JP2012184346A - Polyester composition and polyester molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester composition having antibacterial activity from the composition stage without performing post-processing, excellent in melt moldability and utilizable to molded products and fibers.SOLUTION: This polyester composition includes at least one aluminum compound selected from the group consisting of inorganic compounds containing a metal aluminum atom and organoaluminum compounds within a range satisfying the following numerical expression: 0.01 wt.%≤Al≤10.0 wt.% (wherein Al represents mass% concentration of aluminum in the polyester composition).

Description

  The present invention relates to a polyester composition. More specifically, the present invention relates to a polyester composition having antibacterial properties without performing post-processing, and relates to polyester molded products and polyester fibers that are excellent in melt moldability and can be used for various industrial products.

  Polyesters, especially polyethylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate and polytetramethylene terephthalate are widely used in fibers, films or other moldings because of their excellent mechanical, physical and chemical performance. Yes. Linear saturated polyesters (for example, polyethylene terephthalate) mainly composed of aromatic dicarboxylic acid and alkylene glycol are used in a wide range of applications due to their excellent physical properties and chemical properties.

The purpose of polyester fiber is to impart antibacterial properties to carpets, mats, sheets, curtains, and futons for the purpose of preventing pathogens in hospitals and other sanitary fields, or to deodorize socks and tights. Consideration of imparting antibacterial properties is ongoing.
Currently, the antibacterial treatment methods currently being studied are post-processing of organic antibacterial agents typified by quaternary ammonium salts, chitosan, hinokitiol, polyphenol, and inorganic antibacterial agents typified by silver. For example, a method of adhering to the surface of a polymer material such as polyester fiber, or a method of incorporating an antibacterial agent into a polymer resin such as polyester by kneading.

  The method of imparting antibacterial properties by post-processing has a problem that it adversely affects other post-processing treatments such as water-repellent processing and antistatic processing, or the anti-bacterial properties are lost by other post-processing treatments. Therefore, it has been desired to develop a polyester fiber having antibacterial properties at the fiber yarn stage regardless of post-processing.

  An example of a method for producing polyester that does not require post-processing is a method in which an antibacterial agent is kneaded with a polyester resin. Silver compounds, zinc compounds, tin compounds, lead compounds, copper compounds, etc. have been developed as antibacterial agents to be incorporated into such resins, but the metals of these inorganic antibacterial agents are harmful. It is necessary to include a large amount of heavy metal in the resin, which is not sufficient in terms of safety to the human body and environmental load (see, for example, Patent Document 1).

JP 2000-212419 A

  An object of the present invention is to obtain a polyester resin having antibacterial properties from the composition stage, and to provide an industrially useful polyester molded article by molding this polyester resin.

As a result of intensive studies in view of the above-described prior art, the present inventors have completed the present invention. That is, the present invention is characterized in that the polyester resin contains at least one aluminum compound selected from the group consisting of an inorganic compound containing a metal aluminum atom and an organic aluminum compound in a range satisfying the following mathematical formula (1). This is a polyester composition, which can solve the above problems.
0.01 wt% ≦ Al ≦ 10.0 wt% (1)
[In the above formula, Al represents the mass percent concentration of aluminum with respect to the polyester composition. ]

  According to the present invention, a polyester composition having antibacterial properties can be obtained at the polyester composition stage, and various industrially useful antibacterial polyester molded articles can be obtained without performing post-processing.

<About polyester>
The present invention will be described in detail below. As the polyester polymer constituting the polyester composition of the present invention, a general-purpose polyester polymer is used. Among them, the main repeating unit of the polyester is selected from the group consisting of ethylene terephthalate, ethylene-2,6-naphthalate, trimethylene terephthalate, trimethylene-2,6-naphthalate, butylene terephthalate and butylene-2,6-naphthalate. It is preferable. In view of the excellent physical properties and suitable for mass production, it is preferable to use polyethylene terephthalate characterized in that the main acid component constituting the polyester resin is terephthalic acid and the diol component is ethylene glycol. As a main repeating unit of polyester, it is preferable that 80 mol% or more of the repeating unit is contained with respect to all dicarboxylic acid components constituting the polyester. Particularly preferred is a polyester containing 90 mol% or more. Moreover, if it is a small amount in the polyester polymer, it may be a copolymer containing an appropriate third component.

  For example, as the polyester polymer constituting the polyester composition of the present invention, terephthalic acid, naphthalene-2,6-dicarboxylic acid or a functional derivative thereof can be polymerized in the presence of a catalyst under appropriate reaction conditions. it can. In addition, a copolymerized polyester is synthesized by adding one or more appropriate third components before the completion of polymerization of the polyester. Suitable third components include: (a) compounds having two ester-forming functional groups, for example, aliphatic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid; cyclopropanedicarboxylic acid, Cycloaliphatic dicarboxylic acids such as cyclobutanedicarboxylic acid and hexahydroterephthalic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, naphthalene-2,7-dicarboxylic acid, diphenyldicarboxylic acid; diphenyl ether dicarboxylic acid, diphenylsulfone dicarboxylic acid, Carboxylic acids such as diphenoxyethanedicarboxylic acid and sodium 3,5-dicarboxybenzenesulfonate; oxycarboxylic acids such as glycolic acid, p-oxybenzoic acid and p-oxyethoxybenzoic acid; propylene glycol, trimethylene glycol, and diethyl Glycol, tetramethylene glycol, hexamethylene glycol, neopentylene glycol, p-xylylene glycol (bis-p- [hydroxymethyl] benzene), 1,4-cyclohexanedimethanol, bisphenol A, p, p'-dihydroxy Phenylsulfone (bisphenol S), 1,4-bis (β-hydroxyethoxy) benzene, 2,2-bis (p-β-hydroxyethoxyphenyl) propane, bis (p-β-hydroxyethoxyphenyl) sulfone, polyalkylene Oxy compounds such as glycol and p-phenylenebis (dimethylcyclohexane), or functional derivatives thereof; high polymerization compounds derived from the carboxylic acids, oxycarboxylic acids, oxy compounds or functional derivatives thereof; ) Compounds having a number of ester-forming functional groups, for example, benzoic acid, benzoyl benzoic acid, benzyloxy benzoic acid, and the like methoxy polyalkylene glycol. Furthermore, (c) compounds having three or more ester-forming functional groups, such as glycerin, pentaerythritol, trimethylolpropane, tricarballylic acid, trimesic acid, trimellitic acid, pyromellitic acid, It can be used within a linear range.

  As a method for producing the polyester constituting the polyester composition of the present invention, a generally known production method is used. That is, first, a glycol ester of dicarboxylic acid and / or a low polymer thereof is produced by a direct esterification reaction of a dicarboxylic acid component such as terephthalic acid and a glycol component such as ethylene glycol. Alternatively, a dicarboxylic acid glycol ester and / or a low polymer thereof is produced by a transesterification reaction in the presence of a dicarboxylic acid component such as dimethyl terephthalate, a diol component such as ethylene glycol, and a transesterification catalyst. Next, this low polymer is heated under reduced pressure in the presence of a polymerization catalyst and subjected to a polycondensation reaction until a predetermined degree of polymerization is obtained, whereby the desired polyester is produced.

<Intrinsic viscosity of polyester>
The intrinsic viscosity (solvent: orthochlorophenol, measurement temperature: 35 ° C.) of the polyester constituting the polyester composition of the present invention is not particularly limited, but is preferably in the range of 0.5 to 1.5 dL / g. When the intrinsic viscosity is less than 0.5, the mechanical properties of the resulting polyester fiber are insufficient, and when it exceeds 1.5, the melt moldability is undesirably lowered. The intrinsic viscosity of the polyester is 0.6 to The range of 0.1.3 dL / g is more preferable.

<About aluminum compounds>
The polyester composition of the present invention must contain at least one aluminum compound selected from the group consisting of an inorganic compound containing a metal aluminum atom and an organic aluminum compound in a range satisfying the following mathematical formula (1). .
0.01 wt% ≦ Al ≦ 10.0 wt% (1)
[In the above formula, Al represents the mass percent concentration of aluminum with respect to the polyester composition. ]

  When the content of the aluminum compound relative to the polyester composition is less than 0.01 wt%, the antibacterial activity is low, which is not preferable. When the content of the aluminum compound exceeds 10.0 wt%, the resulting polyester composition has a high melt viscosity and low melt moldability, which is not preferable. The range of the amount of aluminum contained in the aluminum compound is preferably 0.02 to 9.0 wt% or more, and more preferably 0.04 to 8.0 wt%. And as metal aluminum, in order to maintain the moldability of the obtained polyester resin, it is preferable that an average primary particle size is in the range of 0.1 μm to 10 μm.

<Examples of aluminum compounds>
As the organoaluminum compound used in the polyester composition of the present invention, the organoaluminum compound represented by the following formula (2) is preferable because it has high affinity with the polyester, is uniformly dispersed, and has excellent moldability. .
Al (OX ¹ ) (OX ² ) (OX ³ ) (2)
[In the above ^formula, X 1 to X ³ is a hydrocarbon residue of also 2 to 8 carbon atoms include an oxygen atom. X ^{1 to} X ³ may be the same functional group or different functional groups. ]

Examples of the functional group of OX ^{1 to} OX ³ include an alcoholate group, a phenolate group, an aliphatic, alicyclic or aromatic carboxyl group, and more specifically, a methylate group, an ethylate group, a propylate group, and a butyrate. Groups, pentylate groups, hexylate groups, these alkylate groups containing one or more ether groups, phenolate groups, formate anion, acetate anion, propionate anion, butyrate anion, valerate anion, benzoate anion, glycolic acid anions, lactate anions, acrylic acid anion, methacrylic acid anions, oxalate anions, malonate anions, succinate anions, glutaric acid anion, adipic acid anions, tartrate anions, mention may be made of an acetyl acetonate group, X ¹ ~ each functional group of X ³ are single Even functional group, it may be a 2 or more of a plurality of types of functional groups.

  Examples of such organoaluminum compounds include aluminum trisacetylacetonate, aluminum acetate, aluminum lactate, aluminum triisopropoxide, aluminum trisec-butylate, aluminum triethylate, aluminum propionate, aluminum oxalate, and acrylic acid. Aluminum, aluminum benzoate, aluminum citrate, aluminum tartrate, aluminum salicylate and other carboxylates, aluminum methylate, aluminum t-butoxide and other aluminum alkoxides, aluminum acetyl acetate, aluminum ethyl acetyl acetate and other aluminum chelate compounds List reaction products consisting of aluminum chelates and hydroxycarboxylic acids Can. Of these, at least one aluminum compound selected from the group consisting of aluminum trisacetylacetonate, aluminum acetate, aluminum lactate, aluminum triisopropoxide, aluminum trisec-butylate and aluminum triethylate is preferably used. Most preferred are narate, aluminum acetate, aluminum lactate and aluminum sec-butylate.

  On the other hand, specific examples of inorganic compounds containing metal aluminum atoms include aluminum oxide, ultrafine aluminum oxide, aluminum silicate, and composite oxides of aluminum and titanium, silicon, zirconium, alkali metals, alkaline earth metals, and the like. The

<Aluminum compound addition time>
Here, the addition time of the aluminum compound during the production of the polyester is not particularly limited, but it can be added at any stage where the polymerization reaction is completed before the start of the transesterification reaction. Moreover, when the addition method by the kneading | mixing mentioned later is employ | adopted, it is also possible to add just before shaping | molding process after superposition | polymerization of polyester.

<Method of adding aluminum compound>
Furthermore, examples of the addition method to the polyester include a method of adding the aluminum compound in a powder state and a method of adding the slurry after preparing a slurry dispersed in a solvent. The method of adding as a slurry is preferable because coarse particles can be filtered through a filter by filtering the aluminum compound slurry. Solvents in which the particulate compound is dispersed include low-boiling solvents such as water, methanol, ethanol, propanol, butanol, acetone, tetrahydrofuran, 1,4-dioxane, toluene, and xylene, and ethylene glycol, propylene glycol, butylene glycol, and the like. Examples of the diol component constituting the polyester include a solvent and a mixture of these solvents. As the solvent, ethylene glycol, isopropanol, and butanol are preferable because the aluminum compound can be uniformly dissolved. When adjusting the slurry of the aluminum compound, a dispersant can be added as necessary.

<Dry addition method of aluminum compound>
Moreover, as a manufacturing method of this polyester composition, the addition method by kneading | mixing to the polyester of a molten state is employable. The method of kneading is not particularly limited, but it is preferable to use a normal uniaxial or biaxial kneader. More preferably, in order to suppress a decrease in the degree of polymerization of the resulting polyester composition, a method of using a vented uniaxial or biaxial kneader can be exemplified.

  The conditions during the kneading are not particularly limited. For example, the melting point is higher than the melting point of the polyester and the residence time is within 1 hour, preferably 1 minute to 30 minutes. Moreover, the supply method of the aluminum compound and polyester to a kneading machine is not specifically limited. For example, a method of supplying an aluminum compound and polyester separately to a kneader by a dry method, a method of appropriately mixing and supplying an aluminum compound and polyester, and the like can be mentioned.

<About transesterification catalyst>
The transesterification catalyst used in the method for producing the polyester constituting the polyester composition of the present invention is not particularly limited, and a conventionally known transesterification catalyst can be used. For example, lithium, sodium, potassium, magnesium, calcium, strontium, barium, titanium, manganese, cobalt, zinc, and an aluminum compound can be used. Examples of such compounds include oxides, acetates, carboxylates, hydrides, alcoholates, halides, carbonates, sulfates and the like of each metal compound. Moreover, these compounds may use 2 or more types together. Moreover, when using an aluminum compound as a transesterification catalyst, it is also possible to use the aluminum compound which is an antimicrobial component used for this invention as a catalyst.

<About polymerization catalyst>
Although it does not specifically limit about the ester polymerization catalyst used with the manufacturing method of polyester which comprises the polyester composition of this invention, Antimony, titanium, germanium, aluminum, a zirconium, and a tin compound can be used. Examples of such a compound include antimony, titanium, germanium, aluminum, zirconium, tin oxide, acetate, carboxylate, hydride, alcoholate, halide, carbonate, sulfate and the like. Moreover, these compounds may use 2 or more types together. Moreover, when using an aluminum compound as a polymerization catalyst, it is also possible to use the aluminum compound which is an antimicrobial component used for this invention as a catalyst.

An antimony compound is preferably used because it has high polymerization activity and is easily available. In this case, the amount of the antimony compound is preferably contained in a range satisfying the following mathematical formula (2).
10 mmol% ≦ Sb ≦ 50 mmol% (2)
[In the above formula, Sb represents the millimole percent concentration of antimony with respect to all the acid components constituting the polyester. ]
If the content of the antimony compound is less than 10 mmol%, the polymerization activity is insufficient, and if it exceeds 50 mmol%, a side reaction occurs during the polycondensation reaction, and a large amount of inappropriate side-reactive products may be generated. Is not preferable.

<Others>
The polyester composition of the present invention contains a small amount of additives as required, such as lubricants, phosphorus compound stabilizers, radical scavengers, antioxidants, solid phase polymerization accelerators, color adjusters, fluorescent whitening agents, antibacterial agents An agent, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a light-shielding agent, a flame retardant, or a matting agent may be included.
Moreover, the polyester composition of the present invention can be melt-molded to obtain polyester molded products such as films, molded products, and fibers. There is no limitation in particular as a manufacturing method when manufacturing the polyester molded product of this invention by melt molding, A conventionally well-known method is used.

The production method for producing the polyester fiber of the present invention by melt spinning is not particularly limited, and conventionally known melt spinning methods are used. For example, it is preferable to produce a dried polyester composition by melt spinning at a temperature in the range of 270 ° C. to 300 ° C., and the spinning speed of the melt spinning can be 400 to 9000 m / min. It is possible to increase the strength of the material.
Also, the shape of the die used at the time of spinning is not particularly limited, and any of circular shape, irregular shape, solid shape or hollow shape can be adopted. Furthermore, the polyester fiber of the present invention is preferably subjected to an alkali weight reduction treatment in order to enhance the texture.

The present invention will be further described in the following examples, but the scope of the present invention is not limited by these examples. Various characteristics were measured by the following methods.
(A) Intrinsic viscosity:
A dilute solution obtained by dissolving a polyester composition chip in orthochlorophenol at 100 ° C. for 60 minutes was determined from a value measured at 35 ° C. using an Ubbelohde viscometer. In addition, the compound which becomes obstructive at the time of viscometer use, such as the inorganic compound contained in a composition, was removed by filtration etc. before the measurement.
(A) Metal element content in the polyester composition:
The amount of metal element in the polyester composition was such that a granular polyester composition sample was heated and melted on a steel plate, and then a test molded body having a flat surface was prepared with a compression press. Using this test molded body, it was determined using a fluorescent X-ray apparatus (Model 3270E manufactured by Rigaku Corporation).
(C) Bacteriostatic activity value:
Using a test bacterial suspension of Staphylococcus aureus ATCC 6538P, a bacterial liquid absorption method based on JIS L1902 (2008 revised edition) was performed.
(Bacteriostatic activity value) = (Mb)-(Mc)
(Mb represents the average value of the logarithm of the number of viable bacteria in three specimens after 18 hours of culture on a cotton standard white cloth.)
(Mc represents the average value of the logarithm of the number of viable bacteria of three specimens after 18 hours of sample cloth culture.)
When the bacteriostatic activity value was 2.2 or more, the antibacterial property was judged to be good.
(D) Formability:
The actually obtained polyester chip sample was dried at 160 ° C. for 6 hours under a nitrogen stream, and then melt-spun under the conditions of a spinning temperature of 290 ° C., a nozzle hole diameter of 0.27 mm, and a number of holes of 24. The product from which the yarn sample was obtained during the spinning time of 5 minutes was marked with “◯”, and the yarn sample that could not be obtained due to process failure such as yarn breakage was judged as “x”.

[Example 1]
-Production of polyester composition chip To a mixture of 194.2 parts by mass of dimethyl terephthalate (DMT) and 124.2 parts by mass of ethylene glycol (200 mol% relative to DMT), 0.025 parts by mass of manganese acetate tetrahydrate ( 10 mmol% relative to DMT) was charged into a SUS (stainless steel) container. The ester exchange reaction was completed while raising the temperature from 140 ° C. to 240 ° C. under normal pressure. Thereafter, 0.145 parts by mass of diantimony trioxide (50 mmol% relative to DMT) was added to the reaction product, followed by 0.971 parts by mass of aluminum trisacetylacetonate (the amount of aluminum was 0 with respect to the amount of the finally obtained polyester composition). 0.042 mass percent) was added and transferred to a reaction vessel equipped with a stirrer, nitrogen inlet, vacuum port and distillation apparatus. The internal temperature of the reaction vessel was raised to 285 ° C., and a polycondensation reaction was performed at a high vacuum of 30 Pa or less to obtain a polyester composition having an intrinsic viscosity of 0.64 dL / g. Furthermore, it was made into a chip according to a conventional method.

・ Manufacture of polyester tube net sample A polyester chip sample was dried at 160 ° C. under a nitrogen stream for 6 hours, and then melt-spun and stretched under the conditions of a spinning temperature of 290 ° C., a nozzle hole diameter of 0.27 mm, and the number of holes of 24, and 84 dtex (24 fil) Polyester fibers were obtained. The obtained polyester fiber was made into a tubular mesh test piece with a tubular knitting machine by a conventional method, and the antibacterial and antibacterial activity value of the test piece was measured. The bacteriostatic activity value was 2.3. The results are shown in Table 1.

[Examples 2-5, Comparative Examples 1-5]
In Example 1, it carried out like Example 1 except having changed the kind and quantity of an aluminum compound, and the quantity of diantimony trioxide into the description of Table 1. The results are shown in Table 1.

  According to the present invention, a polyester composition having high antibacterial properties and excellent molding processability such as yarn production can be obtained. As a result, various molded products having high antibacterial properties, such as films, resins, and fibers, can be produced by various subsequent moldings. The results are shown in Table 1.

Claims (8)

A polyester composition comprising at least one aluminum compound selected from the group consisting of an inorganic compound containing a metal aluminum atom and an organoaluminum compound, wherein the polyester composition is contained in a range satisfying the following mathematical formula (1): object.
0.01 wt% ≦ Al ≦ 10.0 wt% (1)
[In the above formula, Al represents the mass percent concentration of aluminum atoms relative to the polyester composition. ] A polyester composition characterized in that the organoaluminum compound is represented by the following chemical formula (2).
Al (OX ¹ ) (OX ² ) (OX ³ ) (2)
[In the above ^formula, X 1 to X ³ is a hydrocarbon residue of also 2 to 8 carbon atoms include an oxygen atom. X ^{1 to} X ³ may be the same functional group or different functional groups. ]   The organoaluminum compound is at least one aluminum compound selected from the group consisting of aluminum trisacetylacetonate, aluminum acetate, aluminum lactate, aluminum triisopropoxide, aluminum trisec-butylate, and aluminum triethylate. The polyester composition according to claim 2. The polyester composition according to claim 3, comprising an antimony atom as a polymerization catalyst for polymerizing the polyester composition in a range satisfying the following mathematical formula (2).
10 mmol% ≦ Sb ≦ 50 mmol% (2)
[In the above formula, Sb represents the millimole percent concentration of antimony atoms with respect to all acid components constituting the polyester. ]   The polyester composition according to any one of claims 1 to 3, wherein the polyester contained in the polyester composition is polyethylene terephthalate.   A polyester molded article obtained by melt-molding the polyester composition according to claim 1.   A polyester fiber obtained by melt spinning the polyester composition according to claim 1.   A processed polyester fiber product comprising the polyester fiber according to claim 7.