JP2019059840A - Polyester resin composition - Google Patents

Abstract

To provide a polyester resin composition having excellent resistance to thermal oxidative degradation and also excellent workability.SOLUTION: A polyester resin composition contains polyalkylene glycol 0.1-20 wt.% and satisfies formula 1: TGA/PAG≤0.4 (1), where TGA is a thermal weight loss (unit: wt.%) at 280°C for 60 minutes under dry air circulation and PAG is a content of polyalkylene glycol content (unit: wt.%).SELECTED DRAWING: None

Description

  The present invention relates to a polyester resin composition excellent in thermal oxidative degradation and processability.

Polyester represented by polyethylene terephthalate is excellent in mechanical properties, thermal properties, chemical resistance, electrical properties and moldability, and is used in various applications. In these polyesters, it is often carried out to introduce polyalkylene glycol as a copolymerization component to impart processability. (Patent Document 1)
Polyalkylene glycol copolymerized polyester is usually obtained by polycondensation reaction of an aromatic dicarboxylic acid or its lower alkyl ester as a dicarboxylic acid component, and an aliphatic glycol and a polyalkylene glycol as a diol component through an esterification reaction or a transesterification reaction. can get.

  However, polyalkylene glycol copolymerized polyester is inferior in heat resistance to polyethylene terephthalate and the like, and therefore, is easily decomposed during polycondensation reaction and molding processing.

In order to solve this drawback, proposals have been made as shown in the following documents.
In Patent Document 2, the oxidative decomposition is performed by adding 0.02 to 3% by weight of a hindered phenol-based antioxidant to a polyester composition obtained by copolymerizing 1 to 20% by weight of polyethylene glycol having a number average molecular weight of 400 to 30000. Suppressing polyester fibers have been proposed.

  In Patent Document 3, 0.0025 to 0.15% by weight of a hindered phenol-based antioxidant is added to a polyester composition obtained by copolymerizing 0.5 to 5.0% by weight of polyethylene glycol having a number average molecular weight of 600 to 4000. The polyester fiber which suppresses oxidative degradation by doing is proposed.

Japanese Patent Application Laid-Open No. 8-100056 JP, 2004-293024, A JP, 2005-272504, A

  However, since these techniques depend on the addition amount of the hindered phenol-based antioxidant, when added in a large amount, the hindered phenol-based antioxidant becomes foreign matter, so the processability is inferior, and a small amount of addition causes sufficient oxidation. There is a problem that it does not have the ability to prevent deterioration, and the physical properties deteriorate due to oxidative decomposition during processing.

  An object of the present invention is to overcome the problems of the prior art and to provide a polyester composition having excellent processability and good resistance to thermal oxidative degradation.

  As a result of examining in order to solve the above-mentioned subject, according to the present invention, the polyester resin composition which makes compatible good heat-resistant oxidative decomposability and processability was discovered.

That is, the object of the present invention is achieved by the following means.
(1) A polyester resin composition containing 0.1 to 20 wt% of a polyalkylene glycol, and satisfying the formula 1.

TGA / PAG ≦ 0.4 (1)
Here, TGA is a thermal weight reduction rate (unit wt%) in dry air circulation at 280 ° C. for 60 minutes, and PAG is a content of polyalkylene glycol (unit wt%).
(2) The polyester resin composition according to (1), which contains a metal element having a standard redox potential of −1.70 V or more and an alkali metal element and satisfies the formula 2.

0.01 ≦ B / M ≦ 30 (2)
Here, M is the content (unit mol / t) of the metal element having a standard redox potential of −1.70 V or more, and B is the content (unit mol / t) of the alkali metal element.
(3) The polyester resin composition as described in (1) or (2) which contains 0.01-30 mol / t of Cu elements.
(4) The polyester resin composition according to any one of (1) to (3), wherein the polyalkylene glycol is polyethylene glycol.
(5) The polyester resin composition as described in (1) to (4) containing 0.1 wt% or more and 20 wt% or less of an antistatic agent.
(6) The polyester resin composition according to (5), wherein the antistatic agent is an anionic antistatic agent.
(7) The polyester resin composition according to any one of (1) to (6), which contains a phenolic antioxidant.

  ADVANTAGE OF THE INVENTION According to this invention, the polyester resin composition which makes favorable heat-resistant oxidative degradability and processability make compatible can be provided.

The present invention will be described in detail below.
The polyester resin in the present invention refers to a polyester resin obtained by polycondensation using a dicarboxylic acid component and a diol component consisting of a glycol component and a polyalkylene glycol component as a main raw material. The main raw material indicates that the constituent units obtained from the dicarboxylic acid component and the diol component in the polymer are 70 mol% or more in total. More preferably, it is 80 mol% or more, further preferably 90 mol% or more.

  Examples of the dicarboxylic acid component in the present invention include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, aromatic dicarboxylic acids, and ester derivatives thereof. Among them, an aromatic dicarboxylic acid component is preferable from the viewpoint of the heat-resistant oxidative decomposability of the polyester resin composition and the processability. Furthermore, it is preferable that the aromatic dicarboxylic acid component is 95 mol% or more as the dicarboxylic acid component from the viewpoint of resistance to oxidative degradation, and in particular, terephthalic acid is preferred from the viewpoint of both heat resistant oxidative degradation and processability.

  The glycol component in the present invention includes aliphatic diols, alicyclic diols, and aromatic cyclic diols. In addition to diols, polyfunctional alcohols such as trimethylolpropane and pentaerythritol can also be used as long as they do not gel. In particular, it is preferable that 90 mol% or more of the glycol component not containing a polyalkylene glycol is an aliphatic diol. Among them, for example, ethylene glycol is particularly preferable from the viewpoint of mechanical properties such as elongation and flexibility when the composition is formed into a film.

  The polyester resin composition in the present invention is required to contain a polyalkylene glycol component. Specific examples of the polyalkylene glycol component include polyethylene glycol, polypropylene glycol, polytrimethylene ether glycol, polytetramethylene glycol, polyhexamethylene ether glycol, block or random copolymer of ethylene oxide and propylene oxide, ethylene glycol Or a block copolymer or a random copolymer of 1,4-butanediol and the like, and two or more of them may be used in combination, and among them, polyethylene glycol and polytetramethylene glycol are particularly preferable as copolymerizable polyesters. In terms of processability, polyethylene glycol is particularly preferably used. In particular, as the number average molecular weight of polyethylene glycol is 400 or more and 10000 or less, the dispersibility of polyethylene glycol in the polyester resin composition is improved, and the heat oxidative degradation resistance is improved, and also at the time of melt molding (film etc.) The discharge stability from the nozzle of the above tends to be good, which is preferable. In addition, when the dispersibility of polyethylene glycol in the polyester resin composition is improved, a molded article having high transparency can be easily obtained, which is preferable because it can be suitably used in wider applications. The lower limit of the more preferable number average molecular weight is 600 or more, and the upper limit is 6000 or less.

  The content of the polyalkylene glycol is required to be 0.1 wt% or more and 20 wt% or less. By setting it as the said minimum or more, the molecular mobility of the polyester resin composition at the time of shaping | molding increases, fluidity improves, and it is excellent in processability. By setting the content to the above upper limit or less, it is possible to achieve both good thermal oxidative degradation resistance and mechanical properties inherent to polyester. From the viewpoint of processability, the lower limit of the polyalkylene glycol content is more preferably 1.0 wt% or more. The upper limit is more preferably 10 wt% or less from the viewpoint of the mechanical properties and the thermal oxidative degradation of the polyester resin composition.

  Other dicarboxylic acids, hydroxycarboxylic acid derivatives and diols may be copolymerized to the extent that the range of the effects of the present invention is not impaired. In each component, by setting the copolymerization component to 5 mol% or less, it is preferable from the point of being able to suppress a decrease in thermal oxidative degradation and a decrease in crystallinity due to a decrease in melting point.

  The polyester resin composition of the present invention has a ratio (TGA, unit: wt%) of the thermal weight loss ratio (TGA, unit: wt%) under dry air circulation to the content (PAG, unit: wt%) of the polyalkylene glycol (TGA) It is necessary that / PAG) be 0.40 or less. By setting it as the said upper limit or less, bubble generation | occurrence | production and the coloring of a molded object by the thermal oxidation decomposition at the time of processing can be suppressed. The TGA / PAG is preferably 0.35 or less, more preferably 0.30 or less from the viewpoint of heat-resistant oxidative decomposability and processability.

  The processability of the present invention is evaluated by the complex viscosity η * 1 at an angular velocity ω = 1.25 rad / sec when performing dynamic viscoelasticity measurement with a rheometer. When η * 1 is 100 Pa · sec or more and 400 Pa · sec or less, the flowability is sufficient and it is easy to handle, so the processability is good. The lower limit of η * 1 is preferably 150 Pa · sec or more, and the upper limit is preferably 350 Pa · sec or less.

Also, let η * 1 be the complex viscosity at angular velocity ω = 1.25 rad / sec, and η * 2 be the complex viscosity at angular velocity ω = 62.83 rad / sec (measurement frequency 10 Hz), and equation (3) Calculate the rate of change of the complex visco modulus.
Rate of change = (η * 1-* * 2) / * * 2 (3)
Usually, when a multi-functional component that crosslinks is added, or when it has a phase separation structure, the complex visco modulus changes largely depending on the shear rate, and the difference shown in equation (3) is a large numerical value and Become. As the difference is a larger value, the ballistic effect is more easily developed, and problems such as destabilization and molding failure when discharging the molten polyester resin composition from a die tend to occur. Therefore, the smaller the difference in equation (3), the better the melt stability at the time of discharge or molding. It is preferable that this change rate is 0.2 or less.

  In the polyester resin composition of the present invention, the content M of the metal element having a standard redox potential of −1.70 V or more, including a metal element having a standard redox potential of −1.70 V or more and an alkali metal element The ratio B / M of mol / t) to the content B of alkali metal element (mol / t) is 0.01 or more and 30 or less, thereby suppressing shear rate dependency due to gelation generated during melt processing It is preferable at the point which can be provided and can provide the polyester resin composition excellent in the melt stability at the time of discharge of a melt | dissolved polyester resin composition, or shaping | molding.

  The term "containing a metal element having a standard redox potential of -1.70 V or more and a basic compound" as used in the present invention means being contained in the polyester resin composition and in the polyester resin composition. There is no limitation on the chemical form.

  The standard redox potential of the present invention is the value at 25 ° C. As metal elements having a standard redox potential of −1.70 V or more, Al, Ti, Zr, Mn, Ta, Zn, Cr, Fe, Cd, Co, Ni, Sn, Pb, Sb, Bi, Cu, Hg, Ag, Pd, Ir, Pt, Au and the like can be mentioned, but from the viewpoint of transparency, Cu, Ag, Pd, Pt, Au, Fe, Zn is preferable.

  By making B / M into said numerical range, the processability and heat-resistant oxidative degradability of the polyester resin composition obtained become more favorable. This is a specific effect due to the coexistence of the metal element and the alkali metal element having a standard redox potential of −1.70 V or more at a specific ratio. The lower limit of B / M is more preferably 0.1 or more, and still more preferably 0.5 or more. On the other hand, the upper limit of B / M is more preferably 10 or less, and still more preferably 7 or less.

  The alkali metal element acts as a basic compound for reducing and finely dispersing a metal having a standard redox potential of -1.70 V or more. A basic compound is a compound that meets the definition of a Lewis base or Arrhenius base. Among them, alkali metal hydroxides are more preferable. When an alkali metal hydroxide is contained, a polyester composition excellent in heat-resistant oxidative degradation is obtained. Moreover, 2 or more types of basic compounds can also be contained.

  In the polyester resin composition of the present invention, the Cu element is preferably contained in an amount of 0.01 mol / t or more and 30 mol / t or less. By setting the Cu element to the above lower limit or more, the heat-resistant oxidative decomposability can be improved, and by setting the Cu element or below to less than the upper limit, the generation of foreign substances due to the aggregation of the Cu element can be suppressed to improve the transparency. The lower limit of the content of the Cu element is more preferably 0.5 mol / t or more, and the upper limit is more preferably 5 mol / t or less.

  In the polyester resin composition of the present invention, when the metal element having a standard redox potential of −1.70 V or more is a Cu element, the ratio B / M2 of the content M2 of Cu element to the content B of alkali metal element is It is preferable that it is 0.01 or more and 30 or less. A polyester resin composition containing a Cu element is excellent in heat-resistant oxidative decomposability, but it is preferable that coexistence of the Cu element and a basic compound allows coexistence of suppression of Cu-derived foreign matter aggregation and heat-resistant oxidative decomposability.

  By making B / M2 into said numerical range, the transparency and the heat-resistant oxidative degradation property of the polyester resin composition obtained become more favorable. The lower limit of B / M 2 is more preferably 0.1 or more, and still more preferably 0.5 or more. The upper limit of B / M 2 is more preferably 10 or less, and still more preferably 7 or less.

  The polyester resin composition of the present invention preferably further contains an antistatic agent in an amount of 0.1 wt% or more and 20 wt% or less. Since polyester is liable to generate static electricity, it has the disadvantage that various troubles are likely to occur at the time of production, processing and use. However, the inclusion of the antistatic agent makes it possible to suppress the static electricity generated in each step. As an antistatic agent, although a well-known thing can be used, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, an ionic liquid, a conductive polymer etc. are mentioned, for example. Among them, anionic surfactants are more preferable from the viewpoint of heat resistance and transparency of the polyester resin composition. Also, two or more antistatic agents may be used in combination.

  The anionic surfactant may, for example, be a carboxylate, a sulfonate, a sulfate, a phosphate or the like. Among them, sulfonates are preferred from the viewpoint of antistatic properties and heat resistance. As a sulfonate, specifically, sodium hexane sulfonate, sodium octane sulfonate, sodium decane sulfonate, sodium dodecane sulfonate, perfluorobutane sulfonic acid, sodium toluene sulfonate, sodium cumene sulfonate, sodium octyl benzene sulfonate , Sodium dodecyl benzene sulfonate, lithium dodecyl benzene sulfonate, ammonium dodecyl benzene sulfonate, sodium naphthalene sulfonate, disodium naphthalene disulfonate, trisodium naphthalene trisulfonate, sodium butyl naphthalene sulfonate, lithium perfluorooctane sulfonate, etc. Among them, from the viewpoint of antistatic property, heat resistance, manufacturing cost, and suppression of foreign matter generation during processing. Sodium dodecyl benzene sulfonate, lithium dodecylbenzenesulfonate, ammonium dodecylbenzenesulfonate is more preferred.

  The content of the antistatic agent may be in a range that does not impair the effects of the present invention, and although depending on the performance of the antistatic agent, the content is preferably 0.1 wt% to 20 wt%. More preferably, it is 0.5 wt% or more and 10 wt% or less.

  In the polyester resin composition of the present invention, it is preferable to contain a phenolic antioxidant in view of the ability to improve the thermal oxidative degradation. In addition, by using a metal element and an alkali element having a standard redox potential of −1.70 V or more in combination with a phenol-based antioxidant, it is possible to further improve the thermal oxidative degradation. In particular, the oxidation decomposition resistance can be further improved by selecting a Cu compound as a metal element having a standard redox potential of −1.70 V or more.

  As a phenol type antioxidant used by the polyester resin composition of this invention, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris ( 4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid and the like, among which pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] is It is preferable because the suppression of coloring and the resistance to oxidative degradation become good. The content of the antioxidant is preferably 0.01 wt% or more and 0.5 wt% or less. When the content is in the above range, the heat-resistant oxidative degradability and the processability can be improved, and the coloring by the antioxidant and the generation of foreign matter can be suppressed.

Next, the method for producing the polyester resin composition of the present invention will be described.
The method for producing the polyester resin composition of the present invention comprises, as main raw materials, a diol component consisting of a dicarboxylic acid component or an ester thereof, a glycol component and a polyalkylene glycol component, and comprises the following two steps. That is, the first step consisting of (A) esterification reaction or (B) transesterification reaction, and the second step consisting of (C) polycondensation reaction which follows.

  As raw materials for producing the polyester composition of the present invention, dicarboxylic acids or dicarboxylic esters, glycols and polyalkylene glycols can be used, and each of them can be used alone or in combination of two or more. .

  As the dicarboxylic acid or dicarboxylic acid ester of the present invention, terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, diphenyl 4,4'-dicarboxylic acid, 5-sodium sulfoisophthalic acid, oxalic acid, succinic acid, adipic acid Sebacic acid, malonic acid, dimer acid, or alkyl esters thereof. The dicarboxylic acid ester referred to in the present invention is the lower alkyl ester of dicarboxylic acid described above, an acid anhydride, an acyl chloride and the like, and a methyl ester, an ethyl ester, a hydroxyethyl ester and the like are preferably used. A more preferable embodiment as the dicarboxylic acid or dicarboxylic acid ester of the present invention is terephthalic acid or an ester thereof in that a polyester composition having a high melting point and being easy to process into a film, a fiber or the like can be obtained.

  Aliphatic diols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, butanediol, 2-methyl-1,3-propanediol, hexanediol, neopentyl glycol and the like as the glycol of the present invention Alicyclic diols such as cyclohexanedimethanol, cyclohexanediethanol, 2,6-dihydroxy-9-oxabicyclo [3,3,1] nonane, 3,9-bis (2-hydroxy-1,1-dimethylethyl)- 2,4,8,10-Tetraoxaspiro [5,5] undecane (spiro glycol), 5-methylol-5-ethyl-2- (1,1-dimethyl-2-hydroxyethyl) -1,3-dioxane , Saturated heterocyclic primary diols containing cyclic ethers such as isosorbide, other paraxylenes Aromatic cyclic diols such as Cole, bisphenol A, bisphenol S, styrene glycol, 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene and 9,9'-bis (4-hydroxyphenyl) fluorene it can. In addition to diols, polyfunctional alcohols such as trimethylolpropane and pentaerythritol can also be used as long as the effects of the present invention are not impaired. Ethylene glycol is preferred in that the effects of the present invention can be sufficiently achieved and a polyester resin composition that can be easily processed into a film, a fiber, etc. can be obtained.

  The polyalkylene glycols of the present invention include polyethylene glycol, polypropylene glycol, polytrimethylene ether glycol, polytetramethylene glycol, polyhexamethylene ether glycol, block or random copolymer of ethylene oxide and propylene oxide, ethylene glycol and 1, A block or random copolymer with 4-butanediol may, for example, be mentioned, and two or more of them may be used in combination. Among them, polyethylene glycol and polytetramethylene glycol are preferable in view of processability of copolymerized polyester. Particularly, polyethylene glycol is particularly preferably used from the viewpoint of processability. In addition, as the number average molecular weight of polyethylene glycol is 400 or more and 10000 or less, the dispersibility of polyethylene glycol in the polyester resin composition is improved, and the heat resistant oxidative degradation is improved, and also at the time of melt molding (film etc.) The discharge stability from the nozzle of the above tends to be good, which is preferable. A more preferable average molecular weight is 600 or more and 6000 or less.

  In the production method of the present invention, in the first step, in the step of esterification reaction, the dicarboxylic acid component and the diol component are subjected to an esterification reaction at a predetermined temperature until a predetermined amount of water is distilled. The reaction is carried out to obtain a low polymer. When a low polymer is obtained by the esterification reaction, the molar ratio of the dicarboxylic acid component to the diol component (diol component / dicarboxylic acid component) before initiation of the esterification reaction is 1.05 from the viewpoint of esterification reactivity and heat resistance. It is preferable that it is a range of not less than 1.40. More preferably, it is 1.05 or more and 1.30 or less, more preferably 1.05 or more and 1.20 or less. By setting it in the above-mentioned range, since it has a good reactivity and can suppress the formation of by-products such as a dimer of a diol component, it is possible to improve the thermal oxidative degradation.

  The step of (B) transesterification is a step of transesterification between a dicarboxylic acid alkyl ester and a diol component to obtain a low polymer by reaction until a predetermined amount of alcohol is distilled. When obtaining a low polymer by transesterification, from the viewpoint of reactivity and heat resistance, the molar ratio of the dicarboxylic acid alkyl ester to the diol component (diol component / dicarboxylic acid alkyl ester) is 1.7 or more and 2.3 or less It is preferable that it is a range. By setting it as the said range, transesterification can be advanced efficiently and by-product of the dimer component of a diol component can be suppressed, Therefore Heat-resistant oxidative degradability can be made favorable.

  Of the second step, the (C) polycondensation reaction is a step of obtaining a polyester resin composition from a low polymer obtained by (A) esterification reaction or (B) transesterification reaction. The polyalkylene glycol can be any of the first step consisting of (A) esterification reaction or (B) transesterification reaction as a diol component, and any of the second step consisting of (C) polycondensation reaction following it. Although it may be added, it is preferable to be added in the second step consisting of (C) polycondensation reaction in that the heat-resistant oxidative decomposability can be made good.

  Moreover, batch polymerization, semicontinuous polymerization, and continuous polymerization can be applied to the production method of the present invention.

  In the method for producing the polyester composition of the present invention, the catalyst used for the esterification reaction (A) may use a compound such as manganese, cobalt, zinc, titanium, calcium or the like, but the heat at the polycondensation reaction stage is From the viewpoint of decomposition and generation of foreign matter, it is preferable to carry out the esterification reaction without using a catalyst. Here, the (A) esterification reaction proceeds sufficiently without catalyst even by the autocatalysis of carboxylic acid. Moreover, as a catalyst used for (B) transesterification, a well-known transesterification catalyst can be used. Examples of transesterification catalysts include organic manganese compounds, organic magnesium compounds, organic calcium compounds, organic cobalt compounds, organic lithium compounds, etc. Specifically, carbonates, acetates, benzoates, oxides, hydroxides Although there is a thing etc., it is not limited to this.

  Moreover, as a catalyst used for (C) polycondensation reaction, a well-known polycondensation catalyst can be used. For example, compounds such as antimony, titanium, aluminum, tin, germanium and the like can be mentioned.

  Examples of the antimony compound include oxides of antimony, carboxylates of antimony, and antimony alkoxides.

  Examples of titanium compounds include titanium chelate complexes, titanium alkoxides, and titanium oxides obtained by hydrolysis of titanium alkoxides.

  As an aluminum compound, aluminum carboxylate, an aluminum alkoxide, an aluminum chelate compound, a basic aluminum compound etc. are mentioned.

  Examples of the tin compound include tin compounds having an alkyl group and tin compounds having a hydroxyl group.

  The germanium compound may, for example, be an oxide of germanium or a germanium alkoxide.

The above metal compound may be a hydrate.
Among them, it is preferable to use an antimony compound or a titanium compound as a polycondensation reaction catalyst from the viewpoint of polymerization time, color tone and production cost.

  In the method for producing a polyester resin composition of the present invention, a compound containing a metal element having a standard redox potential of -1.70 V or more and a basic compound are added, and the standard redox potential is -1.70 V or more The ratio B2 / M3 of the addition amount M3 (mol / t) of the compound containing the metal element to the addition amount B2 (mol / t) of the basic compound is 0.01 or more and 30 or less. It is preferable at the point which can obtain the polyester resin composition excellent in the processability which suppresses the viscosifying by gelatinization.

  In the method for producing a polyester resin composition of the present invention, a metal compound containing a metal element having a standard redox potential of -1.70 V or more, and a basic compound are the above (A) esterification reaction or (B) transesterification reaction. Although it may be added at any stage of the process and the subsequent polycondensation reaction process, it is possible to obtain a polyester composition having good transparency by adding it before the completion of the polycondensation reaction.

  Al, Ti, Zr, Mn, Ta, Zn, Cr, Fe, Cd, Co, Ni, Sn, Pb, Sb, Bi, Cu as metal compounds containing metal elements having a standard redox potential of −1.70 V or more And compounds containing a metal element such as Hg, Ag, Pd, Ir, Pt, Au, etc., but from the viewpoint of transparency, it is a compound of Cu, Ag, Pd, Pt, Au, Fe, Zn preferable.

  Further, the metal compound providing the metal element having a standard redox potential of −1.70 V or more does not matter in the addition aspect, the form and the form in the polyester composition. For example, acetates containing the above metal elements, aliphatic carboxylates such as propionate, aromatic carboxylates such as benzoate, nitrates, nitrites, sulfates, sulfites, phosphates, iodides, A bromide, a halide such as chloride, a hydroxide, an oxide, a methylate, an ethylate, ethylene glycolate and the like can be mentioned, and two or more of these can be used in combination. Among these, from the viewpoint of excellent transparency, the use of metal acetates is particularly preferable.

  As a basic compound, although the addition aspect, the form, and the form in polyester composition are not ask | required, it is preferable that it is a metal hydroxide, and it is more preferable that it is an alkali metal hydroxide. When an alkali metal hydroxide is used, a polyester composition having more excellent color tone can be obtained. Among them, potassium hydroxide and sodium hydroxide are particularly preferred. When potassium hydroxide and sodium hydroxide are used, a polyester resin composition which is particularly excellent in thermal oxidative degradation is obtained.

  By making B2 / M3 into said numerical range, the processability and heat-resistant oxidative degradation property of the polyester resin composition obtained become more favorable. The lower limit of B2 / M3 is more preferably 0.1 or more, and still more preferably 0.5 or more. The upper limit of B2 / M3 is more preferably 10 or less, and still more preferably 7 or less.

  In the method for producing a polyester resin composition of the present invention, it is preferable to add a Cu compound containing Cu element at 0.01 mol / t or more and 30 mol / t or less. By adding the Cu compound at the lower limit or more, the thermal oxidation degradation can be improved. By adding the Cu compound at the upper limit or less, generation of foreign matter due to aggregation of the Cu compound can be suppressed and transparency can be improved. The lower limit of the addition amount of the Cu compound is more preferably 0.5 mol / t or more, and the upper limit is more preferably 5 mol / t or less.

  In the method for producing a polyester resin composition of the present invention, when the metal compound containing a metal element having a standard oxidation reduction potential of -1.70 V or more is a Cu compound, the addition amount M4 (mol / t) of the Cu compound and the base It is preferable that ratio B2 / M4 of addition amount B2 (mol / t) of the organic compound is 0.01 or more and 30 or less. The thermal oxidative degradation of the polyester resin composition to which the Cu compound is added is excellent, but coexistence of the Cu compound and the basic compound is preferable in that coexistence of foreign matter aggregation suppression and oxidation degradation resistance of Cu can be achieved.

  By adding B2 / M4 within the above numerical range, the processability and the oxidation degradation resistance of the obtained polyester resin composition become better. The lower limit of B2 / M4 is more preferably 0.1 or more, and still more preferably 0.5 or more. The upper limit of B2 / M4 is more preferably 15 or less, and still more preferably 7 or less.

  In the method for producing a polyester resin composition of the present invention, the basic compound is preferably added as a solution in a solvent, and more preferably in the form of an ethylene glycol solution of the basic compound. In the presence of the basic compound, ethylene glycol dehydrates to form a reducing aldehyde. At this time, the metal ion becomes metal fine particles by the reaction of the metal ion derived from the metal compound used in combination with the aldehyde, and the coloring problem due to the metal ion is improved. By dissolving in a solvent, metal microparticles can be formed uniformly.

  In the method for producing a polyester composition of the present invention, it is preferable to mix and add a solution of a metal compound containing a metal element having a standard redox potential of -1.70 V or more and a basic compound. By mixing and adding, a polyester resin composition having a better color tone can be obtained.

  The solvent may be water or glycol which is a raw material of polyester, but the same glycol as the raw material of polyester is preferable in terms of handleability, quality of obtained polyester, etc. For example, ethylene terephthalate is used for polyethylene terephthalate. It is preferred to use.

  It is preferable to stir the inside of the reaction system at the time of addition of the metal compound and basic compound containing a metal element whose standard oxidation reduction potential is -1.70 V or more and after addition. By stirring, the additive can be dispersed more uniformly, and the transparency can be improved.

  In the method for producing a polyester resin composition of the present invention, it is preferable to add a phenolic antioxidant in that the heat resistant oxidative degradation can be further enhanced. In addition, by adding a metal element and a basic compound having a standard redox potential of −1.70 V or more, or a Cu element in combination with a phenolic antioxidant, the heat oxidation and oxidation degradation is further improved. it can.

  In the method for producing a polyester resin composition of the present invention, it is preferable to add an antistatic agent in an amount of 0.1 wt% or more and 20 wt% or less. As a method of adding an antistatic agent to the polyester resin, a method of adding it in any step of the (A) esterification reaction or (B) transesterification reaction step and the subsequent (C) polycondensation reaction step, Further, a method of melt-kneading a polyester resin and an antistatic agent, a method of melt-kneading a polyester resin and an antistatic agent master, a method of applying an antistatic agent to the surface of the polyester resin, and the like can be mentioned. As a method of adding at any stage of the above-mentioned (A) esterification reaction or (B) transesterification reaction step and subsequent (C) polycondensation reaction step, it may be added at any stage, From the viewpoint that the dispersibility of the antistatic agent is improved and the antistatic performance is improved, it is preferable to be added in the second step of (C) polycondensation reaction.

  In the method for producing a polyester resin composition of the present invention, as the antistatic agent, known ones can be used. For example, anionic surfactant, cationic surfactant, amphoteric surfactant, ionic liquid, A conductive polymer etc. are mentioned. Among them, anionic surfactants are more preferable from the viewpoint of heat resistance and transparency of the polyester resin composition. Also, two or more antistatic agents may be added in combination. The type of surfactant is as described above.

  The addition amount of the antistatic agent may be in a range that does not impair the effects of the present invention, and although depending on the performance of the antistatic agent, it is preferable to be 0.1 wt% or more and 20 wt% or less. More preferably, it is 0.5 wt% or more and 10 wt% or less.

  As a phenol type antioxidant used by the manufacturing method of the polyester resin composition of this invention, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (manufactured by BASF, Irganox 1010) And 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid (manufactured by Sun Chemical Co., Ltd., sianox CY1790), among which Irganox 1010 is color-inhibited and heat-resistant. It is preferable because the oxidative degradability is good. The addition amount of the antioxidant is preferably 0.01 wt% or more and 1.0 wt% or less. When the addition amount is in the above-mentioned range, the thermal oxidative decomposability and the processability can be improved, and the coloring by the antioxidant and the generation of foreign matter can be suppressed.

  In order to sufficiently achieve the effects of the present invention, it is preferable to add a phenolic antioxidant from the end of (A) esterification reaction or (B) transesterification to the end of (C) polycondensation reaction. By adding in the said range, the deactivation of the antioxidant in the manufacturing process of a polyester resin composition can be suppressed, and the thermal oxidative decomposition can be effectively suppressed by the dispersibility in a polyester resin becoming favorable.

  In the method for producing a polyester resin composition of the present invention, solid phase polymerization may be performed to obtain a high molecular weight polyester composition. The solid phase polymerization is carried out by heat-treating the polyester composition under an inert gas atmosphere or under reduced pressure, though the apparatus and method are not particularly limited. The inert gas may be any inert gas to the polyester composition, and examples thereof include nitrogen, helium and carbon dioxide gas, but nitrogen is preferably used in view of economy. Further, under reduced pressure conditions, it is advantageous to set a higher vacuum because the time required for the solid phase polymerization reaction can be shortened, and specifically, it is preferable to keep 110 Pa or less.

  The polyester composition obtained by the present invention can be molded by a known molding method, and can be processed into various products such as films, fibers, bottles, and injection molded products.

  In processing the polyester composition of the present invention into each product, various additives, for example, colorants including pigments and dyes, lubricants, flame retardants, UV absorbers, antibacterial agents, as long as the effects of the present invention are not impaired. One or more additives such as a nucleating agent, a plasticizer, and a mold release agent can also be added.

  The polyester composition of the present invention can be used as a film, a fiber, a bottle, an injection molded product, etc., taking advantage of its excellent resistance to thermal oxidative degradation and processability. It can be preferably used for applications. The method for producing the film is not particularly limited in the apparatus and method. For example, the polyester resin composition obtained in the present invention is melt-extruded in a conventional extruder and T-die to form a film, and then biaxially stretched. The desired stretched film can be obtained by In addition, two or more layers can be provided during melt extrusion, and by providing the polyester resin composition obtained in the present invention on the surface layer of at least one side, the heat-resistant oxidative degradation of the laminated film can be efficiently obtained. Because it is preferable. In addition, when it is set as the said laminated | multilayer film, evaluation of each physical property or an effect is performed by scraping the polyester resin composition of an applicable layer.

  Molded articles produced from the polyester resin composition of the present invention are excellent in heat-resistant oxidative degradability and processability, and therefore, they are agricultural materials, horticultural materials, fishery materials, civil engineering / building materials, stationery, medical supplies, automobiles It is useful as components, electrical / electronic components or other applications.

Hereinafter, the present invention will be more specifically described by way of examples.
In addition, the measuring method of physical properties and the evaluation method of the effect were performed according to the following method.

(1) Intrinsic viscosity of polyester resin composition (unit: dl / g)
It measured at 25 degreeC using the ortho chloro phenol solvent.

(2) Determination of metal elements in polyester composition (Sb, Cu, Zn, Ag elements and alkali metal elements, etc., unit: mol / t)
Quantitative determination was performed by atomic absorption spectrometry using a polarizing Zeeman atomic absorption spectrophotometer 180-80 (frame: acetylene-air) manufactured by Hitachi, Ltd.

(3) Compositional analysis of polyester resin composition (content of polyalkylene glycol (PAG) and number average molecular weight (Mn), content of antistatic agent, content of phenolic antioxidant)
A polyester resin sample is dissolved in heavy hexafluoroisopropanol solvent, and ¹ H-NMR observation is carried out with an H-NMR measuring instrument (GSX-400) manufactured by Nippon Denshi Co., Ltd. Each peak is attributed, and the integration ratio The content (wt%) of the alkylene glycol component and its number average molecular weight, the content (wt%) of the antistatic agent, and the content (wt%) of the phenolic antioxidant were determined.

(4) Dynamic viscoelasticity measurement (complex visco elastic modulus, change rate)
The pellet-like polyester resin composition was dried with a vacuum dryer at 130 ° C. for 15 hours, and dynamic viscoelasticity measurement was performed with a rheometer under the following conditions.
Plate: Parallel plate (20 mm diameter)
Measurement frequency: 0.1 Hz, 0.2 Hz, 0.5 Hz, 1 Hz, 2 Hz, 5 Hz, 10 Hz, 5 Hz, 2 Hz, 1 Hz, 0.5 Hz, 0.2 Hz, 0.1 Hz, 13 points Measurement device: ( UBM Co., Ltd. "RHEOSOL-G3000"
・ Measurement temperature: 280 ° C
Measurement environment: Sufficient fluidity when the value of the complex viscosity ** 1 at angular velocity ω = 1.25 rad / sec (measurement frequency 0.2 Hz) under nitrogen atmosphere is 100 Pa · sec or more and 400 Pa · sec or less It was judged that the processability was good because it was easy to handle.

Also, assuming that the complex viscosity at an angular velocity ω = 62.83 rad / sec (measurement frequency 10 Hz) is ** 2, the rate of change of the complex visco elastic modulus is calculated by the equation (3). It was judged that the rate of change was small when it was below, and the rate of change was large when it exceeded 0.2.
Rate of change = (. Eta. * 1-.eta. * 2) /. Eta. * 2 (3).

(5) Thermal oxidative degradation (TGA / PAG)
Measure 5 mg of the polyester resin composition vacuum-dried for 12 hours at 130 ° C. for 12 hours, and use a differential thermal thermal simultaneous measurement device (TG / DTA 6200) manufactured by Seiko Instruments Inc. under a flow of dry air of 20% oxygen concentration (flow 200 mL Temperature from room temperature to 280 ° C. and held at 280 ° C., measured for weight loss rate (wt%) for 60 minutes after reaching 280 ° C. and Example (3) The PAG decomposition rate was calculated by Formula (1) using the obtained PAG.
PAG decomposition rate = TGA / PAG (1)
When this decomposition rate was 0.4 or less, it was judged that the thermal oxidative decomposability was good.

(6) Transparency 7 g of the polyester resin composition vacuum-dried for 12 hours at 130 ° C. is sandwiched between smooth plates and melted at 270 ° C. for 60 seconds, then pressed at 270 ° C. 1.5 MPa for 5 seconds, submerged in a water bath and cooled The sheet | seat of length 120 mm x width 120 mm x thickness 0.4 mm was produced by doing. The appearance of the obtained sheet was observed and judged.
A: It is transparent without turbidity.
B: Turbid but clear.
C: It is opaque.

Example 1
101 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol (1.9 times mole of dicarboxylic acid component), 0.07 parts by weight of manganese acetate tetrahydrate, 0.0084 parts by weight of diantimony trioxide The contents were dissolved at 150 ° C. Thereafter, methanol was distilled while raising the temperature to 240.degree. After methanol equivalent to 95% of the reaction rate is distilled off, a mixed solution of 0.07 parts by weight of ethyl diethylphosphonoacetate / 1.4 parts by weight of ethylene glycol is added, and after stirring for 5 minutes, ammonium dodecylbenzenesulfonate 1 A mixed solution of 1 part by weight / 4 parts by weight of ethylene glycol was added and stirred for 25 minutes to complete transesterification.

Thereafter, the reaction product is charged in a polymerization apparatus, 2.06 parts by weight of polyethylene glycol (molecular weight 4000) and 0.1 parts by weight of Irganox 1010 (manufactured by BASF) are added, and after stirring for 5 minutes, copper acetate (II) monohydrate A mixed solution of 0.005 parts by weight (equivalent to 0.25 mol / t) /0.016 parts by weight of potassium hydroxide / 0.4 parts by weight of ethylene glycol was added and stirred for 5 minutes. Thereafter, while raising the temperature in the polymerization apparatus to 290 ° C., the pressure in the polymerization apparatus was gradually reduced from normal pressure to vacuum to distill ethylene glycol off. The reaction is terminated when the melt viscosity reaches an intrinsic viscosity of 0.6, and the inside of the reaction system is brought to normal pressure with nitrogen gas, discharged from the lower part of the polymerization apparatus into strands in cold water, and cut. A resin composition was obtained. The properties of the obtained polyester resin composition are shown in Table 2.
The polyester resin composition obtained in Example 1 had good thermal oxidative degradation and processability. In addition, the rate of change of the complex visco modulus was small and the press sheet was transparent.

(Examples 2-4, comparative examples 1-2)
A polyester resin composition was obtained in the same manner as Example 1, except that the amount of polyethylene glycol added was changed as shown in Table 1. The properties of the obtained polyester resin composition are shown in Table 2.

  The polyester resin compositions obtained in Examples 2 and 3 had good resistance to thermal oxidative decomposability and processability, and the change rate of the complex visco modulus was small, and the press sheet was transparent.

  The polyester resin composition obtained in Example 4 had good resistance to thermal oxidative decomposability and processability, a small rate of change in the complex visco modulus, and although the haze was observed in the press sheet, it was transparent.

  Since the polyester resin composition obtained in Comparative Example 1 did not contain a polyalkylene glycol, the melt viscoelastic modulus η * 1 was high, and the processability was reduced.

  Since the polyester resin composition obtained in Comparative Example 2 contains a polyalkylene glycol in excess of 20 wt%, the thermal oxidative degradation property is reduced, the melt viscosity 粘 * 1 is low, and the processability is It fell, and the stable strand was not obtained at the time of discharge from a polymerization apparatus.

(Examples 5 to 8)
A polyester resin composition was obtained in the same manner as in Example 1 except that the compound used as the polyalkylene glycol was changed as shown in Table 1. The properties of the obtained polyester resin composition are shown in Table 2.

  The polyester resin compositions obtained in Examples 5 and 6 had good resistance to thermal oxidative decomposability and processability, and the rate of change in complex visco modulus was small, and the press sheet was transparent.

  The polyester resin composition obtained in Example 7 has good resistance to thermal oxidative decomposability and processability, but has a large rate of change in the complex visco modulus, so that some strand disorder occurs at the time of discharge from the polymerization apparatus. There was no problem at this level, and the press sheet was clear but transparent.

  The polyester resin composition obtained in Example 8 has good resistance to thermal oxidative decomposability and processability, but has a large rate of change in the complex visco modulus, so that some strand disorder occurs at the time of discharge from the polymerization apparatus. There was no problem and the press sheet was opaque.

(Examples 9 to 11, Comparative Example 3)
A polyester resin composition was obtained in the same manner as in Example 1 except that the metal compound to be added was not changed or added as shown in Table 1. The properties of the obtained polyester resin composition are shown in Table 3.

  The polyester resin composition obtained in Example 9 had good resistance to thermal oxidative degradation and processability, and the change rate of the complex visco modulus was small, and the press sheet was transparent.

  The polyester resin compositions obtained in Examples 10 and 11 had good resistance to thermal oxidative decomposability and processability, a small rate of change in complex visco modulus, and although transparency was observed in the pressed sheet, they were transparent. .

  The polyester resin composition obtained in Comparative Example 3 was insufficient in thermal oxidative degradation, and many bubbles were observed in the press sheet due to the decomposition gas.

(Examples 12 to 19)
A polyester resin composition was obtained in the same manner as in Example 1 except that the addition amount of the metal compound and / or the basic compound to be added was changed as shown in Table 1. The properties of the obtained polyester resin composition are shown in Table 3.

  The polyester resin compositions obtained in Examples 12 and 13 had good resistance to thermal oxidative decomposability and processability, and the change rate of the complex visco modulus was small, and the press sheet was transparent.

  The polyester resin compositions obtained in Examples 14, 15, 17, 18 had good resistance to thermal oxidative decomposability and processability, a small rate of change in complex visco modulus, and turbidity was observed in the pressed sheet. It was transparent.

  The polyester resin compositions obtained in Examples 16 and 19 had good resistance to thermal oxidative degradation and processability, and the change rate of the complex visco modulus was small, but aggregation due to the additive metal compound and the basic compound The press sheet was opaque due to foreign matter and coloring.

Example 20
A polyester resin composition was obtained in the same manner as in Example 1 except that the basic compound to be added was changed as shown in Table 1. The properties of the obtained polyester resin composition are shown in Table 3.
The polyester resin composition obtained in Example 20 had good thermal oxidative degradation and processability. In addition, the rate of change of the complex visco modulus was small and the press sheet was transparent.

Claims (7)

A polyester resin composition containing 0.1 to 20 wt% of polyalkylene glycol, which satisfies the formula 1.
TGA / PAG ≦ 0.4 (1)
Here, TGA is a thermal weight reduction rate (unit wt%) in dry air circulation at 280 ° C. for 60 minutes, and PAG is a content of polyalkylene glycol (unit wt%). The polyester resin composition according to claim 1, characterized in that it contains the metal element having a standard redox potential of -1.70 V or more and the alkali metal element, and the formula 2 is satisfied.
0.01 ≦ B / M ≦ 30 (2)
Here, M is the content (unit mol / t) of the metal element having a standard redox potential of −1.70 V or more, and B is the content (unit mol / t) of the alkali metal element.   The polyester resin composition according to claim 1 or claim 2, which contains 0.01 to 30 mol / t of Cu element.   The polyester resin composition according to any one of claims 1 to 3, wherein the polyalkylene glycol is polyethylene glycol.   The polyester resin composition according to any one of claims 1 to 4, wherein the antistatic agent is contained in an amount of 0.1 wt% or more and 20 wt% or less.   The polyester resin composition according to claim 5, wherein the antistatic agent is an anionic antistatic agent.   The polyester resin composition according to any one of claims 1 to 6, which contains a phenolic antioxidant.