JPS61171751A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition having excellent weather resistance and high and balanced impact strength and flexural modulus, by compounding a specific vinyl copolymer, a polyamide and a specific modified polyolefin. CONSTITUTION:The objective composition is produced by compounding (A) 5-90pts.(wt.) of a vinyl copolymer composed of (i) 50-99.99(wt)% vinyl monomer selected from an aromatic vinyl monomer and a (meth)acrylate monomer, (ii) 0.01-50% alpha,beta-unsaturated carboxylic acid (anhydride) and (iii) 0-45% other copolymerizable vinyl monomer with (B) 1-80pts. of a polyamide and (C) 5-50pts. of a modified polyolefin having a group selected from carboxyl group, metal carboxylate group and acid anhydride group. The preferable ratios of A:B:C (pts.wt.) are (20-70):(10-65):(15-35).

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a thermoplastic resin composition that is well-balanced and excellent in impact resistance represented by impact strength, rigidity represented by flexural modulus, and weather resistance. It is something.

<Prior art> As typical impact-resistant resins, acrylonitrile-butadiene-styrene terpolymer resin (ABS resin) and methyl methacrylate-butadiene-styrene terpolymer resin (CMBS resin) are used in a wide range of fields. used in As a resin with improved weather resistance of these resins, acrylonitrile-styrene graft copolymer resin (A
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 the 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 such as ABS resin have poor weather resistance and low impact strength. If an attempt is made to increase the flexural modulus, the flexural modulus will decrease, making it impossible to obtain a resin with high impact resistance and high rigidity.

Although ABS resins, AAS resins, and the like have improved weather resistance, they cannot provide the same high impact resistance and high rigidity as ABS resins.

Although a resin composition made of polyamide and a carboxylic acid-containing olefin polymer can obtain high impact strength, it cannot obtain sufficient flexural modulus.

Moreover, the resin composition has the disadvantage that its flexural modulus further decreases significantly due to moisture absorption.

A new copolymer in which polyamide is chemically bonded to a styrene copolymer containing α,β-unsaturated carboxylic acid anhydride as a copolymerization component has also been proposed for the purpose of improving the hygroscopic properties of polyamide. However, depending on the copolymer, sufficiently high impact strength cannot be obtained.

That is, a resin with high impact strength, high rigidity, and excellent weather resistance has not yet been obtained, and there is currently a desire to develop a resin that has both of these properties.

As a result of extensive research aimed at developing resins that have balanced high impact strength and flexural modulus, and excellent weather resistance, the inventors have found that a specific aromatic vinyl copolymer, a polyamide, and a specific modified polyolefin. It has been discovered that the above object can be achieved by blending in a specific ratio, and the present invention has been achieved.

Means for Solving the Problems> That is, the present invention provides at least one compound selected from the group consisting of N, (a) an aromatic vinyl monomer, and a (meth)acrylic acid ester monomer. 50 to 99.99% by weight of a vinyl monomer; (b) at least one vinyl monomer selected from the group consisting of α,β-unsaturated carboxylic acid and α,β-unsaturated carboxylic acid anhydride; 0.0
1-50% by weight and? 1), (a) and/or (
b) Other vinyl monomers copolymerizable with 0 to 45% by weight
(B) a polyamide and (C) a modified polyolefin having at least one functional group selected from the group consisting of a carboxylic acid group, a carboxylic acid metal base, and an acid anhydride group. (A) is 5 to 90 parts by weight, (B) is 1 to 80 parts by weight, [C] is 5 to 50 parts by weight, and the total amount of N, (B) and (C) is 100 parts by weight.
The object of the present invention is to provide a thermoplastic resin composition which is mixed in a ratio of fi parts.

The thermoplastic resin composition of the present invention is obtained by mixing vinyl copolymer N, polyamide B) and modified polyolefin (q).

The vinyl copolymer (A) used in the present invention includes styrene, α-methylstyrene, p-methylstyrene, p-t-
Aromatic vinyl monomers such as butylstyrene, vinyltoluene, p-chlorostyrene, methyl methacrylate, ethyl methacrylate, t-butyl methacrylate,
cyclohexyl methacrylate, phenyl methacrylate,
At least one vinyl monomer (a) selected from the group consisting of (meth)acrylic acid ester monomers such as methyl acrylate, ethyl acrylate, and propyl acrylate, acrylic acid, methacrylic acid, and maleic acid. at least one vinyl monomer (01 and the necessary Depending on (a) and/or (
B) is copolymerized with other copolymerizable vinyl monomer e＼) in a specific ratio.・The above vinyl monomer (A)
Among these, styrene, α-methylstyrene, p-methylstyrene, and methyl methacrylate are particularly preferred, and one or more of these can be used in combination.

Among the vinyl monomers (b), acrylic acid, methacrylic acid, and maleic anhydride are particularly preferred, and these may be used alone or in combination of two or more. The vinyl monomer (c) is not particularly limited as long as it is copolymerizable with (a) and/or (b) and is a vinyl monomer other than (i) and -), such as acrylonitrile, Vinyl cyanide monomers such as methacrylonitrile, N-
Maleimide monomers such as phenylmaleimide can be mentioned.

In the polymerization of vinyl copolymer N, the proportions of vinyl monomers (a), (b), and (c) are 50 to 99.
99% by weight, preferably 55-99.9% by weight, particularly preferably 65-99.5% by weight, (Ol is 0.01-5
0ft, M96, preferably 0.1 to 25% by weight, particularly preferably 0.5 to 20% by weight and 0 to 45% by weight, preferably 0 to 40% by weight, particularly preferably 0 to 20% by weight.
It is 35% by weight. (a) is less than 50% by weight, or -
) exceeds 50% by weight, or (c) exceeds 45% by weight, the vinyl copolymer (A) has poor mechanical properties, thermal stability, and melt fluidity, resulting in a resin composition with desirable performance. This is not desirable because it is not possible to obtain If (a) exceeds 99.99% by weight, or (b) is 0.0
If it is less than 1% by weight, the miscibility of the vinyl copolymer (A) with the polyamide (B) and modified polyolefin C) will be poor and a resin composition with desired performance will not be obtained, which is not preferable. In addition, in the polymerization of vinyl copolymer ■,
Polybutadiene (PBD), acrylonitrile-butadiene copolymer rubber (NBR), styrene-butadiene copolymer rubber (SBR), polybutyl acrylate rubber, ethylene-propylene copolymer rubber (EPR'I, ethylene-propylene-nonconjugated) Diene copolymer rubber (EPD
(A) and (B) in the presence of various rubbery polymers such as M).
It is also possible to polymerize and (c) in a predetermined ratio.

There are no restrictions on the method of polymerizing the vinyl copolymer, including bulk polymerization, solution polymerization, and bulk polymerization. ,□□,1□8
45o□. ka i [method is used. There is no particular restriction on the method of charging the vinyl monomers k), (o), and rll, and they may be charged all at once at the initial stage. Part or all of the ingredients may be added continuously or in divided portions.

The polyamide used in the present invention (81 refers to polyamide obtained by ring-opening polymerization of lactams such as C-caprolactam and ω-dodecalactam, 6-aminocaproic acid,
Polyamides derived from amino acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid, ethylenediamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2.4-/2,4.4 - aliphatic, cycloaliphatic, such as trimethylhexamethylene diamine, 1,3- and 1,4-bis(aminomethyl)cyclohexane, bis(4,4'-aminocyclohexyl)methane, meta- and para-xylylene diamine, Aromatic diamines and adipic acid, speric acid, sepacic acid, dodecanoic acid, 1.3-
and polyamides derived from aliphatic, alicyclic, and aromatic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, and dimer acid, and copolymerized polyamides and mixed polyamides thereof. Among these, usually polycapro, amide (nylon 6),
Polyundecaneamide (nylon 11), polydodecanamide (nylon 12), polyhexamethylene adipamide (nylon 66), and copolyamides containing these as main components are useful. The polymerization method of polyamide can be generally known melt polymerization, solid phase polymerization, or a combination of these methods.The degree of polymerization of polyamide is not particularly limited.
Depending on the purpose, polyamides having a melting point of 2.0 to 5.0 (measured at 25° C.) can be arbitrarily selected.

The modified polyolefin (C) used in the present invention is not particularly limited as long as it has at least one functional group selected from the group consisting of a carboxylic acid group, a carboxylic acid metal base, and an acid anhydride group. As a representative example,
Ethylene/acrylic acid copolymer, ethylene/methacrylic acid copolymer, ethylene/fumaric acid copolymer, ethylene/
Methacrylic acid/zinc methacrylate copolymer, ethylene/acrylic acid/sodium methacrylate copolymer, ethylene/isobutyl acrylate/methacrylic acid/zinc methacrylate copolymer, ethylene/methyl methacrylate/methacrylic acid/methacrylic acid Magnesium 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 graft. ), ethylene/propylene-g-maleic anhydride copolymer, ethylene/propylene-g-acrylic acid copolymer, ethylene/1-butene-g-7 malic 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, ethylene/propylene 15-ethylidene-2-norbornene-g
-Maleic anhydride copolymer, ethylene/propylene 15
Examples include, but are not limited to, -ethylidene-2-normerene-g-maleic acid copolymer and ethylene/vinyl acetate-g-7 acrylic acid copolymer. It is also possible to use two or more of these modified polyolefins in combination.

The modified polyolefin C) is usually prepared by known methods, e.g.
Special Publication No. 39-6810, Special Publication No. 52-43677
It can be produced by the method disclosed in Japanese Patent Publication No. 53-5716 f, Japanese Patent Publication No. 53-19037, Japanese Patent Publication No. 41173-1973, and Japanese Patent Publication No. 56-9925. Regarding ethylene ionomers, ``Surlyn'' and ``Heimilan'' are generally used.
, various grades commercially available under the trade name 'Copolene' can be used.

In the thermoplastic resin composition of the present invention, vinyl copolymer (A), polyamide CB) and modified polyolefin (
The blending ratio of (A) is 5 to 90 parts by weight, preferably 15 parts by weight.
~80 parts by weight, particularly preferably 20-70 parts by weight, Q3
) is 1 to 80 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 1
The ratio is 5 to 35 parts by weight, and the total amount of (trans), (81 and C) is 100 parts by weight. If the content of (A) is less than 5 parts by weight, the rigidity will be poor, and if the content (A) exceeds 90 parts by weight, the impact resistance will be poor, which is not preferable. If 03) is less than 1 part by weight or C) is less than 5 parts by weight, the impact resistance will be poor;
) exceeds 80 parts by weight, or C) exceeds 50 parts by weight, which are undesirable because the rigidity is poor.

There are no particular limitations on the method for producing the thermoplastic resin composition of the present invention, and generally known methods can be employed.

That is, after uniformly mixing vinyl copolymer (transfer), polyamide (B), and modified polyolefin C) in the form of pellets, powder, or small pieces using a high-speed stirrer, etc., a uniaxial or A gentle method such as a method of melt-kneading using a shaft extruder or a method of melt-kneading using a Banbury mixer or a rubber roll machine can be adopted. In addition, vinyl copolymer (transfer) and polyamide (B), polyamide (Bl and modified polyolefin C),
It is also possible to pre-knead the vinyl polymer (A) and the modified polyolefin C), and then adjust the mixing ratio to a predetermined mixing ratio and knead them.

The thermoplastic resin composition of the present invention is a vinyl copolymer (A)
, polyamide @) and modified polyolefin C), polystyrene (PS), styrene/acrylonitrile copolymer (sAN), polymethyl methacrylate (PMMA), styrene/methyl methacrylate/
Acrylonitrile copolymer, α-methylstyrene/acrylonitrile copolymer, a-methylstyrene/styrene/acrylonitrile copolymer, a-mef Jl/styrene/methyl methacrylate/acrylonitrile copolymer, p-methylstyrene/ Vinyl polymers such as acrylonitrile copolymer, styrene/N-phenylmaleimide copolymer, acrylonitrile-butadiene-styrene terpolymer (ABS) resin, methacrylic acid resin-butadiene-styrene terpolymer (MBS) )mflll, AE
S resin, AAS resin, polycarbonate, polybutylene terephthalate, polyethylene terephthalate and other thermoplastic resins appropriately mixed, polyethylene, polypropylene, ethylene/propylene copolymer, ethylene/butene-1 copolymer, ethylene/propylene/dicyclo Pentadiene copolymer, ethylene/propylene 15-ethylidene 2-norbornene copolymer, ethylene/propylene/1,4-hexadiene copolymer, ethylene/vinyl acetate copolymer and ethylene/butyl acrylate copolymer, etc. By appropriately mixing polyolefin rubber, it is also possible to adjust the physical properties and characteristics to more desirable values. Depending on the purpose, reinforcing materials and fillers such as pigments, dyes, glass fibers, metal fibers, metal flakes, and carbon fibers, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, lubricants, plasticizers, and electrostatic charges are also added. Inhibitors, flame retardants, etc. can be added.

<Examples> Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. Izotsu impact strength is ASTM D256
-56, Method A, flexural modulus is ASTM
Measured according to D790-61. Weather resistance was evaluated by irradiating a notched Izot impact test piece with a sunshine weatherometer for 400 hours and measuring the change in impact strength. Izot impact strength was measured in an absolutely dry state. The flexural modulus was measured in an absolutely dry state and in a state in which the test piece was immersed in water at 23° C. for 48 hours to absorb water. Hereinafter, % means % by weight, and parts represent parts by weight.

Reference Example 1 (Production of vinyl copolymer (A)) A vinyl copolymer (A) having the composition shown in Table 1 was produced by the following method.
-1) to (A-5) were manufactured.

A-1: Pour 85 parts of styrene and 0.5 parts of azoisobutyronitrile into a M gold type, adjust the temperature to 80°C, and add a solution consisting of 15 parts of maleic anhydride and 80 parts of methyl ethyl ketone for 8 hours while stirring. It was prepared at a constant speed.

Then, the temperature was raised to 90°C and held for 2 hours. A transparent and viscous solution was obtained, and by removing the solvent, a vinyl copolymer (A-1) was produced. Add 0.5 part of nitrile, adjust the temperature to 80°C, and add 7 parts of acrylonitrile while stirring.
．． 4 parts of a solution consisting of 5 parts of maleic anhydride and 0.5 part of maleic anhydride.
It was fed at a constant speed over time. Next, 200 parts of water and 0.3 parts of polyvinyl alcohol (suspension stabilizer) with a degree of saponification of 8096 were charged, the polymerization system was transferred to a suspended state, and the polymerization was further carried out at 80°C for 2 hours and at 90°C for 1 hour. A granular vinyl copolymer (A-2) was produced.

A-3 = A polymerization tank was charged with 74 parts of styrene, 24 parts of acrylonitrile, 2 parts of acrylic acid, and 0.5 parts of azoisobutyronitrile, and the temperature was adjusted to 80°C, and polymerization was carried out for 4 hours with stirring. Next, the mixture was transferred to a suspension state in the same manner as in (A-2), and suspension polymerization was performed to produce a granular vinyl copolymer (A-3).

A-4: Granular vinyl copolymer (A-4) was produced in the same manner as (A-3') except that 48 parts of styrene, 48 parts of methyl methacrylate, and 4 parts of methacrylic acid were used as the vinyl monomers. was manufactured.

A-5: fi polymerization tank 35 parts of styrene, 35 parts of α-methylstyrene, 20 parts of acrylonitrile, maleic anhydride I
Charge ON and 0.5 part of azoisobutyronitrile,
Polymerization was carried out at 75° C. with stirring for 7 hours. onwards,(
Transfer to a suspension state and polymerize in the same manner as A-2),
A granular vinyl copolymer (A-5) was produced.

Table 1 MAH: Maleic Anhydride 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: Nylon 6 having a relative viscosity of 2.75 was polymerized from C-caprolactam using concentrated sulfuric acid.

Nylon 66: Nylon 66 having a relative viscosity of 2.60 was polymerized from an equimolar salt of hexamethylene diamine and adipic acid in concentrated sulfuric acid.

Nylon 12: Nylon 12 having a relative viscosity of 2.35 was polymerized from 12-7 minododecanoic acid using concentrated sulfuric acid.

Reference Example 3 (Production of modified polyolefin (C)) C-1=
85% by weight of ethylene and 15% by weight of methacrylic acid are copolymerized in the presence of peroxide according to the manufacturing conditions of high-pressure polyethylene, and the resulting copolymer contains 7% of the methacrylic acid.
596 neutralization ionization 1. ,amount. Acetic acid. lead and addition,
Ethylene/methacrylic acid/zinc methacrylate copolymer (ionomer resin) C-1 was produced by uniformly kneading the mixture at 180° C. using a trol mill.

C-2 = Copolymerization of 1% ethylene 79% by weight, 11% by weight isobutyl acrylate, and methacrylic acid according to the manufacturing conditions of high-pressure polyethylene, and 72% of the methacrylic acid contained in the obtained copolymer was carried out. After adding zinc acetate in an amount that can be neutralized and ionized, crosstalk is performed in the same way as in C-1.
Ethylene/isobutyl acrylate/methacrylic acid/zinc methacrylate copolymer (ionomer resin) C-2 was produced.

C-3: 100 parts by weight of an ethylene/propylene copolymer consisting of 70 mol% ethylene and 30 mol% propylene, 0% a,α'-bis-t-butylperoxy-p-diisopropylbenzene dissolved in a small amount of acetone.
．． 03 After adding 1 part M and LO part by weight of maleic anhydride, the ethylene/propylene-g-maleic anhydride copolymer ('g ' represents a graft.>C-3 was produced.

C-4 = 0.1 part by weight of di-t-butyl peroxide dissolved in a small amount of acetone and 10 parts by weight of acrylic acid per 100 parts by weight of an ethylene/propylene copolymer consisting of 80 mol% ethylene and 20 mol% propylene. After adding 50% of the copolymer, ethylene/propylene-g-acrylic acid copolymer C-4 was produced by kneading and pelletizing at 200° C. using an extruder with a diameter of 40 ff in the same manner as C-3.

C-5: Ethylene with a Mooney viscosity of 60 and an iodine value of 12.
Propylene-5-ethylidene-2-norbornene (EP
DM) terpolymer (ethylene/propylene = 68.5
/3L5 (molar ratio)), after adding 0.1 part by weight of di-t-butyl peroxide and 0.5 part by weight of maleic anhydride dissolved in a small amount of acetone,
Similarly to C-3, using an extruder with a diameter of 140Hφ,
EPDM-g-
Maleic anhydride copolymer C-5 was produced.

Example 1 The vinyl copolymer (3) produced in Reference Example, polyamide at, and modified polyolefin C) were mixed in the blending ratio shown in Table 2, melt-kneaded using an extruder with a diameter of 40flφ, and then pelletized. It became. Extrusion temperature is polyamide [3]
250 when using nylon 6 and nylon 12 as
℃, and in the case of using nylon 66, the temperature was 290℃.

Next, this pellet was dried in vacuum, and then a test piece for measuring physical properties was molded by injection molding. During injection molding, the cylinder temperature was set to 260°C when nylon 6 and nylon 12 were used as polyamide 13), and 290°C when nylon 66 was used. The mold temperature was set at 80°C.

The measurement results are shown in Table 2.

Comparative Example Vinyl copolymer N produced in Reference Example, Polyamide 03
), modified polyolefin (C) and the following vinyl copolymer and polyolefin were mixed at the blending ratio shown in Table 2,
Physical properties were measured in the same manner as in Example 1. Table 2 shows the measurement results.
It was shown to.

Vinyl (co)polymer A-6 = Polystyrene A-7: Copolymer consisting of 2% by weight of xy-lenz and 28% by weight of acrylonitrile Polyolefin C-6: 70% by mol of ethylene and 30% by weight of propylene
Ethylene/propylene copolymer C-7 consisting of mol %: A-di-viscous 1f60. Ethylene with an iodine value of 12
Propylene-5-ethylidene-2-norbornene (EP
DM) terpolymer (ethylene/propylene = 68.
5/3 L5 (molar ratio)) From the results of Example 1 and Comparative Example, the following is true. 1,
a. . Yoyo, A01 □ 9, Eng, ~E i[.

11) both have high Izot impact strength and flexural modulus. The Izot impact strength hardly decreases even after 400 hours of irradiation with a Sunshine Weatherometer, and it has excellent weather resistance.

The flexural modulus remains relatively high even after water absorption treatment. That is, the resin composition of the present invention has high impact strength, high rigidity, and excellent weather resistance. On the other hand, the resin composition (f12.13) consisting only of the vinyl copolymer (3) containing no polyamide and modified polyolefin C) has low impact strength. Resin compositions (f14 to f16) consisting only of polyamide CB) containing no vinyl copolymer (A) and modified polyolefin (C) have low flexural modulus.

The flexural modulus is further significantly reduced by water absorption treatment.

Modified polyolefin (vinyl copolymer that does not contain 0)
and polyamitro) (f17.1
8) has low impact strength.

Composition (&19) containing more than 50 parts of modified polyolefin fc) is not preferred because it has a low flexural modulus.

Compositions containing more than 80 parts of polyamide CB+ (4
Nos. 20 and 16) are not preferred because their impact strength is low and their flexural modulus is significantly reduced by water absorption treatment. Resin compositions (&21.22) containing no α, β-unsaturated carboxylic acid (anhydride) in the vinyl copolymer (A) or modified polyolefins (carboxylic acid group, carboxylic acid metal base or acid Resin composition containing no anhydride group (f2
3.24) has low impact strength.

Example 2 Beer-based copolymerizer produced in Reference Example, Pickled Amide CB
), modified polyolefin C1, the vinyl (co)polymer shown in Comparative Example, and polyolefin were mixed at the blending ratio shown in Table 2, and the physical properties were measured in the same manner as in Example 1.

The measurement results are shown in Table 2. In addition to vinyl copolymers (2), polyamitro) and modified polyolefins (C), styrene/acrylonitrile copolymers (2),
co)polymer and ethylene/propylene copolymer rubber (EP
A desirable resin composition having excellent impact strength, flexural modulus, and weather resistance can be obtained by mixing polyolefin rubber such as R).

<Effects of the Invention> As explained above, the resin composition of the present invention is a resin composition that is excellent in both impact resistance represented by impact strength, rigidity represented by flexural modulus, and weather resistance. This effect can only be achieved by blending the vinyl copolymer (3), polyamide IB) and modified polyolefin (C) in the specific proportions of the present invention.

Claims (1)

[Claims] (A), (i) 50 to 99.99% by weight of at least one vinyl monomer selected from the group consisting of aromatic vinyl monomers and (meth)acrylic acid ester monomers;
(b) At least one member selected from the group consisting of α,β-unsaturated carboxylic acids and α,β-unsaturated carboxylic acid anhydrides.
Seed vinyl monomer 0.01-50% by weight and (c)
, a vinyl copolymer obtained by polymerizing 0 to 45% by weight of another vinyl monomer copolymerizable with (a) and/or (b), (B) polyamide and (C) carboxylic acid group, 5 to 90 parts by weight of (A), 1 to 80 parts by weight of (B), and (C) a modified polyolefin having at least one functional group selected from the group consisting of carboxylic acid metal bases and acid anhydride groups; is 5 to 50 parts by weight, and (A), (B)
and (C) in a proportion such that the total amount is 100 parts by weight.