JP3293898B2 - Resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic resin comprising a specific maleimide copolymer, an aromatic polyester resin, a polyamide resin and a specific modified polyolefin, which has excellent mechanical properties, moldability and appearance of a molded article. It relates to a resin composition.

[0002]

2. Description of the Related Art Aromatic polyester resins have excellent properties such as mechanical properties, chemical resistance, abrasion resistance and electrical properties, but have the disadvantage of low impact resistance (notched). I have.

For the purpose of remedying this drawback, an aromatic polyester resin is an ABS (acrylonitrile-butadiene-styrene) resin, a resin obtained by modifying the same with an epoxy or the like, or an epoxy compound or the like as a third component. (JP-A-54-57563, JP-A-60-262847,
Nos. 61-130366, JP-A-1-123854 and JP-A-1-163249) are known, and polyolefins or those obtained by modifying the same with epoxy or the like, or further adding an epoxy compound or the like as a third component. (JP-B-57-54058, JP-A-59-184253, JP-A-61-204258, JP-A-63-128059,
JP-A-1-40555 and JP-A-1-204960), acrylic rubber, or those further containing an epoxy compound as a third component (JP-A-60-219256, JP-B-63-45746) Gazette) is known.

Although these resin compositions are sufficiently improved in impact resistance, it is necessary to add a large amount of an additive in order to enhance the effect of impact resistance. However, there are drawbacks that the temperature of the molded article is extremely reduced and the appearance of the molded article is impaired.

[0005] Further, the polyamide resin, like the aromatic polyester resin, has a drawback of low impact resistance (notched). However, although it is relatively easy to improve the impact resistance of a polyamide resin, the polyamide resin has high water absorption and a sharp decrease in rigidity.

[0006]

SUMMARY OF THE INVENTION The present invention is intended to improve the disadvantages of such aromatic polyester resins and polyamide resins, and it is intended that the present invention has excellent impact resistance and a good balance of other physical properties. Another object of the present invention is to provide a thermoplastic resin composition which gives a molded article a beautiful appearance.

[0007]

SUMMARY OF THE INVENTION In summary, the present invention relates to a thermoplastic resin composition comprising (A) 30 to 70 mol% of an aromatic vinyl monomer residue, maleimide Maleimide copolymer consisting of 25 to 50 mol% of monomer residue, 1 to 30 mol% of unsaturated dicarboxylic anhydride monomer residue and 0 to 44 mol% of other copolymerizable monomer residue 1 to less than 10% by weight of polymer, (B) aromatic polyester resin
20-80% by weight, (C) 10-50% by weight of polyamide resin,
(D) 3 to 40% by weight of a modified polyolefin polymer modified with 0.1 to 10% by weight of an unsaturated dicarboxylic acid anhydride monomer residue or an unsaturated carboxylic acid monomer residue. Characteristic thermoplastic resin composition.

The present inventors have found that the thermoplastic resin composition according to the present invention has excellent impact resistance, a good balance of other physical properties, excellent molding workability, and the molded article gives a beautiful appearance. It was found that.

The method for producing the maleimide copolymer used in the present invention is not particularly limited. For example, an aromatic vinyl monomer, a maleimide monomer, an unsaturated dicarboxylic anhydride monomer and Accordingly, it could be produced by radical copolymerization of other copolymerizable monomers.

Specific examples of the aromatic vinyl monomer include styrene, α-methylstyrene, vinyltoluene and t-
Butylstyrene and the like.

Specific examples of maleimide monomers include maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-hexylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide and N-tolylmaleimide. And the like.

Specific examples of the unsaturated dicarboxylic anhydride monomer include maleic anhydride, methylmaleic anhydride, 1,2-dimethylmaleic anhydride, ethylmaleic anhydride and phenylmaleic anhydride.

Specific examples of other copolymerizable monomers include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, and decyl ( There were meth) acrylate, octadecyl (meth) acrylate, hydroxyethyl (meth) acrylate, methoxyethyl (meth) acrylate and glycidyl (meth) acrylate, and these could be used alone or in combination. However, the term “methyl (meth) acrylate” as used herein means methyl acrylate or methyl methacrylate.

[0014] The copolymerization method using these monomers is not particularly limited, and any known radical copolymerization method can be used.

Other methods for producing the maleimide copolymer used in the present invention include aromatic vinyl monomers,
After copolymerizing the unsaturated dicarboxylic anhydride monomer and other copolymerizable monomers as necessary to obtain a copolymer, the copolymer is reacted with ammonia or a primary amine to form an acid anhydride group. Can be exemplified.

An imidization reaction between a polymer having an acid anhydride group in a polymer chain and an amine compound is known, and is disclosed, for example, in Japanese Patent Publication Nos. 61-26936 and 62-8456. According to the method described above, a polymer substance and an amine compound are reacted with each other to produce a maleimide-based copolymer having an intended imide group.

The primary amine used in the imidization reaction includes, for example, methylamine, ethylamine, propylamine, butylamine, hexylamine, cyclohexylamine, decylamine, aniline, toluidine, naphthylamine, chlorophenylamine, dichlorophenylamine, bromophenyl Amine and dibromophenylamine.

The imidization reaction can be carried out in a solution state, a bulk molten state or a suspension state using an autoclave. In addition, the imidization reaction can be performed in a molten state using a melt kneading device such as a screw extruder.

Solvents used in the solution reaction include, for example, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and siloxane hexanoan; ethers such as tetrahydrofuran and 1,4-dioxane; aromatic hydrocarbons such as toluene and xylene; Examples include dimethylformamide, dimethylsulfoxide and N-methyl-2-pyrrolidone.

The reaction temperature for imidization is preferably in the range of 50 to 350 ° C, particularly preferably in the range of 100 to 300 ° C. The imidization reaction does not necessarily require the presence of a catalyst, but if a catalyst is used, tertiary amines such as trimethylamine, triethylamine, tributylamine, N, N-dimethylaniline and N, N-diethylaniline are preferred. .

The maleimide copolymer used in the present invention comprises 30 to 70 mol% of an aromatic vinyl monomer residue, 25 to 50 mol% of a maleimide monomer residue, and an unsaturated dicarboxylic anhydride monomer. It consists of 1 to 30 mol% of body residues and 0 to 44 mol% of other copolymerizable monomer residues.

When the amount of the aromatic vinyl monomer residue is less than 30 mol%, it is difficult to industrially produce a copolymer having a homogeneous composition with good reproducibility. The resin composition obtained by mixing with another resin is inferior in properties such as thermal stability, moldability and mechanical strength. Further, if the aromatic vinyl monomer residue exceeds 70 mol% or the maleimide monomer residue is less than 25 mol%,
When the heat resistance of the obtained resin composition is inferior, and when the amount of the maleimide monomer residue exceeds 50 mol%, the moldability of the obtained resin composition is inferior.

When the unsaturated dicarboxylic anhydride monomer residue group is 1
When the amount is less than mol%, the compatibility between the aromatic polyester resin and the polyamide resin is poor, and the impact strength of the obtained resin composition is poor. On the other hand, when the amount of the unsaturated dicarboxylic anhydride monomer residue exceeds 30 mol%, the reaction with the hydroxyl group of the aromatic polyester resin or the amino group of the polyamide resin becomes excessive, and the fluidity is reduced.

The aromatic polyester resin used in the present invention is a polymer or copolymer obtained by a condensation reaction containing an aromatic dicarboxylic acid or a derivative thereof and an aliphatic glycol or a derivative thereof as main components.

Examples of the aromatic polyester resin include aromatic rings such as polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, polypentamethylene terephthalate, polyhexamethylene terephthalate, and polydecamethylene terephthalate. And these can be used alone or in combination.

The polyamide resin used in the present invention is not particularly limited, and may be a polyamide obtained from an aliphatic, aromatic or alicyclic dicarboxylic acid and a diamine, a polyamide obtained from an aminocarboxylic acid or a cyclic lactam. Good.

The polyamide resin is, for example, 6-nylon, 6,6-nylon, 6,9-nylon.
Nylon, 6,10-nylon, 6,12-nylon, 4,
Aliphatic polyamides such as 6-nylon, 11-nylon and 12-nylon and aromatic rings such as poly (hexamethylene terephthalamide), poly (hexamethylene isophthalamide) and poly (m-xylylene adipamide); And the like, and these can be used alone or in combination.

The modified polyolefin polymer used in the present invention refers to a polymer of an olefin monomer or a modified product of a copolymer thereof, and specific examples of the olefin monomer used include ethylene, propylene, and propylene. -Butene, isobutylene, 2-butene, cyclobutene, 3-methyl-1-butene, 4-methyl-1-butene, 4-methyl-1-pentene, cyclopentene, 1-hexene, cyclohexene, 1-octene, 1-decene And 1-dodecene.

The modified polyolefin-based polymer may have, for example, 20 to 90 mol% of ethylene, 10 to 80 mol% of α-olefin monomer and 0 to 10 mol% of other monomers, if a preferred composition range is exemplified. And the ethylene content in the polymer is
Particularly preferred is 50 to 85 mol%. Further, the glass transition temperature of these modified polyolefin-based polymers is -10 degrees Celsius or less, particularly preferably -30 degrees Celsius or less.

The modified polyolefin polymer is modified with an unsaturated dicarboxylic acid anhydride monomer residue or an unsaturated carboxylic acid monomer residue.

Specific examples of the unsaturated dicarboxylic anhydride monomer residues include maleic anhydride, methylmaleic anhydride, 1,2-dimethylmaleic anhydride, ethylmaleic anhydride and phenylmaleic anhydride. And maleic anhydride are particularly preferred. Further, specific examples of the unsaturated carboxylic acid monomer residue include acrylic acid and methacrylic acid.

The modified polyolefin polymer of the present invention comprises
Unsaturated dicarboxylic anhydride monomer residue or unsaturated carboxylic acid monomer residue, which is modified with 0.1 to 10% by weight, and when the modified amount is less than 0.1% by weight, the resin composition is If the impact strength is poor, and if it exceeds 10% by weight, the impact strength and the fluidity of the resin composition are reduced.

The term "modified" as used in the present invention means that a monomer residue used for the modification, for example, a maleic anhydride group, is present in the main chain or side chain of the polyolefin polymer. Modification can be performed by known techniques such as random copolymerization and graft polymerization. The denaturation method is not particularly limited. For example, JP-B-39-6810, JP-B-52-43677,
The denaturation can be carried out according to the methods disclosed in JP-A-53-5716, JP-A-56-9925 and JP-A-58-445.

The modified polyolefin-based polymer used in the present invention is preferably modified as a graft rather than introduced into the main chain, from the viewpoint of low-temperature impact resistance and the like. Further, it is preferable that the residual amount of unreacted monomer is as small as 0.5% by weight or less.

The molecular weight of the modified polyolefin polymer is as follows:
From the balance of impact resistance and moldability, 50,000 to 500,000, particularly preferably 100,000 to 300,000 is preferable. Examples of these modified polyolefin-based polymers include those commercially available under the trade name TUFMER MP-0620 by Mitsui Petrochemical Industries, Ltd.

The resin composition of the present invention comprises a maleimide copolymer in an amount of from 1 to less than 10% by weight and an aromatic polyester resin in an amount of from 20 to 80 %.
It is a composition obtained by mixing 10% to 50% by weight of a polyamide resin and 3 to 40% by weight of a modified polyolefin-based polymer.

When the amount of the maleimide-based copolymer is less than 1% by weight, the compatibility between the aromatic polyester resin and the polyamide resin is poor, and the impact strength of the obtained resin composition is low. When the amount of the maleimide-based copolymer is 10% by weight or more, the impact strength and the fluidity of the obtained resin composition decrease.

When the content of the aromatic polyester resin exceeds 80% by weight, or when the content of the polyamide resin is less than 10% by weight, the impact strength of the obtained resin composition is low. When the amount of the aromatic polyester resin is less than 20% by weight or the amount of the polyamide resin exceeds 50% by weight, the water absorption is high and the rigidity is drastically reduced.

When the content of the modified polyolefin polymer is less than 3% by weight, the effect of improving the impact strength is low, and when it exceeds 40% by weight, the rigidity is greatly reduced.

The mixing of the maleimide-based copolymer, aromatic polyester resin, polyamide resin and modified polyolefin-based polymer of the present invention can be carried out using a conventional melt-kneading apparatus. Examples thereof include a screw-type kneading extruder, a Banbury mixer, a kneader, and a mixing roll.

Further, the resin composition of the present invention can be made into a resin composition by adding other additives or modifiers depending on the application. Specifically, glass resin, carbon fiber and Examples include reinforcing fibers such as aramid fibers, fillers such as talc, silica, clay, mica, and calcium carbonate, other light stabilizers, ultraviolet absorbers, antioxidants, flame retardants, lubricants, and coloring agents.

[0042]

The present invention will be described in more detail with reference to the following examples. These are all examples and do not limit the content of the present invention. In addition, the measuring method of various properties is as follows.

Method for measuring physical properties Impact strength: Notched with a 1/8 ″ thick injection molded product according to ASTM D-256, left for 24 hours under absolute drying conditions
IZOD specimens were measured at a temperature of 23 ° C. Rigidity: According to ASTM D-790, a flexural modulus was measured on a test piece left for 24 hours under absolute drying conditions using an injection molded product having a thickness of 1/4 ". Water absorption physical property: Injection with a thickness of 1/4" After immersing the molded article in water for 10 days, the flexural modulus was measured according to ASTM D790, and the water absorption at that time was measured.

Melt flow rate (MFR): ASTM D-1
Based on 238, the outflow amount was measured at 265 ° C. under a load of 10 kg for 10 minutes. Appearance: A molded article having a boss and ribs on the back surface and having an opening was molded with a 5 oz injection molding machine, and the appearance was visually judged. ：: The entire surface of the molded product is smooth. Δ: Part of the molded product surface is rough. ×: The entire surface of the molded product is rough. In addition, the injection molding temperature in the above test piece preparation was about 250 ° C.
Met. The polymers used for measuring the physical properties are as follows.

(1) Maleimide copolymer (A) 100 parts by weight of styrene was charged into an autoclave equipped with a stirrer, and the inside of the system was replaced with nitrogen gas. Heated. To this, a solution prepared by dissolving 67 parts by weight of maleic anhydride and 0.2 part by weight of benzoyl peroxide in 300 parts by weight of methyl ethyl ketone was added over 8 hours. After the addition, the temperature was kept at 80 ° C. for a further 4 hours.
To the above copolymer, 1.2 parts by weight of triethylamine and 44 parts by weight of aniline were added and reacted at 130 ° C. for 7 hours.
The reaction solution was cooled to room temperature and vigorously stirred methanol.
The mixture was poured into 300 parts by weight, filtered and dried to obtain a maleimide copolymer (a-2). Various maleimide-based copolymers were also synthesized by the same operation under different conditions to obtain the copolymers shown in Table 1.

[0046]

[Table 1]

The symbols in the table are as follows. ST: Styrene VT: Vinyl toluene PMI: N-phenylmaleimide TMI: Toluylmaleimide MAH: Maleic anhydride MMA: Methyl methacrylate

(2) Aromatic polyester resin (B) The aromatic polyester resin has a number average molecular weight of 40,000 obtained from terephthalic acid and 1,4-butylene glycol.
A polybutylene terephthalate resin (b-1) having a carboxyl group of 20% of all terminals was used.

(3) Polyamide resin (C) As the polyamide resin, 6-nylon (c-1) having a relative viscosity of concentrated sulfuric acid of 2.35 obtained from ε-caprolactam was used.

(4) Modified polyolefin-based copolymer (D) The modified polyolefin-based polymer has a polymerization ratio of ethylene / propylene copolymer / maleic anhydride of 100/0 (d-
1), 99.5 / 0.5 (d-2), 99.1 / 0.9 (d-3) and 9
A polymer having a ratio of 8.0 / 2.0 (d-4) was used. For example, d
-3 is 8.0 kg of ethylene / propylene copolymer pellets having an ethylene content of 80 mol%, and 96 g of powdered maleic anhydride.
8.0 g of 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 was charged into a 20-liter Henschel mixer through which nitrogen was passed, and the mixture was stirred for 5 minutes to uniformly blend. 240 ° C polymer temperature
Extruder (flowing nitrogen, L
/ T-28, dalmage type) to obtain a pellet-shaped graft reaction product.

Example 1 0.2 kg of a maleimide-based copolymer (A) and 2.12 kg of an aromatic polyester resin (B) so that the proportions shown in Table 2 were obtained.
And 0.92 kg of polyamide resin (C) and 0.76 kg of modified polyolefin-based copolymer (D) were charged into a 20-liter Henschel, blended, and then subjected to a TEM35B extruder (manufactured by Toshiba Corporation, two axes in the same direction) to obtain a temperature of 260 Extruded and pelletized at ℃. Using the pellets, test specimens for measuring physical properties were prepared by an injection molding machine, and various physical properties and the like were measured. Table 2 shows the physical property measurement results.
Shown in

Examples 2 to 12 and Comparative Examples 1 to 13 Using the formulations shown in Tables 2 and 3, test pieces for measuring physical properties were prepared in the same manner as in Example 1, and various physical properties were measured. The measurement results are shown in Tables 2 and 3.

[0053]

[Table 2]

[0054]

[Table 3]

In Comparative Examples 1 and 2, the content of the maleimide copolymer was out of the range of the present invention. In Comparative Examples 3 and 4, the content of the aromatic polyester resin and the content of the polyamide resin are outside the scope of the present invention. In Comparative Examples 5 and 6, the content of the modified polyolefin-based copolymer is out of the range of the present invention. In Comparative Example 7, the contents of the maleimide-based copolymer and the polyamide resin were out of the range of the present invention.

In Comparative Example 8, the contents of the maleimide-based copolymer, the aromatic polyester resin and the polyamide resin were outside the scope of the present invention. In Comparative Example 9, the content of the polyamide resin is out of the range of the present invention. In Comparative Example 10, the content of the aromatic polyester resin is out of the range of the present invention. Comparative example
In Nos. 11 and 12, the maleimide anhydride content of the maleimide copolymer is out of the range of the present invention. In Comparative Example 13, the content of maleic anhydride in the modified polyolefin-based copolymer was out of the range of the present invention.

The following is clear from the results of the above examples and comparative examples. From Example 1 and Comparative Example 1, it can be seen that the impact strength was low without the maleimide-based copolymer. Also, as in Comparative Example 2, even if the amount of the maleimide-based copolymer is too large, the impact strength becomes low. Example 1 and Comparative Example 3
From this, it is understood that when the amount of the aromatic polyester resin is too small and the amount of the polyamide resin is too large, the water absorption is high and the rigidity is drastically reduced.

When the amount of the aromatic polyester resin is too large and the amount of the polyamide resin is too small as in Comparative Example 4, the impact strength becomes low. From Example 1 and Comparative Example 5, it can be seen that the impact strength was low without the modified polyolefin copolymer. Also, as in Comparative Example 6, when the amount of the modified polyolefin-based copolymer is too large, the rigidity is low. From Example 1 and Comparative Example 11, it can be seen that if the amount of the unsaturated dicarboxylic anhydride monomer group in the maleimide-based copolymer is too small, the impact strength becomes low.

When the amount of the unsaturated dicarboxylic anhydride monomer residue in the maleimide-based copolymer is too large as in Comparative Example 12, the fluidity is reduced and the appearance of the molded article is also deteriorated. From Example 1 and Comparative Example 13, the absence of the unsaturated dicarboxylic anhydride monomer residue or unsaturated carboxylic acid monomer residue in the modified polyolefin-based copolymer results in poor impact strength of the molded article. It can be seen that the appearance also deteriorated.

As described above, the maleimide-based copolymer is
The unsaturated dicarboxylic acid anhydride monomer residue, the modified polyolefin-based copolymer contains an unsaturated dicarboxylic acid anhydride monomer residue or an unsaturated carboxylic acid monomer residue, respectively, in an appropriate amount, and It can be seen that only when the aromatic polyester resin and the polyamide resin are contained in an appropriate ratio, the balance of physical properties becomes good.

[0061]

Industrial Applicability The resin composition of the present invention is excellent in impact resistance, has a good balance of other physical properties, has good moldability, and has a beautiful appearance of a molded product obtained, and is suitable for various industrial parts. There is an advantage that the practical value of the material is extremely high.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 67/00-67/03 C08L 77/00-77/12

Claims (1)

(57) [Claims] (A) 30 to 70 mol% of an aromatic vinyl monomer residue, 25 to 50 mol% of a maleimide monomer residue, 1 to 30 mol of an unsaturated dicarboxylic anhydride monomer residue % And less than 1 to 10% by weight of a maleimide copolymer comprising 0 to 44 % by mole of other copolymerizable monomer residues, (B) 20 to 80% by weight of an aromatic polyester resin, and (C) a polyamide resin 3 to 40% by weight of a modified polyolefin polymer modified with 10 to 50% by weight and (D) 0.1 to 10% by weight of an unsaturated dicarboxylic acid anhydride monomer residue or an unsaturated carboxylic acid monomer residue. A thermoplastic resin composition characterized by comprising: