JP2618626B2 - Method for producing thermoplastic resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a novel thermoplastic resin composition that can be used as a molded product, sheet, film, or the like by injection molding or extrusion molding.

More specifically, a modified ethylene copolymer containing partially ionized acid anhydride groups is blended in a polyamide resin, or an ethylene copolymer containing acid anhydride groups in a polyamide resin and a metal ion generator The present invention relates to a novel thermoplastic resin composition having excellent balance of physical properties and appearance in which acid anhydride groups are partially ionized at the same time.

[Conventional technology]

Generally, polyamide resins are widely used as engineering plastics because of their excellent rigidity, abrasion resistance, chemical resistance, heat resistance, and electrical properties.

However, they have difficulties or need improvement in impact resistance, molding stability, etc., and these are obstacles in cultivating practical applications.

Various methods have been proposed to improve the impact resistance, which is a disadvantage of such polyamide resins.

For example, as a typical method, as described in JP-B-54-4743, JP-B-55-44108, and JP-A-58-23850, an active group and a rubber capable of reacting with a polyamide resin are used. A method of adding a modified ethylene copolymer type polymer having elasticity may, for example, be mentioned.

However, according to the study results of the present inventors, it is possible to obtain a molded article having relatively improved impact resistance in the above-mentioned conventional technique, but it is still insufficient. In addition, rigidity,
It was found that it was not satisfactory from the viewpoint of the balance of physical properties of impact resistance.

That is, its somewhat improved impact resistance and flexibility is offset by significantly poorer mechanical properties than the polyamide resin itself, such as stiffness, tensile strength, hardness, and the like. Further, there are many problems that molded articles having a colored appearance and inferior appearance are often obtained, which limits the application.

Therefore, it is important to select a modified ethylene copolymer type polymer to be added to the polyamide resin, which does not cause the above-mentioned problems, and its development is strongly desired.

[Problems to be solved by the invention]

The present invention solves the above-mentioned problems without impairing mechanical properties such as rigidity by applying a modified ethylene copolymer having a specific structure in improving the impact resistance, which is a drawback of such a polyamide resin. It is an object of the present invention to provide a thermoplastic resin composition containing a polyamide resin as a main component and having excellent impact resistance and excellent mechanical properties such as rigidity.

[Means for Solving the Problems] The present inventors have extensively and carefully searched for a polymer effective for modifying the polyamide resin from this viewpoint, and as a result, a modified ethylene copolymer having a specific structure was found to be effective. In particular, they have found that the balance between impact resistance and rigidity is good, and that they are excellent in terms of moldability and appearance of molded products, and have reached the present invention.

That is, the present invention relates to (A) 50 to 97% by weight of a polyamide resin, (B) 50 to 90% by weight of ethylene, 5 to 49% by weight of an α, β-unsaturated carboxylic acid alkyl ester and 0.1% of maleic anhydride.
5 to 10% by weight of an ethylene copolymer and 50 to 3% by weight of a modified ethylene copolymer obtained by a neutralization reaction of maleic anhydride with 5 to 80% by mole of a metal ion generator. A method for producing a thermoplastic resin composition, comprising: in the presence of a polyamide resin, ethylene 50 to 90% by weight, α,
an ethylene copolymer comprising 5-49% by weight of β-unsaturated carboxylic acid alkyl ester and 0.5-10% by weight of maleic anhydride, and 5-80 mol% of a metal ion generator based on maleic anhydride; An object of the present invention is to provide a method for producing a thermoplastic resin composition, which comprises kneading all at once.

Further, the present invention relates to (A) 50 to 97% by weight of a polyamide resin, (B) 50 to 90% by weight of ethylene, 5 to 49% by weight of an α, β-unsaturated carboxylic acid alkyl ester and 0.4% of maleic anhydride.
5 to 10% by weight of an ethylene copolymer and 50 to 3% by weight of a modified ethylene copolymer obtained by a neutralization reaction of maleic anhydride with 5 to 80% by mole of a metal ion generator. A method for producing a thermoplastic resin composition, comprising 50 to 90% by weight of ethylene, 5 to 49% by weight of an α, β-unsaturated carboxylic acid alkyl ester and 0.5 to 10% of maleic anhydride.
% Of a modified ethylene copolymer obtained by a neutralization reaction with 5 to 80 mol% of a metal ion generator with respect to maleic anhydride, and 50 to 3% by weight of a polyamide resin. It is intended to provide a method for producing a thermoplastic resin composition, comprising kneading 97% by weight.

Component (A) polyamide resin in the present invention includes 3
Various polyamides obtained by polycondensation of a lactam having at least a member ring, a polymerizable ω-amino acid, a dibasic acid and a diamine can be used.

Specifically, polymers such as ε-caprolactam, aminocaproic acid, enantholactam, 7-aminoheptanoic acid, 11-aminoundecanoic acid, or hexamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine Polymers obtained by polycondensation of diamine acids such as methacrylate, metaxylenediamine and dicarboxylic acids such as terephthalic acid, isophthalic acid, adipic acid, sebacic acid, dodecane dibasic acid and glutaric acid, or copolymers thereof. Coalescence.

Specific examples include polyamide 6, polyamide 6.6, polyamide 6.10, polyamide 11, polyamide 12, polyamide 6.12,
And aromatic polyamide resins such as polyhexamethylene diamine terephthalamide, polyhexamethylene isophthalamide, and xylene group-containing polyamide.

Of these, polyamide 6 and polyamide 6.6 are industrially important.

In the thermoplastic resin composition according to the present invention, the polyamide resin as the component (A) is contained in an amount of 50 to 97% by weight, preferably 60 to 92% by weight, and more preferably 70 to 90% by weight.

Therefore, the modified ethylene copolymer as the component (B) is contained in an amount of 3 to 50% by weight, preferably 8 to 40% by weight, more preferably 10 to 30% by weight.

If the polyamide resin component (A) is less than 50% by weight, rigidity and heat resistance are not sufficient, and if it exceeds 97% by weight, favorable results in impact resistance cannot be obtained.

Component (B), a modified ethylene copolymer, which is one of the constituent components of the resin composition according to the present invention, is characterized in that its monomer component is ethylene, α, β-unsaturated carboxylic acid alkyl ester,
And 50 to 90% by weight, preferably 60 to 85% by weight, of the α, β-unsaturated carboxylic acid alkyl ester of 5 to 90% by weight of a partially ionized maleic anhydride.
49% by weight, preferably 7-45% by weight, and 0.5-10% by weight, preferably 1-8% by weight, of partially ionized maleic anhydride.

α, β-unsaturated carboxylic acid alkyl esters are unsaturated carboxylic acids having 3 to 8 carbon atoms, for example, acrylic acid,
And alkyl esters such as methacrylic acid. Specific examples include ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate,
T-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate, n-methacrylate
Propyl, isopropyl methacrylate, n-methacrylic acid
-Butyl, t-butyl methacrylate, and isobutyl methacrylate, among which ethyl acrylate, n-butyl acrylate, and methyl methacrylate are particularly preferred.

Suitable metal species for the partial metal ionization of maleic anhydride include IA, IB, IIA, IIB, IIIA, and V in the Periodic Table of the Elements.
Group III period 4 metals such as Na, K, Cu, Mg, C
a, Ba, Zn, Cd, Al, Fe, Co, and Ni, among which Na, K, Mg, Ca, Ba, and Zn are particularly preferable.

Metal ion generators include various organic acid salts, oxides, hydroxycarbonates, free metals, metal hydrides,
Metal alkoxide or organic metal
Among these, an organic carboxylate or an amino acid salt is particularly preferred.

Specifically, metal salts of higher aliphatic carboxylic acids having 10 to 24 carbon atoms such as capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, and lignoceric acid, or aspartic acid and glutamic acid And metal salts of various amino acids. Among these, metal salts of stearic acid or glutamic acid are preferred.

There is no particular limitation on the method of the neutralization reaction between such a producing agent and an ethylene copolymer containing a maleic anhydride group. For example, a method of directly melt-kneading the mixture in a Banbury mixer, an extruder, or a roll is convenient.

The component (B) modified ethylene copolymer used in the present invention may be one in which maleic anhydride, which is a constituent monomer thereof, may be partially metal-ionized in advance, but for the resin composition of the present invention, It is not always important whether component (B) has been ionized beforehand.

That is, the resin composition formed by directly kneading the component (B) modified ethylene copolymer with the component (A) polyamide resin and the metal ion generator in the presence of the polyamide resin is also included in the present invention. It serves the purpose and is industrially very significant.

The amount of the metal ion generator is preferably 5 to 80 mol%, more preferably maleic anhydride.
10-70 mol%. If the amount of generated metal ions is less than 5 mol%, the cold resistance, especially the impact resistance at low temperatures is inferior, and 80 mol%.
Above this, impact resistance decreases.

In the modified ethylene copolymer (B), ethylene is 50
If the amount is less than 90% by weight, the rigidity is greatly reduced when the composition is made with a polyamide, and if the amount exceeds 90% by weight, a favorable result in impact resistance cannot be obtained.

On the other hand, if the amount of the α, β-unsaturated carboxylic acid alkyl ester is less than 5% by weight or more than 49% by weight, favorable results in impact resistance cannot be obtained.

In addition, 0.5% of partially ionized maleic anhydride is used.
If the content is less than 10% by weight, favorable results cannot be obtained in impact resistance, and if it exceeds 10% by weight, favorable results in impact resistance and moldability cannot be obtained.

The modified ethylene copolymer (B) has a melt index (JIS K6760) of 1 to 100 g / 10 minutes, preferably 2 to 100 g / 10 minutes.
The range is 50g / 10 minutes. Melt index 100g / 10
If the amount exceeds 1 minute, it is not preferable from the viewpoint of mechanical properties of the composition, and if it is less than 1 g / 10 minutes, the compatibility with the polyamide is lacking.

The resin composition of the present invention may further contain, if necessary, a fibrous reinforced composite material such as glass fiber, carbon fiber, and metal whisker, silica, alumina, calcium carbonate, talc, mica, carbon black, TiO
_2, ZnO, and Sb inorganic fillers such as ₂ O _3, or a flame retardant agent, more lubricants, nucleating agents, plasticizers, dyes, pigments, antistatic agents, antioxidants, weather resistance imparting agent In some cases, it is preferable to use it as an added composite material.

The method for producing the resin composition of the present invention is not particularly limited, and an ordinary known method can be used. From an industrial point of view, in practice, a method of kneading in a molten state is used.

For the melt-kneading, kneading apparatuses generally used such as a Banbury mixer, an extruder, a roll and various kneaders can be used. When kneading, it is preferable that each resin component is uniformly mixed in advance in the form of a powder or pellets using a device such as a tumbler or a Henschel mixer. However, if necessary, mixing is omitted and kneading is performed. It is also possible to use a method of separately supplying a fixed amount to each device.

The kneaded resin composition is molded by injection molding, extrusion molding, or other various molding methods. However, the present invention also provides a dry-blending process during injection molding or extrusion molding without a kneading step. And a method of directly kneading the mixture into a molded product.

〔Example〕

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.

The Izod impact strength (sample thickness)
3.2mm, measurement temperature 23 ℃ and -30 ℃, with V-notch) is JIS
The K7110 has a flexural modulus (sample thickness 3.2 mm, measurement temperature 23
℃), JIS K7203, melt index (190 ℃, 2160
g) was performed according to JIS K6760, respectively.

In the examples and comparative examples, the following were used as the polyamide resin and the ethylene copolymer.

1) Polyamide resin PA-1: Ube Industries, Ltd., UBE nylon 2020B (polyamide-6.6) PA-2: Ube Industries, Ltd., UBE nylon 1013B (polyamide-6) 2) Ethylene copolymer The ethylene copolymers (a), (b),
(C) and (d) can be prepared by the methods described in French Patent No. 1,323,379 and French Patent Application No. 81 / 01,430.

Ethylene copolymer (a): manufactured by Sumika CFD Inc.
Bondyne AX8040 (E / BA / MAH = 64.4 / 33.8 / 1.8% by weight,
MI: 4.1 g / 10 minutes) Ethylene copolymer (b): manufactured by Sumika CFD Inc.
Bondyne AX8060 (E / EA / MAH = 70.7 / 26 / 3.3 wt%, M
I: 40g / 10min) Ethylene copolymer (c): ethylene-ethyl acrylate
To-maleic acid monomethyl ester copolymer (E / EA / MAM
E = 67 / 30.5 / 2.5% by weight, MI: 1.0 g / 10 min) Ethylene polymer (d): ethylene-butyl acrylate
Copolymer (E / BA = 70/30% by weight, MI: 9.0 g / 10 min) where E: ethylene, BA: butyl acrylate, EA: ethyl
Ruacrylate, MAH: maleic anhydride, MAME: maleic acid
Monomethyl ester, MI: indicates melt index.

3) Modified ethylene copolymer Ethylene copolymer (a), (b) or (c) is blended with sodium stearate, sodium laurate, or sodium glutamate, respectively, in the proportions shown in Table 1, with a 30 mmφ single shaft vent. Using an extruder, modified ethylene copolymers A, B, C, D, E, F and G were obtained by pelletizing by melt kneading at a temperature of 230 ° C.

Examples 1 to 20 and Comparative Examples 1 to 12 Using a single screw extruder with a 30 mmφ vent, a predetermined temperature (280 ° C. for polyamide 6.6, 245 ° C. for polyamide 6)
C) to obtain various resin compositions as shown in Tables 2 and 3.

After drying each resin composition at a temperature of 80 ° C. for 12 hours, a 10-ounce injection molding machine (Toshiba IS-1) was used as a molding material.
50E-V type) at a certain temperature (for polyamide 6.6,
280 ° C, 245 ° C for polyamide 6) and a mold temperature of 70 ° C to prepare test pieces for measuring physical properties.

The test results of Izod impact strength and flexural modulus of the obtained test piece were as shown in Tables 2 and 3.

It can be seen from the comparison with the comparative example that the effect of modifying the polyamide resin by the modified ethylene copolymer in the present invention is remarkable.

Examples 21 to 23 Polyamide resin PA-1, or PA-2 was prepared by mixing ethylene copolymer (a) and sodium stearate with
Various resin compositions were blended in the proportions shown in the table and at a predetermined temperature (280 ° C. for polyamide-6.6, 245 ° C. for polyamide-6) using an extruder with a 30 mmφ single screw vent.

For each resin composition, a test piece for measuring physical properties was prepared in the same manner as in Example 1.

The test results of Izod impact strength and flexural modulus of the obtained test piece are as shown in Table 4.

From the results shown in Table 4, it is possible to obtain a polyamide resin composition having a high Izod impact strength by a method of simultaneously ionizing when kneading with a polyamide resin without using a modified ethylene copolymer partially ionized in advance. You can see that.

[Effects of the Invention] The thermoplastic resin composition of the present invention not only has good moldability, but also has a remarkable effect in that the properties of molded articles are well balanced.

The novel resin composition provided by the present invention can be easily formed into molded articles, films, sheets, and the like by molding methods used for ordinary polyamide-based thermoplastic resin compositions, for example, molding methods such as injection molding and extrusion molding. Processed to give a product with excellent balance of physical properties such as impact resistance, stiffness, heat resistance and chemical resistance, with excellent appearance uniformity and smoothness.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor, Hitoshi Ninari 5-1, Anesaki Beach, Ichihara City Within Sumitomo Chemical Co., Ltd. (56) References JP-A-60-69159 (JP, A)

Claims (2)

(57) [Claims] (A) 50 to 97% by weight of a polyamide resin (B) 50 to 90% by weight of ethylene, 5 to 49% by weight of an α, β-unsaturated carboxylic acid alkyl ester and 0.5% of maleic anhydride.
5 to 10% by weight of an ethylene copolymer and 50 to 3% by weight of a modified ethylene copolymer obtained by a neutralization reaction of maleic anhydride with 5 to 80% by mole of a metal ion generator. A method for producing a thermoplastic resin composition, comprising: in the presence of a polyamide resin, ethylene 50 to 90% by weight, α,
an ethylene copolymer comprising 5-49% by weight of β-unsaturated carboxylic acid alkyl ester and 0.5-10% by weight of maleic anhydride, and 5-80 mol% of a metal ion generator based on maleic anhydride; A method for producing a thermoplastic resin composition, comprising kneading all at once. 2. (A) 50 to 97% by weight of a polyamide resin (B) 50 to 90% by weight of ethylene, 5 to 49% by weight of an α, β-unsaturated carboxylic acid alkyl ester and 0.1% of maleic anhydride.
5 to 10% by weight of an ethylene copolymer and 50 to 3% by weight of a modified ethylene copolymer obtained by a neutralization reaction of maleic anhydride with 5 to 80% by mole of a metal ion generator. A method for producing a thermoplastic resin composition, comprising 50 to 90% by weight of ethylene, 5 to 49% by weight of an α, β-unsaturated carboxylic acid alkyl ester and 0.5 to 10% of maleic anhydride.
% Of a modified ethylene copolymer obtained by a neutralization reaction with 5 to 80 mol% of a metal ion generator with respect to maleic anhydride, and 50 to 3% by weight of a polyamide resin. 97% by weight of a thermoplastic resin composition.