JP2005336383A - Amorphous polyester resin composition and molded article by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an amorphous polyester resin composition having a small change with time in its flexibility, being transparent, and excellent in flexibility and bleeding resistance under a low temperature environment at or lower than a room temperature (23°C), and a molded article by using the same. <P>SOLUTION: This amorphous polyester resin composition is provided by containing an amorphous polyester resin obtained by performing the condensation reaction by using terephthalic acid and ethylene glycol as main components and further using a dicarboxylic acid and/or glycol for imparting the amorphous property, and a copolymer obtained by performing the reaction of an amorphous polyester with a polyoxyalkylene and having 500-2,000 number-average molecular weight. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an amorphous polyester resin composition and a molded product using the same. More specifically, the present invention relates to an amorphous polyester resin composition that is transparent, has little change in flexibility with time, and is excellent in low-temperature flexibility and bleed resistance, and a molded product using the same.

In general, a vinyl halide resin represented by a vinyl chloride resin or a copolymer thereof is itself a hard and brittle one. Therefore, an appropriate amount of an appropriate plasticizer and other additives as necessary are added thereto. As a soft vinyl halide resin composition, it is used for various molded articles.
Among them, in particular, the soft vinyl chloride resin-based composition can easily adjust the softness by changing the addition amount of the plasticizer, and can obtain a molded product having flexibility according to the use. For example, it has been used in a wide range of fields such as sheets, floor materials, wall materials, dolls, toys, gloves, boots, hoses, tubes, tapes, steel plate coating materials, and automobile interior materials.

On the other hand, vinyl chloride resin is inferior in weather resistance and has a large color change, and since hydrogen chloride gas and dioxin are generated during incineration, there are concerns about adverse effects on the natural environment. There has been a strong demand for conversion from resins to non-halogen resins.
Furthermore, some plasticizers conventionally used in halogen-based resins may be a substance that disturbs the endocrine action and may affect the reproduction and development of wildlife and humans. There has been a demand for the development of a non-halogen resin to replace the resin.

  Modified amorphous polyester having a molecular structure in which a part of structural units derived from ethylene glycol in polyethylene terephthalate (hereinafter referred to as PET) is substituted with cyclohexanedimethanol units as an alternative to soft vinyl chloride resin Attempts have been made to use PET-based resins such as PET (hereinafter referred to as PET-G), but when plasticizer is blended for softening and there is flexibility at room temperature, crystallization gradually As the process progresses and the transparency is lost and the composition becomes hard, the use thereof is limited particularly in fields where transparency and flexibility are required, for example, for applications such as sheets and packaging materials.

Various proposals have been made to solve the above problems.
As a soft polyester resin composition excellent in flexibility that can be substituted for a soft vinyl chloride resin composition, an amorphous random cocondensation polyester in which 50% or more of the diol units constituting the cocondensation polyester are composed of ethylene glycol is plasticized. A soft polyester composition using a compound having a polyalkylene glycol structure as an agent (see, for example, Patent Document 1) has been proposed.
However, such a soft polyester composition has insufficient compatibility between the plasticizer and the co-condensation polyester. When the plasticizer is added in an amount necessary for obtaining the soft performance, the plastic polyester composition can be obtained from the soft polyester composition. Separation (bleeding) of the agent occurred and there was a problem in practical use.

In addition, as an amorphous polyester resin that can be calendered and has good elongation at low temperatures, a resin for a sheet obtained by adding a polymer having a glycol as a structural unit to an amorphous polyester resin, or a fatty acid ester of polyether or glycerin ( For example, see Patent Document 2).
However, a resin for a sheet containing such a glycol-based polymer or a plasticizer such as a polyether or a fatty acid ester of glycerin has good flexibility in a temperature range of 23 to 40 ° C. higher than room temperature (23 ° C.). However, under low temperature conditions below room temperature, the flexibility is significantly reduced and the practicality is poor. When the amount of the plasticizer used is increased to improve this, the plasticizer is separated from the sheet resin. (Bleed).

JP 2001-151996 A (page 2 claims to page 5 right column paragraph 0014) Japanese Patent Laid-Open No. 2002-294043 (claims from page 2 claims to page 3, left column, paragraph 0013)

  As described above, various soft polyester resin compositions that have been proposed as alternatives to the conventional soft vinyl chloride resin composition may change in flexibility over time, or may be, for example, room temperature (23 ° C.) or lower. However, the flexibility and bleed resistance in a low temperature environment were not excellent.

  An object of the present invention is an amorphous polyester resin composition which is small in change in flexibility over time, is transparent, and has excellent flexibility and bleed resistance in a low temperature environment of, for example, room temperature (23 ° C.) or less, and the use thereof It is to provide a molded product.

  As a result of intensive studies to solve the above problems, the present inventors have used terephthalic acid and ethylene glycol as the main components, and further carried out a condensation reaction using dicarboxylic acid and / or glycol that imparts amorphous properties. By blending the amorphous polyester resin (A) obtained and the copolymer (C) obtained by reacting the amorphous polyester (B) with the polyoxyalkylene compound, it is transparent and has low temperature flexibility and It has been found that an amorphous polyester resin composition having excellent bleed resistance can be obtained, and the present invention has been completed.

  That is, the present invention uses an amorphous polyester resin (A) obtained by a condensation reaction using terephthalic acid and ethylene glycol as main components and further using a dicarboxylic acid and / or glycol imparting amorphous properties, An amorphous polyester resin composition comprising a copolymer (C) having a number average molecular weight of 500 to 2,000 obtained by reacting a crystalline polyester (B) with a polyoxyalkylene compound is provided. To do.

  Moreover, this invention provides the molded article obtained using the said amorphous polyester resin composition.

  According to the present invention, it is possible to obtain an amorphous polyester resin composition that is transparent and has a small change in flexibility with time and is excellent in low-temperature flexibility and bleed resistance. Molded articles obtained using the amorphous polyester resin composition include, for example, sheets, flooring, wall materials, dolls, toys, gloves, boots, hoses, tubes, tapes, steel sheet coating materials, automobiles, and the like. It can be used in a wide range as interior materials, containers for foods and beverages, pharmaceuticals, packaging materials, cases for electronic devices, office supplies, container lids, and ID card sheets.

  The amorphous polyester resin composition of the present invention is an amorphous polyester resin obtained by a condensation reaction using terephthalic acid and ethylene glycol as main components and further using a dicarboxylic acid and / or glycol that imparts amorphous properties. (A) and the copolymer (C) which has a number average molecular weight of 500-2,000 obtained by making an amorphous polyester (B) and a polyoxyalkylene compound react. Here, the copolymer (C) acts as a plasticizer, and expresses the effect of imparting flexibility to the resulting amorphous polyester resin composition, particularly in a low temperature environment.

  The amorphous polyester resin referred to in the present invention is a polyester resin in which no clear crystallization peak is observed by the differential scanning calorimetry (DSC) method of JIS K 7121. The processing temperature of a normal polyester resin is, for example, 270 to 280. The processing temperature is lower than that of ℃, usually 200 ℃ or less, preferably 160-190 ℃, so that the workability is good. Besides extrusion molding and injection molding, calendar molding is also possible. Is possible.

  The amorphous polyester resin (A) used in the amorphous polyester resin composition of the present invention comprises terephthalic acid and ethylene glycol as main components, and further uses dicarboxylic acid and / or glycol as components for imparting amorphousness. It is a polymer obtained by a condensation reaction.

  Of the raw materials used for producing the amorphous polyester resin (A), 60 mol% or more of the total amount of dicarboxylic acid is preferably terephthalic acid, and 60 mol% or more of the total amount of glycol is ethylene glycol. Preferably there is.

  Examples of the dicarboxylic acid imparting the amorphous property include aromatic dicarboxylic acids such as orthophthalic acid and isophthalic acid, aliphatic dicarboxylic acids such as adipic acid and sebacic acid, or 1,4-cyclohexanedicarboxylic acid. And alicyclic dicarboxylic acids such as Examples of the glycol imparting amorphous properties include 1,4-cyclohexanedimethanol, propylene glycol, neopentyl glycol, polyethylene oxide glycol, and polypropylene oxide glycol. These compounds may be used alone or as a mixture of two or more.

  Among these, among the raw materials used in producing the amorphous polyester resin (A), the dicarboxylic acid is terephthalic acid, 60 to 80 mol% of the total amount of glycol is ethylene glycol, and 20 to 40 mol. % Is 1,4-cyclohexanedimethanol and preferably has an intrinsic viscosity IV of 0.65 to 0.85.

Next, a copolymer having a number average molecular weight of 500 to 2,000, obtained by reacting the amorphous polyester (B) with a polyoxyalkylene compound, which is used in the amorphous polyester resin composition of the present invention. (C) will be described.
This acts as a plasticizer and exhibits an effect of imparting flexibility to the amorphous polyester resin composition obtained, particularly in a low temperature environment.

Such a copolymer (C) can generally be easily produced by subjecting an amorphous polyester resin and a polyoxyalkylene compound to a transesterification reaction using a known esterification reaction catalyst.
For example, a predetermined raw material containing 20 to 80% by weight of a polyoxyalkylene compound is heated in a nitrogen stream and preferably in the range of 130 to 250 ° C., and the transesterification is performed for 2 to 12 hours. If necessary, the reaction can be carried out under a reduced pressure condition of 0.1 kPa or less to obtain a copolymer having a number average molecular weight of 500 to 2,000.
The content of the structural unit derived from the polyoxyalkylene compound in the copolymer (C) to be obtained is preferably 20 to 80% by weight.

Among the raw materials used when producing the copolymer (C), the amorphous polyester (B) is mainly composed of terephthalic acid and ethylene glycol, and further, the amorphous polyester as a component for imparting amorphous properties. It can be obtained by a condensation reaction using the same dicarboxylic acid and / or glycol as exemplified in the description of the resin (A).
The composition of the raw material used when producing the copolymer (C) may be the same as or different from the composition of the amorphous polyester resin (A) used, but is preferably the same.

Examples of polyoxyalkylene compounds include ethylene oxide such as phenol, benzyl alcohol, alkylphenol, and aliphatic alcohol, ether compounds of propylene oxide adducts, ethylene oxides such as fatty acids and aromatic carboxylic acids, and ether ester compounds of propylene oxide adducts. Can be given.
The number of moles of ethylene oxide and propylene oxide added is preferably in the range of 1 to 20 moles, more preferably in the range of 4 to 8 moles, with respect to 1 mole of alcohol or acid. These polyoxyalkylene compounds may be used alone or in combination of two or more.

  Further, the esterification reaction catalyst is not particularly limited, but for example, an acid catalyst such as paratoluenesulfonic acid and phosphoric acid, or tetraisopropyl titanate, tetrabutyl titanate, dibutyltin oxide, dioctyltin oxide, zinc chloride, etc. A metal catalyst etc. are mentioned.

The ratio of the content of the amorphous polyester resin (A) and the copolymer (C) in the amorphous polyester resin composition of the present invention is preferably based on 100 parts by weight of the amorphous polyester resin (A). Is in the range of 5 to 80 parts by weight of the copolymer (C), more preferably in the range of 10 to 60 parts by weight of the copolymer (C).
If the content ratio of both is in such a range, it is transparent and has almost no change in flexibility over time, and has an excellent plasticizing effect by the copolymer (C), and an amorphous polyester resin composition and Even when a molded product obtained using the same is stored for a long period of time, the separation (bleeding) of the copolymer (C) as a plasticizer on the surface of the amorphous poly-ester resin composition is reduced as much as possible.

Next, the manufacturing method of the amorphous polyester resin composition used by this invention is demonstrated.
The amorphous polyester resin composition of the present invention includes, for example, an amorphous polyester resin (A), and a copolymer (C) obtained by reacting an amorphous polyester (B) with a polyoxyalkylene compound, Further, various resins and additives can be blended in predetermined amounts as necessary, and can be obtained by, for example, using a known mixing means such as a ribbon blender, a super mixer, a Henschel mixer, and the like.

  The amorphous polyester resin composition of the present invention can be processed by employing known molding methods such as press molding, extrusion molding, injection molding, calendar molding, etc., depending on the purpose of use. It is preferable to preliminarily pelletize the amorphous polyester resin composition after melt-kneading using a known method such as Banbury, an extruder, or a two-roll.

  In the amorphous polyester resin composition of the present invention, if necessary, for example, phthalic acid esters, adipic acid esters, sebacic acid esters, trimellitic acid esters can be used without departing from the object of the present invention. It is used as a well-known and commonly used plasticizer such as pyromellitic acid esters, epoxy esters such as epoxidized soybean oil, phosphoric acid esters, polyesters, cyclohexane carboxylic acid esters, cyclohexene carboxylic acid esters, etc. Or additives such as lubricants, antioxidants, ultraviolet absorbers and fillers may be used in combination.

  Examples of the lubricant include ester waxes such as montanic acid wax, amides such as ethylene bis (stearamide), hydrocarbon waxes such as polyethylene wax, fatty acids such as stearic acid, and fatty acid esters such as glycerol ester. , Metal soaps such as calcium stearate, and various lubricants such as phosphate esters.

  Examples of the antioxidant include phenolic antioxidants such as 2,6-di-t-butyl-p-cresol, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl). Examples include hindered phenolic antioxidants such as propionate, thioether antioxidants such as dilauryl thiodipropionate, and phosphoric acid antioxidants such as trisnonylphenol phosphite.

  Examples of the ultraviolet absorber include salicylate compounds such as phenyl salicylate, benzophenone compounds such as 2-hydroxy-4-methoxybenzophenone, 2- (2′-hydroxy-5′-t-butylphenyl) benzotriazole, and the like. Benzotriazole compounds, 2-ethylhexyl-2-cyano-3,3′-diphenyl acrylate and other cyanoacrylate compounds, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and other hindered amine compounds Etc.

  Examples of the filler include calcium carbonate, clay, talc, silica, aluminum hydroxide, magnesium oxide, magnesium carbonate, magnesium silicate, and calcium silicate.

  The amorphous polyester resin composition of the present invention has a small change in flexibility over time and is excellent in low temperature flexibility and bleed resistance under low temperature conditions around 0 ° C., for example, a sheet, a flooring material, a wall material, Dolls, toys, gloves, boots, hoses, tubes, tapes, steel plate coating materials, automotive interior materials, food and beverage products, containers for pharmaceuticals, packaging materials, electronic equipment, office supplies, etc., molded It is extremely useful in a wide range as a molded product such as a container lid or an ID card sheet.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention more concretely, this invention is not limited to these Examples.
In the text, “part” and “%” are based on weight unless otherwise specified.
Various characteristics were measured by the methods described in the text.

(Synthesis Example 1)
Amorphous polyester resin “Tsunami GS2; manufactured by Eastman Chemical Co.” (glycol-modified PET, which is an amorphous copolyester modified by substituting a part of the ethylene glycol component, which is a raw material of PET, with cyclohexanedimethanol. ) 1.00 kg and 1.00 kg of polyoxyethylene phenyl ether (BLAUNON PH-4: manufactured by Aoki Oil & Fat Co., Ltd.), stirred and melted at 230 ° C., and then subjected to transesterification for 3 hours, weight average 1.8 kg of copolymer C1 having a molecular weight of 1,600 and a number average molecular weight of 1,100 was obtained.
The molecular weight was measured by comparison with a polystyrene standard sample using a gel permeation chromatography measuring device (hereinafter referred to as GPC, HLC-8020 manufactured by Tosoh Corporation, column temperature 40 ° C., tetrahydrofuran solvent).

(Synthesis Example 2)
1.40 kg of amorphous polyester resin “Tsunami GS2” (trademark; manufactured by Eastman Chemical Co., Ltd.) and 0.60 kg of polyoxyethylene benzyl ether (BLAUNON BA-5: manufactured by Aoki Oil & Fat Co., Ltd.) After stirring and melting at 230 ° C., a transesterification reaction was performed for 3 hours to obtain 1.8 kg of copolymer C2 having a weight average molecular weight of 1,500 and a number average molecular weight of 1,300.

[Example 1] to [Example 3]
“Tsunami GS2” (trademark; manufactured by Eastman Chemical Co., Ltd.) as an amorphous polyester resin, montanic acid wax as a lubricant, the copolymer C1, and the copolymer C2 are mixed according to the blending amounts shown in Table 1 and stirred. Thus, an amorphous polyester resin composition was prepared.
Each amorphous polyester resin composition was kneaded for 10 minutes with a 6-inch roll set at 150 ° C., and then molded into a sheet having a thickness of 1 mm using a 160 ° C. press molding machine.
The obtained sheet was evaluated for flexibility, change with time, transparency, and surface condition by the following methods. The evaluation results are shown in Table 2.

[Comparative Example 1] to [Comparative Example 3]
Using the composition prepared according to the blending amount shown in Table 1, a sheet was prepared in the same procedure as in the above example, and the obtained sheet was subjected to the following methods for flexibility, change with time, transparency, and surface condition. Evaluated. The evaluation results are shown in Table 2.

[Flexibility evaluation method]
In accordance with the tensile test of JIS K 7113, the sheet was punched with a No. 2 dumbbell, and a tensile test was performed at a measurement temperature of 0 ° C. and 23 ° C. at a tensile speed of 200 mm / min. ) And JIS K 6253 measured in accordance with JIS K 6253. The lower the 100% modulus and hardness, the better the flexibility.

[Method for evaluating changes over time]
The ratio of 100% modulus immediately after sheet preparation to 100% modulus after standing at room temperature (23 ° C.) for 1 month was determined by the following formula and evaluated. The closer the 100% modulus ratio is to 1, the smaller the change with time, and the better.
100% modulus ratio = (100% modulus after 1 month) / (100% modulus immediately after)

[Transparency evaluation method]
Evaluation was made by visual observation. The evaluation results were shown according to the following criteria.
○: Good transparency △: Somewhat poor transparency ×: Poor transparency

[Surface condition (existence of bleed)]
The sheet (length 100 mm × width 100 mm × thickness 1 mm) was allowed to stand in a thermostatic chamber at 50 ° C. for 1 week, and then the state of the plasticizer bleed on the surface was visually observed and evaluated according to the following criteria.
○: Good bleed resistance.
Δ: Slightly poor bleed resistance.
X: Bleed resistance failure.

  Specific contents of the copolymers C1 and C2 and plasticizers D, E, and F shown in Table 1 are as follows.

PET-G: Tsunami GS2 [1,4-cyclohexanedimethanol-modified PET, trademark; manufactured by Eastman Chemical Co., Ltd.]
Lubricant: Montanic acid wax copolymer C1: PET-G / polyoxyethylene phenyl ether copolymer Copolymer C2: PET-G / polyoxyethylene benzyl ether copolymer Plasticizer D: Polyoxyethylene phenyl ether (BLAUNON) PH-4: Aoki Yushi Kogyo Co., Ltd.)
Plasticizer E: PEG300 octyl acid diester Plasticizer F: Glycerin diacetomonolaurate

Claims (6)

Amorphous polyester resin (A) and amorphous polyester (B) obtained by a condensation reaction using terephthalic acid and ethylene glycol as main components and further using a dicarboxylic acid and / or glycol imparting amorphous properties An amorphous polyester resin composition comprising a copolymer (C) having a number average molecular weight of 500 to 2,000, which is obtained by reacting a polyoxyalkylene compound. The amorphous polyester resin composition according to claim 1, wherein the amorphous polyester (B) is the amorphous polyester resin (A). The amorphous polyester resin composition according to claim 1, wherein the content of the structural unit derived from the polyoxyalkylene compound in the copolymer (C) is 20 to 80% by weight. The amorphous polyester resin composition of Claim 1 which contains the said copolymer (C) in 5-80 weight part with respect to 100 weight part of said amorphous polyester resin (A). The amorphous polyester resin composition according to claim 1, wherein the polyoxyalkylene compound is polyoxyethylene phenyl ether or polyoxyethylene benzyl ether. A molded product obtained by molding the amorphous polyester resin composition according to claim 1.