eastman Chemical's Cadence GS1 as the polyester resin, antistatic agent 3 as the antistatic agent, and lubricant 1 as the lubricant. Add 100% by weight of the antistatic agent and lubricant to 100 parts by weight of the polyester resin. The mixture was mixed using a Henschel mixer. The obtained blend was directly put into a 40 mm single screw extruder equipped with a 50 mm wide and 1 mm thick mold without pelletization to obtain a tape-like extruded product. The extruder temperature conditions were a cylinder temperature of 210 ° C. and a mold temperature of 170 ° C.

The antistatic property and transparency at this time were evaluated in the same manner as in Example 1. The results are shown in Table 2.
In addition, about Example 3, although extrusion tape moldability was evaluated similarly to Example 1, it was possible to tape-form continuously without a problem, and the appearance of the obtained tape molded product was evaluated visually. there were.

Comparative Examples 1-2
Table 2 shows the comparative antistatic agent and lubricant for 100 parts by weight of the polyester resin, using Cadence GS1 manufactured by Eastman Chemical Co. as the polyester resin, comparative antistatic agent 1 or 2 as the antistatic agent, and lubricant 1 as the lubricant. The indicated amount was added and mixed using a Henschel mixer to obtain a blend. Attempts were made to pelletize the resulting blend, but when the blend was mixed at a low temperature, the dispersion of the blend was not sufficient and kneading was not stable using a twin screw extruder, and pelletization was not possible. . When the blend was mixed at a temperature of 60 ° C., the dispersion proceeded, but the blend was hardened, and the material could not be fed at the feed port of the twin screw extruder, and could not be pelletized.

  About these comparative examples 1 and 2, since pelletization cannot be performed, extrusion tape moldability and the external appearance of the obtained tape molded product could not be evaluated.

Example 4
Use Eastman Chemical's Cadence GS1 as the polyester resin, antistatic agent 1 as the antistatic agent, and lubricant 1 as the lubricant. Add 100 parts by weight of the antistatic agent and lubricant to 100 parts by weight of the polyester resin. The mixture was obtained by mixing using a Henschel mixer. The resulting blend was kneaded using a 40 mm twin screw extruder set at a cylinder temperature of 190 ° C. and a die temperature of 180 ° C., and extruded to be pelletized. The obtained pellets were kneaded for 3 to 7 minutes with a 6 inch roll at 160 ° C. to obtain a 0.5 mm thick calendar sheet molded product as it was, and this calendar sheet molded product was further subjected to metal press with a 160 ° C. press molding machine. The plate was pressed to obtain a 1 mm thick sheet molded product.

  The pellet processability, antistatic properties and transparency at this time were evaluated in the same manner as in Example 1. These results are shown in Table 3.

  In addition, as a result of evaluating the situation (press moldability) when a 1 mm thick sheet molded product was obtained using a press machine, a smooth molded product having good peelability from the metal press plate was obtained. Moreover, although the external appearance of the sheet molded product obtained similarly to Example 1 was evaluated, it was favorable.

Examples 5-6
The polyester resin is Cadence GS1 manufactured by Eastman Chemical Co., the antistatic agents 3 and 4 are used as the antistatic agent, and the lubricant 1 or pentaerythritol adipic acid stearate (hereinafter referred to as the lubricant 2) is used as the lubricant. The amount of antistatic agent and lubricant shown in Table 3 was added to the part and mixed using a Henschel mixer to obtain a blend. The resulting blend was kneaded using a 40 mm twin screw extruder set at a cylinder temperature of 190 ° C. and a die temperature of 180 ° C., and extruded to be pelletized. The obtained pellets were kneaded for 3 to 7 minutes with a 6-inch roll at 160 ° C. to obtain a 0.5 mm-thick calendar sheet molded product as it was.

  The pellet processability, antistatic properties and transparency at this time were evaluated in the same manner as in Example 1. These results are shown in Table 3.

  In addition, as a result of evaluating the situation (calendar sheet formability) when forming into a film using a 6-inch roll, the film could be formed in a melt kneading time of less than 5 minutes. Moreover, although the external appearance of the sheet molded product obtained similarly to Example 1 was evaluated, it was favorable.

Comparative Example 3
A calendar sheet molded article was obtained in the same manner as in Example 5 except that no antistatic agent was added. The pellet processability, antistatic property and transparency at this time were evaluated in the same manner as in Example 5. These results are shown in Table 3.
The calender sheet formability and the appearance of the obtained sheet molded product were evaluated and were good as in Examples 5 and 6.

Claims (6)

The antistatic agent for polyester resins containing the following (a) component and (b) component.
(A) Component: Polyglycerol fatty acid ester having an average degree of condensation of glycerol of 4 to 12 (b) Component: Calcium silicate   The antistatic agent according to claim 1, wherein the constituent fatty acid (a) has 12 to 22 carbon atoms.   The antistatic agent according to claim 1 or 2, wherein the component (b) has an oil absorption of 200 mL / 100 g or more.   The polyester resin composition containing a polyester resin and the antistatic agent in any one of Claims 1-3.   The polyester resin composition according to claim 4, wherein the content of the antistatic agent is 0.05 to 5 parts by weight with respect to 100 parts by weight of the polyester resin. The polyester resin composition according to claim 4 or 5, wherein the polyester resin is an amorphous polyester resin.