JPH0841301A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide a satd. polyester resin compsn. which can provide a molding having a good balance between the impact resistance and the bending modulus of elasticity. CONSTITUTION:A thermoplastic resin compsn. comprising (A) 50 to 99wt.% satd. polyester resin and (B) 50 to 1wt.% modified resin prepd. by melt-kneading 100 pts.wt. hydrogenation product of a block copolymer of an arom. vinyl compd. with a conjugated diene compd., 0.01 to 50 pts.wt. hydroxylated. alpha,beta- unsatd. carboxylic ester and 0.01 to 50 pts.wt. arom. vinyl compd. in the presence of a free-radical generator.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic resin composition which has improved compatibility between a thermoplastic elastomer and a saturated polyester resin, has an excellent balance of rigidity and impact strength, and gives a molded article having an excellent appearance. Regarding things.

[0002]

2. Description of the Related Art Saturated polyester resins represented by polyethylene terephthalate and polybutylene terephthalate are used in the field of electric parts and automobile parts as engineered plastics having excellent heat resistance, chemical resistance and electric characteristics. However, there is a drawback in that the impact strength is remarkably reduced by making the notch.

Then, in order to improve the impact strength, Japanese Patent Laid-Open No.
No. 0-130642 discloses saturated polyester resin 10
A resin composition containing 1 to 50 parts by weight of a hydrogenated aromatic vinyl compound-conjugated diene compound block copolymer with respect to 0 parts by weight is disclosed. Also, JP-A-61-126164
The publication proposes a resin composition containing 100 parts by weight of an aromatic polyester resin and 1 to 100 parts by weight of a hydrogenated styrene-butadiene block copolymer modified with maleic anhydride.

The former composition cannot be said to be sufficient for improving the impact resistance of a notched molded article, and the latter composition improves the impact resistance but decreases the rigidity (flexural modulus). There are drawbacks.

[0005]

DISCLOSURE OF THE INVENTION The present invention improves the compatibility between a saturated polyester resin and a thermoplastic elastomer, and provides a molded article excellent in impact strength and appearance without lowering rigidity, moldability and the like. It is an object of the present invention to provide a thermoplastic resin composition capable of giving

[0006]

The present invention provides (A) 50 to 99% by weight of a saturated polyester resin, and (B) 100 parts by weight of a hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound. On the other hand, in the presence of a radical generator, a hydroxyl group-containing α, β-unsaturated carboxylic acid ester 0.
Modified resin 50 to 1% by weight obtained by melt-kneading 01 to 50 parts by weight and aromatic vinyl compound 0.1 to 50 parts by weight
The present invention provides a thermoplastic resin composition containing:

[0007]

The carboxyl group and / or ester group of the saturated polyester resin of the component (A) reacts with the hydroxyl group of the elastomer of the component (B) to improve the compatibility of the two, and at the same time, the fragrance in the component (B). A polymer based on a group vinyl compound improves the rigidity of the molded body.

(Outline of the Invention) (A) Saturated Polyester Resin As the saturated polyester resin, various saturated polyester resins can be used. For example, a thermoplastic polyester resin produced by condensing a dicarboxylic acid or a lower alkyl ester thereof, an acid halide or an acid anhydride derivative and a glycol according to a usual method can be mentioned.

Specific examples of the aromatic or aliphatic dicarboxylic acid suitable for producing the polyester resin include:
Oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, p, p'-dicarboxydiphenyl sulfone, p-carboxyphenoxyacetic acid, p-carboxyphenoxy acid Propionic acid, p-carboxyphenoxybutyric acid, p-carboxyphenoxyvaleric acid, 2,6-
Examples thereof include naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid and the like, or a mixture of these carboxylic acids.

Specific examples of glycols have 2 to 2 carbon atoms.
12 linear alkylene glycols such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc .; aromatic glycols such as pyrocatechol, resorcinol, hydroquinone, bisphenol A; alicyclic rings Examples of the formula glycol include cyclohexanedimethanol and the like; or alkyl-substituted derivatives of these compounds.

Suitable thermoplastic polyester resins include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate and poly (1,4-
Cyclohexane dimethylene terephthalate). Liquid crystalline polyesters such as X7G manufactured by Eastman Kodak Co., Vectra manufactured by Hoechst Celanese Co., Ltd., and Econol manufactured by Sumitomo Chemical Co., Ltd. are also preferable. These can be used alone or in combination of two or more.

The thermoplastic polyester resin as the component (A) contributes to improving the heat resistance, rigidity and appearance of the molded product. (B) Modified elastomer The modified elastomer of the component (B) is a hydrogenated product 1 of a block copolymer of an aromatic vinyl compound and a conjugated diene compound.
Obtained by melt-kneading 0.01 to 50 parts by weight of a hydroxyl group-containing α, β-unsaturated carboxylic acid ester and 0.1 to 50 parts by weight of an aromatic vinyl compound in an amount of 00 parts by weight in the presence of a radical generator. It is a modified resin.

(I) Hydrogenated Product of Block Copolymer of Aromatic Vinyl Compound and Conjugated Diene Compound The hydrogenated product of the block copolymer of an aromatic vinyl compound and a conjugated diene compound is at least 1 At least 80% of the aliphatic double bonds based on the conjugated diene compound of the block copolymer consisting of a polymer block mainly containing one aromatic vinyl compound and a polymer block mainly containing at least one conjugated diene compound Is a hydrogenated block copolymer obtained by hydrogenating.

As the aromatic vinyl compound, for example, styrene, α-methylstyrene, α-methoxystyrene,
Methylstyrene, dimethylstyrene, 2,4,6-trimethylstyrene, chlorostyrene, dichlorostyrene,
Examples thereof include bromostyrene, nitrostyrene, chloromethylstyrene, cyanostyrene, t-butylstyrene, vinylnaphthalene and the like, of which styrene is preferred. These can be used alone or in combination of two or more.

As the conjugated diene compound, butadiene,
Examples include isoprene, 1,3-pentadiene and 2,3-dimethyl-1,3-butadiene. Of these, butadiene, isoprene and combinations thereof are preferable.
The method for producing this block copolymer is described in, for example, Japanese Patent Publication No.
According to the method described in 0-23798, a lithium catalyst can be used for synthesis in an inert solvent.

In the polymer block mainly composed of the conjugated diene compound, the microstructure in the block can be arbitrarily selected. For example, in the polybutadiene block, the 1,2-vinyl bond structure is 5 to 65%, preferably 10 to 50%. The molecular structure of the block copolymer may be linear, branched, radial, or any combination thereof.

The preferred block copolymer is styrene-
Butadiene block copolymer, styrene-butadiene-
They are a styrene block copolymer, a butadiene-styrene-block copolymer, a styrene-isoprene block copolymer, and a styrene-isoprene-styrene block copolymer. As a method for producing a hydrogenated block copolymer,
For example, Japanese Patent Publication No. 42-8704 and Japanese Patent Publication No. 43-6.
It can be obtained by the method described in Japanese Patent No. 636. In particular, a hydrogenated block copolymer synthesized using a titanium-based hydrogenation catalyst that exhibits excellent heat resistance and heat deterioration resistance of the obtained hydrogenated block copolymer is most preferable. 59-133203, JP-A-60-7.
According to the method described in Japanese Patent Publication No. 9005, it can be obtained by hydrogenating a block copolymer having the above structure in the presence of a titanium-based hydrogenation catalyst in an inert solvent. At that time, at least 80% of the aliphatic double bond based on the conjugated diene of the aromatic vinyl compound-conjugated diene compound block copolymer was hydrogenated, and the polymer block mainly composed of the conjugated diene compound was morphologically modified to an olefin type compound. It needs to be converted to a polymer. The amount of non-hydrogenated aliphatic double bonds contained in this hydrogenated block copolymer can be easily known by infrared spectroscopy, nuclear magnetic resonance method or the like.
The content of the aromatic vinyl block is 10 by weight.
-50%, preferably 20-40%.

The number average molecular weight of the hydrogenated block copolymer is 10,000 to 200,000, preferably 20,000 to 150,000, and more preferably 30,000 to 100,000. Such a hydrogenated block copolymer is available from Shell Chemical Co., Ltd. under the grade name of Kraton G1652 and from Kuraray Co., Ltd. under the grade name of Septon 2007.

(Ii) Hydroxyl group-containing α, β-unsaturated carboxylic acid ester compound The α, β-unsaturated carboxylic acid ester compound having a hydroxyl group used for modifying the hydrogenated block copolymer is, for example, 2- Hydroxyethyl methacrylate, 2
-Hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2,3-dihydroxypropyl methacrylate,
2,3-dihydroxypropyl acrylate, 2-hydroxymethyl-3-hydroxypropyl methacrylate, 2-hydroxymethyl-3-hydroxypropyl acrylate, 2,2-dihydroxymethyl-3-hydroxypropyl methacrylate, 2,2-dihydroxymethyl- 3-hydroxypropyl acrylate, carbon number 4
~ 40 ethylene glycol or propylene glycol oligomer methacrylic acid or acrylic acid ester, bis (2-hydroxyethyl) malate,
Bis (2-hydroxyethyl) fumarate, bis (2-
Hydroxypropyl) malate, bis (2-hydroxypropyl) fumarate, bis (2,3-dihydroxypropyl) malate, bis (2,3-dihydroxypropyl) fumarate, bis (2-hydroxymethyl-3-hydroxypropyl) malate, Bis (2-hydroxymethyl-3-hydroxypropyl) fumarate, bis (2,2-dihydroxymethyl-3-hydroxypropyl) malate, bis (2,2-dihydroxymethyl-3)
-Hydroxypropyl) fumarate, maleic acid or fumaric acid ester of an oligomer of ethylene glycol or propylene glycol having 4 to 40 carbon atoms, and the like. The maleic acid or fumaric acid ester is not limited to the one in which two carboxyl groups are esterified with two co-hydroxyalkyl groups as described above, but the one in which only one is esterified has the same hydroxyl group-containing α. , Β-unsaturated carboxylic acid ester compound.

The above α, β-unsaturated carboxylic acid ester compounds having a hydroxyl group can be used alone or in combination of two or more kinds. Among these, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate and the like are preferable. The hydroxyl group-containing α, β-unsaturated carboxylic acid ester compound is used in an amount of 0.01 to 5 with respect to 100 parts by weight of the hydrogenated block copolymer.
It is used in an amount of 0 part by weight, preferably 1 to 20 parts by weight. If it is less than 0.01 parts by weight, the effect of improving the compatibility is small, and if it exceeds 50 parts by weight, gelling causes a problem in molding processability, and the impact resistance and appearance of the molded product deteriorate.

(Iii) Aromatic Vinyl Compound In order to increase the graft amount of the above α, β-unsaturated carboxylic acid ester compound having a hydroxyl group onto the hydrogenated block copolymer, and to increase the rigidity of the resulting molded article. Examples of the aromatic vinyl compound used include styrene and α
-Methylstyrene, α-methoxystyrene, methylstyrene, dimethylstyrene, 2,4,6-trimethylstyrene, chlorostyrene, dichlorostyrene, bromostyrene, nitrostyrene, chloromethylstyrene, cyanostyrene, t-butylstyrene, vinylnaphthalene. And so on. Of these, styrene, α-methylstyrene and methylstyrene are preferable. These can be used alone or in combination of two or more.

The amount of the aromatic vinyl compound added is 0.1 to 50 parts by weight, based on 100 parts by weight of the hydrogenated block copolymer.
It is preferably 1 to 20 parts by weight. If the amount is less than 0.1 part by weight, the amount of the hydroxyl group-containing α, β-unsaturated carboxylic acid ester compound grafted onto the hydrogenated block copolymer cannot be increased. Further, if the amount exceeds 50 parts by weight, the impact resistance of the obtained molded product is impaired.

The ratio of the addition amount of the hydroxyl group-containing α, β-unsaturated carboxylic acid ester compound to the aromatic vinyl compound can be in the range of 1:99 to 90:10 by weight, preferably 20: The range is 80 to 80:20. (Iv) Radical Generator As a radical generator, t-butyl hydroperoxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, benzoyl peroxide, dicumyl peroxide, 1, 3-bis (t-
Butyl peroxy-isopropyl) benzene, t-butyl peroxybenzoate, dibutyl peroxide, methyl ethyl ketone peroxide, potassium peroxide, organic and inorganic peroxides such as hydrogen peroxide, 2,2'-azobisisobutyronitrile Azo compounds such as 2-2'-azobis (isobutylamide) dihalide, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], azodi-t-butane, carbon such as dicumyl A radical generator or the like can be used. These radical generators can be appropriately selected in relation to the modifier and the reaction form. Further, two or more kinds can be used in combination. The amount of the radical generator used is in the range of 0.01 to 30 parts by weight, preferably 0.05 to 10 parts by weight, based on 100 parts by weight of the hydrogenated block copolymer.

(V) Modification conditions The apparatus used for melt-kneading is an extruder or a stirrer, specifically a Labo Plastomill, a single or twin-screw kneader, a horizontal twin-screw multi-disc device or a horizontal twin-screw surface renewal machine And a horizontal twin-screw stirrer, or a vertical stirrer such as a double helical ribbon stirrer.

The kneading temperature may be any temperature as long as the hydrogenated block copolymer is in a molten state, but it is preferably 150 to 250 ° C. or lower in order to prevent deterioration. The time is in the range of 0.01 to 10 minutes, preferably 0.1 to 5 minutes. Further, in order to remove the unreacted hydroxyl group-containing α, β-unsaturated carboxylic acid ester compound and the aromatic vinyl compound and prevent the deterioration of the resulting modified resin, it is preferable that the melt-kneading and granulation be performed under reduced pressure.

Hydroxyl group-containing α, β-unsaturated carboxylic acid ester compounds which are these modifiers and aromatic vinyl compounds,
And as a method for adding the radical generator, a method of dry blending with a hydrogenated aromatic vinyl compound-conjugated diene compound block copolymer and kneading at once, either a modifier or a radical initiator and hydrogenated aromatic vinyl Compound-
Examples thereof include a method of dry blending a conjugated diene compound block copolymer and adding the other during kneading, a method of adding a modifier and a radical initiator to a resin in a molten state. A small amount of an organic solvent such as xylene may be added to improve reaction efficiency and adjust viscosity during kneading.

Composition In the resin composition of the present invention, the saturated polyester resin as the component (A) is 50 to 99% by weight, preferably 70 to 95% by weight, and the modified resin as the component (B) is 1 to 50% by weight. %, Preferably 5 to 30% by weight. If the amount of the component (A) is less than 50% by weight or the amount of the component (B) exceeds 50% by weight, the resulting molded article has low flexural modulus and heat resistance. If component (A) exceeds 99% by weight, impact resistance is poor.

Additional Components The thermoplastic resin composition of the present invention may contain other components in addition to the above components (A) and (B). For example, a part of the modified resin of the component (B) may be replaced with an unmodified hydrogenated aromatic vinyl compound-conjugated diene compound block copolymer.

Further, an antioxidant, a weather resistance improver, a nucleating agent, a flame retardant, a slip agent, etc., a plasticizer, a fluidity improver, a release agent and the like can be used as additional components. Furthermore, it is possible to improve rigidity, heat resistance and the like by adding an organic / inorganic filler and a reinforcing agent. For practical use, various colorants and their dispersants can also be used. In addition, a small amount of other thermoplastic resin may be added. As the thermoplastic resin, for example, polyolefin,
Examples include polycarbonate, polyphenylene ether, polyamide, or a mixture thereof.

Method for preparing composition and molding method The method for obtaining the thermoplastic resin composition of the present invention is not particularly limited, such as a melting method, a solution method and a suspension method, but in practice, a method of melt kneading is used. Is preferred. As the melt-kneading method, a kneading method generally used for thermoplastic resins can be applied. For example, the powdery or granular components are uniformly mixed together with the additives described in the section of additional components, if necessary, using a Hengel mixer, ribbon blender, V-type blender, etc., and then uniaxial or multiaxial. Kneading extruder,
It can be kneaded with a roll, a Banbury mixer or the like.

The melting and kneading temperature of each component is 150
In the range of ℃ to 350 ℃, preferably 200 ℃ to 300
It is in the range of ° C. The molding method of the thermoplastic resin composition of the present invention is not particularly limited, a molding method generally used for thermoplastic resins, that is, injection molding,
Various molding methods such as blow molding, extrusion molding, thermoforming and press molding can be applied.

[0032]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Production Example 1 of Modified Resin Hydrogenated styrene-butadiene block copolymer (trade name: Clayton G1652 manufactured by Shell Chemical Co., Ltd .; hereinafter “G1652”)
3 kg, 2-hydroxyethyl methacrylate (hereinafter abbreviated as “HEMA”) 150 g, styrene monomer (hereinafter abbreviated as “SM”) 150 g, and 1,3-bis (t-butylperoxyisopropyl) benzene (chemical agent Akzo Product name “Perkadox 14”; hereinafter “P1
(Abbreviated as “4”) 6 g of the mixture was dry-blended and then, using a twin-screw extruder (trade name: TEX-30, manufactured by Japan Steel Works), a cylinder temperature of 160 ° C., a screw rotation speed of 200 rpm,
A modified resin was obtained by kneading under reduced pressure under the conditions of a discharge rate of 2 kg / hr and a vent pressure of 50 mmHg.

0.3 g of the modified resin thus obtained was dissolved in 50 ml of chloroform at room temperature and poured into 300 ml of methanol for precipitation. This precipitate was separated by filtration and dried under reduced pressure (normal temperature) to obtain a purified resin (modified resin-1). The amount of structural units based on HEMA contained in the modified resin-1 was determined by the following method, and was 0.60% by weight by IR method, N
It was 0.55% by weight by the MR method.

((Quantification method of HEMA)) Infrared spectroscopy (IR): The obtained purified resin was press-molded at 200 ° C. to form a sheet, and the IR spectrum was measured. The quantification was performed by a calibration curve using characteristic absorption of a carbonyl group at 1724 cm-1. Proton Nuclear Magnetic Resonance Spectroscopy (H-NMR): Purified Resin 3
0 to 50 mg of 130 in about 1 ml of o-dichlorobenzene
It melt | dissolved at (degreeC), a small amount of deuterated benzene was added, the sample was prepared, and H-NMR was measured. The quantification was performed by absorption of methylene bonded to a hydroxyl group (chemical shift: 3.9 ppm) and methylene bonded to an ester group (chemical shift: 4.2 ppm).

The value obtained by IR represents the graft addition amount of HEMA, and the value obtained by NMR represents the amount of HEMA having a hydroxyl group. Therefore,
The survival rate is

[0036]

[Equation 1]

Is calculated. Example 2 In Example 1, the amount of the radical generator P14 used was 6 g
Modified resin-2 was obtained in the same manner except that the amount was changed to 15 g.

Example 3 In Example 1, hydrogenated block copolymer G1652 was added to hydrogenated styrene-isoprene copolymer (Kuraray Co., Ltd. trade name "Septon 2007"; hereinafter abbreviated as "S2007") and radical generator P14. A modified resin-3 was obtained in the same manner except that the amount used of was changed from 6 g to 15 g.

Example 4 In Example 3, the amount of HEMA used was changed from 150 g to 300
Modified resin-4 was obtained in the same manner except that the amount was changed to g. Example 5 Modified resin-5 was obtained in the same manner as in Example 1 except that SM was not added.

Example 6 Maleic anhydride modified hydrogenated styrene-butadiene block copolymer (trade name "Tuftec M1913" manufactured by Asahi Kasei;
Hereinafter, abbreviated as "M1913") was used. Table 1 shows HEMA constitutional unit content and hydroxyl group residual ratio of these modified resins.

[0041]

[Table 1]

Examples 1 to 6, Comparative Examples 1 to 4 Polybutylene butarate (trade name "Novadol 5010" manufactured by Mitsubishi Kasei; hereinafter abbreviated as "PBT"), modified resins of Examples 1 to 6 and unmodified elastomer G1652. , S2007
Using a Labo Plastomill kneading machine (manufactured by Toyo Seiki Seisakusho Co., Ltd.) at the composition ratio shown in Table 2, the reaction temperature was 250 ° C and the rotation speed was
After kneading at 80 rpm for 5 minutes, it was pulverized to obtain a granular resin composition.

An injection molding machine (Custom Scientific (Custom Scientific)
(c) CS183MMX Mini Mac) manufactured by injection molding at a temperature of 260 ° C. was used to measure and evaluate the test pieces by the following methods. Table 2 shows the results. Before kneading and molding, it was dried at 120 ° C. for 5 hours in advance. (1) Izod impact strength: length 31.5 mm, width 6.
A test piece of 2 mm in thickness and 3.2 mm in thickness was injection-molded, and a notch tip R at 23 ° C. was 0.25 mm and a depth was 1 using an Izod impact tester (Minimax CS183TI type manufactured by Custom Scientific Co., Ltd.). The Izod impact strength with a notch of 0.2 mm was measured.

(2) Flexural modulus: length 45 mm, width 5 m
m, thickness 2 mm test piece is injection molded, solid viscoelasticity measuring device (Rheometrics Far East RSAII)
, Storage elastic modulus (E ') under the condition of frequency 1 Hz
Was measured to determine the bending elastic modulus at 23 ° C. (3) Appearance of molded product (layered peeling): Cellophane tape (product name "Jim Pack No. 1" manufactured by Nitto Denko Corporation) was sufficiently pressure-bonded to the surface of the test sample molded in (1) above, The area of the peeled portion was found by the gravimetric method, and the area of the peeled portion was expressed as a delamination rate in percentage as a percentage.

[0045]

[Equation 2]

As another characteristic, MFR (JI
SK-7210).

[0047]

[Table 2]

[0048]

The resin composition of the present invention has good fluidity,
Gives a molded product with a balanced notched Izod impact strength and flexural modulus.

Claims (1)

[Claims] 1. (A) Saturated polyester resin 50-99
%, And (B) 100 parts by weight of the hydrogenated product of the block copolymer of an aromatic vinyl compound and a conjugated diene compound, in the presence of a radical generator, a hydroxyl group-containing α, β-unsaturated carboxylic acid ester of 0.1. A thermoplastic resin composition containing 50 to 1% by weight of a modified resin obtained by melt-kneading 01 to 50 parts by weight and 0.01 to 50 parts by weight of an aromatic vinyl compound.