JP2007169368A - Flame-retardant polyester resin composition and polyester resin structure - Google Patents

Abstract

【Task】
Provided is a flame retardant polyester resin composition having excellent mechanical properties, molding processability (fluidity), hydrolysis resistance, and high flame retardancy.
[Solution]
(A) 1 to 99 parts by weight of the aromatic polyester resin and (B) 1 to 99 parts by weight of the aliphatic polyester copolymer, and 100 parts by weight of (C) 3 to 50 parts by weight of the brominated flame retardant And (D) a flame retardant polyester resin composition containing 1 to 30 parts by weight of an antimony compound, wherein the terminal carboxyl group concentration of the (A) aromatic polyester resin is 50 eq / ton or less, B) The aliphatic polyester copolymer contains 0 to 30 mol% of aliphatic oxycarboxylic acid units, 35 to 50 mol% of aliphatic and / or alicyclic diol units, and 35 to 50 aliphatic dicarboxylic acid units. A flame-retardant polyester resin composition containing mol%, and further a polyester resin structure formed by molding the resin composition.
[Selection figure] None

Description

  The present invention relates to a flame retardant polyester resin composition and a polyester resin structure, and more specifically, has excellent mechanical properties, molding processability, hydrolysis resistance, and high flame retardancy. The present invention relates to a flame-retardant polyester resin composition suitable as a material for parts such as electronic devices and machines, and a polyester resin structure formed by molding the resin composition.

  Aromatic polyester resins as engineering plastics, especially polybutylene terephthalate resins, are superior in mechanical strength, heat resistance, chemical resistance, and other physical and chemical properties. It is widely used as a material for various parts in the field of precision equipment. As the application field of aromatic polyester resins expands, further improvements in toughness and impact resistance are required, and molding processability (fluidity) is increasing as the moldings become thinner and larger in recent years. There has been a strong demand for improvements. In order to satisfy these requirements, various resin compositions in which an aliphatic polyester resin is blended with an aromatic polyester resin have been proposed.

For example, in Patent Documents 1 and 2, a resin composition containing a thermoplastic aromatic polyester and a thermoplastic soft polyester having a specific glass transition point and heat of crystal melting has excellent taste preservation and impact resistance. It is disclosed that an excellent packaging material can be obtained.
Patent Document 3 discloses a resin composition comprising a polymer having an aliphatic ester structure and an aromatic group-containing polyester resin. In particular, an aliphatic polyester polycarbonate resin is used as the polymer having an aliphatic ester structure. It is described that a resin composition that exhibits biodegradability and has high tear strength can be obtained by use.

Furthermore, Patent Document 4 discloses that a resin composition obtained by adding a specific amount of a condensed polymer having an aromatic ring to an aliphatic polyester has improved crystallization speed and excellent strand cutting properties. Yes.
However, the resin compositions described in Patent Documents 1 to 4 are still insufficient in terms of mechanical properties, molding processability (fluidity), hydrolysis resistance, and physical properties of aromatic polyester, such as No attention has been paid to the influence of the terminal carboxyl group concentration on these properties.

In addition, flame retardance is required for resins used for electrical / electronic parts, electrical parts such as automobile parts, and machine parts. In recent years, these parts have been reduced in thickness and size due to the trend of downsizing and weight reduction of various devices. In such a thin molded product, severe flame retardancy is often required for the thinnest part, and the flame retardancy of rank V-0 defined in UL-94 is used as an index.
Accordingly, it has been desired to develop a reinforced polyester resin composition having excellent mechanical properties, molding processability (fluidity), hydrolysis resistance, flame retardancy, and overall excellent performance.
JP 2000-129104 A JP 2000-129106 A JP 2004-18842 A JP 2005-133003 A

The present invention has been made in view of such circumstances, and its purpose is excellent in mechanical properties, molding processability (fluidity), hydrolysis resistance, and flame retardancy having high flame retardancy. The object is to provide a polyester resin composition.

  As a result of intensive studies, the present inventors have found that the terminal carboxyl group concentration of the aromatic polyester resin affects each of the above-described properties for the resin composition containing the aromatic polyester resin and the aliphatic polyester copolymer. I found out. Then, using an aromatic polyester resin having a terminal carboxyl group concentration of a specific value or less and knowing that the above object can be achieved by including a brominated flame retardant and an antimony compound, the present invention has been achieved. .

That is, the first gist of the present invention is that (A) 1 to 99 parts by weight of an aromatic polyester resin and (B) 1 to 99 parts by weight of an aliphatic polyester copolymer are combined with (C A flame retardant polyester resin composition containing 3 to 50 parts by weight of a brominated flame retardant and 1 to 30 parts by weight of (D) an antimony compound, the terminal carboxyl group of the aromatic polyester resin (A) The concentration is 50 eq / ton or less, and the (B) aliphatic polyester copolymer represents 0 to 30 mol% of an aliphatic oxycarboxylic acid unit represented by the following formula (I) and represented by the following formula (II). A flame-retardant polyester comprising 35 to 50 mol% of an aliphatic and / or alicyclic diol unit and 35 to 50 mol% of an aliphatic dicarboxylic acid unit represented by the following formula (III): Resin composition That.

  Moreover, the 2nd summary of this invention exists in the polyester resin structure characterized by shape | molding the flame-retardant polyester resin composition of said 1st summary.

  The flame-retardant polyester resin composition of the present invention has improved mechanical properties, particularly impact resistance, and is excellent in moldability (fluidity), hydrolysis resistance and flame retardancy, and is well balanced. Therefore, it is expected as an engineering plastic material for various structures.

  In particular, it is expected to be used as various structural materials that require impact resistance. Specifically, aircraft, rockets, artificial satellites and other aircraft and spacecraft, railways, boats, automobiles, motorcycles, bicycles, etc. Structural materials, outer panels, pressure members for transport equipment, and casings and internal precision parts for electrical and electronic equipment; suitable for various office supplies such as writing utensils, desks and chairs, and daily necessities including various resin structures I can do it.

  Hereinafter, the present invention will be described in detail. However, the description of the constituent elements described below is a representative example of embodiments of the present invention, and the present invention is not limited to these contents.

(A) Aromatic polyester resin First, the (A) aromatic polyester resin used in the present invention will be described. The aromatic polyester resin is a polycondensate of an aromatic dicarboxylic acid or a derivative thereof and a diol. As the raw material aromatic dicarboxylic acid or derivative thereof, terephthalic acid or its lower alkyl ester is mainly used, but phthalic acid, isophthalic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenylether dicarboxylic acid. 4,4′-benzophenone dicarboxylic acid, 4,4′-diphenoxyethanedicarboxylic acid, 4,4′-diphenylsulfone dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, or a lower alkyl ester thereof, or one or two of them You may use the above together.

Examples of the diol to be reacted with the aromatic dicarboxylic acid or its derivative include ethylene glycol, 1,4-butanediol, polyethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, polypropylene glycol, polytetra Methylene glycol, dibutylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, aliphatic diols such as 1,8-octanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol , 1,1-cyclohexanedimethylol, 1,4-cyclohexanedimethylol and other alicyclic diols, xylylene glycol, 4,4′-dihydroxybiphenyl, 2,2-bis (4-hydroxyphenyl) propane, bis ( 4 Aromatic diols such as -hydroxyphenyl) sulfone are mentioned, and ethylene glycol or 1,4-butanediol is preferred.

  Furthermore, as a part of the dicarboxylic acid and diol, hydroxy such as lactic acid, glycolic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 6-hydroxy-2-naphthalenecarboxylic acid, p-β-hydroxyethoxybenzoic acid, etc. Monofunctional components such as carboxylic acid, alkoxycarboxylic acid, stearyl alcohol, benzyl alcohol, stearic acid, benzoic acid, t-butylbenzoic acid, benzoylbenzoic acid, tricarbaric acid, trimellitic acid, trimesic acid, pyromellitic acid, Trifunctional or higher polyfunctional components such as gallic acid, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol and the like can be used.

  The aromatic polyester resin (A) used in the present invention is preferably a polyethylene terephthalate resin (hereinafter sometimes referred to as PET resin) or a polybutylene terephthalate resin (hereinafter sometimes referred to as PBT resin). A PBT resin having moderate mechanical strength is most preferable. Here, the PBT resin is a component (terephthalic acid component) in which 50% by weight or more of all dicarboxylic acid components are derived from terephthalic acid or a derivative thereof, and 50% by weight or more of all diol components are converted to 1,4-butanediol. Polyesters composed of derived components are preferred. Among them, the ratio of the terephthalic acid component to the total dicarboxylic acid component is preferably 80 mol% or more, and more preferably 95 mol% or more. Moreover, 80 mol% or more is preferable and, as for the ratio of the 1, 4- butanediol component with respect to all the diol components, 95 mol% or more is more preferable.

The present invention is characterized in that the terminal carboxyl group concentration of (A) the aromatic polyester resin, particularly the PBT resin, is 50 eq / ton or less. Thereby, compatibility with (A) aromatic polyester resin and (B) aliphatic polyester copolymer, which will be described later, can be moderately increased, the hydrolysis resistance of the resin composition is remarkably enhanced, and molding residence stability is also improved. In addition, the heat aging stability can be improved. The terminal carboxyl group concentration is preferably 38 eq / ton or less, more preferably 30 eq / ton or less, and particularly preferably 25 eq / ton or less. The terminal carboxyl group concentration can be determined by dissolving (A) the aromatic polyester resin in an organic solvent and titrating with an alkali hydroxide solution.

  In the aromatic polyester resin (A) of the present invention, the content of the titanium compound is usually 300 ppm (weight ratio) or less in terms of titanium atoms, among which 150 ppm or less, more preferably 70 ppm or less, and particularly 40 ppm or less. preferable. On the other hand, the lower limit is 10 ppm or more, preferably 12 ppm or more, more preferably 15 ppm or more, and particularly preferably 20 ppm or more. If the content exceeds 300 ppm, the residence thermal stability and hydrolysis resistance of the resin composition may be reduced, or transesterification with the aliphatic polyester copolymer may proceed. The metal content of the titanium atom can be measured using a method such as atomic emission, atomic absorption, Inductively Coupled Plasma (ICP) after recovering the metal in the polymer by a method such as wet ashing. The titanium compound is usually mixed in the resin by leaving the catalyst used in the process of producing the (A) aromatic polyester resin. Therefore, the amount of titanium compound in the resin can be adjusted by adjusting the amount of titanium catalyst used.

The intrinsic viscosity of the PBT resin was measured using a mixed solvent of 1,1,2,2-tetrachloroethane / phenol = 1/1 (weight cost) at a solution concentration of 0.5 g / dl at 30 ° C. Usually, it is 0.5-3 dl / g, Preferably it is 0.6-2 dl / g, More preferably, it is the range of 0.7-1.5 dl / g. If the intrinsic viscosity is less than 0.5 dl / g, the mechanical strength may be insufficient. On the other hand, if the intrinsic viscosity is greater than 3 dl / g, molding may be difficult.
Moreover, the intrinsic viscosity of PET resin is 0.4-3 dl / g normally, Preferably it is 0.5-1.5 dl / g, More preferably, it is the range of 0.6-1.0 dl / g. In addition, you may adjust so that an intrinsic viscosity may become the said range by using together 2 or more types of PBT resin and PET resin from which intrinsic viscosity differs.

  Furthermore, (A) the amount of residual tetrahydrofuran in the aromatic polyester resin, particularly PBT resin, is usually 800 ppm (weight ratio) or less, but 300 ppm (weight ratio) or less, more preferably 250 ppm (weight ratio) or less, 200 ppm or less is preferable. The amount of the remaining tetrahydrofuran can be determined by immersing the resin pellet in water and treating it at 120 ° C. for 6 hours, and quantifying the amount of tetrahydrofuran eluted in water by gas chromatography. By setting the residual tetrahydrofuran amount to 300 ppm (weight ratio) or less, even when a molded product obtained from the resin composition of the present invention is used at a high temperature, the generation of gas such as tetrahydrofuran is small, and corrosion of electrical contacts is caused. Therefore, it can be suitably used for electrical / electronic components having electrical contacts such as relay components.

  The lower limit of the residual tetrahydrofuran amount is not particularly limited, but is usually about 50 ppm (weight ratio). A smaller amount of residual tetrahydrofuran tends to reduce the generation of organic gas, but the remaining amount and the amount of gas generated are not necessarily proportional. Further, as described in JP-A-8-209004, the presence of a small amount of tetrahydrofuran is also expected to suppress the corrosion of electrical contacts.

  The (A) aromatic polyester resin having a low terminal carboxyl group concentration used in the present invention may be either a method of melt polymerizing an aromatic dicarboxylic acid or a derivative thereof and a diol, or a method of further solid-phase polymerization after a melt polymerization reaction. It can be produced, and may be either a continuous process or a batch process. Among these methods, the melt polymerization method by the continuous method in which the raw material supply, the esterification reaction, and the subsequent polycondensation reaction are continuously produced more easily produces an aromatic polyester resin having a low terminal carboxyl group concentration. It is preferable in that it can be performed.

  As the melt polymerization method by a continuous method, for example, a dicarboxylic acid component and a diol component are preferably used at 150 to 280 ° C., more preferably in the presence of an esterification reaction catalyst in one or a plurality of esterification reaction vessels. Is a continuous esterification reaction at a temperature of 180 to 265 ° C., preferably 6.67 to 133 kPa, more preferably 9.33 to 105 kPa, with stirring for 2 to 5 hours. Subsequently, the oligomer which is the obtained esterification reaction product is transferred to a polycondensation reaction tank, and preferably in the presence of a polycondensation reaction catalyst in one or a plurality of polycondensation reaction tanks, preferably 210 to 280 ° C. The polycondensation reaction can be carried out continuously for 2 to 5 hours with stirring under a reduced pressure of 220 to 265 ° C., preferably 26.7 kPa or less, more preferably 20 kPa or less. The aromatic polyester resin such as PBT resin obtained by the polycondensation reaction is transferred from the bottom of the polycondensation reaction tank to a polymer extraction die and extracted in the form of a strand, while being cooled with water or after being cooled with water, using a pelletizer. Cut into pellets.

  The (A) aromatic polyester resin having a low terminal carboxyl group concentration used in the present invention can also be produced by performing solid phase polymerization after melt polymerization. For example, it can also be produced by melt polymerization such as batch method, transesterification, or esterification and polycondensation to obtain a polyester resin having a relatively high intrinsic viscosity, followed by solid phase polymerization. It is.

  (A) In the esterification reaction in the production of an aromatic polyester resin, for example, an esterification reaction catalyst such as a titanium compound, a tin compound, a magnesium compound, or a calcium compound can be used, and among these, a titanium compound is preferable. Used for. Examples of the titanium compound include titanium alcoholates such as tetramethyl titanate, tetraisopropyl titanate, and tetrabutyl titanate, and titanium phenolates such as tetraphenyl titanate.

  (A) In the polycondensation reaction in the production of the aromatic polyester resin, a polycondensation reaction catalyst such as an antimony compound such as antimony trioxide or a germanium compound such as germanium dioxide or germanium tetroxide can be used. .

  In the esterification reaction and / or polycondensation reaction described above, in addition to the above-described catalyst, orthophosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, or phosphorus compounds such as esters and metal salts thereof, water Reaction aids such as alkali metal or alkaline earth metal compounds such as sodium oxide, sodium benzoate, magnesium acetate, calcium acetate, 2,6-di-t-butyl-4-octylphenol, pentaerythrityl tetrakis [3- Phenol compounds such as (3 ′, 5′-t-butyl-4′-hydroxyphenyl) propionate], dilauryl-3,3′-thiodipropionate, pentaerythrityltetrakis (3-laurylthiodipropionate), etc. Thioether compounds, triphenyl phosphite, tris (nonylphenyl) phosphite, Antioxidants such as phosphorus compounds such as bis (2,4-di-t-butylphenyl) phosphite, paraffin wax, microcrystalline wax, polyethylene wax, long chain fatty acids such as montanic acid and montanic acid ester or esters thereof, A release agent such as silicone oil can be present.

(B) Aliphatic polyester copolymer Next, the (B) aliphatic polyester copolymer used in the present invention will be described. (B) The aliphatic polyester copolymer is a copolymer containing the units represented by the following (I), (II) and (III) in predetermined mol%, and an aliphatic oxy corresponding to each unit. It can be produced by copolymerizing a predetermined amount of carboxylic acid, aliphatic and / or alicyclic diol, and aliphatic dicarboxylic acid. The number average molecular weight of the (B) copolymer is usually 10,000-2.
0,000, preferably 30,000 to 100,000.

The aliphatic oxycarboxylic acid unit of the above formula (I) has one hydroxyl group and carboxyl group in the molecule represented by HO—R ¹ —COOH (R ¹ represents a divalent aliphatic hydrocarbon group). It can be obtained by using an aliphatic oxycarboxylic acid having a derivative thereof or a derivative thereof (cyclic monomer, cyclic dimer, anhydride, ester, etc.). As the aliphatic oxycarboxylic acid, preferably, R ¹ is a divalent alkylidene group having 1 to 20 carbon atoms or an alkylene group, and further α-oxy represented by the following formula (I-1): Carboxylic acid is preferred.

（式中、ｎは０又は１〜１０の整数を示す。）
式（Ｉ−１）中のｎは、０又は１〜１０の整数であり、好ましくは０又は１〜５の整数である。式（Ｉ−１）のオキシカルボン酸の具体例としては、グリコール酸、Ｌ−乳酸、Ｄ−乳酸、Ｄ，Ｌ−乳酸、２−ヒドロキシ−ｎ−酪酸、２−ヒドロキシ−３−メチル−ｎ−酪酸、２−ヒドロキシ−３，３−ジメチル−ｎ−酪酸、３−ヒドロキシ−ｎ−酪酸、４−ヒドロキシ−ｎ−酪酸、２−ヒドロキシ−ｎ−吉草酸、３−ヒドロキシ−ｎ−吉草酸、４−ヒドロキシ−ｎ−吉草酸、５−ヒドロキシ−ｎ−吉草酸、２−ヒドロキシ−ｎ−カプロン酸、２−ヒドロキシ−ｉ−カプロン酸、３−ヒドロキシ−ｎ−カプロン酸、４−ヒドロキシ−ｎ−カプロン酸、５−ヒドロキシ−ｎ−カプロン酸、６−ヒドロキシ−ｎ−カプロン酸等が挙げられる。また、オキシカルボン酸の誘導体としては、例えば、プロピオラクトン、ブチロラクトン、バレロラクトン、カプロラクトン、ラウロラクトン等のラクトン類が挙げられる。これらのオキシカルボン酸の中で好ましいのは乳酸またはグリコール酸であり、特に好ましいのは乳酸である。乳酸は、ポリエステル共重合体製造時の重合速度の増大が特に顕著であり、また、入手が容易である。乳酸は、通常３０〜９５重量％の水溶液の形態で入手し得る。

(In the formula, n represents 0 or an integer of 1 to 10.)
N in the formula (I-1) is 0 or an integer of 1 to 10, preferably 0 or an integer of 1 to 5. Specific examples of the oxycarboxylic acid of the formula (I-1) include glycolic acid, L-lactic acid, D-lactic acid, D, L-lactic acid, 2-hydroxy-n-butyric acid, 2-hydroxy-3-methyl-n. -Butyric acid, 2-hydroxy-3,3-dimethyl-n-butyric acid, 3-hydroxy-n-butyric acid, 4-hydroxy-n-butyric acid, 2-hydroxy-n-valeric acid, 3-hydroxy-n-valeric acid 4-hydroxy-n-valeric acid, 5-hydroxy-n-valeric acid, 2-hydroxy-n-caproic acid, 2-hydroxy-i-caproic acid, 3-hydroxy-n-caproic acid, 4-hydroxy- Examples include n-caproic acid, 5-hydroxy-n-caproic acid, and 6-hydroxy-n-caproic acid. Examples of the oxycarboxylic acid derivative include lactones such as propiolactone, butyrolactone, valerolactone, caprolactone, and laurolactone. Of these oxycarboxylic acids, preferred is lactic acid or glycolic acid, and particularly preferred is lactic acid. Lactic acid is particularly prominent in increasing the polymerization rate during the production of the polyester copolymer, and is easily available. Lactic acid is usually available in the form of a 30-95% by weight aqueous solution.

The aliphatic or alicyclic diol corresponding to the diol unit of the formula (II) is a diol represented by HO—R ² —OH (R ² represents a divalent aliphatic or alicyclic hydrocarbon). is there. In the formula (II), the divalent aliphatic hydrocarbon group represented by R ² is preferably a linear alkylene group, and the carbon number thereof is usually 2 to 10, preferably 3 to 10, and more preferably. Is 4-6. Examples of the alicyclic hydrocarbon group represented by R ^2, preferably a cycloalkylene group, the number of carbon is usually 3-10, preferably 4-6.

Specific examples of the aliphatic or alicyclic diol as described above include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,2-butanediol, 1,5-pentanediol, 1, 6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,2 -Cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethylol, 1,4-cyclohexanedimethylol and the like. These can be used as a mixture of two or more, for example, aliphatic diol and alicyclic diol. Among the above diols, ethylene glycol, 1,3-propanediol, and 1,4-butanediol are preferable from the viewpoint of physical properties of the polyester resin composition, and more preferably 1,3-propane. Diols and 1,4-butanediol, particularly 1,4-butanediol are preferred.

The aliphatic dicarboxylic acid corresponding to the aliphatic dicarboxylic acid unit of the formula (III) or a derivative thereof is represented by HOOC-R ³ —COOH (R ³ represents a direct bond or a divalent aliphatic hydrocarbon group). Dicarboxylic acid, its lower alcohol ester or acid anhydride. In the formula, R ³ is preferably a direct bond or a linear alkylene group, and the linear alkylene usually has 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms. As the carboxylic acid, for example, succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecadicarboxylic acid, dodecadicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, dimer acid and hydrogenated product thereof, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid and the like. Examples of the lower alcohol ester of dicarboxylic acid include esters of aliphatic alcohols having about 1 to 4 carbon atoms such as dimethyl ester, diethyl ester, and dibutyl ester. Examples of acid anhydrides include succinic anhydride and anhydrous adipic acid. Etc. These can also be used as a mixture of two or more. Among these, succinic acid and adipic acid are preferable and succinic acid is most preferable from the viewpoint of physical properties of the polyester resin composition.

  Part of the dicarboxylic acid component which is a component of the (B) aliphatic polyester copolymer of the present invention may be copolymerized with an aromatic dicarboxylic acid. In this case, the ratio of the aromatic dicarboxylic acid to the total dicarboxylic acid is preferably 60 mol% or less, more preferably 50 mol% or less, and still more preferably 30 mol% or less.

The ratio of each unit in the aliphatic polyester copolymer used in the present invention is as follows. That is, the unit of the formula (I) is 0 to 30 mol%, and the unit of the formula (II) and (III) is 35 to 50 mol%, preferably 40 to 49.75 mol%, more preferably 45 Although selected from the range of ˜49.5 mol%, the proportions of the units of formula (II) and formula (III) are usually substantially equal. Here, the fact that the proportion of both is substantially equal means that the difference between the proportions of the two is usually within 3 mol%, and further within 2 mol%. When a mixture of an aliphatic diol and an alicyclic diol is used as the diol corresponding to the diol unit of the formula (II), the total content of both may be in the above range.

Further, the unit of the formula (I) is an arbitrary unit, but it is preferable to include it as an essential unit, and the ratio in that case is usually 0.02 to 30 mol%, preferably 0.5 to 20 mol%, More preferably, it is the range of 1-10 mol%. If the number of units of formula (I) is too small, the biodegradability effect of the resulting copolymer will be small, and if it is too large, the crystallinity of the resulting copolymer will be lost and molding will be difficult. It may not be preferable.

The aliphatic polyester copolymer in the present invention is prepared by reacting a diol and a dicarboxylic acid corresponding to the units (II) and (III) or a derivative thereof as described in, for example, JP-A-8-239461. When the aliphatic polyester is produced, the aliphatic oxycarboxylic acid corresponding to the unit of the formula (I) can be produced by a copolymerization method so that the amount is in the above-mentioned predetermined range.

The amount of diol corresponding to formula (II) is substantially equimolar to the dicarboxylic acid or derivative thereof (value based on the amount of dicarboxylic acid) corresponding to formula (III), but it is distilled during the esterification reaction. Therefore, it is usually used in an excess of 1 to 20 mol%. The amount of the aliphatic oxycarboxylic acid corresponding to the formula (I) is the dicarboxylic acid corresponding to the formula (III) or its derivative 10
It is 0-60 mol normally with respect to 0 mol, Preferably it is 0.04-60 mol, More preferably, it is 1-40 mol, Most preferably, it is 2-20 mol.

  The addition time of the aliphatic oxycarboxylic acid is not particularly limited as long as it is before the polycondensation reaction, but a method of adding at the same time as the catalyst at the time of charging the raw material, a method of adding the catalyst by dissolving it in the oxycarboxylic acid solution in advance, etc. are adopted. I can do it.

  (B) It is preferable to use a polymerization catalyst in the production of the aliphatic polyester copolymer. Although it does not specifically limit as a polymerization catalyst, Compounds, such as germanium, titanium, antimony, tin, magnesium, calcium, zinc, are mentioned, Among these, germanium, titanium, zinc compounds are preferable, and germanium compounds such as germanium oxide are particularly preferable. Is preferred.

  The amount of the polymerization catalyst used is generally 0.001% by weight or more, preferably 0.005% by weight or more, and the upper limit is usually 3% by weight or less, based on the total amount of monomers used in the polycondensation reaction. 1.5% by weight or less. The catalyst addition time is not particularly limited as long as it is before the start of the polycondensation reaction, but it is preferably added when the raw materials are charged, and a method of adding the catalyst after dissolving it in an aqueous solution is preferable. Among these, from the viewpoint of storage stability of the catalyst, a method in which the catalyst is dissolved in an aliphatic oxycarboxylic acid and added is preferable.

  (B) The conditions for producing the aliphatic polyester copolymer vary depending on the combination of raw material monomers, the composition ratio, the type and amount of the catalyst, etc., but the lower limit of the temperature is usually 150 ° C. or higher, preferably 180 ° C. The upper limit is usually 260 ° C. or lower, preferably 250 ° C. or lower, more preferably 240 ° C. or lower, particularly preferably 230 ° C. or lower, and the polymerization reaction time is 2 hours or longer, preferably 4 to 15 hours. It is better to choose in the range. The reaction pressure is 10 mmHg or less, preferably 2 mmHg or less.

  (B) The intrinsic viscosity of the aliphatic polyester copolymer is a mixed solvent of 1,1,2,2-tetrachloroethane / phenol = 1/1 (weight ratio), and the solution concentration is 0.5 g / 30 ° C. at 30 ° C. The value measured by dl is usually in the range of 0.5 to 4 dl / g, preferably 0.8 to 3 dl / g, more preferably 1 to 2.5 dl / g. If the intrinsic viscosity is less than 0.5 dl / g, the mechanical strength may be insufficient. On the other hand, if the intrinsic viscosity is greater than 4 dl / g, molding may be difficult.

The content of the (B) aliphatic polyester copolymer in the resin composition of the present invention is not particularly limited, but is usually 1 to 500 parts by weight, preferably 100 parts by weight of the (A) aromatic polyester resin. Is 5 to 300 parts by weight, more preferably 10 to 150 parts by weight, and particularly preferably 15 to 90 parts by weight. When the amount of the (B) copolymer is too small, the biodegradability of the resulting resin composition may be insufficient. On the other hand, when the amount is too large, the impact resistance of the resulting resin composition may be insufficient. In some cases, improvement of mechanical properties such as property is insufficient.

In addition to the structural units (I) to (III), other copolymer components can be introduced into the (B) aliphatic polyester copolymer as long as the effects of the present invention are not impaired. Other raw materials for the copolymerization component include aromatic oxycarboxylic acids such as hydroxybenzoic acid, aromatic diols such as bisphenol A, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, trimethylolpropane, glycerin and the like. And polyhydric oxycarboxylic acids such as monohydric alcohols and malic acid.

(C) Brominated flame retardant The polyester resin composition of the present invention is characterized by containing (C) a brominated flame retardant in addition to the resin component described above. As a result, it is possible to achieve a strict flame retardant index required for a thin molded article.

  The (C) brominated flame retardant used in the present invention may be any generally known flame retardant. Among them, aromatic compounds are preferable. For example, epoxy oligomer of tetrabromobisphenol A, poly (pentabromobenzyl) Acrylate), polybromophenyl ether, brominated polystyrene, brominated epoxy resin, brominated imide resin, brominated polycarbonate and the like. Among these, from the viewpoint of good thermal stability, an epoxy oligomer of tetrabromobisphenol A, poly (pentabromobenzyl acrylate), and brominated polycarbonate are preferable, and poly (pentabromobenzyl acrylate) is more preferable.

  The polybrominated benzyl (meth) acrylate preferably used in the present invention is obtained by polymerizing a benzyl (meth) acrylate containing bromine alone, copolymerizing two or more kinds, or copolymerizing with another vinyl monomer. The bromine atom is added to the benzene ring, and the number of additions is in the range of 1 to 5, preferably 4 to 5, per benzene ring.

  Examples of the benzyl acrylate containing bromine include pentabromobenzyl acrylate, tetrabromobenzyl acrylate, tribromobenzyl acrylate, pentachlorobenzyl acrylate, tetrachlorobenzyl acrylate, trichlorobenzyl acrylate, and mixtures thereof. Examples of benzyl methacrylate containing bromine include methacrylates corresponding to the above acrylates.

  Vinyl monomers used for copolymerization with benzyl (meth) acrylate containing bromine include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, acrylic esters such as benzyl acrylate, methacrylic acid, methyl Examples thereof include methacrylates such as methacrylate, ethyl methacrylate, butyl methacrylate and benzyl methacrylate, unsaturated carboxylic acids such as styrene, acrylonitrile, fumaric acid and maleic acid or anhydrides thereof, vinyl acetate and vinyl chloride. These are usually used in an equimolar amount or less, preferably 0.5 times or less the molar amount with respect to benzyl (meth) acrylate containing bromine.

  In addition, as the crosslinkable vinyl monomer, xylene diacrylate, xylene dimethacrylate, tetrabromoxylene diacrylate, tetrabromoxylene dimethacrylate, butadiene, isobrene, divinylbenzene, etc. can be used. 0.5 mol or less can be used with respect to benzyl acrylate or benzyl methacrylate containing.

  (C) The compounding quantity of a brominated flame retardant is 3-50 weight part with respect to a total of 100 weight part of (A) aromatic polyester resin and (B) aliphatic polyester copolymer, Preferably it is 6- 30 parts by weight, more preferably 10 to 25 parts by weight. (C) If the amount of the brominated flame retardant is less than 3 parts by weight, the flame retardant effect may be insufficient. If it exceeds 50 parts by weight, the mechanical strength decreases and the thermal stability during melting is reduced. May decrease.

(D) Antimony compound The resin composition of the present invention contains (D) an antimony compound as a flame retardant aid together with the (C) bromine flame retardant.
The antimony compound may be a compound containing antimony, and examples thereof include antimony oxide and antimonate. Examples of the antimony oxide include antimony trioxide (Sb ₂ O ₃ ), antimony tetroxide (Sb ₂ O ₄ ), antimony pentoxide (Sb ₂ O ₅ ) and the like, and examples of the antimonate include sodium antimonate and the like. Can be mentioned. Of these, antimony oxide is preferable, and antimony trioxide (Sb ₂ O ₃ ) is particularly preferable.

The blending amount of the (D) antimony compound in the resin composition is 1 to 30 parts by weight with respect to a total of 100 parts by weight of the (A) aromatic polyester resin and (B) aliphatic polyester copolymer, Preferably it is 2-25 weight part, More preferably, it is 3-20 weight part. (D) If the blending amount of the antimony compound is less than 1 part by weight, a sufficient flame retardant effect may not be obtained. If it exceeds 30 parts by weight, the mechanical strength decreases and the thermal stability at the time of melting. May decrease.
Further, the ratio (weight ratio) [(C) / (D)] of bromine (Br) of the (C) bromine-based flame retardant and (antimony (Sb) of the (D) antimony-based compound is usually 0.00. It is 5 to 4.0, preferably 1.0 to 3.0, particularly 1.4 to 2.2.

(E) Fluorine-containing resin In addition to the components described above, the resin composition of the present invention preferably contains (E) a fluorine-containing resin as an anti-dripping agent. Thereby, there exists a merit that dripping of the resin at the time of combustion can be suppressed.
(E) As the fluorine-containing resin, polyfluoroethylene, particularly polytetrafluoroethylene is preferable, and it has a fibril forming ability, that is, it is easily dispersed in the resin, and the polymers are bonded to each other to form a fibrous material. What shows the tendency to make is preferable. Such polytetrafluoroethylene is classified as type 3 in accordance with ASTM standards. For example, Daikin Chemical Industries' Polyflon FA-500 or F-201L, Asahi Glass Co., Ltd. Fullon CD-123, Mitsui DuPont Fluorochemical It can be obtained as Teflon (registered trademark) 6J.

  The blending amount of the (E) fluorine-containing resin in the resin composition is usually 0 to 10 parts by weight with respect to a total of 100 parts by weight of the (A) aromatic polyester resin and the (B) aliphatic polyester copolymer. However, it is preferably 0.2 to 6 parts by weight, more preferably 0.3 to 4 parts by weight. If the blending amount of the fluororesin exceeds 10 parts by weight, processability such as extrudability and moldability may be impaired.

(F) Reinforcement filler The polyester resin composition of the present invention may contain (F) a reinforcement filler in addition to the above components. As the reinforcing filler, a fibrous reinforcing material is preferable, and the type thereof is not particularly limited. For example, glass fiber, carbon fiber, silica / alumina fiber, zirconia fiber, boron fiber, boron nitride fiber, silicon nitride titanate Examples thereof include inorganic fibers such as potassium fibers and metal fibers, and organic fibers such as aromatic polyamide fibers, aromatic polyester fibers, aramid fibers, fluororesin fibers, and natural fibers. These fibrous reinforcing materials can be used alone or in combination of two or more. Among these, inorganic fibers, particularly glass fibers are preferable.

Although there is no restriction | limiting in particular in the glass fiber used for this invention, For example, glass fibers, such as E glass, C glass, A glass, S glass, and S-2 glass, can be mentioned. Among these, E glass having a low alkali content and good electrical characteristics can be particularly preferably used.
Although there is no restriction | limiting in particular in the average fiber diameter of the fibrous reinforcement used for this invention, 1-100 micrometers, Furthermore, 2-50 micrometers, Especially 3-30 micrometers, Most preferably, 5-20 micrometers is preferable. A fibrous reinforcing material having an average fiber diameter of less than 1 μm is not easy to produce and may increase the cost. Moreover, when the average fiber diameter of a fibrous reinforcement exceeds 100 micrometers, there exists a possibility that the tensile strength of a fibrous reinforcement may fall. Although there is no restriction | limiting in particular in the average fiber length of the fibrous reinforcement used for this invention, 0.1-20 mm, Furthermore, 1-10 mm is preferable. If the average fiber length of the fibrous reinforcing material is less than 0.1 mm, the reinforcing effect by the fibrous reinforcing material may not be sufficiently exhibited. Moreover, when the average fiber length of a fibrous reinforcement exceeds 20 mm, there exists a possibility that melt kneading with resin and shaping | molding of a resin composition may become difficult.

The fibrous reinforcing material used in the present invention, particularly glass fiber, is preferably treated with a surface treatment agent. By treating the surface of the glass fiber with the surface treatment agent, strong adhesion or bonding occurs at the interface between the resin and the glass fiber, stress is transmitted from the resin to the glass fiber, and the reinforcing effect by the glass fiber is exhibited. The surface treatment agent used is not particularly limited, and examples thereof include chlorosilane compounds such as vinyltrichlorosilane and methylvinyldichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, and γ-methacryloxypropyltrimethoxysilane. Such as alkoxysilane compounds such as β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, acrylic compounds, isocyanate compounds, titanate compounds And epoxy compounds.

  The fibrous reinforcing material used in the present invention, particularly glass fiber, is preferably treated with a sizing agent. By treating the glass fiber with the sizing agent, it is possible to improve the handling workability of the glass fiber and prevent the glass fiber from being damaged. There is no restriction | limiting in particular in the sizing agent to be used, For example, resin emulsions, such as a vinyl acetate resin, an ethylene-vinyl acetate copolymer, an acrylic resin, an epoxy resin, a polyurethane resin, a polyester resin, etc. can be mentioned.

  Another filler can be mix | blended with the reinforced polyester resin composition of this invention with the fibrous reinforcement mentioned above. Other fillers include, for example, plate-like inorganic fillers such as glass flakes, mica, metal foil, ceramic beads, asbestos, wollastonite, talc, clay, mica, zeolite, kaolin, potassium titanate, barium sulfate. And particulate inorganic fillers such as titanium oxide, silicon oxide, aluminum oxide, and magnesium hydroxide. Among these, plate-like inorganic fillers, particularly glass flakes, are preferable because they can reduce the anisotropy and warpage of the molded product.

  The content of (F) reinforcing filler is 3 to 150 parts by weight, preferably 5 to 100 parts per 100 parts by weight in total of (A) aromatic polyester resin and (B) aliphatic polyester copolymer. Part by weight, more preferably 10 to 70 parts by weight. If the content of the reinforcing filler is less than 3 parts by weight, the reinforcing effect by the reinforcing filler may not be sufficiently exhibited, and if it exceeds 150 parts by weight, melt kneading and molding of the resin composition are difficult. There is a risk of becoming.

The resin composition of the present invention may contain a flame retardant other than the above-described (C) bromine-based flame retardant, (D) antimony-based compound, and (E) a fluorine-containing resin. Although there is no restriction | limiting in particular in the flame retardant which can be mix | blended, For example, an organic chlorine type compound, a phosphorus compound, another organic type flame retardant, an inorganic type flame retardant etc. can be mentioned. Examples of the phosphorus compound include phosphoric acid ester, polyphosphoric acid, ammonium polyphosphate, and red phosphorus. Examples of other organic flame retardants include nitrogen compounds such as melamine and cyanuric acid. Examples of other inorganic flame retardants include aluminum hydroxide, magnesium hydroxide, silicon compound, and boron compound.

  The flame retardant resin composition of the present invention can be blended with conventional additives as required. For example, heat stabilizers such as hindered phenols, phosphates, phosphites, and thioethers, antioxidants; mold release agents such as paraffin wax, polyethylene wax, stearic acid and esters thereof, and silicone oil; lubricants; Additives such as a catalyst deactivator; a crystal nucleating agent; a crystallization accelerator include (A) an aromatic polyester resin or (B) during or after the polymerization reaction during the production of the aliphatic polyester copolymer. Can be added. In order to further improve the hydrolysis resistance, an epoxy compound, carbodiimide, oxazoline and the like can be added. Furthermore, in order to impart desired performance to polybutylene terephthalate resin, stabilizers such as UV absorbers and weathering stabilizers, coloring agents such as dyes and pigments, antistatic agents, foaming agents, plasticizers, and impact resistance improvements An agent or the like can be blended.

  If necessary, the resin composition of the present invention includes olefin resins such as polyethylene and polypropylene, acrylic resins, polycarbonate resins, polyamide resins, polyphenylene sulfide resins, liquid crystal polyester resins, polyacetal resins, polyphenylene oxide resins, and the like. Thermosetting resins such as epoxy resins, epoxy resins, phenol resins, melamine resins, and silicone resins can be blended. These resins can be used alone or in combination of two or more.

  The polyester resin composition of the present invention is the above-mentioned (A) aromatic polyester resin, (B) aliphatic polyester copolymer, (C) brominated flame retardant, (D) antimony compound, and used as necessary. It is produced by a method of blending various additives and the like, dry blending or melt kneading. Dry blending is performed using, for example, a ribbon blender, a Henschel mixer, a drum blender, or the like. Melt kneading is performed using various extruders, Brabender plastographs, lab blast mills, kneaders, Banbury mixers, and the like. The heating temperature at the time of melt kneading is usually 230 to 290 ° C. In order to suppress decomposition during kneading, it is preferable to use the above heat stabilizer. Each component including an additional component can be supplied to the kneader in a lump or sequentially. Furthermore, two or more kinds of components selected from each component including additional components can be mixed in advance. By adding a reinforcing filler such as glass fiber after the resin is melted from the middle of the extruder, it can avoid crushing and exhibit high characteristics.

  The flame-retardant polyester resin composition of the present invention can be produced by various molding methods known as thermoplastic resin molding methods such as injection molding, hollow molding, extrusion molding, compression molding, calendar molding, and rotational molding. It can be applied to be molded into various products used in electrical / electronic equipment field, automobile field, machine field, medical field, packaging field, textile field and the like. Since the resin composition of the present invention has good fluidity, the injection molding method is particularly preferable. In particular, it is suitable for injection molding thin molded products such as relay cases and large molded products such as automobile outer plates. During injection molding, it is preferable to control the resin temperature to 240 to 280 ° C.

The flame-retardant polyester resin composition of the present invention is excellent in biodegradability and impact resistance, and is expected to be used as various structural materials particularly requiring impact resistance. Specifically, for example, aircraft, rockets, artificial satellites and other aircraft / spacecraft, railways, boats, automobiles, motorcycles, bicycles and other transportation equipment structural materials, outer panels, pressure members; electrical and electronic equipment Cases and internal precision parts; various office supplies such as writing utensils, desks and chairs, and daily necessities including various resin structures can be suitably used. Since it is particularly excellent in impact strength, it can be suitably used as an insert molded product that requires stability against heat shock.

  In addition, the flame-retardant polyester resin composition of the present invention is excellent in molding processability (fluidity) and has high productivity. Therefore, among the applications described above, particularly, structural materials for motorcycles and automobiles with high production volume, In addition to an outer plate, a pressure member, etc., it is preferably used as a resin structure typified by minute precision parts such as a housing in an electric / electronic device and a gear inside a machine. Specifically, basic frame materials such as motorcycle main frames and automobile platforms; front panels, hoods, roofs, hard top roofs, pillars, trunk lids, doors, fenders, side mirror covers, etc .; Aerodynamic members such as air dams, rear spoilers, side air dams, and engine undercovers; automotive interior materials such as instrument panels; housings for electrical and electronic equipment such as flexible disks and hard disks; minute precision such as gears, wiring connectors, and various switches Examples include resin structures such as parts.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not restrict | limited to the following examples, unless the summary is exceeded. The raw materials and physical property measurement methods used in the following examples are as follows.

[raw materials]
(A) Aromatic polyester resin (A-1) PBT1
Both raw materials were supplied to a slurry preparation tank at a ratio of 1.8 mol of 1,4-butanediol to 1.0 mol of terephthalic acid, and 1,000 parts by weight of the slurry prepared by mixing with a stirrer was continuously added. And transferred to a first esterification reaction vessel adjusted to a temperature of 230 ° C. and a pressure of 101 kPa by a gear pump, and 0.158 parts by weight of tetrabutyl titanate (30 ppm as Ti amount relative to the theoretical polymer) is supplied, The oligomer was obtained by esterification with stirring.

The oligomer obtained in the first esterification reaction tank was transferred to a second esterification reaction tank adjusted to a temperature of 240 ° C. and a pressure of 101 kPa, and the esterification reaction was further advanced with stirring for 1 hour.
Next, the oligomer obtained in the second esterification reaction tank was heated at a temperature of 250 ° C. and a pressure of 6.67.
It was transferred to a first polycondensation reaction tank adjusted to kPa, and a polycondensation reaction was carried out with stirring for 2 hours to obtain a prepolymer.

Furthermore, the prepolymer obtained in the first polycondensation reaction tank was transferred to a second double condensation reaction tank adjusted to a temperature of 250 ° C. and a pressure of 133 Pa, and the polycondensation reaction was further advanced with stirring for 3 hours. To obtain a polymer. The polymer was extracted from the second double condensation tank, transferred to a die, drawn into a strand, and cut with a pelletizer to obtain a beret-like polybutylene terephthalate resin (PBT1).
The resulting polybutylene terephthalate resin (PBT1) had a terminal carboxyl group concentration of 20 eq / ton, an intrinsic viscosity of 0.85 dl / g, and a residual tetrahydrofuran amount of 18
It was 0 ppm (weight ratio).

(A-2) PBT2
A total of 1,000 parts by weight of both raw materials was supplied to the transesterification reaction tank so that the ratio of 1.8 mol of 1,4-butanediol to 1.0 mol of dimethyl terephthalate was 0.53 tetrabutyl titanate. Part by weight (100 ppm as the amount of Ti with respect to the theoretical polymer) was added and subjected to a transesterification reaction at a temperature of 210 ° C. and a pressure of 101 kPa for 3 hours to obtain an oligomer.

Subsequently, the obtained oligomer was transferred to a polycondensation reaction tank, and under agitation, a polycondensation reaction was carried out at a temperature of 250 ° C. and a pressure of 133 Pa for 3 hours to obtain a polymer. Next, nitrogen pressure was applied to extract the strand, and the pellet was cut with a pelletizer to obtain a pellet-like polybutylene terephthalate resin (PBT2).
The resulting polybutylene terephthalate resin (PBT2) had a terminal carboxyl group concentration of 41 eq / ton, an intrinsic viscosity of 0.85 dl / g, and a residual tetrahydrofuran amount of 68.
It was 0 ppm.

(A-3) PBT3
In the production method of PBT2, pellets were similarly used except that the amount of tetrabutyl titanate used was 1.00 parts by weight, the polymerization temperature of the polycondensation reaction was 260 ° C., the polymerization pressure was 333 Pa, and the polymerization time was 4 hours. -Shaped polybutylene terephthalate resin (PBT3) was obtained.
The resulting polybutylene terephthalate resin (PBT3) has a terminal carboxyl group concentration of 55 eq / ton, an intrinsic viscosity of 0.85 dl / g, and a residual tetrahydrofuran amount of 70.
It was 0 ppm (weight ratio).

(B) Aliphatic polyester copolymer (B-1) Aliphatic polyester copolymer 1 (PBSL)
In a reaction vessel equipped with a stirrer, a nitrogen inlet, a heating device, and a decompression device, 118.1 parts by weight of succinic acid, 104.5 parts by weight of 1,4-butanediol, and 1% by weight of germanium oxide were dissolved in advance 90 6.40 parts by weight of a weight% lactic acid aqueous solution and 0.2 parts by weight of super talc as a crystal nucleating agent were charged, and the system was placed in a nitrogen atmosphere by nitrogen replacement. Next, the temperature was raised to 220 ° C. while stirring the system, and the reaction was carried out at this temperature for 1 hour. Thereafter, the temperature was raised to 230 ° C. over 30 minutes, and at the same time, the pressure was reduced to 0.07 × 10 ³ Pa over 1 hour and 30 minutes, and the reaction was performed under this pressure for 4 hours to obtain white polyester. The intrinsic viscosity of the obtained polyester was 1.82 dl / g. The mol% of each component was 48.8 mol% succinic acid units, 48.8 mol% 1,4-butanediol units, and 2.4 mol% lactic acid units. Let the obtained aliphatic polyester be PBSL (polybutylene succinate lactate).

(B-2) Aliphatic polyester copolymer 2 (PBSLA)
(B-1) In the manufacturing method of aliphatic polyester copolymer-1, except that 118.1 parts by weight of succinic acid was used, 94.48 parts by weight of succinic acid and 29.23 parts by weight of adipic acid were used. Similarly, a polymerization reaction was performed. The intrinsic viscosity of the obtained polyester polymer was 1.82 dl / g. The mol% of each component was 38.7 mol% succinic acid unit, 48.8 mol% 1,4-butanediol unit, 2.8 mol% lactic acid unit, and 9.7 mol% adipic acid unit. The obtained aliphatic polyester is designated as PBSLA (polybutylene succinate lactate adipate).

(C) Brominated flame retardant Poly (pentabromobenzyl acrylate): Bromochem Far East, trade name PBBPA
(D) Antimony compound Antimony trioxide: manufactured by Morirokusha, trade name MIC-3

(E) Fluorine-containing resin Polytetrafluoroethylene (PTFE): Daikin Industries, Ltd., trade name Polyflon FA-500
(F) Reinforcing filler Glass fiber: manufactured by Nippon Electric Glass Co., Ltd., trade name T-187, average fiber diameter 13 μm, average fiber length 3 mm

[Physical property measurement method]
(1) Intrinsic viscosity About PBT resin, it calculated | required from the solution viscosity measured at 30 degreeC in the mixed solvent of 1,1,2,2-tetrachloroethane / phenol = 1: 1 (weight ratio) using the Ubbelohde viscometer. . The Haggins constant was 0.33.
(2) Terminal carboxyl group concentration 0.1 g of resin was dissolved in 3 ml of benzyl alcohol, and a titration method was performed using a sodium hydroxide 0.1 mol / 1 liter benzyl alcohol solution.

(3) Ti atom content The titanium metal concentration (weight ratio) in the PBT resin was quantified by Induced Coupled Plasma (ICP).
(4) Residual tetrahydrofuran amount (THF amount)
5 g of PBT resin pellets were immersed in 10 g of water, treated under pressure at 120 ° C. for 6 hours, and tetrahydrofuran eluted in water was quantified by gas chromatography.
(5) Polymer composition
The composition (mol%) of each component was calculated from the area ratio of the spectrum measured by ¹ H-NMR method.

(6) Mechanical properties Charpy impact test: Measured according to ISO 179-2.
(7) Melt viscosity Melt viscosity was measured using a Capillograph 1C manufactured by Toyo Seiki under conditions of 270 ° C and a shear rate of 6080 sec- ¹ . It shows that it is excellent in fluidity | liquidity, so that the value of melt viscosity is low.

(8) Flame retardancy From the resin compositions obtained in Examples and Comparative Examples, a test piece having a thickness of 1/32 inch was molded, and UL-94 “under the classification of materials by Underwriters Laboratories Corporation”. The test was conducted according to the method shown in “Burn test” (hereinafter referred to as UL-94), and the grade was evaluated to any of the following UL-94 standards based on the results of five test pieces.

V-0: The average flame holding time after removing the ignition flame is 5 seconds or less, and all the test pieces do not drop a fine flame that ignites absorbent cotton.
V-1: The average flame holding time after removing the ignition flame is 25 seconds or less, and all the test pieces do not drop a fine flame that ignites absorbent cotton.
V-2: The average flame holding time after removing the ignition flame is 25 seconds or less, and the absorbent cotton is ignited from the particulate flame dropped from these test pieces.
Fail: Burns above the determination criteria of V-0, V-1, and V-2.

(9) Hydrolysis resistance The ISO test piece was wet-heat treated for 75 hours under the conditions of a temperature of 80 ° C and a humidity of 95%. The tensile strength before and after the wet heat treatment was measured according to ISO 527, and the tensile strength retention was determined according to the following formula. The higher the retention value, the higher the hydrolysis resistance.
Tensile strength retention (%) = (Tensile strength after treatment / Tensile strength before treatment) × 100

[Examples 1 to 5 and Comparative Examples 1 to 4]
A mixture obtained by dry blending components other than glass fibers so as to have a blending ratio shown in Table 1 was charged from a main feeder of a twin screw extruder (manufactured by Nippon Steel Works, TEX30HSST L / D = 42), Glass fiber was introduced from a side feeder, extruded under the conditions of a discharge rate of 20 kg / h, a screw rotation speed of 150 rpm, and a barrel temperature of 260 ° C., and pelletized to obtain pellets of a resin composition. From the obtained pellets, an ISO test piece was molded under the conditions of a cylinder temperature of 250 ° C. and a mold temperature of 80 ° C. by an injection molding machine (manufactured by Sumitomo Heavy Industries, model SH-100). Characteristics and hydrolysis resistance were measured. In addition, flame retardancy was evaluated from the obtained pellets according to the method described above. The results are shown in Table 1.

表１の結果から以下のことが判明する。
（１）（Ａ）ＰＢＴ樹脂に（Ｂ）脂肪族ポリエステル共重合体と（Ｃ）臭素化芳香族化合物、及び（Ｄ）アンチモン系化合物を配合した実施例１〜５の樹脂組成物は、該（Ｂ）共
重合体を配合しない比較例１及び２と比較すると、衝撃強度及び成形加工性（流動性）が向上している。

From the results in Table 1, the following is found.
(1) The resin compositions of Examples 1 to 5 in which (B) an aliphatic polyester copolymer, (C) a brominated aromatic compound, and (D) an antimony compound are blended with (A) PBT resin, (B) Impact strength and moldability (fluidity) are improved as compared with Comparative Examples 1 and 2 in which no copolymer is blended.

(2) Example 4 in which the terminal carboxyl group concentration of (A) PBT resin is 41 eq / ton is superior in impact strength and hydrolysis resistance compared to Comparative Example 3 in which the concentration is 55 eq / ton.
(3) The resin composition of Example 2 using the PBT resin 1 having a terminal carboxyl group concentration of 20 eq / ton was more resistant to water than Example 4 using the PBT resin 2 having a terminal carboxyl group concentration of 41 eq / ton. Degradability is better.

Claims (6)

(A) 1 to 99 parts by weight of the aromatic polyester resin and (B) 1 to 99 parts by weight of the aliphatic polyester copolymer, and 100 parts by weight of (C) 3 to 50 parts by weight of the brominated flame retardant And (D) a flame retardant polyester resin composition containing 1 to 30 parts by weight of an antimony compound, wherein the terminal carboxyl group concentration of the (A) aromatic polyester resin is 50 eq / ton or less, B) Aliphatic polyester copolymer is 0-30 mol% of aliphatic oxycarboxylic acid units represented by the following formula (I), aliphatic and / or alicyclic diols represented by the following formula (II) A flame retardant polyester resin composition comprising 35 to 50 mol% of a unit and 35 to 50 mol% of an aliphatic dicarboxylic acid unit represented by the following formula (III).

  The flame-retardant polyester resin composition according to claim 1, wherein the (A) aromatic polyester resin is a polybutylene terephthalate resin.   The flame-retardant polyester resin composition according to claim 1 or 2, wherein the content of the titanium compound in the (A) aromatic polyester resin is 70 ppm (weight ratio) or less in terms of titanium atoms.   The flame-retardant polyester according to any one of claims 1 to 3, wherein the (B) aliphatic polyester copolymer contains 0.5 to 20 mol% of an aliphatic oxycarboxylic acid unit represented by the formula (I). Resin composition.   The amount of (F) fluorine-containing resin is 0.2 to 6 parts by weight with respect to a total of 100 parts by weight of the (A) aromatic polyester resin and the (B) aliphatic polyester copolymer. The flame-retardant polyester resin composition according to any one of the above.   A polyester resin structure formed by molding the resin composition according to claim 1.