JPH0611829B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a thermoplastic resin composition in which impact resistance represented by impact strength, rigidity represented by flexural modulus and weather resistance are well balanced. It is a thing.

<Prior Art> Acrylonitrile-butadiene-styrene terpolymer resin (ABS resin) and methyl methacrylate-butadiene-styrene terpolymer resin (MBS resin) are widely used as typical impact-resistant resins. Used in the field. As a resin having improved weather resistance of these resins, an acrylonitrile-styrene graft copolymer resin (A having an ethylene-propylene rubber or an acrylic rubber as a base rubber) is used.
ES resins and AAS resins) have also been used.

On the other hand, a resin composition in which a carboxylic acid-containing olefin polymer is blended with polyamide has also been proposed for the purpose of increasing the impact of polyamide. (Japanese Patent Publication No. 42-12546, Japanese Patent Publication No. 55-44018, etc.) <Problems to be solved by the invention> However, impact-resistant resins represented by ABS resins have poor weather resistance and impact strength. However, since the flexural modulus of elasticity will be reduced when it is attempted to raise the value, it is not possible to obtain a resin having high impact resistance and high rigidity. Although AES resin and AAS resin have improved weather resistance, they cannot have high impact resistance and high rigidity like ABS resin.

A resin composition comprising a polyamide and a carboxylic acid-containing olefin polymer can obtain high impact strength, but cannot obtain a sufficient flexural modulus. In addition, the resin composition has a drawback that the flexural modulus is further significantly reduced due to moisture absorption. For the purpose of improving the hygroscopicity of polyamide, α,
A novel copolymer in which a styrene copolymer containing a β-unsaturated carboxylic acid anhydride as a copolymerization component and a polyamide are chemically bonded has also been proposed (JP-A-56-50931).
However, it is impossible to obtain a sufficiently high impact strength with this copolymer.

That is, a resin having high impact resistance, high rigidity, and excellent weather resistance has not yet been obtained, and under the present circumstances, development of a resin having these properties is desired.

The present inventors have conducted intensive studies for the purpose of developing a resin having a high impact strength and a high flexural modulus in balance and excellent weather resistance. As a result, a specific aromatic vinyl copolymer, a polyamide and a specific modified polyolefin have been obtained. The present inventors have found that the above object can be achieved by blending the above in a specific ratio, and have reached the present invention.

<Means for Solving Problems> That is, the present invention provides at least one selected from the group consisting of (A), (a) aromatic vinyl-based monomer and (meth) acrylic acid ester-based monomer. 50-99.
99 wt% and (b) 0.01 to 50 wt% of at least one vinyl monomer selected from the group consisting of α, β-unsaturated carboxylic acids and α, β-unsaturated carboxylic anhydrides.
(A) is a vinyl-based copolymer obtained by polymerizing the above, (B) polyamide, and (C) a modified polyolefin having at least one functional group selected from the group consisting of carboxylic acid groups and acid anhydride groups. To 90 parts by weight, (B) 1 to 80 parts by weight and (C) 5 to 50 parts by weight, and mixing in a ratio such that the total amount of (A), (B) and (C) is 100 parts by weight. The present invention provides a thermoplastic resin composition comprising

The thermoplastic resin composition of the present invention is a vinyl-based copolymer (A),
It is obtained by mixing the polyamide (B) and the modified polyolefin (C).

The vinyl-based copolymer (A) used in the present invention is styrene,
Aromatic vinyl monomers such as α-methylstyrene, p-methylstyrene, pt-butylstyrene, vinyltoluene, and p-chlorostyrene, and methyl methacrylate, ethyl methacrylate, tert-butyl methacrylate,
Cyclohexyl methacrylate, phenyl methacrylate,
At least one vinyl-based monomer (a) selected from the group consisting of (meth) acrylic acid ester-based monomers such as methyl acrylate, ethyl acrylate, and propyl acrylate, and acrylic acid, methacrylic acid, and maleic acid. acid,
A specific proportion of at least one vinyl monomer (b) selected from the group consisting of α, β-unsaturated carboxylic acids such as fumaric acid and itaconic acid, maleic anhydride, citraconic anhydride, and chloromaleic anhydride. Copolymerized with.
Among the above vinyl-based monomers (a), styrene, α-methylstyrene, p-methylstyrene and methyl methacrylate are particularly preferable, and these can be used alone or in combination of two or more. Among the above vinyl-based monomers (b), acrylic acid, methacrylic acid, and maleic anhydride are particularly preferable, and these may be used alone or in combination of two or more.

In the polymerization of the vinyl-based copolymer (A), the proportion of the vinyl-based monomers (a) and (b) in the (a) is 50 to 99.99% by weight, preferably 55 to 99.9% by weight, particularly preferably 65 to 99.
5 wt% and (b) 0.01 to 50 wt%, preferably
0.1 to 25% by weight, particularly preferably 0.5 to 20% by weight. When (a) is less than 50% by weight or (B) exceeds 50% by weight, the vinyl copolymer (A) is inferior in mechanical properties, thermal stability and melt fluidity, and a resin composition having desirable performance. Is not preferable because it cannot be obtained. (A) is 99.99% by weight
Or (b) is less than 0.01% by weight, the vinyl copolymer (A) is less miscible with the polyamide (B) and the modified polyolefin (C), and a resin composition having desired performance is obtained. It is not preferable because it is not available. Further, in the polymerization of the vinyl-based copolymer (A), polybutadiene (PBD),
Acrylonitrile-butadiene copolymer rubber (NB
R), styrene-butadiene copolymer rubber (SBR),
Predetermining (a) and (b) in the presence of various rubber-like polymers such as polybutyl acrylate rubber, ethylene-propylene copolymer rubber (EPR), ethylene-propylene-non-conjugated diene copolymer rubber (EPDM). It is also possible to polymerize in proportion.

The method for polymerizing the vinyl copolymer (A) is not particularly limited, and generally known methods such as bulk polymerization, solution polymerization, bulk-suspension polymerization, suspension polymerization and emulsion polymerization can be used. There is also no particular restriction on the charging method of the vinyl monomers (a) and (b), they may be charged all at once at the beginning, and in order to prevent the composition distribution of the copolymer from being generated, A part or all of them may be polymerized while being continuously charged or dividedly charged.

The polyamide (B) used in the present invention is a polyamide obtained by ring-opening polymerization of lactams such as ε-caprolactam and ω-dodecalactam, 6-aminocaproic acid, 1
Polyamides derived from amino acids such as 1-aminoundecanoic acid and 12-aminododecanoic acid, ethylenediamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4 Aliphatic such as trimethylhexamethylenediamine, 1,3- and 1,4-bis (aminomethyl) cyclohexane, bis (4,4′-aminonecyclohexyl) methane, meta and paraxylylenediamine,
Aliphatic, aromatic diamine and adipic acid, suberic acid, sebacic acid, dodecanedioic acid, 1,3- and 1,4-cyclohexanedicarboxylic acid, aliphatic such as isophthalic acid, terephthalic acid, dimer acid, alicyclic , Polyamides derived from aromatic dicarboxylic acids, copolyamides thereof, and mixed polyamides. Of these, polycaproamide (nylon 6), polyundecane amide (nylon 11), polydodecane amide (nylon 12),
Polyhexamethylene adipamide (nylon 66) and a copolyamide having these as the main components are useful.
As a method for polymerizing the polyamide, generally known melt polymerization, solid phase polymerization and a combination of these methods can be adopted.
The degree of polymerization of the polyamide is not particularly limited, and a polyamide having a relative viscosity (measured at 25 ° C by dissolving 1 g of polymer in 100 ml of 98% concentrated sulfuric acid at 25 ° C) in the range of 2.0 to 5.0 can be arbitrarily selected according to the purpose.

The modified polyolefin (C) used in the present invention is not particularly limited as long as it is a polyolefin having at least one functional group selected from the group consisting of a carboxylic acid group and an acid anhydride group. Typical examples are ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer, ethylene /
Fumaric acid copolymer, ethylene / ethyl acrylate copolymer, ethylene / ethyl acrylate / acrylic acid copolymer, ethylene / maleic anhydride copolymer, ethylene / propylene / maleic anhydride copolymer, ethylene-g -Maleic anhydride copolymer ("g" represents a graft; the same applies hereinafter), ethylene / propylene-g-maleic anhydride copolymer, ethylene / propylene-g-acrylic acid copolymer, ethylene / 1- Butene-g-fumaric acid copolymer, ethylene / 1-hexene-g-itaconic acid copolymer, ethylene / propylene-g-endobicyclo [2,2,
1] -5-heptene-2,3-dicarboxylic anhydride copolymer,
Ethylene / propylene / 1,4-hexadiene-g-maleic anhydride copolymer, ethylene / propylene / dicyclopentadiene-g-fumaric acid copolymer, ethylene / propylene / dicyclopentadiene-g-maleic anhydride copolymer Combined, ethylene / propylene / 5-ethylidene-2-
Norbornene-g-maleic anhydride copolymer, ethylene / propylene / 5-ethylidene-2-norbornene-g
-Maleic acid copolymer and ethylene / vinyl acetate-g
-Acrylic acid copolymer and the like can be mentioned, but the invention is not limited thereto. It is also possible to use two or more of these modified polyolefins in combination.

The modified polyolefin (C) is usually a known method, for example,
Japanese Patent Publication No. 39-6810, Japanese Patent Publication No. 52-43677
Japanese Patent Publication No. 53-5716, Japanese Patent Publication No. 53-1
It can be produced by the method shown in Japanese Patent Publication No. 9037, Japanese Patent Publication No. 53-41173, Japanese Patent Publication No. 56-9925.

The vinyl-based copolymer in the thermoplastic resin composition of the present invention
The compounding ratio of (A), polyamide (B) and modified polyolefin (C) is 5 to 90 parts by weight of (A), preferably 15 to 80 parts by weight, particularly preferably 20 to 70 parts by weight, and (B) is 1 ~ 8
0 parts by weight, preferably 5 to 70 parts by weight, particularly preferably 10 to 65 parts by weight, and (C) is 5 to 50 parts by weight, preferably 10 to 40 parts by weight, particularly preferably 15 to 35 parts by weight, In addition, the total amount of (A), (B) and (C) is 100 parts by weight. If the content of (A) is less than 5 parts by weight, the rigidity is poor, and if the content of (A) is more than 90 parts by weight, the impact resistance is inferior. When (B) is less than 1 part by weight or (C) is less than 5 parts by weight, impact resistance is poor, and when (B) is over 80 parts by weight or (C) is over 50 parts by weight, rigidity is poor. Therefore, it is not preferable.

The method for producing the thermoplastic resin composition of the present invention is not particularly limited, and a generally known method can be adopted.
That is, the vinyl copolymer (A), the polyamide (B) and the modified polyolefin (C) in pellets, powder, fine particles, etc., are uniformly mixed using a high-speed stirrer, etc., and then uniaxial with sufficient kneading ability. Alternatively, various methods such as a method of melt-kneading with a multi-screw extruder and a method of melt-kneading with a Banbury mixer or a rubber roll machine can be adopted. Also, vinyl-based copolymer (A) and polyamide (B), polyamide (B) and modified polyolefin (C), vinyl-based copolymer
It is also possible to preliminarily knead (A) and modified polyolefin (C) and the like, and then adjust the mixture ratio to a predetermined value and knead the mixture.

The thermoplastic resin composition of the present invention is a vinyl-based copolymer (A),
In addition to the polyamide (B) and the modified polyolefin (C), polystyrene (PS), styrene / acrylonitrile copolymer (SAN), polymethylmethacrylate (PMMA), styrene / methylmethacrylate / acrylonitrile copolymer are used as required. Combined, α-methylstyrene / acrylonitrile copolymer, α-methylstyrene / styrene / acrylonitrile copolymer, α-methylstyrene / methyl methacrylate / acrylonitrile copolymer p-methylstyrene / acrylonitrile copolymer, styrene / N Vinyl-based polymers such as phenylmaleimide copolymers, acrylonitrile-butadiene-styrene terpolymers (AB
S) resin, methacrylic acid resin-butadiene-styrene terpolymer (MBS) resin, AES resin, AAS resin,
Thermoplastic resins such as polycarbonate, polybutylene terephthalate and polyethylene terephthalate are appropriately mixed, polyethylene, polypropylene, ethylene / propylene copolymer, ethylene / butene-1 copolymer, ethylene / propylene / dicyclopentadiene copolymer, ethylene Polypropylene rubbers such as / propylene / 5-ethylidene 2-norbornene copolymer, ethylene / propylene / 1,4-hexadiene copolymer, ethylene / vinyl acetate copolymer and ethylene / butyl acrylate copolymer are appropriately mixed. By doing so, it is possible to adjust to more desirable physical properties and characteristics. Depending on the purpose, pigments and dyes, glass fibers, metal fibers, metal flakes,
Reinforcing materials and fillers such as carbon fibers, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, lubricants, plasticizers, antistatic agents and flame retardants can be added.

<Example> Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. Izod impact strength is ASTM D256
-56, Method A, flexural modulus is ASTM D790
It was measured according to -61. The weather resistance was evaluated by irradiating a notched Izod impact test piece with a Sanshear weatherometer for 400 hours and measuring the change in Izod impact strength. The Izod impact strength was measured in an absolutely dry state. The flexural modulus was 4 when the test piece was in a dry state and the test piece was in water at 23 ° C.
The measurement was carried out in a state of being immersed in water for 8 hours and treated with water absorption. Less than,
% Represents% by weight, and the number of parts represents parts by weight.

Reference Example 1 (Production of Vinyl Copolymer (A)) Vinyl copolymers (A-1) to (A-5) having the compositions shown in Table 1 were produced by the following method.

A-1: A polymerization tank was charged with 85 parts of styrene and 0.5 part of azoisobutyronitrile, and the temperature was adjusted to 80 ° C., while stirring.
A solution consisting of 15 parts of maleic anhydride and 80 parts of methyl ethyl ketone was charged at a constant rate over 8 hours. Then, the temperature was raised to 90 ° C. and kept for 2 hours. A transparent and viscous solution was obtained, and the vinyl copolymer (A-1) was produced by removing the solvent.

A-2: 48 parts of styrene, 48 parts of methyl methacrylate, 4 parts of methacrylic acid and 0.5 part of azoisobutyronitrile were charged in a polymerization tank, the temperature was adjusted to 80 ° C., and polymerization was carried out for 4 hours while stirring. It was Next, 200 parts and 0.3 part of polyvinyl alcohol (suspension stabilizer) having a saponification degree of 80% were charged, the polymerization system was transferred to a suspension state, and further at 80 ° C., 2
The granular vinyl copolymer (A-2) was produced by polymerizing at 90 ° C. for 1 hour.

Reference Example 2 (Production of Polyamide (B)) The following nylon 6, nylon 66, and nylon 12 were produced by the melt polymerization method.

Nylon 6: Relative viscosity of concentrated sulfuric acid from ε-caprolactam
2.75 nylon 6 was polymerized.

Nylon 66: Nylon 66 having a relative viscosity of concentrated sulfuric acid of 2.60 was polymerized from a molar salt of hexamethylenediamine and adipic acid.

Nylon 12: Nylon 12 having a relative viscosity of concentrated sulfuric acid of 2.35 was polymerized from 12-aminododecanoic acid.

Reference Example 3 (Production of Modified Polyolefin (C)) C-1: α, α′-dissolved in a small amount of acetone based on 100 parts by weight of an ethylene / propylene copolymer consisting of 70 mol% of ethylene and 30 mol% of propylene. Screw-
t-butylperoxy-p-diisopropylbenzene 0.
After adding 03 parts by weight and 1.0 part by weight of maleic anhydride, the mixture was kneaded at 230 ° C. using an extruder having a diameter of 40 mm to pelletize ethylene / propylene-g-
Maleic anhydride copolymer ("g" represents graft) C-1 was prepared.

C-2: To 100 parts by weight of an ethylene / propylene copolymer composed of 80 mol% of ethylene and 20 mol% of propylene, 0.1 part by weight of di-t-butyl peroxide and 1.0 part by weight of acrylic acid dissolved in a small amount of acetone were added. After the addition, an ethylene / propylene-g-acrylic acid copolymer C-2 was produced by kneading at 200 ° C. using an extruder having a diameter of 40-mmφ and pelletizing in the same manner as C-1.

C-3: ethylene with Mooney viscosity of 60 and iodine value of 12
Propylene-5-ethylidene-2-norbornene (EP
DM) terpolymer (ethylene / propylene = 68.5 / 3
1.5 (molar ratio)) to 100 parts by weight of di-t-butyl peroxide dissolved in a small amount of acetone (0.1 parts by weight) and maleic anhydride (0.5 parts by weight) were added. EPDM-g-maleic anhydride copolymer C-3 was produced by kneading at 230 ° C. using an extruder and pelletizing.

Reference Example 1 Vinyl-based copolymer (A) and polyamide (B) produced in Reference Example
The modified polyolefin (C) and the modified polyolefin (C) were mixed at a compounding ratio shown in Table 2, melt-kneaded using an extruder having a diameter of 40 mm and pelletized. The extrusion temperature was 250 ° C. when nylon 6 and nylon 12 were used as the polyamide (B), and 290 ° C. when nylon 66 was used. Then, this pellet was vacuum dried, and then a melt test piece for measuring physical properties was molded by injection molding. During injection molding, the cylinder temperature is 260 ° C when nylon 6 and nylon 12 are used as polyamide (B), and 2 when nylon 66 is used.
It was set at 90 ° C. The mold temperature was set to 80 ° C.

The measurement results are shown in Table 2.

Comparative Example Vinyl-based copolymer (A) produced in Reference Example, polyamide
(B), modified polyolefin (C) and the following vinyl copolymer were mixed with the polyolefin at the compounding ratio shown in Table 2, and the physical properties were measured by the same methods as in Example 1. The measurement results are shown in Table 2.

Vinyl-based (co) polymer A-3: polystyrene A-4: copolymer polyolefin consisting of 72% by weight of styrene and 28% by weight of acrylonitrile C-4: ethylene / propylene consisting of 70 mol% of ethylene and 30 mol% of propylene. Copolymer C-5: ethylene with Mooney viscosity of 60 and iodine value of 12
Propylene-5-ethylidene-2-norbornene (EP
DM) terpolymer (ethylene / propylene = 68.5 / 3
1.5 (molar ratio)) The following is clear from the results of Example 1 and Comparative Example. All of the resin compositions (No. 1 to No. 10) of the present invention have high Izod impact strength and flexural modulus. Izod impact strength is 400 with Sunshine Weathermeter
It has excellent weather resistance with little deterioration even after irradiation for a long time. The flexural modulus remains relatively high even after water absorption treatment. That is, the resin composition of the present invention is a resin composition having high impact resistance, high rigidity and excellent weather resistance. On the other hand, a resin composition containing only a vinyl-based copolymer (A) containing no polyamide and a modified polyolefin (C) (Comparative Example No. 1,
2) has low impact strength. The resin composition (Comparative Examples Nos. 3 and 4) consisting of the polyamide (B) not containing the vinyl copolymer (A) and the modified polyolefin (C) has a low flexural modulus.
The flexural modulus is further significantly reduced by the water absorption treatment.
Vinyl-based copolymer (A) containing no modified polyolefin (C)
And a resin composition consisting of polyamide (B) only (Comparative Example No.
5) has low impact strength. Modified Polyolefin (C) 50
The composition (Comparative Example No. 6) containing more than the above parts is not preferable because the flexural modulus is low. A composition containing more than 80 parts of the polyamide (B) (Comparative Example No. 7) is not preferable because the impact strength is low and the flexural modulus is significantly lowered by the water absorption treatment. Α, β in vinyl copolymer (A)
A resin composition containing no unsaturated carboxylic acid (anhydride) (Comparative Examples Nos. 8 and 9) and a resin composition containing no carboxylic acid group, metal carboxylate group or acid anhydride group in the modified polyolefin (C). The products (Comparative Examples Nos. 10 and 11) have low impact strength.

Example 2 Vinyl Copolymer (A) and Polyamide Produced in Reference Example
(B), modified polyolefin (C), the vinyl-based (co) polymer shown in Comparative Example, and polyolefin were mixed in the compounding ratio shown in Table 2, and the physical properties were measured by the same method as in Example 1.

The measurement results are shown in Table 2. In addition to vinyl-based copolymer (A), polyamide (B) and modified polyolefin (C), vinyl-based (co) polymer such as styrene / acrylonitrile copolymer and ethylene / propylene copolymer rubber (E
PR) such as polyolefin rubber can be mixed to obtain a desirable resin composition having excellent impact strength, flexural modulus and weather resistance.

<Effects of the Invention> As described above, the resin composition of the present invention is a resin composition excellent in both impact resistance represented by impact strength, rigidity represented by flexural modulus and weather resistance. This effect is first exhibited by mixing the vinyl copolymer (A), the polyamide (B) and the modified polyolefin (C) in the specific proportions of the present invention.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C08L 33/08 LJB 7921-4J LJE 7921-4J 51/06 LLE 7142-4J 77/00 LQS 9286- 4J // (C08L 25/08 77:00 23:02) (C08L 33/08 77:00 51:06) (56) Reference JP-A-59-27940 (JP, A)

Claims (1)

[Claims] 1. At least one vinyl-based monomer selected from the group consisting of (A), (a) aromatic vinyl-based monomer and (meth) acrylic acid ester-based monomer.
99% by weight and 0.01 to 50% by weight of at least one vinyl monomer selected from the group consisting of (b) α, β-unsaturated carboxylic acid and α, β-unsaturated carboxylic acid anhydride. The modified polyolefin having at least one functional group selected from the group consisting of a vinyl-based copolymer obtained by polymerization, (B) polyamide and (C) carboxylic acid group and acid anhydride group is (A) 5 to 5 90 parts by weight, (B) is 1 to
A thermoplastic resin composition obtained by mixing 80 parts by weight and (C) in an amount of 5 to 50 parts by weight and a total amount of (A), (B) and (C) being 100 parts by weight.