JPH062866B2 - Reinforced polyester resin composition with excellent impact strength - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a reinforced polyester resin composition having improved physical properties, particularly improved impact strength and excellent moldability in injection molding and the like. .

[Conventional technology]

Polyethylene terephthalate (hereinafter sometimes abbreviated as PET) or poly (1,4-butylene terephthalate) (hereinafter sometimes abbreviated as PBT) is excellent in heat resistance, chemical resistance, mechanical properties, and electrical properties. It is used in many industrial products such as, textiles and films. In particular, PET or PBT reinforced with an inorganic filler such as glass fiber has been remarkably improved in thermal properties and mechanical properties, and is therefore widely used in engineering plastics and the like in recent years.

However, PET or PBT reinforced with such a filler does not always have sufficient impact resistance of the molded product, and therefore, when the molded product is secondarily processed, the molded product is transported, or the molded product is used. There is often the problem of destruction.

Although various methods are known as means for improving the impact resistance of the filler-reinforced polyester resin, it is common to blend an elastic polymer into the filler-reinforced PET or PBT.

For example, JP-B-45-26223 discloses a copolymer of vinyl ester of saturated aliphatic monocarboxylic acid and α-olefin as an impact modifier for polyester resin. JP-B-45-26224 discloses a copolymer of an acrylic ester and a conjugated diene as an impact modifier for polyester resin. Japanese Examined Patent Publication (Kokoku) No. 45-26225 discloses an ionomer as an impact modifier for polyester resin. However, it cannot be said that the desired impact strength of the molded product obtained by the above method is sufficiently improved.

Various other methods are known for modifying the impact strength of filler-reinforced polyester resins. For example, JP-A-51-1
44452, JP 52-32045, JP 53-117049
Japanese Patent Laid-Open Publication No. 2003-242242 discloses a method of blending a polyester resin with a copolymer of α-olefin and α, β-unsaturated carboxylic acid glycidyl ester. In addition to this copolymer, a method of additionally using an ethylenic copolymer as a third component is disclosed in JP-A-58-17148 and JP-A-58-1.
Japanese Patent Laid-Open No. 57-92044 discloses a method of using polyphenylene sulfide in combination with Japanese Patent No. 7151.

It is hard to say that sufficient impact strength was obtained even with these methods.

Impact strength can be improved by blending an extremely large amount of elastic material with a filler-reinforced polyester resin (see, for example, Japanese Patent Publication No. 59-3).
No. 0742). However, blending a large amount of elastic material lowers the heat resistance and mechanical strength inherent in polyester.

It is known from JP-A-53-102360 to increase warpage resistance by adding PBT to PET-based filler-reinforced polyester. However, even if PBT is blended with PET-based filler-reinforced polyester, it is not possible to expect an increase in impact strength.

[Problems to be solved by the invention]

A first object of the present invention is to impart extremely high impact resistance while maintaining other good properties of the filler-reinforced polyester resin as an injection molding resin. Another object of the present invention is to improve molding processability such as injection molding of the filler-reinforced polyester resin composition.

[Means for solving problems]

The present inventors have made earnest studies as to obtain a filler-reinforced polyester resin having excellent impact resistance.
If an effective amount of ionomer, block copolyetherester elastomer, and a specific amount of PBT are blended, the synergistic effect of them will strengthen the filler and retain the original high heat resistance and mechanical strength of the conventional filler-reinforced P.
They have found that a polyester resin composition having an extremely high impact strength as compared with ET can be obtained, and reached the present invention.

That is, the present invention comprises (a) polyethylene terephthalate-based polyester (component (a)) 85 to 15 parts by weight (b) poly (1,4-butylene terephthalate) -based polyester (component (b)) 15 to 85 parts by weight (c) α, β-unsaturated carboxylic acid unit is 1 mol% or more 30
Mol% or less and at least 20 mol% of carboxyl groups
Exists as a monovalent metal salt of α-olefin and α, β-unsaturated carboxylic acid, and optionally a metal salt of a copolymer of a third vinyl comonomer (component (c)) and (d) ) Block copolyetherester elastomer ((d)
Component) (e) A fibrous filler is kneaded, and the total blending amount of the (c) component and the (d) component is 20 to 50 per 100 parts by weight of the total blending amount of the (a) component and the (b) component.
The blending amount of parts by weight and the component (e) is 10 to 150 parts by weight, and the ratio of the blending amount of the component (d) to the component (c) ((d) /
A resin composition having (c)) of 10 or less, which provides a resin composition having extremely high impact strength.

Surprisingly, the impact strength of the molded article is extremely high if the PET polyester blended with the fibrous filler is used in combination with a specific amount of PBT polyester and modified with the specific amounts of the above-mentioned components (c) and (d). In some cases, the notched Izod impact strength can reach 20 kg · cm / cm or more. This is far higher than the impact strength of the filler-reinforced PET type polyester or the filler-reinforced PBT type polyester modified with the components (c) and (d).

The existence of such a very remarkable synergistic effect is particularly surprising because what is usually expected by a skilled person in the art is that the impact strength gradually increases as the amount of PBT-based polyester added increases. Furthermore, surprisingly in the present invention, in addition to the original properties of polyester (for example, heat resistance and mechanical strength) being retained, the composition thus obtained is extremely excellent in molding processability such as injection molding. It is that you are. That is, it is possible to obtain an injection-molded article having good surface gloss and releasability as a PET resin composition even at a relatively low mold temperature.

The present invention will be described below.

The PET-based polyester used in the present invention is such that most of the constituent units are ethylene terephthalate units. Therefore, the PET polyester is the original PE
Other copolymerizable components may be contained within a range that does not impair the physical properties of T. Such copolymerizable components include aromatic dicarboxylic acids such as naphthalene dicarboxylic acid, adipic acid,
Aliphatic dicarboxylic acids such as sebacic acid, diethylene glycol, 1,4-butanediol, neopentyl glycol, 2-2-bis (4,4'-hydroxyphenyl (diol such as propane, polyethylene glycol, poly (tetramethylene oxide) Examples thereof include polyalkylene glycols such as glycols and oxycarboxylic acids such as p-oxybenzoic acid, etc. The content of these copolymerization components is usually within 20 mol%, 10 mol%, particularly 5 mol%.
It is better to blend in a smaller amount.

Further, the PET-based polyester is a copolymerization component of a trifunctional or higher functional compound such as trimethylolpropane, trimellitic acid, pyromellitic acid and the like, and a monofunctional compound such as lauric acid and the like within a range of being substantially linear. You may contain as. The blending amount of these is usually within the range of 1 mol% or less with respect to the acid component or the diol component.

Of these, the preferred polyester in the present invention is substantially polyethylene terephthalate.

The PET ester used in the present invention preferably has an intrinsic viscosity of 0.4 or more from the viewpoint of strength properties of the resulting molded product. The intrinsic viscosity here is 30% in a 1: 1 weight ratio of a phenol / tetrachloroethane mixed solvent.
It is a value measured at ° C.

The present invention is characterized in that a specific amount of poly (1,4-butylene terephthalate) type polyester is used in combination with the PET type polyester (component (a)). PET-based polyester (component (a)) and ionic copolymer (component (c)),
By combining a predetermined amount of PBT-based polyester (component (b)) in combination with the block copolyetherester elastomer (component (d)), the impact strength is as high as never expected. Indicates.

PBT-based polyester used in the present invention ((b)
Component) is such that most of the constitutional units consist of butylene terephthalate units. Therefore, the PBT-based polyester may contain a copolymerization component in a range that does not impair the original properties of PBT. Such copolymerizable components include aromatic dicarboxylic acids such as naphthalene dicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid and sebacic acid, diethylene glycol, ethylene glycol, neopentyl glycol, 2-2-bis (4,4 ′ -Hydroxyphenyl)
Examples thereof include diols such as propane, and oxycarboxylic acids such as p-oxybenzoic acid. These copolymerization components are usually within 20 mol%, preferably 10 mol%, particularly preferably less than 5 mol%.

Further, the above PBT-based polyester is copolymerized with a compound having three or more functional groups such as trimethylolpropane, trimellitic acid and pyromellitic acid, and a monofunctional compound such as lauric acid within a range of being substantially linear. It may be contained as a component. The blending amount of these is usually within the range of 1 mol% or less with respect to the acid component or the diol component.

Of these, the preferred polyester in the present invention is substantially polybutylene terephthalate.

The intrinsic viscosity of the PBT-based polyester used is at least 0.6, and preferably 0.8 d / g or more, when measured by the above method. The upper limit is not important, but generally about 1.5d
/ G. The intrinsic viscosity of the particularly preferred PBT polyester is 0.9 to 1.2 d / g.

The amount of the PBT-based polyester used is 15 to 85 parts by weight based on 85 to 15 parts by weight of the PET-based polyester (component (a)). When the amount is 15 parts by weight or less, the synergistic effect of using both polyesters is small, and when the amount is 85 parts by weight or more, the PBT polyester alone is modified with the ionic copolymer (component (c)) and the block copolyetherester elastomer (component (d)). Only the impact resistance of the quality is obtained. A particularly preferred amount of PBT-based polyester used is 30 to 70 parts by weight.

In the present invention, a metal salt of a copolymer of α-olefin and α, β-unsaturated carboxylic acid and optionally a third vinyl monomer (hereinafter sometimes referred to as an ionic copolymer) is added to the polyester. To be The α-olefin which constitutes the ionic copolymer is ethylene, propylene, etc., and the α, β-unsaturated carboxylic acid is acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, etc. Ethyl acrylate, vinyl acetate and the like are preferable as the vinyl monomer. 1 to 3
Valuable metals include sodium, potassium, calcium,
Aluminum and the like are exemplified, but alkali metal, particularly sodium is preferable.

These ionic copolymers include α-olefin and α, β-
It can be produced by copolymerizing an unsaturated carboxylic acid and optionally a vinyl monomer, and then substituting a part or all of the carboxylic acid with a metal salt. Another method for producing an ionic copolymer is α-olefin and optionally a third method.
There is a method in which an α, β-unsaturated carboxylic acid is graft-polymerized to the copolymer with the vinyl monomer, and then the metal salt is substituted. Still another production method is to copolymerize α-olefin with α, β-unsaturated carboxylic acid ester and optionally a third vinyl monomer, and then saponify the carboxylic acid ester moiety and then replace it with a metal salt. There is also a manufacturing method. Although the ionic copolymer obtained by any method is adopted in the present invention, among these ionic copolymers, those particularly preferably used in the present invention are ethylene and acrylic acid or An alkali metal salt of a copolymer of ethylene and methacrylic acid, especially a sodium salt.

Such ionic copolymers are available from many sources. For example, it is sold under the trade name of Himilan by Mitsui Deupon Polychemicals.

In the above ionic copolymer, it is necessary that the carboxylic acid unit (including the salt form) occupy in the copolymer is 1 mol% or more and 30 mol% or less of all the copolymer units. When it is less than 1 mol%, the effect of the present invention, that is, the impact resistance of the polyester resin is not sufficiently improved. If it exceeds 30 mol%, the ionic copolymer cannot be sufficiently kneaded with the polyester in a short time in the molten state.
A more preferable range of the carboxylic acid unit ratio in the ionic copolymer used in the present invention is 2 mol% or more and 10 mol% or less.

In the present invention, the ionic copolymer need not have all the carboxyl groups present neutralized by metal ions, but at least 20 mol% of all carboxyl groups
Must be neutralized by metal ions. If the neutralization rate is less than 20 mol%, the effect of the present invention that the impact resistance of the polyester resin is improved cannot be sufficiently obtained. The preferable neutralization rate is 40% or more, and particularly 60 mol% or more.

The neutralization rate is measured by infrared spectrum analysis of the copolymer. That is, νc = 0 absorption intensity of a carboxyl group formed into a salt and νc = 0 of an unneutralized carboxylic acid carboxyl group.
It can be measured by the ratio with the absorption intensity.

In the present invention, the ionic copolymer is used in combination with the block copolyetherester elastomer.

The block copolyetherester elastomer of component (d) used in the present invention is composed of a polyester having 60 mol% or more of polyalkylene terephthalate and a poly (alkylene oxide) glycol having a molecular weight of 400 to 6000, and The poly (alkylene oxide) glycol component is contained in an amount of 10 to 80% by weight of the elastomer. The polyalkylene terephthalate constituting the hard segment of the block copolyetherester elastomer is a polymer having terephthalic acid as a main acidic component and an aliphatic glycol having 2 to 10 carbon atoms as a main diol component. Alternatively, a glycol obtained by copolymerizing glycols other than the aliphatic glycol having 2 to 10 carbon atoms up to 40 mol% in total may be used. Examples of the copolymerizable components include adipic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, phthalic acid,
Aliphatic, alicyclic or aromatic dicarboxylic acids such as isophthalic acid and naphthalenedicarboxylic acid; neopentyl glycol, 1,4-cyclohexanedimethanol, 1,4-
Mention may be made of aliphatic, cycloaliphatic or aromatic diols such as cyclohexanediethanol, 1,4 benzenedimethanol, 1,4-benzenediethanol and the like. In addition, oxy acids such as p-oxybenzoic acid and p-hydroxyethoxybenzoic acid can also be copolymerized.

Examples of the poly (alkylene oxide) glycol constituting the soft segment with the other component of the block copolyetherester elastomer include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (tetramethyloxide) glycol, etc. Single glycols; random or block copolymerized polyglycol of ethylene oxide and propylene oxide, tetrahydrofuran or random or block copolymerized polyglycol of tetrahydrofuran and 2,2-dimethyloxetane, and tetrahydrofuran
Copolymerized glycols such as polyglycol which is random or block copolymerized with 2,2-dimethyloxetane; and a mixture of two or more of the above glycols.

The number average molecular weight of the poly (alkylene oxide) glycol in the present invention is preferably 400 to 6000, more preferably 5
If the molecular weight is too large, the poly (alkylene oxide) glycol unit itself becomes crystalline and does not contribute to the improvement of impact resistance and abrasion resistance. Conversely, the molecular weight is 400 or less. However, similarly, it does not contribute to the improvement of impact resistance and wear resistance.

The content of poly (alkylene oxide) glycol in the block copolyetherester elastomer is 10 to 80%, preferably 15 to 70% of the weight of the elastomer.
Need to be.

If it is 80% by weight or more, the properties of the hard segment of the elastomer are almost disappeared and the compatibility with the PET-based polyester or PBT-based polyester becomes poor. On the other hand, when the amount is 10% by weight or less, the poly (alkylene oxide) glycol unit is small, so that the elastic modulus is lowered and the impact resistance is not improved.

A preferred specific example of the block copolyetherester elastomer of the component (d) in the present invention is a polyester in which 60 mol% or more of the polyester component (hard segment component) is polybutylene terephthalate, and the polyether component (soft segment component). An elastomer is a polyether glycol composed of poly (tetramethylene oxide) glycol.
Generally, the block copolyetherester elastomer of component (d) in the present invention is excellent in miscibility with PBT. Among them, the elastomer composed of the above-mentioned components is miscible with the modified PET-based polyester and PBT. Is very good.

The block copolyetherester elastomer of the present invention is manufactured by a conventional manufacturing method. For example, a method for directly esterifying terephthalic acid, a low molecular weight diol and a poly (alkylene oxide) glycol.
Any method of transesterifying dialkyl terephthalate and low molecular weight diol and then adding poly (alkylene oxide) glycol to carry out polycondensation may be adopted. In producing the elastomer, a catalyst for promoting each reaction, various stabilizers, modifiers, pigments and the like can be used if necessary.

There are numerous sources of such block copolyetherester elastomers. For example, it is sold by Toyobo Co., Ltd. under the trade name of Perprene.

The block copolyetherester elastomer ((d) component) is used in combination with the ionic copolymer, but the mixing ratio is such that the (d) component does not exceed 10 parts by weight of the (c) component mixing part. is there. If the number of parts of the component (c) is too small, the improvement in impact resistance, which is the object of the present invention, cannot be achieved.
As long as the high impact resistance, which is one of the objects of the present invention, can be maintained, a larger blending ratio of the component (d) to the component (c) is preferable for the melt fluidity of the composition. The ratio ((d) / (c)) of the blending amount of component (d) to component (c) is preferably 0.5-
The range is 5.

The total amount of the ionic copolymer (c) and the block copolyetherester elastomer (d) blended is 1 in total of the PET polyester (a) and the PBT polyester (b).
It is 20 to 50 parts by weight with respect to 00 parts by weight. If it is less than 20 parts by weight, the object of the present invention of improving the impact resistance of the filler-reinforced PET polyester resin cannot be sufficiently achieved. On the other hand, if the amount exceeds 50 parts by weight, the mechanical properties of the molded article made of the composition of the present invention are different from those inherent in the filler-reinforced PET polyester resin and, for example, the rigidity of the molded article is lost. Particularly preferred total amount of the ionic copolymer (c) and the block copolyetherester elastomer (d) is P
It is 25 to 40 parts by weight based on 100 parts by weight of the total amount of the ET polyester (a) and the PBT polyester (b) compounded.

As the fibrous filler used in the present invention, glass fiber,
Examples thereof include carbon fibers, graphite fibers, metal fibers, silicon carbide fibers, asbestos, wollastonite, inorganic fibers such as fibrous potassium titanate, whiskers, and various organic fibers. The preferred fibrous filler is glass fiber, but is not particularly limited, and depending on various purposes such as strengthening mechanical properties, imparting heat resistance, imparting conductivity, improving frictional properties, and improving flame retardancy. Used. Two or more kinds of these fibrous fillers can be mixed and used. The amount of the fibrous filler compounded is 10 to 150 parts by weight with respect to 100 parts by weight of the thermoplastic polyester (the total of the components (a) and (b)).
It is preferably 10 to 120 parts by weight. When the blending amount is 10 parts by weight or less, not only the original mechanical strength and heat resistance that are reinforced by PET cannot be obtained, but also the effect of improving the impact resistance, which is the object of the present invention, becomes small. If the amount is 150 parts by weight or more, the fluidity during molding tends to be impaired and the surface gloss of the molded product tends to be impaired, which is not preferable.

The fibrous filler can be blended as it is, but in order to enhance the affinity and adhesiveness with the polyester resin, the mechanical strength can be further improved by using the one that has been surface treated with an appropriate surface treatment agent. Be improved. Various known surface treatment agents can be used in the present invention, and examples thereof include silane-based, titanate-based, and epoxy-based surface treatment agents.

The above-mentioned polyester, ionic copolymer and block copolyetherester elastomer are usually obtained in the form of powder or particles (pellets, chips). The desired polyester molded article can be produced by simply melt-mixing these and fibrous fillers, but once the mixture is melt-kneaded to form a pellet or chip, the pellet or chip can be molded from this pellet or chip. The target molded article can also be melt-molded. Therefore, in the present invention, the mixture of the polyester, the ionic copolymer, the block copolyetherester elastomer and the fibrous filler is not limited to those in which the respective powders or particles and the fibrous filler are simply mixed. Also, those obtained by melting and kneading both are included.

When blending the ionic copolymer and the block copolyetherester elastomer and the filler with the polyester or melt-forming the mixture of the polyester, the ionic copolymer and the block copolyetherester elastomer and the filler, usually, Various additives added to the polyester, for example, a colorant, a release agent, an antioxidant, an ultraviolet stabilizer, a flame retardant and the like can be added.

The composition of the present invention can be manufactured into various molded articles by melt molding methods such as extrusion molding and injection molding. As a molded product obtained by extrusion molding, a molded product having an arbitrary shape such as a rod shape, a sheet shape, a plate shape, a tube shape or a pipe shape can be manufactured.
Further, by cutting such an extrusion-molded product, a melt molding material in the form of chips or particles such as chips, pellets or the like can be obtained. Further, according to the injection molding method, an arbitrary shape can be manufactured depending on the shape of the mold. The molded product obtained by any of the molding methods can be easily made into a desired final molded product by secondary molding such as blow molding, drawing molding or vacuum molding. And, all of these various molded products can obtain extremely high impact strength.

As described above, the composition of the present invention gives a molded article having extremely high impact strength, which has not been expected with the conventional filler-reinforced PET-based polyester resin, without deteriorating other physical properties. The contribution is extremely large.

Further, since the composition of the present invention is a PET resin having a temperature of around 100 ° C., the polyester is sufficiently crystallized even when injection-molded in a mold having a relatively low temperature, and a molded product having good releasability and excellent surface properties is obtained. It can be said that the resin is excellent in moldability.

Further, in addition, thermoplastic polyesters such as PET and PBT are generally easily hydrolyzed at the time of heating and need to be sufficiently dried before molding. The composition of the present invention is insensitive to moisture, and predrying conditions before molding are preferable. It also has the advantage of being able to alleviate.

Hereinafter, the present invention will be described with reference to examples. All parts in the examples are by weight unless otherwise specified.

Reference Example A (Synthesis Example of Block Copolyether Ester) Dimethyl terephthalate 136.0 parts, number average molecular weight about 1
000 poly (tetramethylene oxide) glycol 1
52.1 parts and 94.5 parts of 1,4-butanediol were charged into a reaction vessel equipped with a stirrer together with 0.10 part of a titanium tetrabutoxide catalyst and heated at 210 ° C. for 2 hours to distill off methanol. After distilling out almost the theoretical amount of methanol, 4.0 parts of Irganox 1010 = trade name (antioxidant, Ciba-Geigy Co., Ltd.) was added to the reaction mixture, and the temperature was raised to 25.
Raise the temperature to 0 ° C and gradually increase the system pressure to 0.3 mm over 1 hour.
It was lowered to Hg. Polymerization was carried out for 2 hours under these conditions. The polymer obtained had an intrinsic viscosity of 0.9.

Examples 1 to 9 and Comparative Examples 1 to 6 To a predetermined amount of PET having an intrinsic viscosity of 0.68 which was sufficiently dried in a hot air dryer in advance, PBT having an intrinsic viscosity of 0.85 and ethylene / methacryl as an ionic copolymer. Sodium salt of acid copolymer (methacrylic acid (salt) unit content 7
mol% neutralization ratio 80%) and a polymer prepared in Reference Example A as a block copolyetherester elastomer, and 3 mm long convergent strands (made by Nitto Boseki) as glass fibers and Phosph as an antioxidant.
ite168 = Trade name (Ciba Geigy) is blended in a predetermined amount as shown in Table 1 and premixed, and then charged into a hopper of a 40 mmφ extruder (8VSE-40-28 manufactured by Osaka Seiki Kogyo Co., Ltd.) and the cylinder temperature 250-275-27
5-275 ° C (from hopper side), adapter temperature 26
A strand was obtained by extruding while melt-kneading at 5 ° C. and a die temperature of 265 ° C. This was cut into a pellet. Then, the pellet is heated to a cylinder temperature of 240-260-280.
C., die temperature 280.degree. C., mold temperature 130.degree. C. injection molding machine (V-15-75 manufactured by Nikko Ankelberg Ltd.).
A test piece having a thickness of 3 mm was molded by a mold. Impact strength of the obtained molded product (Izod method, with notch, JIS K 711
0) and tensile strength (based on JIS K7113)
Are shown in Table 1.

As can be seen from the examples in Table 1, the PBT content is PET6.
The impact resistance of the composition was maximized at about 40 parts with respect to 0 part, and was extremely high as a filler-reinforced PET resin.

This synergistic effect was difficult to be seen when the compounding amount of PBT in the total amount of 100 parts of PET and PBT was less than 15 parts (Comparative Example 1). In addition, when the content of PBT is 85 parts or more, when the PBT is in a large excess amount, the impact strength is glass fiber reinforced P.
It decreased toward the value only when BT alone was modified with an ionic copolymer (Comparative Examples 5 and 6).

If the total amount of the ionic copolymer and the block copolyetherester is 20 parts or less with respect to 100 parts of the total polyester resin of PET and PBT, as shown in Comparative Example 3, the optimum amount of PBT is shown. Even so, improvement of impact resistance was not expected.

Even if the total amount of the ionic copolymer and the block copolyether ester is 30 parts per 100 parts of the total polyester resin, the mixing ratio of the ionic copolymer to the block copolyether ester is 1 / If it is less than 10, high impact resistance cannot be obtained (Comparative Example 2). A high impact resistance can be expected even if almost all of the ionic copolymer is made to have such a large proportion (Example 4). It is desirable to use both in combination because of the fluidity of the resin.

When the content of the glass fiber is less than 10 parts with respect to 100 parts of the total polyester resin, the impact strength becomes low as shown in Comparative Example 4.

Example 10 Sodium salt of ethylene / acrylic acid / ethyl acrylate copolymer (acrylic acid (salt) as ionic copolymer
Unit content 5 mol%, ethyl acrylate unit content 1 mol
%, Neutralization rate 100%), and 15 parts of block copolyetherester elastomer were used to prepare a composition under the same conditions as in Example 2 and molded to obtain a test piece.
Table 1 shows the impact strength and measurement results.

Example 11 Sodium salt of ethylene / acrylic acid / ethyl acrylate copolymer (acrylic acid (salt) as ionic copolymer
Unit content 3 mol%, ethyl acrylate unit content 3 mol
%, Neutralization rate 100%), and 10 parts of a block copolyetherester elastomer were used to prepare a composition under the same conditions as in Example 3, followed by molding to obtain a test piece.
The impact strength measurement results are shown in Table 1.

Example 12 Sodium salt of ethylene / acrylic acid copolymer as an ionic copolymer (acrylic acid (salt) unit content 6 mol
%, Neutralization rate 30%) and 10 parts of block copolyetherester elastomer were used to prepare and mold a composition under the same conditions as in Example 3 to obtain a test piece. The impact strength measurement results are shown in Table 1.

Comparative Examples 7 and 8 A composition was prepared and molded under the same conditions as in Example 10 except that the content of the acrylate unit in the ionic copolymer was changed as shown in Table 1 to obtain a test piece. As shown in Table 1, it was confirmed that when the acrylate unit content was 1 mol% or less, the impact resistance was not improved, and when it was 30 mol% or more, molding could not be performed.

Comparative Example 9 A composition was prepared under the same conditions as in Example 9 except that a partially neutralized ethylene / acrylic acid / ethyl acrylate copolymer having an acrylic acid neutralization ratio of 20% or less was used as the ionic copolymer. Was prepared and molded to obtain a test piece. Also in this case, as shown in Table 1, no significant improvement in the rub impact strength was observed.

Example 13 In Example 3, the mold temperature in injection molding was 110 ° C.
Then, an experiment was conducted in exactly the same manner as in Example 3 except that the injection molding was carried out using a mold whose temperature was controlled so that the oil circulation temperature could be controlled. Also in this case, a molded product having good releasability and excellent surface gloss was obtained, and the crystallinity of the polyester reached 24% according to the X-ray method. Also, the impact resistance of the molded product is 2
2 kg · cm / cm (Izotsu (with notch)), 13
The value was equivalent to that obtained by molding at a mold temperature as high as 0 ° C.

Example 14 and Comparative Example 10 A molded piece was obtained by the same method as in Example 3 except that the PET which was not dried and contained 0.1% of water was used. The impact strength was 16 kg · cm / cm (Izot (with notch)), and the retention rate of 73% was obtained as compared with that of Example 3 using sufficiently dried PET. For comparison, a composition consisting of PET containing 0.1% water and glass fiber was injection-molded in the same manner as in Example 3 and the impact resistance was measured, and it was compared with the case where absolutely dried PET was used. The retention rate was 55%. From these examples, it was confirmed that the composition of the present invention retains relatively excellent physical properties even when molded using PET in a water-containing state.

Examples 15-18 and Comparative Examples 11 and 12 In Examples 1-9, the average molecular weight of 10 was used instead of PET.
Polyethylene terephthalate polyester copolymerized with polyethylene glycol of 00 as a glycol component (copolymerization amount is 10 parts by weight with respect to 100 parts by weight of ethylene terephthalate component, that is, the ratio of polyethylene glycol to all glycol components is 1.9 mol%). Molded pieces were obtained in the same manner as in Examples 1 to 9 except for the above. The impact strength is shown in Table 2.

Example 19 In Example 18, the mold temperature in injection molding was 90 ° C.
An experiment was conducted in exactly the same manner as in Example 18 except that injection molding was performed using a mold whose temperature was controlled by water circulation. Also in this case, a molded product having good releasability and excellent surface gloss was obtained, and the crystallinity of the polyester reached 21%. The impact resistance of the molded product was 22 kg.cm/cm (Izod (with notch)), which was equivalent to that obtained by molding at a mold temperature as high as 130 ° C.

〔The invention's effect〕

As described above in the examples, the present invention is a polyester resin modified with extremely high impact strength which is not expected with the conventional filler-reinforced PET polyester resin without deteriorating other physical properties. It is intended to provide a composition.
Further, by using the composition of the present invention, an injection-molded article having excellent mold releasability and excellent surface gloss can be obtained even if a mold having a low mold temperature of about 100 ° C. is used as PET. Also P
Generally, ET is easily hydrolyzed when heated and needs to be sufficiently dried before molding. However, the composition of the present invention is relatively insensitive to moisture and has a feature that predrying conditions before molding can be relaxed.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Okuno Kenji Okuno 1621 Sakurazu, Kurashiki City, Okayama Prefecture Kuraray Co., Ltd. (56) References JP-A-53-81530 (JP, A) JP-A-57-63354 (JP) , A)

Claims (7)

[Claims] 1. (a) Polyethylene terephthalate type polyester (component (a)) 85 to 15 parts by weight (b) Poly (1,4-butylene terephthalate) type polyester (component (b)) 15 to 85 parts by weight (c ) α, β-unsaturated carboxylic acid unit is 1 mol% or more 3
0 mol% or less and at least 20 mol% of carboxyl groups are present as a metal salt having a valence of 1 to 3, α-olefin and α, β-unsaturated carboxylic acid, if necessary, and a copolymerization with a third vinyl monomer. Combined metal salt ((c) component) and (d) block copolyetherester elastomer ((d)
Ingredients) (e) Fibrous filler is kneaded, and the total blending amount of component (a) and component (b) is 100
The total amount of the components (c) and (d) is 20 to 5 parts by weight.
0 parts by weight and 10 to 150 parts by weight of the component (e), and the ratio of the component (d) to the component (c) ((d)
/ (C)) is 10 or less. 2. The resin composition according to claim 1, wherein the component (a) is polyethylene terephthalate. 3. The resin composition according to claim 1, wherein the component (c) is an alkali metal salt of a copolymer of ethylene and acrylic acid or methacrylic acid. 4. The resin composition according to claim 1, wherein the monovalent to trivalent metal constituting the component (c) is sodium. 5. A block copolymer of a polyester and poly (tetramethylene oxide) glycol, wherein the block copolyetherester elastomer (component (d)) comprises 60% by mole or more of poly (1,4-butylene terephthalate). The resin composition according to claim 1, wherein: 6. The resin composition according to claim 1, wherein the component (b) is poly (1,4-butylene terephthalate). 7. The resin composition according to claim 1, wherein the component (e) is glass fiber.