JPH0791426B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention comprises a crystalline polyolefin, a polycarbonate, a styrene-ethylene / butylene-styrene block copolymer and a low crystalline ethylene / α-olefin copolymer, and is excellent. The present invention relates to a thermoplastic resin composition having excellent impact resistance, moldability and chemical resistance.

[Conventional technology and problems]

A composition comprising a composite of a polyolefin and a polycarbonate is known in order to improve the mechanical strength of the polyolefin and the moldability and solvent resistance of the polycarbonate. However, since the compatibility between polyolefin and polycarbonate is not so good, it has been proposed to add various third components in order to improve the compatibility.

JP-A-57-108151 discloses a polycarbonate resin composition prepared by mixing 100 parts by weight of a polycarbonate resin with 0.3 to 20 parts by weight of polyethylene and 0.3 to 20 parts by weight of butyl rubber. Further, JP-A-57-108152 discloses a polycarbonate resin composition containing 0.3 to 20 parts by weight of an ethylene / propylene copolymer and / or an ethylene / propylene / diene copolymer as a third component. Further, JP-A-57-111351 discloses a polycarbonate resin composition containing 0.3 to 20 parts by weight of isoprene rubber and / or methylpentene polymer as a third component.
However, in all of these polycarbonate resin compositions, when the amount of polyethylene exceeds 10%, the impact strength sharply decreases and the surface peeling of the molded product is also observed.

In addition to the above polycarbonate resin composition, various polycarbonate compositions containing a different third component have been proposed. For example, JP-A-56-76449 and JP-A-59-133.
No. 247 discloses a thermoplastic resin composition obtained by blending a polycarbonate and a polyolefin with an ABS resin. However, the ABS resin is insufficient in the effect of improving the compatibility, and particularly when the content of the polyolefin is 10% or more, the mechanical strength of the thermoplastic resin composition decreases.

In addition, in JP-A-59-196360, a copolymer of at least one olefin and an acrylate, methacrylate, acrylic acid or methacrylic acid monomer, for example, an ethylene / ethyl acrylate copolymer (EEA resin) is blended as a third component. The disclosed polycarbonate resin composition is disclosed. Further, JP-A-61-215649 discloses a polycarbonate resin composition prepared by blending an olefin / vinyl ester copolymer such as ethylene / vinyl acetate copolymer (EVA resin) as a third component. Furthermore, JP-A-61-11
No. 5945 discloses a composition containing styrene-ethylene / butylene-styrene block copolymer (SEBS resin) as a third component. However, EEA resin, E
When either VA resin or SEBS resin is blended, the compatibility is slightly improved, or there is a problem that surface peeling is insufficient. Moreover, the impact strength is not sufficient.

Therefore, the object of the present invention is to improve the compatibility of the crystalline polyolefin and the polycarbonate, suppress the surface peeling phenomenon,
And to provide a thermoplastic resin composition having improved impact strength.

[Means for solving problems]

As a result of earnest research in view of the above problems, the present inventor has found that a composition of a polyolefin, a polycarbonate and a styrene-ethylene / butylene-styrene block copolymer has a low crystalline ethylene / α-olefin copolymer as a fourth component. It was discovered that the addition of these compounds improves impact resistance, surface peeling resistance, etc. while maintaining excellent moldability, chemical resistance, etc., and conceived the present invention.

That is, the thermoplastic resin composition of the present invention comprises 95 to 5% by weight of crystalline polyolefin, 5 to 95% by weight of polycarbonate, and 5 to 100 parts by weight of styrene in total of 100 parts by weight of crystalline polyolefin and polycarbonate. Ethylene / butylene-styrene block copolymer and low crystalline ethylene / α-olefin copolymer (the weight ratio of both is 30
/ 70 to 95/5).

Examples of the crystalline polyolefin include polyethylene, polypropylene and other α-olefin polymers, preferably polypropylene. The crystalline polyolefin does not have to be a homopolymer and may be a copolymer with another α-olefin. For example, in the case of polypropylene, it may contain up to 20% by weight of other α-olefins such as ethylene. The copolymer may be a random copolymer, a block copolymer or a graft copolymer. The weight average molecular weight of the crystalline polyolefin is 10,000 to 1,000,000, preferably 30,000 to 300,000. The melt flow rate (MFR) measured at 230 ° C. is 500 to 0.01 g / 10 minutes, preferably 50 to 1 g / 10 minutes.

The crystallinity of the crystalline polyolefin is 20% or more when measured by the X-ray diffraction method. When the crystallinity is less than 20%, the resulting thermoplastic resin composition has low mechanical strength. The preferred crystallinity is 40% or more.

The polycarbonate used in the present invention is (a) a reaction between a dihydric phenol and a carbonate precursor such as phosgene in the presence of an acid acceptor and a molecular weight modifier, or (b) a dihydric phenol and a carbonate precursor such as diphenyl carbonate. It can be produced by a transesterification reaction with. The dihydric phenol that can be used here is preferably bisphenols, and particularly preferably 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).
Further, a part or all of bisphenol A may be replaced with another dihydric phenol. Examples of the dihydric phenol other than bisphenol A include hydroquinone, 4,4'-hydroxydiphenyl, and bis (4-hydroxyphenyl).
Alkane, bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ketone, bis ( 4-hydroxyphenyl)
Mention may be made of ethers and the like and halogenated bisphenols such as bis (3,5-dibromo-4-hydroxyphenyl) propane. It may be a homopolymer of these dihydric phenols, a copolymer using two or more thereof, or a mixture thereof. Such a polycarbonate resin can be easily obtained as a commercial product.

The weight average molecular weight of the polycarbonate is preferably 10,000 to 100,000, and if it is less than 10,000, the mechanical properties are insufficient, and if it exceeds 100,000, molding becomes difficult. A more preferable weight average molecular weight is 20,000 to 50,000.

The styrene-ethylene-butylene-styrene block copolymer is a block copolymer in which a styrene portion and an ethylene / butylene portion are in a block shape, and the weight ratio of styrene / ethylene / butylene is 10/90 to 70/30. Is.
If it is less than 10/90, the strength is insufficient, and if it exceeds 70/30, it becomes brittle. The preferred styrene / ethylene / butylene weight ratio is 20/80 to 50/50. Also styrene-
The weight average molecular weight of the ethylene / butylene-styrene block copolymer is 10,000 to 1,000,000, and if it is less than 10,000, the mechanical strength is insufficient, and if it exceeds 1,000,000, the dispersion in the composition deteriorates. Become. The styrene portion is not limited to styrene alone, and may be substituted styrene such as methylstyrene.

The styrene-ethylene / butylene-styrene block copolymer can be produced by the method described in U.S. Pat. Nos. 3,595,942 and 4,188,432. That is, only a butadiene portion is selected by hydrogenating a styrene-butadiene / styrene block copolymer at a temperature of 25 to 175 ° C in the presence of a catalyst obtained by reducing an alkoxide of cobalt or nickel with an alkylaluminum compound. Is hydrogenated to a structure corresponding to a copolymer of ethylene and butene-1. In the present invention, styrene-
The ethylene / butylene-styrene block copolymer is not limited to the above method, and any one produced by any method can be used.

The low crystalline ethylene / α-olefin copolymer is a copolymer of ethylene and α-olefin such as propylene, butylene and pentene, and ethylene / propylene rubber and ethylene / butylene rubber are particularly preferable. Ethylene and α-
The weight ratio with the olefin is 20:80 to 85:15. Weight ratio
If it is less than 20:80 or more than 85:15, the rubber elasticity decreases.
The preferred weight ratio of ethylene / α-olefin is 30:70 to 7
It is 0:30. The α-olefin is not limited to one type, but 2
It may contain more than one kind.

The weight average molecular weight of the low crystalline ethylene / α-olefin copolymer is 30,000 to 1,000,000. If it is less than 30,000, the composition has insufficient strength, and if it exceeds 1,000,000, the dispersion becomes poor.
A preferred weight average molecular weight is 50,000 to 200,000. The crystallinity of the low crystalline ethylene / α-olefin copolymer is 20% or more when measured by an X-ray diffraction method, and preferably 0 to
10%. Furthermore, the melting flow rate (MFR) of low crystalline ethylene / α-olefin copolymer is 0.01 to 50 g / m at 230 ° C.
It is 10 minutes, preferably 0.1 to 20 g / 10 minutes.

In the present invention, the ratio of crystalline polyolefin to polycarbonate is 95-5% by weight to 5-95% by weight. If the polycarbonate is less than 5% by weight, sufficient impact resistance and mechanical strength cannot be obtained, and if it exceeds 95% by weight, moldability and solvent resistance are deteriorated. Preferably from 10 to 10% by weight of crystalline polyolefin and 10 to 10% of polycarbonate.
90 wt%, more preferably 20 to 80 wt% polycarbonate to 80 to 20 wt% crystalline polyolefin
Is.

The total amount of styrene-ethylene / butylene-styrene block copolymer and low crystalline ethylene / α-olefin copolymer is crystalline polyolefin + polycarbonate 100.
It is 5 to 100 parts by weight with respect to parts by weight. The total amount is 5
If the amount is less than 100 parts by weight, the resulting thermoplastic resin composition has insufficient impact resistance, surface peeling resistance, and strength. If the amount is more than 100 parts by weight, the rigidity is greatly reduced and it cannot be put to practical use. The preferred total amount is 10 to 50 parts by weight, more preferably 20 to 40 parts by weight.

The weight ratio of the styrene-ethylene / butylene-styrene block copolymer to the low crystalline ethylene / α-olefin copolymer is 30:70 to 95: 5. If the weight ratio is less than 30:70, the compatibility is insufficient, and if it exceeds 95: 5, the surface peeling resistance and the impact strength are deteriorated. The preferred weight ratio is 50:50 to 90:10.

The thermoplastic resin composition of the present invention further has other additives for the purpose of modification, for example, reinforcing materials such as glass fibers and carbon fibers, inorganic fillers, heat stabilizers, antioxidants,
A light stabilizer, a flame retardant, a plasticizer, an antistatic agent, a release agent, a foaming agent, etc. can be added. Further, if necessary, an acrylic elastomer, butyl rubber or the like may be contained as a rubber component in an amount of about 1 to 20% by weight of the whole.

The thermoplastic resin composition of the present invention is a single screw extruder, a twin screw extruder, a Banbury mixer, a kneading roll, a Brabender,
A kneader such as a kneader or a mixer such as a Henschel mixer is used to obtain the mixture by kneading in a heated and molten state.

〔Example〕

 The invention will be explained in more detail by the following examples.

In addition, in each Example and Comparative Example, the measurement of the physical property value was performed as follows.

(1) Flexural modulus = measured by ASTM D 790.

(2) Measured by ASTM D 256 at Izod impact strength = 23 ° C and -30 ° C, respectively.

(3) Tensile breaking elongation = measured by ASTM D638.

(4) Dynamic melt viscosity (η100 rad / sec) = 250 with a dynamic spectrometer manufactured by Rheometrics
Measured at 100 ℃ / sec at ℃.

(5) Surface peeling resistance = 1 m with a razor on the surface of the molded product
100 squares of mx 1 mm were attached, cellophane tape (Nichiban) was attached to the squares, and then stripped off. Of the 100 squares, the number remaining on the surface of the molded product without adhering to the cellophane tape was counted.

(6) Weight change due to immersion in methanol = Molded article was immersed in methanol at 25 ° C for 30 days, and the change in weight was measured.

Examples 1 to 7 Crystalline polypropylene pellets (MFR = 9.0 g / 10 min), polycarbonate resin (Panlite L122 manufactured by Teijin Chemicals Ltd.)
5), styrene-ethylene / butylene-styrene block copolymer (Shell Chemical Co., Ltd., Kraton G1650, styrene / rubber weight ratio = 28/72), and ethylene / propylene rubber (Mitsui Petrochemical Co., Ltd. Tuffmer P) 0180) First
The composition shown in the table was mixed with a Henschel mixer at room temperature, and then kneaded at 250 ° C. using a biaxial kneader to obtain a composition pellet.

For each thermoplastic resin composition obtained, flexural modulus,
The Izod impact strength, tensile elongation at break, dynamic melt viscosity, resistance to surface peeling and solvent resistance (weight change by immersion in methanol) were measured. The results are also shown in Table 1.

Example 8 A thermoplastic resin composition was prepared in the same manner as in Example 3 except that 10 parts by weight of an ethylene / butene-1 copolymer (Tufmer A 4085 manufactured by Mitsui Petrochemical Co., Ltd.) was added instead of the ethylene / propylene rubber. It was prepared and the physical properties were measured. The results are shown in Table 1.

Example 9 A propylene block copolymer (Tonen Petrochemical Co., Ltd. BJ 309;
Propylene 92.7% by weight, ethylene content 7.3% by weight, MFR
= 9 g / 10 min), a thermoplastic resin composition was prepared in the same manner, and the physical properties were measured. The results are shown in Table 1.

Example 10 A thermoplastic resin composition was prepared in the same manner as in Example 3 except that Clayton G1657 (styrene / rubber weight ratio = 14/86, Shell Chemical Co., Ltd.) was used as the styrene-ethylene / butylene-styrene block copolymer. The product was prepared and the physical properties were measured. The results are shown in Table 1.

Comparative Examples 1 and 2 A thermoplastic resin composition was prepared in the same manner as in Example 1 except that the two-component system of crystalline polypropylene and polycarbonate was used, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 3 Crystalline polypropylene pellets (MFR = 9.0g / 10min), polycarbonate resin (manufactured by Teijin Chemicals Ltd., Panlite L1)
225) and ethylene / propylene rubber (Timer P 0180 manufactured by Mitsui Petrochemical Co., Ltd.) with the composition shown in Table 2 in a Henschel mixer at room temperature and then using a twin-screw kneader.
Kneading was performed at 250 ° C. to obtain a composition pellet.

The physical properties of the obtained thermoplastic resin compositions were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 4 A thermoplastic resin composition was prepared in the same manner as in Comparative Example 3 except that a styrene-ethylene / butylene-styrene block copolymer (Clayton G1650 manufactured by Shell Chemical Co., Ltd.) was added instead of the ethylene / propylene rubber. The physical properties were measured. The results are shown in Table 2.

Comparative Example 5 Instead of the ethylene / propylene rubber in Example 3, an ethylene-vinyl acetate copolymer (NU manufactured by Nippon Unica Co., Ltd.) was used.
C DQ DJ 3269) was added and a thermoplastic resin composition was prepared in the same manner, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 6 A thermoplastic resin composition was prepared in the same manner as in Example 3 except that an ethylene-ethyl acrylate copolymer (NUC 6570 manufactured by Nippon Unica Co., Ltd.) was added instead of the ethylene / propylene rubber, and the physical properties were measured. did. The results are shown in Table 2.

Comparative Example 7 Physical properties were similarly measured in the case of 100% by weight of polycarbonate. The results are shown in Table 2.

Comparative Example 8 The same thermoplasticity was used except that the total amount of styrene-ethylene / butylene-styrene block copolymer and ethylene / propylene rubber was increased to 60 parts by weight (150 parts by weight per 100 parts by weight of polypropylene + polycarbonate). A resin composition was prepared and the physical properties were measured. The results are shown in Table 2.

As is clear from the results of Tables 1 and 2, the thermoplastic resin composition of the present invention has excellent flexural modulus, impact resistance, and ductility as compared with the thermoplastic resin composition outside the scope of the present invention. , Moldability (represented by dynamic melt viscosity), surface peel resistance and solvent resistance.

〔The invention's effect〕

As described above in detail, since the thermoplastic resin composition of the present invention contains the styrene-ethylene / butylene-styrene block copolymer and the ethylene / α-olefin copolymer, the phase of the polyolefin and the polycarbonate is It has improved solubility and has good mechanical strength, impact resistance and surface peel resistance. Moreover, the moldability and chemical resistance, which are the drawbacks of polycarbonate, are also improved. The thermoplastic resin composition of the present invention can be used as an engineering plastic material, particularly for automobiles and household electric appliances.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kichiyoshi Kitano 1-2-4 -225 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Prefecture (72) Inventor Kiyotada Narukawa 1256 Shitomi, Tokorozawa, Saitama 14 (72) Inventor Takashi Nomi 3-2348 Izumihonmachi, Komae City, Tokyo (72) Inventor Takao Nomura 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Toshio Yokoi Toyota City, Aichi Prefecture Toyota Town No. 1 Toyota Motor Co., Ltd. (72) Inventor Takesumi Nishio Toyota Town, Aichi Prefecture Toyota Town No. 1 Toyota Motor Co., Ltd. (56) Reference JP-A-64-75546 (JP, A)

Claims (7)

[Claims] 1. A crystalline polyolefin, (b) a polycarbonate, (c) a styrene-ethylene / butylene-styrene block copolymer, and (d) a low crystalline ethylene / α-olefin copolymer. The content of (a) is 95 to 5% by weight and the content of (b) is 5
% To 95% by weight, (c) + (d) is 5 to 100 parts by weight, and (c) / (d) is weighted to 100 parts by weight of (a) + (b). A thermoplastic resin composition having a ratio of 30/70 to 95/5. 2. The thermoplastic resin composition according to claim 1, wherein the crystalline polyolefin is polypropylene. 3. The thermoplastic resin composition according to claim 1 or 2, wherein the crystalline polyolefin is 90 to 10% by weight, and the polycarbonate is 10 to 10% by weight.
90% by weight of a thermoplastic resin composition. 4. The thermoplastic resin composition according to claim 1, wherein the styrene block in the styrene-ethylene / butylene-styrene block copolymer is 10 to 70% by weight. %, And the ethylene / butylene block is 90 to 30% by weight, the thermoplastic resin composition. 5. The thermoplastic resin composition according to any one of claims 1 to 4, wherein the low crystalline ethylene / α-olefin copolymer is ethylene / propylene rubber or ethylene / butylene rubber. And a thermoplastic resin composition. 6. The thermoplastic resin composition according to any one of claims 1 to 5, wherein (a) +
(C) + (d) with respect to 100 parts by weight of (b)
Is 10 to 50 parts by weight, the thermoplastic resin composition. 7. The thermoplastic resin composition according to any one of claims 1 to 6, wherein (c) /
The thermoplastic resin composition, wherein the weight ratio of (d) is 50/50 to 90/10.