JP2912634B2 - Maleimide-based thermoplastic resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a resin composition excellent in impact resistance, heat resistance and moldability.

[Problems to be improved by conventional technology and invention]

Maleimide copolymers are excellent in heat resistance and thermal decomposition resistance, but have poor mechanical properties and moldability represented by impact strength, and many proposals have been made to improve these disadvantages. I have. For example, a method of polymerizing a maleimide and another vinyl monomer in the presence of a rubbery polymer (Japanese Patent Laid-Open No. 59-11322), or grafting a maleimide-based copolymer with a rubbery and vinyl-based monomer A method of mixing with a polymer (Japanese Patent Application Laid-Open No. 61-73755) is disclosed. However, in these methods, if the heat resistance is to be improved, mechanical properties such as impact resistance are reduced. There is a problem that if the impact resistance is improved, the heat resistance will decrease.Therefore, it is difficult to obtain a material having both heat resistance and impact resistance.If both performances are to be satisfied, only a material with poor moldability is required. The fact is that it cannot be obtained.

[Means and actions for solving the problems]

In view of these circumstances, the present inventors, without reducing the excellent heat resistance of the maleimide copolymer, mechanical strength represented by impact strength, as a result of intensive research to improve moldability, Maleimide-based polymer component (A) essentially including copolymer (1) having a specific functional group-hereinafter, in this specification, may be simply referred to as component (A)-and react with the functional group A maleimide-based thermoplastic resin comprising a flexible polymer component (B) essentially including a flexible polymer (2) having a functional group capable of being treated-hereinafter simply referred to as component (B) in the present specification. The inventors have found that the composition can achieve the above object, and have completed the present invention.

That is, in the maleimide-based thermoplastic resin composition according to the present invention, the resin contains 95 to 50% by weight of the maleimide-based polymer component (A) and 5 to 50% by weight of the soft polymer component (B) (provided that
The total of the components (A) and (B) is 100% by weight), and the maleimide-based polymer component (A) is a monomer (a) having an oxazoline group in a molecule of 0.5 to 2%.
Indispensable is a copolymer (1) of 0% by weight and 80 to 99.5% by weight of a monomer (b) having no functional group capable of reacting with an oxazoline group, and 500 parts per 100 parts by weight of the copolymer (1). The polymer (3) having a functional group compatible with the copolymer (1) and having no functional group capable of reacting with the oxazoline group may be contained in an amount of not more than part by weight. A maleimide-based polymer component in which the incorporated maleimide unit accounts for 5 to 70% by weight of the entire component, and the soft polymer component (B) has a functional group capable of reacting with an oxazoline group; The skeleton portion is composed of at least one soft polymer (2) selected from a gen-based polymer, an olefin-based polymer, and an acrylic rubber, and is 500 parts by weight or less based on 100 parts by weight of the soft polymer (2). Within the range, is compatible with the soft polymer (2) and reacts with the oxazoline group. A soft polymer component, which may contain a polymer (4) having no functional group that can be used.

In the present invention, a compatibilizer is generated by a chemical interaction between the polymer (1) and the soft polymer (2), and the component (A) and the component (B), which are essentially incompatible, are in a microphase separated state. Is formed, the heat resistance of the component (A) and the component (B)
Thus, a thermoplastic resin composition having both impact resistance and easy moldability can be obtained.

In the present invention, as the polymer (1), one selected from an aziridine group, an oxazoline group, and an epoxy group in the molecule.
Any polymer can be used without particular limitation as long as it has a kind or a polymer having two or more kinds of functional groups. To obtain such a polymer (1),
For example, a polymerizable monomer (a) having the functional group in the molecule
A method of polymerizing (hereinafter, referred to as a monomer (a)) with another polymerizable monomer (b) (hereinafter, referred to as a monomer (b)) copolymerizable therewith, if necessary. be able to.

Examples of the monomer (a) include 2-vinyl-2-oxazoline and 2-vinyl-4-4-
Methyl-2-oxazoline, 2-vinyl-5-methyl-
2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-4,5-dimethyl- Examples thereof include oxazoline group-containing polymerizable monomers such as 2-oxazoline, and one or more selected from these groups can be used.

The amount of the monomer (a) having these functional groups is preferably 0.1 to 50% by weight in the polymer (1), more preferably
Preferably, it is 0.5 to 20% by weight.

As the monomer (b), a monomer having no functional group capable of reacting with the functional group contained in the monomer (a) and copolymerizable with the monomer (a) is used. It can be used without particular limitation, for example, maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-isobutylmaleimide, N-tert-butylmaleimide, N-cyclohexylmaleimide , N-phenylmaleimide, N
Maleimide monomers such as -chlorophenylmaleimide, N-methylphenylmaleimide, N-naphthylmaleimide, N-laurylmaleimide, N-methoxyphenylmaleimide, N-nitrophenylmaleimide, N-tribromophenylmaleimide; styrene, o -Methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-methoxystyrene, p-tert-butylstyrene, p-phenylstyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene Styrene monomers such as methyl acrylate, ethyl acrylate,
N-butyl acrylate, isobutyl acrylate, dodecyl acrylate, stearyl acrylate, 2-acrylate
Acrylic or methacrylic acid such as ethylhexyl, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate Monomer, vinyl chloride, vinyl acetate, acrylonitrile, acrylamide, methacrylamide,
N-vinylpyrroline and the like can be mentioned, and one or more of these can be used.

In order to obtain the polymer (1) having a functional group by this method, the monomer (a) is optionally added together with the monomer (b) to a conventionally known polymerization method such as a bulk polymerization method, a suspension polymerization method, and an emulsion method. The polymerization may be performed by a polymerization method, a solution polymerization method, or the like. When the component (A) is composed of only the polymer (1), the above-mentioned maleimide monomer must be essentially contained as the monomer (b).

In the present invention, the polymer (1) is used as the component (A) by adding the polymer (3) as necessary. The polymer (3) is not particularly limited as long as it is a polymer that is compatible with the polymer (1) and does not have a functional group capable of reacting with a functional group in the copolymer (1). A polymer obtained by polymerizing the monomer (b) is particularly preferred from the viewpoint of compatibility. The amount of the polymer (3) is not particularly limited, but is preferably 500 parts by weight or less based on 100 parts by weight of the polymer (1). In the present invention, the component (A) must contain 5 to 70% by weight of maleimide units. If it is less than 5% by weight, the heat resistance is insufficient, and if it exceeds 70% by weight, there is a problem in moldability, which is not preferable.

The soft polymer (2) used in the present invention has a functional group capable of reacting with an aziridine group, an oxazoline group, or an epoxy group. Examples of the functional group include a carboxyl group and a salt thereof, a carboxylic anhydride group, Examples thereof include a hydroxyl group, a mercapto group, and an amino group, and these may be used in combination.

Further, the skeleton portion of the polymer (2) is soft and has good impact resistance, for example, gen-based polymers such as polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer; polyethylene, chlorinated polyethylene Olefin polymers such as ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene copolymer and ethylene-vinyl acetate polymer; and acrylic rubbers such as polybutyl acrylate and poly-2-ethylhexyl acrylate. It is composed of at least one selected polymer.

A preferred method for obtaining the flexible polymer (2) is a method of graft-copolymerizing an unsaturated carboxylic acid or an unsaturated carboxylic anhydride to the flexible polymer in an amount of 0.1 to 50% by weight, more preferably 0.3 to 20% by weight. Or a method of copolymerizing as one component of a soft polymer.

In the present invention, the flexible polymer (2) is used as the component (B) by adding the flexible polymer (4) as necessary. The soft polymer (4) is not particularly limited as long as it is a polymer that is compatible with the soft polymer (2) and has no functional group. A polymer having a similar skeleton is particularly preferred from the viewpoint of compatibility. The use amount of the soft polymer (4) is not particularly limited,
The range is preferably 500 parts by weight or less based on 100 parts by weight of the flexible polymer (2).

In the present invention, the amount of the component (A) in the resin composition is 95 to 50% by weight. If it exceeds 95% by weight, impact resistance and moldability deteriorate, and if it is less than 50% by weight, heat resistance becomes insufficient, which is not preferable.

The resin composition according to the present invention may contain, if necessary, a conventionally known additive such as an antioxidant, a weather resistance improver, an impact resistance improver, an inorganic or organic filler as long as the object of the present invention is not impaired. It is also possible to add a flame retardant, a coloring agent, an antistatic agent, a release agent and the like. As a blending method for obtaining the resin composition according to the present invention, a conventionally known method such as a Henschel mixer, a ribbon blender, a V blender and the like, followed by a single-screw kneading extruder, a twin-screw kneading extruder, a Banbury A method of melt-kneading with a mixer, a roll kneader or the like can be used. From the resin composition thus obtained, a desired molded product can be further produced by extrusion molding, injection molding, or the like.

〔The invention's effect〕

The resin composition according to the present invention has excellent mechanical properties and moldability while maintaining the heat resistance and thermal decomposition resistance inherently provided by the maleimide-based polymer. Therefore, the resin composition according to the present invention can be effectively used for various uses such as automobile parts, industrial parts, electric equipment parts and the like.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited thereto. In the examples, “parts” are by weight unless otherwise specified.

REFERENCE EXAMPLE 1 Deionized water was added to a 2-liter glass four-necked flask equipped with a stirrer.
1260 parts and polyvinyl alcohol (PVA-220E, manufactured by Kuraray Co., Ltd.) 0.56 part were charged, heated to 80 ° C. in a nitrogen gas atmosphere to dissolve the polyvinyl alcohol, and then cooled to 50 ° C.

351 parts of styrene, 162 parts of N-phenylmaleimide, and 27 parts of 2-isopropenyl-2-oxazoline (manufactured by Dow Chemical Company) were weighed in a separate container and heated to 40 ° C. to dissolve the N-phenylmaleimide. Later, benzoyl peroxide 16.2
Was added to obtain a uniform monomer solution. This monomer solution was added to the flask, and under a nitrogen gas atmosphere, kept under stirring at 300 rpm for 10 minutes to bring the monomer solution into a suspended state, and then the internal temperature was raised to 80 ° C. The polymerization was started and thereafter kept at this temperature for 7 hours to complete the polymerization. The obtained reaction solution is
After filtering through a 200 mesh wire mesh, washing thoroughly with deionized water, and drying all day and night with a hot air circulating drier at 80 ° C, the diameter is approx.
About 500 parts of a 0.2 mm granular copolymer (1a) were obtained.

Reference Example 2 In Reference Example 1, the monomer composition in the monomer solution was 513 parts of styrene and 2-isopropenyl-2-oxazoline 2
The same operation as in Reference Example 1 was repeated except that the amount was changed to 7 parts, to obtain about 500 parts of a granular copolymer (1b) having a diameter of about 0.2 mm.

Reference Example 3 The same operation as in Reference Example 1 was repeated except that the monomer composition in the monomer solution was changed to 378 parts of styrene and 162 parts of N-phenylmaleimide, to thereby obtain a granular copolymer having a diameter of about 0.2 mm. (3a) About 500 parts were obtained.

Reference Example 4 In Reference Example 1, the same operation as in Reference Example 1 was repeated except that the monomer composition in the monomer solution was changed to only 540 parts of styrene, to obtain about 500 parts of the granular polymer (3d) having a diameter of about 0.2 mm. Obtained.

Reference Example 5 Deionized water was added to the glass four-necked flask with stirrer of 1.
169.7 parts and 26.7 parts of a 15% Emar 0 aqueous solution were charged and heated to 55 ° C. in a nitrogen gas atmosphere (reaction tank).

162.6 parts of butyl acrylate, 12.6 parts of methyl methacrylate, 12.6 parts of styrene, acrylic acid
7.2 parts and 5 parts of trimethylolpropane trimethacrylate were charged and stirred to obtain a uniform monomer solution.

The reaction vessel was maintained at 55 ° C., and 40 parts of a 2.5% aqueous potassium persulfate solution and 2 parts of a 2% aqueous sodium bisulfite solution were added. The mixture was maintained under a nitrogen gas atmosphere with stirring for 10 minutes to obtain a uniform solution. Next, the monomer solution was dropped from the dropping tank over 90 minutes. During this time, 2% at 10 minute intervals after the start of dropping
Two parts of an aqueous solution of sodium bisulfite were added 9 times. Thereafter, the temperature was maintained at this temperature for 3 hours to complete the polymerization. The resulting reaction solution was dropped into a 4% aqueous solution of magnesium sulfate to carry out salting out, and the agglomerated polymer was sufficiently washed with deionized water, and then dried with a hot air circulating drier at 80 ° C. for one day to react. About 180 parts of a soft copolymer (2a) was obtained.

Examples 1 to 6 and Comparative Examples 1 to 5 The components were melt-kneaded using a biaxial kneader at the ratios shown in Table 1, and injection-molded to produce test specimens. At this time, the moldability other than Comparative Example 4 was good. Table 1 shows the performance test results of the obtained test pieces. The heat distortion temperature in the table is
ASTM D-648-56, Izod impact strength is ASTM D-256-56 Me
It was measured according to thod A.

As is clear from the table, the molded article obtained from the resin composition of the present invention was excellent in heat resistance and impact resistance.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobuaki Otsuki 5-8 Nishiburi-cho, Suita-shi, Osaka Inside the Central Research Laboratory of Nippon Shokubai Chemical Industry Co., Ltd. No. 5-8 Inside the Central Research Laboratory of Nippon Shokubai Chemical Co., Ltd. (56) References JP-A-63-86724 (JP, A) JP-A-63-161047 (JP, A) JP-A-63-137943 (JP, A A) JP-A-63-295624 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 35/00-35/06 C08L 57/04-57/12

Claims (1)

(57) [Claims] (1) The resin is a maleimide polymer component (A) 95
-50% by weight and 5-50% by weight of the soft polymer component (B) (however, the total of the components (A) and (B) is 100% by weight), and the maleimide polymer component (A) Monomer having an oxazoline group in the molecule (a) 0.5 to 20
Indispensable is a copolymer (1) of 80% to 99.5% by weight of a monomer (b) having no functional group capable of reacting with an oxazoline group, and 500 parts by weight per 100 parts by weight of the copolymer (1) In the range of not more than 3 parts by weight, the polymer (3) which is compatible with the copolymer (1) and has no functional group capable of reacting with the oxazoline group may be contained, and is incorporated into the component by an unsaturated double bond. A maleimide-based polymer component in which the obtained maleimide unit accounts for 5 to 70% by weight of the whole component, and the soft polymer component (B) has a functional group capable of reacting with an oxazoline group; The part consists of at least one soft polymer (2) selected from the group consisting of a gen-based polymer, an olefin-based polymer and an acrylic rubber, and 500 parts by weight or less based on 100 parts by weight of the soft polymer (2). Within the range, compatible with the soft polymer (2) and reacting with oxazoline groups A functional group which may have no polymer which may include (4), a soft polymer component, it maleimide-based thermoplastic resin composition characterized.