JP2011231178A - Polyester elastomer resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester elastomer resin composition which has excellent crystallinity in spite of a low melting point and excellent flexibility, flame retardancy, and thermal stability, is easily fabricated into a molded article, such as various parts, films, and fibers, and can be suitably used in various adhesive applications.SOLUTION: The polyester elastomer resin composition includes a polyester which comprises a dicarboxylic acid component mainly composed of terephthalic acid and a diol component mainly composed of 1,6-hexanediol and with which an organophosphorus compound is copolymerized, as a hard segment and polyalkylene glycol having an average molecular weight of 500-5,000, as a soft segment. The polyester elastomer resin composition has the ratio of the soft segment of 5-50 mass%, a melting point of 100-150°C, and the content of a phosphorus atom of 2,000-15,000 ppm, contains 0.01-3.0 mass% of a crystal nucleating agent, and has Shore hardness of 20-60.

Description

  The present invention relates to a polyester elastomer resin composition which has high crystallinity despite its low melting point, has flexibility, has flame retardancy, and is excellent in operability and productivity.

  Polyester elastomer has thermoplastic properties in addition to excellent mechanical properties such as flexibility, elastic recovery, strength, impact resistance, etc., and can be easily molded. Widely used in automotive parts, electrical parts, molded products, films and fibers.

  However, polybutylene terephthalate is used for the hard segment, which is generally used as a polyester elastomer, and an aliphatic polyether unit such as poly (alkylene oxide) glycol and / or an aliphatic polyester unit such as polylactone is used for the soft segment. Since the polyester elastomer (Patent Document 1) using the material has a low melting point of 160 ° C., which is higher than the melting point of polyethylene, which is the most common as a molding material, is 130 ° C., an excessive energy cost is required for molding. Become.

  In addition, polyester elastomers that use aliphatic polyether units such as poly (alkylene oxide) glycol and / or aliphatic polyester units such as polylactone in the soft segment are poor in flame retardancy and have reduced viscosity due to thermal decomposition. It is also common that the temperature is severe, and imparting flame retardancy and thermal stability is one of the problems.

  In addition, polyester resins have a high demand for those having a low melting point, and are used for binder fibers, adhesives, and the like. For such applications, a copolyester is generally used. For example, Patent Document 2 shows a binder polymer having a low melting point near 130 ° C. and excellent dimensional stability as a suitable polymer. Copolyesters that enable this have been proposed.

  However, since these polymers lack flexibility, when used as binder fibers or adhesives, the strength at the bonding point is low, and the adhesive strength may be inferior.

Japanese Patent Laid-Open No. 06-329888 JP 2008-248218 A

  The present invention solves the above-mentioned problems and has excellent crystallinity despite its low melting point, and excellent flexibility, flame retardancy, thermal stability, various parts, films, fibers, etc. It is an object of the present invention to provide a polyester elastomer resin composition that can be easily processed into a molded article and can be suitably used for various adhesive applications.

The present inventor has reached the present invention as a result of studies to solve the above-mentioned problems.
That is, the present invention comprises a polyester comprising a dicarboxylic acid component containing terephthalic acid as a main component and a diol component containing 1,6-hexanediol as a main component, and an organic phosphorus compound copolymerized, as a hard segment, and having an average molecular weight of 500. A polyester elastomer resin composition having a soft segment of ˜5000 polyalkylene glycol, the proportion of the soft segment is 5 to 50 mass%, the melting point is 100 to 150 ° C., and the phosphorus atom content is 2000 to 15000 ppm. And a polyester elastomer resin composition characterized by containing 0.01 to 3.0% by mass of a crystal nucleating agent and having a Shore hardness of 20 to 60.

  The polyester elastomer resin composition of the present invention is excellent in crystallinity in spite of a low melting point, has little occurrence of blocking when being formed into chips or after being formed into chips, and is excellent in operability. Furthermore, the polyester elastomer resin composition of the present invention is excellent in flexibility and flame retardancy, and can be easily processed into sheets, films, various parts and fibers, and various molded products can be obtained. It is. Moreover, since the polyester elastomer resin composition of the present invention has flexibility, when used as a binder fiber or an adhesive, the strength at the adhesion point is increased, and it can be suitably used for various adhesive applications. it can.

It is an example of the DSC curve which shows the temperature-fall crystallization calculated | required from DSC of the polyester elastomer resin composition in this invention.

Hereinafter, the present invention will be described in detail.
The polyester elastomer resin composition of the present invention comprises a polyester hard segment and a polyalkylene glycol soft segment.

  First, the hard segment will be described. In the hard segment polyester, the dicarboxylic acid component has terephthalic acid as the main component, and the diol component has 1,6-hexanediol as the main component.

  As the dicarboxylic acid component, terephthalic acid (TPA) is preferably 60 mol% or more, and more preferably 80 mol% or more. If the TPA is less than 60 mol%, the melting point of the polymer falls outside the range of the present invention, and the crystallinity tends to decrease, which is not preferable.

  In addition, as a copolymerization component other than TPA, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, dodecanedicarboxylic acid, 1,3-cyclobutanedicarboxylic acid are within the range that does not impair the effect. Acid, saturated aliphatic dicarboxylic acid exemplified by 1,4-cyclohexanedicarboxylic acid, dimer acid and the like, or ester-forming derivatives thereof, unsaturated aliphatic dicarboxylic acid exemplified by fumaric acid, maleic acid, itaconic acid and the like Aromatic dicarboxylic acids exemplified by these ester-forming derivatives, phthalic acid, isophthalic acid, 5- (alkali metal) sulfoisophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, and the like These ester-forming derivatives are mentioned. Examples of polyvalent carboxylic acids other than dicarboxylic acids include butanetetracarboxylic acid, pyromellitic acid, trimellitic acid, trimesic acid, 3,4,3 ′, 4′-biphenyltetracarboxylic acid, and ester-forming derivatives thereof. Can be mentioned.

Examples of the hydroxycarboxylic acid include lactic acid, citric acid, malic acid, hydroxyacetic acid, 3-hydroxybutyric acid, p-hydroxybenzoic acid, and ester-forming derivatives thereof.
Examples of ester-forming derivatives of polyvalent carboxylic acids or hydroxycarboxylic acids include these alkyl esters, acid chlorides, acid anhydrides, and the like.

  As the diol component, 1,6-hexanediol (hereinafter referred to as HD) is preferably 60 mol% or more, and more preferably 80 mol% or more. When the HD is less than 60 mol%, the melting point of the polymer is outside the range of the present invention, and the crystallinity tends to be lowered, which is not preferable.

  In addition, as a copolymer component other than HD, the diol component includes ethylene glycol (hereinafter referred to as EG), 1,4-butanediol (hereinafter referred to as BD), and 1 as long as the characteristics are not impaired. , 2-propylene glycol, 1,3-propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,4-cyclohexanediol, 1, Aliphatic glycols exemplified by 4-cyclohexanedimethanol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol and the like, hydroquinone, 4,4′-dihydroxybisphenol, 1,4-bis (β-hydroxyethoxy) benzene, Bisphenol A 2,5-naphthalene diol, an aromatic glycol exemplified such as glycol ethylene oxide is added to these glycols.

Examples of the polyhydric alcohol other than glycol include trimethylolmethane, trimethylolethane, trimethylolpropane, pentaerythritol, glycerol, hexanetriol and the like.
Examples of the cyclic ester include ε-caprolactone, β-propiolactone, β-methyl-β-propiolactone, δ-valerolactone, glycolide, and lactide.

  An organic phosphorus compound is copolymerized with the hard segment polyester. The amount of copolymerization of the organic phosphorus compound must be such that the phosphorus atom content is 2000-15000 ppm in the polyester elastomer resin composition, and the phosphorus atom content is 4000-10000 ppm. Is preferred.

  When the copolymerization amount of the organic phosphorus compound is less than 2000 ppm as the phosphorus atom content, sufficient flame retardancy is not obtained. On the other hand, if it exceeds 15000 ppm, the crystallinity is lowered and the polymerizability of the polyester is deteriorated, so that it is difficult to sufficiently increase the degree of polymerization. As a result, the strength and the like of the molded product obtained from the polyester elastomer resin composition are not preferable.

  As the organic phosphorus compound used in the present invention, an organic phosphorus compound represented by the following general formula [1] is preferable, and more specifically, an organic phosphorus compound represented by the following formulas (a) to (c) is preferable.

  Among these, when comprehensively judging the stability of the organophosphorus compound, the high phosphorus atom content, the volatility of the organophosphorus compound in the manufacturing process, the low scattering, etc., the above formula (a) is obtained. The compound, itaconic acid adduct of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (hereinafter abbreviated as HCA-IA), is preferred. In addition, phosphorane, dimethyl phenylphosphonate, diphenyl phenylphosphonate, (2-carboxylethyl) methylphosphinic acid, (2-carboxylethyl) phenylphosphinic acid, methyl (2-methoxycarboxylethyl) phenylphosphinate, (4 -Methoxycarbonylphenyl) phenylphosphinic acid methyl, [2- (β-hydroxyethoxycarbonyl) ethyl] methylphosphinic acid ethylene glycol ester and the like.

  As a method of copolymerizing the above organic phosphorus compound with polyester, a method in which the organic phosphorus compound is added to the reaction system as it is when the polyester is produced and reacted is industrially preferable. Alternatively, it may be added to the reaction system after reacting with methanol or the like to form an ester.

  Next, the soft segment will be described. As the polyalkylene glycol of the soft segment, a polyalkylene glycol having a molecular weight of 500 to 5000, preferably 1000 to 3000 is used, and among them, polytetramethylene glycol (PTMG) and polyethylene glycol (PEG) are preferably used.

  When the average molecular weight of the polyalkylene glycol is less than 500, sufficient elastic properties cannot be obtained, and the resulting polyester elastomer resin composition has high Shore hardness and poor flexibility. On the other hand, if it exceeds 5000, the compatibility with the polyester forming the hard segment will be poor, a uniform polymer will not be obtained, and the elastic properties will also deteriorate.

  In the polyester elastomer resin composition of the present invention, the proportion of the soft segment is 5 to 50% by mass, preferably 10 to 40% by mass, and more preferably 15 to 35% by mass. When the proportion of the soft segment is less than 5% by mass, sufficient adhesion and elastic properties cannot be obtained, and the Shore hardness is high. On the other hand, if it exceeds 50% by mass, some of the soft segments cannot be completely copolymerized with the hard segments, or the melt viscosity of the polymer becomes low, and the workability of the polymer dispensing process and the subsequent processing process is inferior. Become.

  The polyester elastomer resin composition of the present invention is a hindered phenolic antioxidant or phosphorus antioxidant in order to improve thermal stability over time, which is a problem when polyalkylene glycol is used as a soft segment. In particular, it is preferable to contain a hindered phenol antioxidant. The content of the polyester elastomer resin composition of these antioxidants is preferably 0.05 to 1.0% by mass, and more preferably 0.07 to 0.7% by mass. When the content of these antioxidants is less than 0.05% by mass, the thermal stability of the polyester elastomer resin composition is not improved, and after a long period of time, the intrinsic viscosity is lowered and the color tone is likely to deteriorate after molding. On the other hand, when the content exceeds 1.0% by mass, the polycondensation reaction rate is lowered and the color tone and transparency of the polyester elastomer resin composition are liable to deteriorate.

  As the hindered phenol antioxidant, 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) Propionate, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 4, 4′-butylidenebis- (3-methyl-6-tert-butylphenol), triethylene glycol-bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], 3,9-bis { 2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1′-dimethylethyl} -2,4,8,1 -Tetraoxaspiro [5,5] undecane and the like are used, but tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane is preferable in terms of effect and cost. .

  Examples of phosphorus antioxidants include triphenyl phosphite, trioctadecyl phosphite, trisnonylphenyl phosphite, trilauryl trithiophosphite, bis (2,4-di-t-butylphenyl) pentaerythritol- Diphosphite, bis (3-methyl-1,5-di-t-butylphenyl) pentaerythritol-diphosphite, tris (2,4-di-t-butylphenyl) phosphite, bis (2,4-di-t- Phosphite antioxidants such as butylphenyl) pentaerythritol-diphenylphosphite and diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, bis (3,5- And phosphonic acid ester-based antioxidants such as di-t-butyl-4-hydroxybenzylphosphonic acid ethyl) calcium.

  The melting point of the polyester elastomer resin composition of the present invention is 100 to 150 ° C, preferably 110 to 140 ° C, more preferably 115 to 135 ° C. When the melting point of the polyester elastomer resin composition is less than 100 ° C., the thermal stability is deteriorated, so that the operability and productivity are also lowered. On the other hand, if the melting point exceeds 150 ° C., heat treatment at a high temperature is required at the time of molding or bonding, which is disadvantageous in cost.

The polyester elastomer resin composition of the present invention has a Shore hardness of 20 to 60, and preferably 30 to 55. If the Shore hardness is less than 20, the resulting molded article or fiber has low mechanical strength, whereas if it exceeds 60, the flexibility is inferior.
The Shore hardness in the present invention is measured using a type D durometer according to ASTM D-2240.

  The polyester elastomer resin composition of the present invention has crystallinity due to the composition as described above, but improves the crystallization rate during cooling by containing a crystal nucleating agent. It is preferable to satisfy the following formula (1).

  The polyester elastomer resin composition of the present invention contains 0.01 to 3.0% by mass of a crystal nucleating agent, preferably 0.1 to 1.0% by mass. When the content of the crystal nucleating agent in the polyester elastomer resin composition is less than 0.01% by mass, the crystallization rate at the time of cooling cannot be improved, and the polyester elastomer resin composition is described later in formula (1). It becomes difficult to satisfy. On the other hand, if it exceeds 3.0% by mass, the content of the crystal nucleating agent is excessively increased, the polymerizability and workability are deteriorated, and the operability in producing the resin and forming the molded product is deteriorated.

As the crystal nucleating agent, organic fine particles, organic compounds composed of polyolefin, sulfates, and the like can be used. Of these, organic compounds composed of polyolefin are preferred. As the inorganic fine particles, those mainly composed of silicon oxide such as talc are preferable, and inorganic fine particles having an average particle diameter of 3.0 μm or less or a specific surface area of 15 m ² / g or more are preferably used.

  In addition, the organic compound comprising polyolefin is not particularly limited in shape because it melts in the reaction system. For example, a chip-like one having a particle size of about 2 mm or a wax-like one having a particle size of several μm is used. Can be mentioned. Of these, wax-like ones are preferred.

  Examples of polyolefins include olefin homopolymers such as polyethylene, polypropylene, poly-1-butene, polymethylpentene, and polymethylbutene, and propylene / ethylene random copolymers. Polyethylene, polypropylene, poly-1- Butene and propylene / ethylene random copolymers are particularly preferred. When the polyolefin is a polyolefin obtained from an olefin having 3 or more carbon atoms, it may be an isotactic polymer or a syndiotactic polymer. The polyolefin may be obtained by any production method and catalyst. For example, not only polyolefin obtained by a conventional Ziegler-Natta type catalyst but also polyolefin obtained by a metallocene catalyst is suitable. Can be used for Such polyolefin may be used independently and may be used in combination of 2 or more type.

  Examples of the sulfate contained as a crystal nucleating agent include lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate, barium sulfate, calcium sulfate, and aluminum sulfate. Sodium and magnesium sulfate are preferred.

In the polyester elastomer resin composition of the present invention, the DSC curve indicating the temperature-falling crystallization obtained from DSC preferably satisfies the following formula (1), and it is particularly preferable that b / a ≧ 0.04. On the other hand, the larger b / a, the better the crystallinity when the temperature is lowered. However, in order to achieve the intended effect of the present invention, b / a is preferably 0.5 or less.
b / a ≧ 0.03 (mW / mg · ° C.) (1)

  The DSC curve showing the temperature drop crystallization determined from the melting point of the polyester elastomer resin composition and DSC in the present invention is a temperature range of −20 ° C. in a nitrogen stream using a Perkin Elmer differential scanning calorimeter (Diamond DSC). It is measured at ˜250 ° C., temperature rising (falling temperature) rate of 20 ° C./min, sample amount of 2 mg.

  Said b / a is calculated | required from the DSC curve which shows the temperature-fall crystallization calculated | required from DSC. As shown in FIG. 1, a is the temperature A1 (° C.) of the intersection of the tangent line and the base line with the maximum inclination in the DSC curve indicating the temperature-falling crystallization, the tangent line and the base line with the minimum inclination. Is the difference (A1−A2) from the temperature A2 (° C.) at the intersection of the two, and b is the difference (B1−B2) between the baseline heat amount B1 (mW) and the peak top heat amount B2 (mW) at the peak top temperature. ) Divided by the sample amount (mg).

  b / a is an index representing the crystallinity when the temperature is lowered, and the higher the b / a value, the faster the crystallization rate, and vice versa, the closer to 0, the slower the crystallization rate. When the value of b / a is 0.03 or more, the crystallization speed of the resin composition increases, so that blocking occurs during storage, transportation, drying, etc. when the resin composition is chipped or after chipping. It will be difficult. On the other hand, when b / a is less than 0.03 (mW / mg · ° C.), the crystallization rate is slow. Therefore, when chipping the resin composition, after chipping, in storage, transportation, drying processes, etc. Blocking tends to occur.

  Said b / a can be set to the range prescribed | regulated by this invention by adjusting the copolymerization composition of a polyester elastomer resin composition, and content of a crystal nucleating agent.

  The polyester elastomer resin composition of the present invention preferably has an intrinsic viscosity of 0.5 or more. A material having an intrinsic viscosity of less than 0.5 is not preferable because various physical, mechanical and chemical properties are inferior. On the other hand, even if the intrinsic viscosity is too high, the melt viscosity becomes high, so that extrusion is likely to be difficult, and it is preferably 1.5 or less for practical use.

  In the polyester elastomer resin composition of the present invention, a color tone improver such as a cobalt compound, a fluorescent whitening agent, a dye, a matting agent such as titanium dioxide, a plasticizer, a pigment, One type or two or more types of various additives such as antistatic agents and dyeing agents may be added.

  Next, the manufacturing method of the polyester elastomer resin composition of this invention is demonstrated using an example. The polyester elastomer resin composition of the present invention is produced by subjecting a dicarboxylic acid component, a diol component, and a polyalkylene glycol to an esterification reaction or a transesterification reaction, and performing a polycondensation reaction to produce the polyester elastomer resin composition of the present invention. Can do.

  Specifically, the polycondensation reaction is usually performed under a reduced pressure of about 0.01 to 10 hPa at a temperature of 220 to 280 ° C. until a product having a predetermined intrinsic viscosity is obtained. The polycondensation reaction is carried out in the presence of a catalyst. As a catalyst, conventionally used metals such as antimony, germanium, tin, titanium, zinc, aluminum, magnesium, potassium, calcium, sodium, manganese and cobalt are commonly used. In addition to the compounds, organic sulfonic acid compounds such as sulfosalicylic acid and o-sulfobenzoic anhydride can be used.

  Organophosphorus compound, crystal nucleating agent and various additives (can be used as long as the effects of the present invention are not impaired) are added at any stage when producing polyester in the form of powder or diol slurry. do it. For example, it may be added at the time of esterification or transesterification, or may be added at the stage of polycondensation reaction.

  When the polyester reaches a predetermined intrinsic viscosity in the polycondensation reaction, it is discharged into a strand shape, cooled, and cut into chips.

  The polyester elastomer resin composition of the present invention can be easily processed into a sheet, film, various parts, etc. by injection molding, blow molding, extrusion molding, etc., and is fiberized by melt spinning to form a binder fiber. It is also possible. Furthermore, it can be suitably used for various adhesive applications as an adhesive.

Next, the present invention will be specifically described using examples.
The measurement and evaluation methods for various characteristic values in the examples are as follows.
(A) Intrinsic viscosity [η]
Measurement was carried out based on a conventional method under the conditions of a sample concentration of 0.5% by mass and a temperature of 20 ° C. using an equal mass mixture of phenol and ethane tetrachloride as a solvent.
(B) Melting point, DSC curve showing cooling crystallization determined from DSC Measured by the method described above.
(C) Polymer composition The obtained polyester elastomer resin composition was dissolved in a mixed solvent having a volume ratio of 1/20 of deuterated hexafluoroisopropanol and deuterated chloroform, and the mixture was applied to an LA-400 type NMR apparatus manufactured by JEOL Ltd. 1H-NMR was measured and obtained from the integral intensity of the proton peak of each copolymer component in the obtained chart.
(D) Shore hardness It measured by the said method.
(E) Flame retardancy The flame retardancy of the obtained polyester elastomer resin composition is measured according to JIS K 7201 by measuring LOI value (limit oxygen index). Things were rejected (x).
(F) Thermal stability The obtained polyester elastomer resin composition was treated at 250 ° C. for 1 hour under nitrogen, and the difference in intrinsic viscosity before and after the treatment was within 0.05. Those exceeding were considered as rejected (x).
(G) Operability (chip)
When a polyester elastomer resin composition is made into chips with an AUTOMATIK USG-600 type cutter, due to the occurrence of a fusion of two or more chips due to winding of polyester around a feed roller or cutter blade or fusion between strands, etc. If the operation of the cutter is interrupted x, problems such as fusing will occur, and if it is interrupted from time to time, it will be △, if there is a problem such as fusing, insert without interrupting the operation of the cutter The case where it was able to be made into a chip without causing a problem due to fusion was marked as ◎. ○ and ◎ were accepted.
[Chip blocking]
When the chip storage / transport and drying process produces a block-like lump that does not collapse or a fused product on the wall surface, there is a block-like lump or deposit on the wall surface, and direct impact is applied with a hammer, etc. △ When it is resolved by a certain amount of force, there is a block-like lump or deposit on the wall, but it can be resolved by touching with a hand or applying an impact to the wall with a hammer etc. ○, when no block lump or fusion to the wall surface occurred at all. ○ and ◎ were accepted.

Example 1
Esterification reactor, 22 kg of TPA, 22 kg of HD, 15 kg of PTMG with an average molecular weight of 1000, 6 kg of HD solution containing 63% by mass of HCA-IA as an organophosphorus compound, 50 g of polyethylene wax as crystal nucleating agent, catalyst As a result, 10 g of monobutyltin hydroxyoxide was supplied and reacted under the conditions of a temperature of 250 ° C. and a normal pressure to obtain a transparent esterification reaction product. This reaction product was transferred to a polycondensation reaction vessel, and 1.1 kg of EG solution containing 4% by mass of tetrabutyl titanate as a polycondensation catalyst was charged into the polycondensation reaction vessel, and the pressure in the reactor was adjusted to a temperature of 250 ° C. The amount was gradually decreased, and after 70 minutes, the pressure was reduced to 1.2 hPa or less. The polycondensation reaction was carried out for about 8 hours with stirring under these conditions, and the strands were discharged in a conventional manner to form chips.

Examples 2-5, Comparative Examples 1-8
The polycondensation reaction was carried out in the same manner as in Example 1 except that the content of PTMG, the content of the crystal nucleating agent, and the content of the organophosphorus compound in the resin composition were changed to the values shown in Table 1. Then, it was discharged into a strand shape by a conventional method to form a chip.

  Table 1 shows the characteristic values of the resin compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 8 and the evaluation results of the operability during chip formation. In Comparative Examples 2, 4 to 6, and 8, the chip could not be formed, but the viscosity, melting point, formula (1), and polymer composition were measured from the polymer mass obtained when the strands were discharged.

As is clear from Table 1, the polyester elastomer resin compositions of Examples 1 to 5 have a low melting point, excellent flexibility and flame retardancy, and the formula (1) is 0.03 or more, which is a good crystal. It had performance. In addition, the operability in the chip forming process was also good.
On the other hand, since the resin composition of Comparative Example 1 had a low molecular weight of polyalkylene glycol, the resin composition of Comparative Example 3 had a low content of polyalkylene glycol, so both had high hardness and poor flexibility. there were. Since the resin composition of Comparative Example 2 had a high molecular weight of polyalkylene glycol, the resin composition of Comparative Example 4 had a high content of polyalkylene glycol, so both were poorly compatible and the value of formula (1) was also The resin composition of Comparative Example 4 had a melting point that was too low, both of which were inferior in operability in the chip forming process, and could not be chipped. Since the resin composition of Comparative Example 5 did not have a crystal nucleating agent, the value of the formula (1) was low, the operability in the chip forming process was inferior, and the chip could not be formed. Since the resin composition of Comparative Example 6 contained too much content of the crystal nucleating agent, the polymerizability was poor, the operability in the chip forming step was inferior, and the chip could not be formed. Since the resin composition of Comparative Example 7 contained too little organophosphorus compound, the LOI value was less than 23 and the flame retardancy was poor. Since the resin composition of Comparative Example 8 contained too much organic phosphorus compound, it became an amorphous polyester resin, and the melting point and the value of the formula (1) could not be measured. It was inferior and could not be chipped.

Example 6
In an esterification reaction can, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane (Irganox-1010 manufactured by Ciba Specialty Inc.) as a hindered phenolic antioxidant A polycondensation reaction was carried out in the same manner as in Example 1 except that 100 g was supplied, and the strands were discharged in a conventional manner to form chips.

Examples 7-12, Comparative Examples 9-16
In the same manner as in Example 6, except that the content of PTMG, the content of crystal nucleating agent, the content of organic phosphorus compound and the antioxidant in the resin composition were changed to the values shown in Table 2. A condensation reaction was performed, and the strands were discharged in a conventional manner to form chips.

  Table 2 shows the characteristic values of the resin compositions obtained in Examples 6 to 12 and Comparative Examples 9 to 16 and the evaluation results of the operability during chip formation. In Comparative Examples 10, 12 to 14, and 16, chips could not be formed, but the viscosity, melting point, formula (1), and polymer composition were measured from the polymer mass obtained when the strands were dispensed.

As is clear from Table 2, the polyester elastomer resin compositions of Examples 6 to 12 have a low melting point, excellent flexibility and flame retardancy, and contain an appropriate amount of an antioxidant. It was also excellent in stability. Moreover, (1) type | formula is 0.03 or more, it had favorable crystal performance, and the operativity in the chip formation process was also favorable.
On the other hand, since the resin composition of Comparative Example 9 had a low polyalkylene glycol molecular weight, the resin composition of Comparative Example 11 had a low polyalkylene glycol content, so both had high hardness and poor flexibility. there were. Since the resin composition of Comparative Example 10 had a high molecular weight of polyalkylene glycol, the resin composition of Comparative Example 12 had a high content of polyalkylene glycol, so both were poorly compatible and the value of formula (1) was also The resin composition of Comparative Example 12 had a melting point that was too low, both of which were inferior in operability in the chip forming process, and could not be formed into chips. Since the resin composition of Comparative Example 13 did not have a crystal nucleating agent, the value of the formula (1) was low, the operability in the chip forming process was inferior, and the chip could not be formed. Since the resin composition of Comparative Example 14 contained too much content of the crystal nucleating agent, the polymerizability was poor, the operability in the chip forming step was inferior, and the chip could not be formed. Since the resin composition of Comparative Example 15 contained too little organophosphorus compound, the LOI value was less than 23 and the flame retardancy was poor. Since the resin composition of Comparative Example 16 contained too much organophosphorus compound, it became an amorphous polyester resin, and the melting point and the value of the formula (1) could not be measured. It was inferior and could not be chipped.

Claims (3)

A polyalkylene glycol having a hard segment and an average molecular weight of 500 to 5000, a polyester comprising an organic phosphorus compound copolymerized from a dicarboxylic acid component mainly composed of terephthalic acid and a diol component mainly composed of 1,6-hexanediol. Is a polyester elastomer resin composition in which the proportion of the soft segment is 5 to 50% by mass, the melting point is 100 to 150 ° C., the phosphorus atom content is 2000 to 15000 ppm, and the crystal nucleating agent is 0 A polyester elastomer resin composition comprising 0.01 to 3.0% by mass and a Shore hardness of 20 to 60. The polyester elastomer resin composition according to claim 1, wherein a DSC curve showing temperature-fall crystallization determined from DSC satisfies the following formula (1).
b / a ≧ 0.03 (mW / mg · ° C.) (1)
Note that a is the temperature A1 (° C.) of the intersection between the tangent line and the baseline having the maximum inclination in the DSC curve indicating the temperature-falling crystallization, and the temperature A2 (° C.) of the intersection of the tangent line and the baseline having the minimum inclination. B) is the difference (B1-B2) between the baseline heat quantity B1 (mW) and the peak top heat quantity B2 (mW) at the peak top temperature (mg) The value divided by. The polyester elastomer resin composition of Claim 1 or 2 which contains 0.1-2.0 mass% of hindered phenolic antioxidant in a resin composition.