JPH02127456A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic resin composition, consisting essentially of a methacrylimide-containing polymer and thermoplastic polyurethane and excellent in heat, impact resistance and molding processability. CONSTITUTION:A thermoplastic resin composition obtained by blending (A) 1-99 pts.wt., preferably 5-95 pts.wt. methacrylimide-containing polymer with preferably <=1.2 mequiv. content of acid and acid anhydride groups containing >=10wt.% methacrylimide units expressed by the formula (R is H or 1-20C aliphatic, aromatic or alicyclic hydrocarbon group) with (B) 1-99 pts.wt., preferably 5-95 pts.wt. thermoplastic polyurethane.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a thermoplastic resin composition with excellent heat resistance, impact resistance, and moldability, which is mainly composed of a methacrylimide-containing polymer and a thermoplastic polyurethane. relating to things.

[Prior art] Although methacrylimide-containing polymers with excellent heat resistance have a high heat distortion temperature and are excellent in rigidity, surface hardness, and moldability, they have low mechanical strength, typified by impact strength. At present, the use of the containing polymer alone as a molding material is quite limited.

On the other hand, thermoplastic polyurethane is well known as a thermoplastic elastomer with excellent mechanical strength, abrasion resistance, and oil resistance, and is also known to have many excellent properties. However, such thermoplastic polyurethane is often used alone as a thermoplastic elastomer, and its uses are relatively limited.

(Problem to be Solved by the Invention J) The present inventors have studied the development of a resin that compensates for the drawbacks of these two resins, and found that by blending them in a specific ratio, a methacrylimide-containing polymer can be produced. The present inventors have discovered that, while maintaining the excellent properties of methacrylimide-containing polymers, the impact strength and moldability of methacrylimide-containing polymers in particular can be significantly improved.

[Means to solve the problem]

That is, the present invention comprises 1 to 99 parts by weight of a methacrylimide-containing polymer (A) containing at least 10% by weight of methacrylimide units represented by the following general formula (1) and 1 to 99 parts by weight of a thermoplastic polyurethane (B). This thermoplastic resin composition has excellent heat resistance, impact resistance, and moldability.

(In the formula, R represents a hydrogen atom or an aliphatic, aromatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms.) [Function] The methacrylimide-containing polymer (A) used in the present invention is
It is a polymer or copolymer containing a cyclic imide unit represented by the above general formula (1).

If it contains 10% by weight or more of the above cyclic imide unit,
Any methacrylimide-containing polymer having any chemical structure can be used. R is generally hydrogen, methyl, ethyl, propyl, butyl or phenyl.

The method for producing the methacrylimide-containing polymer is not particularly limited. For example, polymethyl methacrylate and ammonia or a primary amine such as methylamine or ethylamine are mixed in a suitable solvent (for example, an aromatic hydrocarbon such as benzene, toluene, xylene, or ethylbenzene, or an alcohol such as methanol, ethanol, or propatool alone or Using a mixed solvent of two or more selected from them,
Heat the reaction at 170 to 350°C in an autoclave,
A method of forming an imide ring is useful. Alternatively, the reaction may be carried out in an extruder as described in JP-A-52-63989.

The cyclic imide unit represented by the above general formula (1) must be contained in an amount of at least 10% by weight based on the polymer. Heat resistance cannot be demonstrated.

It is well known that when the above production method is used, imidization reaction intermediates such as methacrylic acid groups and acid anhydride groups are produced as by-products in the obtained polymer (example λ is disclosed in JP-A-62
-89705). In order to control the amount of this by-product, in addition to changing the reaction conditions (e.g. reaction temperature, etc.),
In addition to the use of polymethyl methacrylate, which is one of the raw materials, there is also a method of using a methyl methacrylate-methacrylic acid copolymer, and this method is a preferred method.

In order to obtain the resin composition of the present invention, it is preferable that the amount of acid groups and acid anhydride groups of the above-mentioned by-products present in the methacrylimide-containing polymer is 1.2 milliequivalent or less. 1
．． If it exceeds 2 milliequivalents, the water resistance of the resin composition tends to be impaired.

The thermoplastic polyurethane (B) used in the present invention preferably has properties as a thermoplastic elastomer. (proester type), (b) polytetramethylene glycol type) and (C) adipic acid type. The caprolactone type is obtained by addition polymerizing a polyisocyanate to a polylactone polyol obtained by ring-opening caprolactone in the presence of a short chain polyol. The polytetramethylene glycol type is obtained by addition polymerizing polyisocyanate to polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran in the presence of a short chain polyol. The adipic acid type is obtained by addition polymerizing a polyisocyanate to an adipic acid ester polyol of adipic acid and glycol in the presence of a short chain polyol.

Regardless of these types, thermoplastic polyurethane elastomers are composed of soft segments and hard segments, and are highly flexible, have excellent moldability, have excellent abrasion resistance, and have excellent mechanical strength and oil resistance. It is something.

In the present invention, these thermoplastic polyurethanes (B
) may be used in combination.

The thermoplastic resin composition of the present invention comprises 1 to 99 parts by weight of a methacrylimide-containing polymer (A) and a thermoplastic polyurethane (
B) 1 to 99 parts by weight.

However, the heat resistance of methacrylimide-containing polymers,
In order not to impair the mechanical properties of the thermoplastic polyurethane, it is preferable to use 5 to 95 parts by weight of the methacrylimide-containing polymer (A) and 5 to 95 parts by weight of the thermoplastic polyurethane.

The methacrylimide-containing polymer (A) and the thermoplastic polyurethane (B) can be blended by, for example, melting and mixing the granules, powders, or chips of each component in a V-type blender, super mixer, Ni-Goo, etc., forming them into chips, and then molding. This can be done by such methods as

A thermal decomposition inhibitor and an ultraviolet absorber may be added to the resin composition of the present invention in order to improve heat resistance, light resistance, and oxidative deterioration resistance. It can also be used as a plasticizer, pigment, or lubricant. Furthermore, it can be reinforced by adding fibrous materials such as glass fibers and carbon fibers.

The resin composition of the present invention further includes an acrylonitrile-butadiene-styrene terpolymer (ABS resin), a methyl methacrylate-butadiene-styrene terpolymer (
MBS resin), impact-resistant resins such as ethylene/propylene/diene terpolymer rubber (EPDM)-acrylonitrile lucid non-graft polymer (AES resin), ethylene ionomer resins, and glycidyl ester groups. Typical impact strength can be improved by blending rubber-like polymers with thermoplastic elastomers such as modified polyethylene, polyether Nisdel, polyether ester amide, and polyether amide as impact modifiers in an amount of up to about 40% by weight. It is possible to further improve the mechanical properties.

Further, other polymers may be mixed in a small amount (up to about 20% by weight) to adjust various properties of the resin composition to desired ones. For example, styrene-acrylonitrile copolymer (AS resin), styrene-methyl methacrylate-acrylonitrile copolymer, α-methylstyrene-styrene-
Examples of the other polymers include acrylonitrile copolymers and the like.

The composition of the present invention can be press-molded using powder chips or other shapes.1. Various useful molded products can be made using commonly known plastic molding methods such as injection molding, blow molding, and extrusion molding.

[Examples] Hereinafter, the present invention will be described in more detail based on Examples.

Note that parts and % in the examples mean parts by weight and % by weight. The heat distortion temperature was measured in accordance with ASTM 0648-56 (load: 18.56 kg/cm2), and the impact strength was measured in accordance with ASTM D 256-56 Method A. In addition, the melt index value of the composition (
Ml value) was measured according to ASTM D-1238 and was used as an index of moldability of the resin composition.

Amount of imidization (%) of methacrylimide-containing polymer (A)
The nitrogen content was determined using the measured elemental analysis value (measuring device CHN coder (MT-3) manufactured by Yanagimoto Seisakusho). Also proton NMRJN
M-FX-100 (JEOL) Schectrometer 1
Measured at 00MHz. The amount of imidization used herein is assumed to be a repeating structure of a methacrylimide ring structural unit and a methyl methacrylate unit represented by the following -shell structural formula, and the value of X is defined as the amount of imidization. In order to determine this X, N-
X was determined from the integral ratio of the methyl absorption of CH, and the methyl absorption of +0-CH,).

Measurement of the amount of acid groups and acid anhydride groups in methacrylimide-containing polymer (A) After weighing the polymer (A), it was dissolved in dimethylformamide at 50 m°C. INN qualitative potassium methanol solution was added with stirring, and the milliequivalent value was determined by neutralization titration based on conductivity.

Measurement of intrinsic viscosity of methacrylimide-containing polymer (A) Deereax-Bischoff
) Measure the flow time (t5) of a chloroform solution with a sample polymer concentration of 0.5% by weight and the flow time (to) of chloroform at 25 ± 0.1'C using a viscometer, and calculate the relative viscosity of the polymer from the tg/lo value. This is the value obtained by finding η1.1 and then calculating from the following equation.

(where C is the polymer concentration (g/100mβ))
Synthesis Example 1 Methyl methacrylate polymer (PMMA, intrinsic viscosity 0.51) was placed in a 10β reactor equipped with a paddle spiral stirrer, a pressure gauge, a sample injection container, and a jacket heater.
100 parts of methylamine, 90 parts of toluene, and 10 parts of methanol were added, heated to 250°C, stirred and dissolved, and methylamine 21.
7 parts (molar ratio to methyl methacrylate units in PMMA = 0.7) was added, and the mixture was heated and reacted at an internal pressure of 60 kg/cm"G for 3 hours. After the reaction, a methacrylimide-containing polymer (A-1) was obtained. After drying, it was powdered and used as a sample.

The imidization amount (%) of this polymer (A-1) was 70%, and the amount of acid groups was 0.45 milliequivalent.

Synthesis Example 2 Instead of the methyl methacrylate polymer, a copolymer of methyl methacrylate: methacrylic acid = 90:1 (]
．． A methacrylimide polymer (A-2) was obtained in exactly the same manner as in Synthesis Example 1, except that 60) was used. The imidization amount (%) of this polymer (A-2) was 75%, and the amount of acid groups was 0.50 milliequivalent.

Synthesis Example 3 A methacrylimide polymer (A- 3) was obtained. This polymer (A-3
) The amount of imidization (%) is 65%, and the amount of acid groups is 0.
It was 50 milliequivalent.

Examples 1 to 8 and Comparative Examples 1 to 3 Various methacrylimide-containing polymers A-1-A-3 prepared in Synthesis Examples 1 to 3 above and the following thermoplastic polyurethane B
-1-8-3 to B-1 caprolactone ester polyurethane elastomer (Nistran E-580, trade name, manufactured by Nippon Elastran Kikki) B-2 polyether polyurecne elastomer (Nistran E-380, trade name, Japan) Elastran side body) B-3 Adipate polyurethane elastomer (Nistran E-180, trade name, manufactured by Nippon Elastran Kikki) Mixed for 20 minutes in a V-type blender at the compounding ratio shown in Table 1, and then mixed in a 40 mm diameter extruder. After melt-kneading at 280℃ using a cylinder temperature of 280℃,
Various test pieces were molded at a mold temperature of 80°C.

Table 1 shows the results of evaluating the physical properties using these test pieces. The results of measuring the physical properties of methacrylimide-containing polymers (A-1-A-3) alone molded under the same conditions are also shown.

Table Examples 9 to 12 In addition to the methacrylimide-containing polymer (A) and the thermoplastic polyurethane (B), the following C components (C-1 and C-2) were added to the 60% C-1 polybutadiene rubber as impact strength improving components. A graft copolymer C-2 obtained by polymerizing 30 parts of styrene and 10 parts of acrylonitrile. Resin compositions were obtained by mixing them at the blending ratios shown in the table, and melt-kneaded and molded in the same manner as in Example 1 to evaluate various physical properties. The results are shown in Table 2.

As a result, when the impact strength improving component was added, a resin composition having even better deformation temperature, mechanical properties represented by thermal shock strength, and moldability was obtained.

[Effects of the Invention] According to the present invention, mechanical properties,
A resin composition with excellent heat resistance and moldability was obtained.

Patent applicant: Mitsubishi Rayon Co., Ltd.

Claims (1)

[Claims] 1. 1 to 99 parts by weight of a methacrylimide-containing polymer (A) containing at least 10% by weight of methacrylimide units represented by the following general formula (1) and 1 to 99 parts by weight of a thermoplastic polyurethane (B) Heat resistant, containing 99 parts by weight;
A thermoplastic resin composition with excellent impact resistance and moldability. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) (In the formula, R represents a hydrogen atom or an aliphatic, aromatic, or alicyclic hydrocarbon group having 1 to 20 carbon atoms.)