JPH0543767A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide a thermoplastic resin composition having characteristics of polyolefins in combination with that of polyesters and excellent in mechanical properties, surface properties and environmental properties. CONSTITUTION:A thermoplastic resin composition characterized by its composition containing (a) a polyester, (b) a polyolefin containing >=2wt.% modified polyolefin and (c) a phenoxy resin in a weight ratio of (a)/(b)=(2/98)-(98-2) while satisfying that the content of the component (c) is 2-40 pts.wt. based on 100 pts.wt. total amount of (a) and (b).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic resin composition containing a polyester and a polyolefin. More specifically, polyester and polyolefin are well compatible with each other and have excellent mechanical properties such as impact resistance and mechanical strength, and excellent surface properties such as water resistance, heat resistance, insulation, and appearance. The present invention relates to a thermoplastic resin composition suitable for use in molded articles such as electric appliances, electric parts, and home electric appliances.

[0002]

2. Description of the Related Art Polyester has heat resistance,
It is a resin with excellent mechanical strength and insulation. Compared with this, polyolefin has the features of being lightweight and excellent in impact resistance, and having good environmental characteristics such as moldability and water resistance. Therefore, attempts have been made to prepare a resin composition having the advantages of both by blending polyester and polyolefin, each of which has excellent characteristics. However, since the compatibility of polyester and polyolefin is poor, there is a problem that impact resistance and mechanical strength of the thermoplastic resin composition containing both are lowered. Therefore, by blending a thermoplastic resin composition containing a polyester and a polyolefin with an unsaturated carboxylic acid or a derivative thereof, particularly a polyolefin modified with an anhydride of an unsaturated dicarboxylic acid such as maleic anhydride (MAH), Although it has been attempted to improve the compatibility and dispersibility of polyester and polyolefin to improve impact resistance and water resistance, this method still fails to improve the physical properties by compatibilization. Therefore, an object of the present invention is to provide a thermoplastic resin composition in which polyester and polyolefin are well compatibilized with each other and which have excellent mechanical properties, surface properties and environmental properties.

[0003]

Means for Solving the Problems As a result of intensive studies made by the present inventors, when polyester and polyolefin are blended with a specific amount of a modified polyolefin and a phenoxy resin, the polyester and polyolefin are well compatibilized. The present invention has been accomplished by finding that a thermoplastic resin composition having excellent mechanical properties, surface properties and environmental properties can be obtained. That is, the present invention contains (a) a polyester, (b) a polyolefin containing 2% by weight or more of a modified polyolefin, and (c) a phenoxy resin,
The weight ratio of the components (a) and (b) is (a).
/ (B) = 2/98 to 98/2, and the content of the component (c) is 2 to 100 parts by weight of the total of (a) + (b).
The thermoplastic resin composition is 40 parts by weight.

Hereinafter, the thermoplastic resin composition of the present invention will be described in detail. (A) of the thermoplastic resin composition component of the present invention
Polyester is a thermoplastic resin generally obtained by polycondensation of a saturated dicarboxylic acid and a saturated dihydric alcohol,
Examples thereof include polyethylene terephthalate, polypropylene terephthalate, polytetramethylene terephthalate (polybutylene terephthalate), polyhexamethylene terephthalate, polycyclohexane-1,4-dimethylol terephthalate, and polyneopentyl terephthalate. Of these, polyethylene terephthalate and polybutylene terephthalate are preferred.

The polyester as the above component (a) is
The intrinsic viscosity [η] (dl / g) obtained from the solution viscosity measured at 25 ° C in an o-chlorophenol solvent is 0.30 to 1.
It is preferable that the terminal carboxyl group has a terminal carboxyl group concentration of 10 to 200 meq / kg. In the case of polyethylene terephthalate, it is preferable that the intrinsic viscosity [η] is 0.30 to 1.2 and the terminal carboxyl group concentration is 10 to 200 meq / kg.
The terephthalic acid component in polyethylene terephthalate may be substituted with an alkyl group, a halogen group or the like, and the glycol component may be up to about 50% by weight of another glycol such as 1,4-, in addition to ethylene glycol.
It may contain butylene glycol, propylene glycol, hexamethylene glycol and the like. In the case of polybutylene terephthalate, the intrinsic viscosity [η] is 0.30
Preferably, the terminal carboxyl group concentration is 10 to 200 meq / kg. Also in this case, the terephthalic acid component may be substituted with an alkyl group, a halogen group or the like, and the glycol component may be 1,4-butylene glycol or another glycol such as ethylene glycol or propylene glycol up to about 50% by weight. Hexamethylene glycol and the like may be contained.

The thermoplastic resin composition component (b) of the present invention
With polyolefin, ethylene and propylene, butene-1, hexene-1,3-methylbutene-1,4-
Methyl-pentene-1, heptene-1, octene-1,
Homopolymers of α-olefins having 3 or more carbon atoms such as decene-1, copolymers of two or more types of monomers such as random, block and graft, mixtures thereof, ethylene or α-olefins having 3 or more carbon atoms Random, block, graft, etc. copolymers of the main part of the above with other unsaturated monomers. Among these polyolefins, ethylene or propylene homopolymers, ethylene and propylene copolymers, and ethylene or propylene and other α-olefin copolymers are preferable. Especially preferred is
It is a copolymer of propylene and ethylene having an ethylene content of 20% by weight or less, and such a copolymer is usually 0.1
~ 200g / 10min melt flow rate (MF
R, JIS K7210, load 2.16 kg, 230 ° C). As a homopolymer of ethylene, high-pressure low-density polyethylene (LDPE) or low-pressure high-density polyethylene (HDPE)
However, linear low density polyethylene (LLDPE), which is known as a low-pressure ethylene copolymer, can be used.

It is also possible to use a mixture of the above-mentioned polypropylene and an olefin elastomer up to about 40% by weight. Here, the olefin elastomer means two or more copolymer rubbers of α-olefins such as ethylene, propylene, butene-1, hexene-1, and 4-methyl-pentene-1, or α-olefins. And a monomer of another kind. Above α
-Specific examples of the copolymer rubber of two or more kinds of olefins include ethylene-propylene copolymer rubber (EP
R), ethylene-butene copolymer rubber (EBR) and ethylene-propylene-diene copolymer rubber (EPD)
M) can be mentioned. Examples of the diene component in the ethylene-propylene-diene copolymer rubber (EPDM) include non-conjugated dienes such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene and methylnorbornene, or conjugated dienes such as butadiene and isoprene. Can be mentioned. A propylene random copolymer (PPDM) containing a non-conjugated diene comonomer represented by the following general formula (1) can also be used as the component (b).

[0008]

[Chemical 2]

[In the formula, R _{1 to} R ₄ are hydrogen atoms or alkyl groups having 1 to 6 carbon atoms, and n is an integer of 1 to 20. ]

Component (b) of the thermoplastic resin composition of the present invention
The modified polyolefin contained in an amount of 2% by weight or more is the above-mentioned various polyolefins modified with an unsaturated carboxylic acid or a derivative thereof. Here, the unsaturated carboxylic acid and its derivative used as the modifier are copolymerizable with an olefin, and specific examples thereof include acrylic acid, methacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, and itacone. Unsaturated mono- or dicarboxylic acids such as acid, citraconic acid, crotonic acid, isocrotonic acid, or derivatives thereof, such as acid, halide, amide, imide, anhydride, ester and the like can be mentioned. Specific examples of the derivative include maleny chloride, maleimide, maleic anhydride, methyl acrylate, methyl methacrylate, citraconic anhydride, monomethyl maleate, dimethyl maleate and the like. Of these, unsaturated dicarboxylic acids or their derivatives are preferable, and maleic acid or its anhydride is particularly preferable. The above unsaturated carboxylic acids and their derivatives can be used alone or in combination of two or more kinds.

Examples of the raw material polyolefin modified with the above-mentioned modifier include those exemplified as the above-mentioned component (b), and among these, polyethylene and polypropylene are particularly preferably used. As mentioned above, polypropylene includes PPDM in addition to ethylene as well as ethylene, but also copolymerized with other α-olefins such as butene and 4-methylpentene-1 up to about 40% by weight. LDPE, HDPE and LLD
PE is included.

The modified polyolefin preferred in the present invention is one obtained by modifying the above-mentioned raw material polyolefin, especially polyethylene or polypropylene, with the above unsaturated dicarboxylic acid or its anhydride, particularly maleic acid or maleic anhydride. The content of the unsaturated compound as the modifier of the modified polyolefin varies depending on the kind of the raw material polyolefin and cannot be generally specified, but is generally about 0.01 to 30% by weight, preferably 0.05 to 10% by weight.

Such modified polyolefin can be obtained by utilizing a known modification method such as a solution method or a melt kneading method. In addition, a commercially available product may be appropriately selected and used. As a specific example of the modification method, a modification example of the polypropylene with the maleic anhydride (MAH) (melt kneading method) is shown below. Polypropylene and maleic anhydride are put into an extruder, a twin-screw kneader, or the like, and heated to a temperature of about 170 to 300 ° C. to be melted, and kneaded for about 0.1 to 20 minutes to obtain a modified polypropylene. In the case of the solution method, the above starting materials are dissolved in an organic solvent such as xylene,
Denaturation is carried out at a temperature of about 90 to 200 ° C. for 0.1 to 100 hours with stirring.

In any modification method, a conventional radical polymerization catalyst can be used as a catalyst, for example, benzoyl peroxide, lauroyl peroxide, ditertiary butyl peroxide, acetyl peroxide, tert-butyl peroxybenzoic acid. Acids, peroxides such as dicumyl peroxide, peroxybenzoic acid, peroxyacetic acid, tertiary butyl peroxypivalate, 2,5-dimethyl-2,5-ditertiary butyl peroxyhexyne, and azobisisobutyronitrile Diazo compounds and the like are used. The amount of the catalyst added is about 0.1 to 10 parts by weight with respect to 100 parts by weight of maleic anhydride for modification. It is also possible to add a phenolic antioxidant during the above graft reaction. Further, modification with another unsaturated compound such as maleic acid can also be carried out according to the above-mentioned method.

The modified polypropylene thus obtained has a graft ratio of about 0.1 to 10% by weight, and a graft ratio of 1 to 1000 g /
Melt flow rate of about 10 minutes (MFR, JISK7210,
It has a load of 2.16 kg and 230 ° C.) and is preferably used in the present invention. Further, modification of other raw material polyolefin such as polyethylene can be carried out according to the above-mentioned method, and the graft ratio of maleic acid or maleic anhydride is 0.1 to 10
Modified polyethylene having a melt flow rate (MFR, JIS K7210, load of 2.16 kg, 230 ° C.) of about 0.05 to 1000 g / 10 minutes in weight% is also preferable.

In the present invention, in order to improve the compatibilization of the above components (a) and (b), the phenoxy resin (c) is used.
Blend. (C) of the thermoplastic resin composition component of the present invention
The phenoxy resin is generally a polycondensate of bisphenol A and epichlorohydrin, and is specifically a polymer represented by the following general formula (2).

[0017]

[Chemical 3]

The above phenoxy resin has a weight average molecular weight (M
w) of 1,000 to 200,000 is preferable, especially 10,000
Those of -60,000 are preferred. Such a phenoxy resin can be produced, for example, by reacting bisphenol A and epichlorohydrin in a solution at 20 to 100 ° C. for 1 to 30 hours. Further, commercially available products having the above-mentioned molecular weight range may be appropriately selected and used.

The mixing ratio of the above components (a), (b), and (c) is such that the unmodified polyolefin and the modified polyolefin in the component (b) are in a weight ratio of 98/2 to 0.
/ 100, preferably 95/5 to 0/100. The present invention also includes compositions in which the total amount of component (b) is a modified polyolefin. That is, the composition comprising the polyester of the component (a), the modified polyolefin of the component (b), and the phenoxy resin of the component (c) is excellent in compatibility and has the characteristics of both the polyester and the polyolefin and is included in the present invention. It is what is done. However, the weight ratio of the unmodified polyolefin to the modified polyolefin in the component (b) is 98.
If it is less than / 2, the amount of the modified polyolefin is too small, and the effect of improving the compatibility between the polyester and the polyolefin due to its blending is not recognized.

The weight ratio of the component (a) (polyester) to the component (b) (that is, (a) / (b)).
2/98 to 98/2, preferably 5/95 to 95/5
Is. If the weight ratio is less than 2/98, the amount of polyester is too small, and if it exceeds 98/2, the amount of modified polyolefin is small and the effect of improving compatibility is not recognized.

Further, the component (c) (phenoxy resin)
Is the total amount of component (a) and component (b) (ie,
2 to 40 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight of (a) + (b)). If the amount is less than 2 parts by weight, the effect of improving the compatibility between the polyester and the polyolefin by using the phenoxy resin is not recognized, and if the amount is more than 40 parts by weight, the mechanical properties of the composition are adversely affected.

In the thermoplastic resin composition of the present invention, for the purpose of further strengthening and modifying it, fillers and reinforcing materials such as glass fibers, heat stabilizers, light stabilizers, flame retardants, plasticizers, antistatic agents. , A foaming agent, a nucleating agent and the like can be added.
The thermoplastic resin composition of the present invention is a uniaxial extruder, a biaxial extruder, a Banbury mixer, a kneading roll, each of the above components.
It can be obtained by heating and melting and kneading at 230 to 320 ° C., preferably 250 to 280 ° C. using a kneader such as Brabender. In the present invention, the kneading order of each component is not particularly limited, and the components (a), (b) and (c) may be kneaded together, or after kneading the components (a) and (b), The component (c) may be kneaded. Furthermore, the unmodified polyolefin and the modified polyolefin may be independently used as the component (b), the unmodified polyolefin and the component (a) may be kneaded, and then the modified polyolefin and the component (c) may be kneaded. The kneading order of can also be taken. In any kneading, when kneading the component (a), the component (b) and the component (c),
Acids such as p-toluenesulfonic acid and sulfuric acid can be used as the catalyst. Preferable acid is p-toluenesulfonic acid, and the addition amount of the catalyst is (a) +
0.01 to 5 per 100 parts by weight of the total amount of (b) + (c)
It is about part by weight.

[0023]

The thermoplastic resin composition of the present invention comprises a polyester, a polyolefin, and a modified polyolefin and a phenoxy resin, and the polyester and the polyolefin, which are resin components, are well compatibilized with each other. It is a thermoplastic resin composition which is excellent in impact resistance, heat resistance, mechanical strength, insulation, and water resistance, and which does not peel off from the surface.
The reason why the thermoplastic resin composition of the present invention exerts such effects is not always clear, but the polyester and the polyolefin are mediated by the interaction between the modified polyolefin and the phenoxy resin and the interaction between the phenoxy resin and the polyester. It is thought that this is due to compatibilization.

[0024]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. In each of the examples and comparative examples, the following materials were used as raw materials and additives. Polyester (1) Polyethylene terephthalate PET: [TR 4550BH manufactured by Teijin Limited, intrinsic viscosity [η]
0.70 (in o-chlorophenol)] (2) Polybutylene terephthalate PBT: [C-7000N manufactured by Teijin Ltd., intrinsic viscosity [η]
1.07 (in o-chlorophenol)] Polyolefin (1) Polypropylene homopolymer PP: [J209 manufactured by Tonen Kagaku KK, melt flow rate (MFR, 230 ° C, 2.16 kg load) 8.5 g / 10 minutes,
Weight average molecular weight (Mw) 200,000] (2) Polyethylene homopolymer HDPE: [J6140V manufactured by Tonen Chemical Co., Ltd., melt flow rate (MFR, 190 ° C, 2.16 kg load) 5.0 g / 1
0 minutes] Modification monomer MAH (maleic anhydride) radical generator POX: Perhexin 25B [manufactured by NOF Corporation] Phenoxy resin commercial product: [YP50 manufactured by Toto Kasei Co., Ltd., weight average molecular weight (Mw) 58,600]

Modified Polyolefin (1) Synthesis Example 1 of Modified Polyolefin Polypropylene homopolymer [Y20 manufactured by Tonen Kagaku Co., Ltd.
1. Melt flow rate (MFR, 230 ° C., 2.16 kg load) 1.0 g / 10 min] 100 parts by weight, 1 part by weight of MAH and 0.1 part by weight of POX were dry-blended, and then this was mixed with a uniaxial extruder having a diameter of 65 mm. Using, 200 ℃, 150
Melt kneading under the conditions of rpm, melt flow rate (MF
R, 230 ° C., 2.16 kg load) 150 g / 10 min of modified polypropylene (PO-1) was obtained. The MAH graft ratio of this modified polypropylene was 0.25% by weight. The graft ratio was calculated by the following method. In the IR spectrum of the modified polypropylene (measured by dissolving the modified polypropylene in boiling xylene, removing the insoluble matter, precipitating the dissolved components with methanol, and pressing this to a thickness of about 50 μm), MAH Peak related to stretching and contraction of carbonyl (C = O) bond (1780c
The ratio of m ^-1 ) to one of the peaks (840 cm ^-1 ) peculiar to isotactic polypropylene was determined and used as the graft ratio. (2) Synthesis example 2 of modified polyolefin Polyethylene homopolymer [HDPE, J6311 manufactured by Tonen Chemical Co., Ltd., melt flow rate (MFR, 190 ° C,
2.16 kg load) 1.0 g / 10 minutes] 100 parts by weight, MAH
After dry blending 1 part by weight and 0.1 part by weight of POX, this was mixed with a single screw extruder having a diameter of 65 mm to 200
Melt-kneading was carried out under the conditions of .degree. C. and 150 rpm to obtain a modified polyethylene (PO-2) having a melt flow rate (MFR, 190.degree. C., 2.16 kg load) of 0.1 g / 10 min. The MAH graft ratio of this modified polyethylene was 0.8% by weight.

Examples 1 to 22, Comparative Examples 1 to 12 Polyester (PET or PBT), polyolefin (PP or HDPE), modified polyolefin (P
O-1 or PO-2) and the phenoxy resin were dry-blended in a ratio shown in Table 1 by a Henschel mixer, and then, a twin screw extruder (L / D = 30) having a diameter of 45 mm was used at 250 ° C. and 200 rpm. The mixture was kneaded to obtain pellets of the resin composition. The thermoplastic resin composition thus obtained is injection-molded to obtain a melt flow rate (MF) of a molded product.
R, 250 ° C, 2.16kg load), surface peelability, 23 ° C
The flexural modulus, the Izod impact strength, the elongation at break and the yield strength, and the heat distortion temperature were measured. First result
Shown according to the table.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

[Table 4]

The methods for measuring the physical properties shown in Table 1 above are as follows. (1) Melt flow rate: Measured according to JIS K7210. (2) Surface releasability: 100 squares of 1 mm × 1 mm were attached to the surface of the test piece using a razor, cellophane tape (manufactured by Nichiban Co., Ltd.) was attached to the squares, and then peeled off. Among 100 squares, the number of squares remaining on the surface of the test piece without adhering to the cellophane tape was counted. (3) Flexural modulus (23 ° C.): measured by ASTM D-790. (4) Izod impact strength (23 ° C): measured by ASTM D-256. (5) Elongation at break (23 ° C): measured by ASTM D-638. (6) Yield point strength (23 ° C): measured by ASTM D-638. (7) Heat distortion temperature (load 4.6 kg / cm ² ): Measured by ASTM D-648.

As is apparent from Table 1, a composition comprising polyester and unmodified polyolefin (Comparative Example 5)
~ 7, 11 and 12) are polyesters (Comparative Example 1,
2) and polyolefins (Comparative Examples 3 and 4),
It is found that the surface releasability, the flexural modulus, the Izod impact strength, the elongation at break, the yield strength and the heat deformation temperature are all inferior, and the compatibility between polyester and polyolefin is poor. Also, a composition obtained by blending a modified polyolefin with a polyester and an unmodified polyolefin (Comparative Examples 8 to 10).
Although the surface releasability is slightly improved, other physical properties are still insufficient. On the other hand, the thermoplastic resin composition of the present invention is a composition comprising the polyester lacking the phenoxy resin and an unmodified polyolefin (Comparative Examples 5 to 7, 11 and 12), and the polyester and the unmodified polyolefin. Compared with the composition comprising a modified polyolefin (Comparative Examples 8 to 10), surface peelability, flexural modulus, Izod impact strength, elongation at break,
Yield strength and heat distortion temperature are all good.

[0033]

As described in detail above, the thermoplastic resin composition of the present invention comprises a polyolefin and a polyester, and a modified polyolefin and a phenoxy resin which improve the compatibility of the two, and It excels in impact resistance, heat resistance, mechanical strength, insulation, and water resistance, and has good surface properties such as surface peeling resistance. Such a thermoplastic resin composition of the present invention is suitable as various engineering plastics, particularly as a resin composition for interior and exterior parts of automobiles, home electric appliance parts, industrial material parts, packaging materials and the like.

Front page continued (72) Inventor Katsuyuki Yokomizo 1-3-1 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Prefecture Tonen Corporation Research Institute (72) Yuji Fujita 1-3-3 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Prefecture No. 1 Tonen Co., Ltd. Research Institute

Claims (3)

[Claims] 1. A (a) polyester, and (b) a polyolefin containing 2% by weight or more of a modified polyolefin,
(C) a phenoxy resin, and the ratio of the components (a) and (b) is (a) / (b) = 2/98 in weight ratio.
Is about 98/2, and the content of the component (c) is (a) +
2 to 40 parts by weight based on 100 parts by weight of the total of (b), a thermoplastic resin composition. 2. The component (b) is a polyolefin modified with an unsaturated carboxylic acid or a derivative thereof.
The thermoplastic resin composition according to. 3. The component (c) has the following general formula: The thermoplastic resin composition according to claim 1 or 2, which is a phenoxy resin having a weight average molecular weight of 1,000 to 200,000.