JPH1129702A - Polyamide resin composition and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyamide resin composition excellent in high-impact characteristics, especially in high-impact characteristics at low temperature, rigidity and resistance to water absorption. SOLUTION: This composition is composed of (A) 98-50 wt.%, based on the total weight of components (A), (B) and (C), of a polyamide, (B) 1-40 wt.%, based on the total weight of components (A), (B) and (C), of a modified ethylene/α-olefin copolymer having a melt flow rate(MFR) of 0.05-50 g/10 min (190 deg.C) formed of (B-1) 100 pts.wt. of an ethylene/α-olefin copolymer with a density of less than 0.900 g/cm<3> consisting of 40-93 mol.% of ethylene and 60-7 mol.% of α-olefin having 3 or more carbon atoms, onto which (B-2) 0.01-5 pts.wt. of an unsaturated dicarboxylic acid or a derivative thereof is grafted, and (C) 1-40 wt.%, based on the total weight of components (A), (B) and (C), of at least one ethylene-based copolymer selected from the group consisting of (C-1) a modified ethylene/α-olefin copolymer with Mw/Mn of 2, 5 or less, an MFR of 0.05-50 g/10 min (190 deg.C), an α-olefin content of 10 mol.% or less and a density of 0.970-0.900 g/cm<3> , and (C-2) a modified ethylene/α-olefin copolymer formed of 100 pts.wt. of the ethylene/α-olefin copolymer (C-1) in which 0.01-5 pts.wt. of the unsaturated dicarboxylic acid or a derivative thereof (B-2) is contained, with the weight ratio of the component (B)/component (C) being 20-0.05.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide resin composition excellent in impact resistance, rigidity and water absorption, and a method for producing the same.

[0002]

2. Description of the Related Art Polyamide resins are expected to be in great demand as engineering plastics due to their excellent physical properties. However, impact strength, particularly low-temperature impact resistance, cannot be said to be sufficient, and improvement thereof has been desired. As a method of improving the impact resistance, for example, Japanese Patent Application Laid-Open No. 55-966
No. 1 and Japanese Patent Application Laid-Open No. 55-9662 teach that blending an ethylene / α-olefin copolymer obtained by grafting an α, β-unsaturated carboxylic acid with a polyamide resin improves the Izod impact strength of the polyamide resin. It is described. However, the above composition has a new problem that the rigidity is greatly reduced when the Izod impact strength is improved. Further, the drop weight impact strength at low temperature is insufficient, and there is a problem that the low temperature impact strength of the actual molded product is insufficient.

JP-A-59-78256 describes a polyamide, a modified ethylene / α-olefin copolymer and a polyamide resin composition containing an ethylene polymer, and describes that the impact resistance is improved. ing. However, in this polyamide resin composition, since an ethylene polymer having a large molecular weight distribution (Mw / Mn) is used as the ethylene polymer, improvement in low-temperature impact resistance is insufficient.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyamide resin composition which is excellent in impact resistance, especially low-temperature impact resistance, and which is excellent in rigidity and water absorption. Another object of the present invention is to propose a method for easily and efficiently producing the above polyamide resin composition.

[0005]

Means for Solving the Problems The present inventors have improved the falling weight impact strength and the Izod impact strength at a low temperature so that the rigidity of the polyamide resin is small and the low-temperature impact strength of an actual molded product is satisfied. As a result of repeated studies, the combination of the polymers specified in the present invention has excellent low-temperature impact resistance (drop weight impact strength, Izod impact strength) and rigidity, and salt water resistance due to water absorption. It has been found that a polyamide resin composition having reduced rigidity and little dimensional change can be obtained. Further, they have found that a polyamide resin composition of even higher quality can be obtained by preliminarily melt-mixing these specific polymers and then blending them with a polyamide resin, and reached the present invention.

That is, the present invention relates to the following polyamide resin composition and production method. (1) (A) 98 to 50% by weight of polyamide, (B) (B
-1) 40 to 93 mol% of ethylene content, 60 to 7 mol% of α-olefin having 3 or more carbon atoms, density 0.90
A melt flow rate (MFR (MFR) is obtained by graft-polymerizing 0.01 to 5 parts by weight of an unsaturated dicarboxylic acid (B-2) or a derivative thereof to 100 parts by weight of an ethylene / α-olefin copolymer of less than 0 g / cm ^3. 190 ° C)) 0.05-
1 to 40% by weight of a modified ethylene / α-olefin copolymer of 50 g / 10 min, (C) (C-1) weight average molecular weight / number average molecular weight (Mw / Mn) 2.5 or less, melt flow rate ( MFR (190 ° C.) 0.05-50
g / 10 min, content of α-olefin having 3 or more carbon atoms 10
Mole% or less, an ethylene / α-olefin copolymer having a density of 0.970 to 0.900 g / cm ³ , and (C-2)
The ethylene / α-olefin copolymer (C-1) 10
0 parts by weight of an unsaturated dicarboxylic acid or a derivative thereof (B
-2) 1 to 40% by weight of at least one ethylenic copolymer selected from the group consisting of a modified ethylene / α-olefin copolymer obtained by graft polymerization of 0.01 to 5 parts by weight (where (A ), And the ratio of component (B) to component (C) is the weight of component (B) / component (C). A polyamide resin composition having a ratio of 20 to 0.05. (2) The polyamide resin composition according to the above (1), wherein the density of the ethylene / α-olefin copolymer (B-1) is 0.850 to 0.890 g / cm ³ . (3) The polyamide resin composition according to the above (1) or (2), wherein the ethylene / α-olefin copolymer (C-1) is a polymer polymerized in the presence of a metallocene catalyst. (4) The above (1) or (2), wherein the ethylene / α-olefin copolymer (C-1) is a linear low density polyethylene (LLDPE) polymerized in the presence of a metallocene catalyst.
The polyamide resin composition according to the above. (5) The polyamide resin composition according to any one of the above (1) to (4), wherein the ethylene / α-olefin copolymer (C-1) has a density of 0.940 to 0.900 g / cm ³ . (6) (B) (B-1) Ethylene / α-olefin having an ethylene content of 40 to 93 mol%, a C3 or more α-olefin content of 60 to 7 mol%, and a density of less than 0.900 g / cm ³ A melt flow rate (MFR (190) is obtained by graft-polymerizing 0.01 to 5 parts by weight of (B-2) an unsaturated dicarboxylic acid or a derivative thereof to 100 parts by weight of a copolymer.
℃)) 0.05-50 g / 10 minutes of modified ethylene α-
1 to 40 parts by weight of the olefin copolymer, and (C) (C-
1) weight average molecular weight / number average molecular weight (Mw / Mn)
5 or less, melt flow rate (MFR (190 ° C))
0.05 to 50 g / 10 min, content of α-olefin having 3 or more carbon atoms 10 mol% or less, density 0.970 to 0.90
0 g / cm ^{3 of} an ethylene / α-olefin copolymer and (C-2) 100 parts by weight of the ethylene / α-olefin copolymer (C-1) were added with an unsaturated dicarboxylic acid or a derivative thereof (B-2). And (B) a component (B) with at least one kind of ethylenic copolymer selected from the group consisting of a modified ethylene / α-olefin copolymer obtained by graft-polymerizing 0.01 to 5 parts by weight; Preliminarily melt-mixing in a range of 20 to 0.05 in weight ratio of the / (C) component,
A polyamide resin composition in which this premix is melt-mixed with (A) 98 to 50 parts by weight of a polyamide (however, the total of components (A), (B) and (C) is 100 parts by weight) Manufacturing method. (7) The production method according to the above (6), wherein the ethylene / α-olefin copolymer (C-1) is a polymer obtained by polymerization in the presence of a metallocene catalyst. (8) The production method according to the above (6), wherein the ethylene / α-olefin copolymer (C-1) is a linear low density polyethylene (LLDPE) polymerized in the presence of a metallocene catalyst.

The polyamide (A) used in the present invention is a polymer having an amide bond (-NHCO-) in the main chain, and known polyamides well-known in the present art can be used without limitation. . These are of sufficient molecular weight to produce a molded article. The polyamide (A) can be produced, for example, by condensing a saturated organic dicarboxylic acid containing 4 to 12 carbon atoms with an organic diamine containing 2 to 13 carbon atoms. In this case, it is preferable to use the organic diamine so that the amine end group becomes excess in the polyamide (A) over the carboxyl end group. Conversely, dicarboxylic acids can be used so that the acid groups are in excess.

[0008] Typical dicarboxylic acids used for producing the polyamide (A) include adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and dodecanedicarboxylic acid. In addition, their derivatives, for example, esters, acid chlorides or amine salts can also be used. These can be used alone or in combination of two or more.

On the other hand, representative diamines include hexamethylenediamine, octamethylenediamine, and derivatives thereof. These can be used alone or in combination of two or more. The polyamide (A) can be produced by ring-opening polymerization of a lactam in addition to polycondensation of a dicarboxylic acid and a diamine.

The polyamide (A) produced by polycondensation of a dicarboxylic acid and a diamine includes polyhexamethylene adipamide (nylon 66), polyhexamethylene azelamide (nylon 69), and polyhexamethylene sebasamide. (Nylon 610), polyhexamethylene dodecanoamide (nylon 612), polybis (4-aminocyclohexyl) methane dodecanoamide and the like. Examples of the polyamide (A) produced by ring-opening polymerization of lactams include polycaprolactam (nylon 6) and polylauric lactam.

The polyamide (A) can be used alone or in combination of two or more. Preferable polyamide (A) used in the present invention includes polyhexamethylene adipamide (nylon 66) or a mixture of polyhexamethylene adipamide (nylon 66) and polycaprolactam (nylon 6). .

The modified ethylene / α-olefin copolymer (B) used in the present invention is obtained by adding a specific amount of unsaturated dicarboxylic acid or its derivative (B-2) to the ethylene / α-olefin copolymer (B-1). ) Is a modified ethylene / α-olefin copolymer obtained by graft-copolymerizing a graft monomer selected from the group consisting of:

The ethylene / α-olefin copolymer (B-1) before modification has an ethylene content of 40 to 93 mol%,
Preferably it is 60 to 85 mol%, more preferably 75 to 85 mol%.
85 mol%, the content of α-olefin having 3 or more carbon atoms is 6
It is 0 to 7 mol%, preferably 40 to 15 mol%, and more preferably 25 to 15 mol%. Even if the ethylene content of the ethylene / α-olefin copolymer (B-1) is larger than 93 mol% or smaller than 40 mol%, the ethylene / α-olefin copolymer (B-1) Even if the polyamide (A) is blended with the ethylenic copolymer (C) described below and blended with a graft-modified product of the copolymer (B-1) with the polyamide (A), the impact resistance of the polyamide resin composition becomes high. The improvement effect is not sufficient.

The ethylene / α-olefin copolymer (B-1) has a density of less than 0.900 g / cm ³ , preferably 0.850 to 0.890 g / cm ³ . When the α-olefin is propylene, the density is 0.85
It is particularly preferably 0 to 0.870 g / cm ³ ,
When the α-olefin has 4 to 18 carbon atoms, the density is particularly preferably 0.850 to 0.875 g / cm ³ .

The ethylene / α-olefin copolymer (B-1) has a melt flow rate at 190 ° C. [MFR, a value measured at 190 ° C. under a load of 2160 g (A).
STMD 1238E)) 0.05 to 50
g / 10 minutes, preferably 0.1 to 20 g / 10 minutes. Even if the MFR of the ethylene / α-olefin copolymer (B-1) is smaller than 0.05 g / 10 min or larger than 50 g / 10 min, the copolymer (B
The difference in melt viscosity between the graft-modified ethylene / α-olefin copolymer (B) obtained from -1) and the polyamide (A) tends to be large, and the graft-modified product (B) is added to the polyamide (A). The dispersing effect is not always sufficient, and the effect of improving the impact resistance tends to decrease even when combined with the ethylenic copolymer (C) described below. Further, the ethylene / α-olefin copolymer (B-1) is preferably a low crystalline or non-crystalline one, and its crystallinity is usually 0 to 50%, preferably 0 to 20%. desirable.

The ethylene / α-olefin copolymer (B-
Examples of the α-olefin component unit constituting 1) include α-olefins having 3 or more carbon atoms, preferably about 3 to 18 carbon atoms, such as propylene, 1-butene, 1-hexene,
Examples thereof include -methyl-1-pentene, 1-octene, 1-decene and the like. These can be used alone or as a mixture of two or more.

The ethylene / α-olefin copolymer (B-
1) is usually a copolymer of an ethylene component and an α-olefin component, but in some cases, it may contain a trace amount, for example, a diene component in a range of 0.5 mol% or less. If the content of the diene component exceeds 0.5 mol%, mixing with the ethylenic copolymer (C) becomes poor due to crosslinking, and dispersion in the polyamide (A) becomes poor.

The ethylene / α-olefin copolymer (B-
1) can be produced by a method using a Ziegler-Natta catalyst or a metallocene catalyst, or other known methods such as an ICI method, a BASF method, a Phillips method, and a standard method.

The unsaturated dicarboxylic acid (B-2) used as the graft monomer includes maleic acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid,
And unsaturated dicarboxylic acids such as isocrotonic acid and nadic acid (endosis-bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid). These derivatives (B-2) include, for example, acid halides, amides, imides, anhydrides, esters and the like. Specific examples include maleenyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, and maleate. Examples thereof include dimethyl acid and glycidyl maleate. Of these, anhydrides are preferred, and maleic anhydride and nadic anhydride are particularly preferred. These can be used alone or in combination of two or more.

The graft ratio of the unsaturated dicarboxylic acid or its derivative (B-2) of the modified ethylene / α-olefin copolymer (B) used in the present invention is ethylene / α-olefin.
It is 0.01 to 5 parts by weight, preferably 0.1 to 4 parts by weight, based on 100 parts by weight of the olefin copolymer (B-1). If the graft ratio of the graft monomer is less than 0.01 parts by weight, the compatibility with the polyamide (A) is deteriorated, delamination occurs, and the effect of improving impact resistance is reduced. On the other hand, when the graft ratio is more than 5 parts by weight, the degree of crosslinking of the graft-modified product (B) increases, and even when blended with the polyamide (A), the effect of improving the impact resistance decreases.

The graft-modified ethylene / α-olefin copolymer (B) has a melt flow rate (MFR, 2,160 g under load, measured at 190 ° C.) of 0.05-5.
0 g / 10 min, preferably 0.1 to 20 g / 10 min.

The density of the graft-modified ethylene / α-olefin copolymer (B) is usually less than 0.902 g / cm ³ ,
Preferably, it is 0.852 to 0.892 g / cm ³ . When the α-olefin is propylene, the density is particularly preferably 0.852 to 0.872 g / cm ^{3. When} the α-olefin has 4 to 18 carbon atoms, the density is 0.852 to 0. .877g / c
m ³ is particularly preferred.

The unsaturated dicarboxylic acid or a derivative thereof (B
-2) is a graft monomer selected from ethylene α-
For graft copolymerization to the olefin copolymer (B-1), various conventionally known methods can be employed. For example, there is a method in which the ethylene / α-olefin copolymer (B-1) is melted or dissolved in a solvent, and a graft monomer is added to carry out graft polymerization. At the time of graft polymerization, another vinyl monomer such as styrene may be allowed to coexist. In particular, the modified ethylene / α-olefin copolymer (B) obtained by efficiently performing graft polymerization using a radical generator is obtained by oxidizing the ethylene / α-olefin copolymer (B-1) as a raw material. , And is preferably used in the present invention.

Examples of the radical generator include organic peroxides, organic peresters and azo compounds. Specific examples include, for example, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide,
5-dimethyl-2,5-di (peroxybenzoate)
Hexin-3,1,4-bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butylperacetate, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3,2 5-dimethyl-2,5-di (tert-butylperoxy) hexane, tert-butylperbenzoate, tert-butylperphenylacetate,
tert-butyl perisobutyrate, tert-butyl per-sec-octoate, tert-butyl perpivalate, cumyl perpivalate, tert-butyl perdiethyl acetate, azobisisobutyronitrile, dimethylazoisobutyrate and the like. can give. Among these, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (t
Dialkyl peroxides such as tert-butylperoxy) hexine-3, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, and 1,4-bis (tert-butylperoxyisopropyl) benzene are preferred.

The modified ethylene / α-olefin copolymer (B) can be used alone or in combination of two or more.

The ethylenic copolymer (C) used in the present invention has a (C-1) weight average molecular weight / number average molecular weight (Mw / Mn) of 2.5 or less, preferably 1.5 to 2.
3, melt flow rate (MFR (190 ° C.)) 0.0
5 to 50 g / 10 min, preferably 0.1 to 20 g / 10
, The content of α-olefin having 3 or more carbon atoms, preferably 3 to 18 is 10 mol% or less, preferably 3 to 10 mol%, and the density is 0.970 to 0.900 g / cm ³ ,
An ethylene / α-olefin copolymer having preferably 0.940 to 0.900 g / cm ³ , and (C-2) the ethylene / α-olefin copolymer (C-1) 100
Parts by weight of an unsaturated dicarboxylic acid or a derivative thereof (B-
2) at least one ethylenic copolymer selected from the group consisting of a modified ethylene / α-olefin copolymer obtained by graft polymerization of 0.01 to 5 parts by weight, preferably 0.1 to 4 parts by weight; is there. The melt flow rate (MFR (190 ° C.)) was 190 ° C. under a load of 2160 g.
At 190 ° C. (method according to ASTM D 1238E).

The ethylene / α-olefin copolymer (C-
Examples of the α-olefin copolymerized with ethylene in 1) include propylene, 1-butene, and 3-methyl-1
-Butene, 1-pentene, 1-hexene, 4-methyl-
1-pentene and the like.

The ethylene / α-olefin copolymer (C-1) has a crystallinity of 90 to 20%, preferably about 7%.
Desirably, it is 0 to about 30%. Also ethylene ・ α-
As the olefin copolymer (C-1), linear low-density polyethylene (LLDPE) is particularly preferred. The density of the modified ethylene / α-olefin copolymer (C-2) is usually from 0.972 to 0.902 g / cm ³ , preferably from 0.972 to 0.902 g / cm ³ .
It is desirably 42 to 0.902 g / cm ³ .

The ethylenic copolymer (C) is preferably an ethylene / α-olefin copolymer (C-1), particularly preferably a linear low density polyethylene (LLDPE).
The ethylenic copolymer (C) can be used alone or in combination of two or more.

The ethylene / α-olefin copolymer (C-1) used as the ethylenic copolymer (C) or the ethylene / α-olefin copolymer used in the modified ethylene / α-olefin copolymer (C-2) As the polymer (C-1), those polymerized in the presence of a metallocene catalyst are preferable. When a metallocene-based catalyst is used, a polyethylene having a narrow molecular weight distribution can be produced. Therefore, an ethylene / α-olefin copolymer (C-1) having a narrow molecular weight distribution of Mw / Mn of 2.5 or less used in the present invention. Can also be easily manufactured.

The ethylene / α-olefin copolymer (C-
As the metallocene-based catalyst as a single-site catalyst suitably used in the production of 1), a conventionally known metallocene-based catalyst can be used without limitation, and for example, a metallocene having a transition metal such as titanium, zirconium, or hafnium can be used. Examples include a catalyst comprising the compound (d) and the organic aluminum oxy compound (e), and a catalyst comprising the metallocene compound (d) and the ionized ionic compound (f).

Specific examples of the metallocene compound (d) include a transition metal compound represented by the following formula (1). MLx (1) In the formula (1), M is a transition metal atom selected from Group IVB of the periodic table, specifically, zirconium, titanium or hafnium, and x is the valence of the transition metal.

In the formula (1), L is a ligand which coordinates to the transition metal, and at least one of the ligands L is a ligand having a cyclopentadienyl skeleton. The ligand having a pentadienyl skeleton may have a substituent. Examples of the ligand having a cyclopentadienyl skeleton include a cyclopentadienyl group; a methylcyclopentadienyl group, an ethylcyclopentadienyl group, a methylpropylcyclopentadienyl group, a methylbutylcyclopentadienyl group, Alkyl or cycloalkyl-substituted cyclopentadienyl groups such as methylhexylcyclopentadienyl group, methylbenzylcyclopentadienyl group, ethylbutylcyclopentadienyl group, ethylhexylcyclopentadienyl group, methylcyclohexylcyclopentadienyl group, etc. An indenyl group,
4,5,6,7-tetrahydroindenyl group, fluorenyl group and the like. These groups may be substituted with a halogen atom, a trialkylsilyl group or the like.

When the compound represented by the formula (1) has two or more groups having a cyclopentadienyl skeleton as the ligand L, two of the groups having the cyclopentadienyl skeleton may be substituted by ethylene. And a substituted alkylene group such as isopropylidene or diphenylmethylene; a silylene group; preferably bonded via a substituted silylene group such as a dimethylsilylene group, a diphenylsilylene group or a methylphenylsilylene group.

L other than a ligand having a cyclopentadienyl skeleton is a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group, an aryloxy group, a sulfonic acid-containing group (-SO
₃ R ¹ ), a halogen atom or a hydrogen atom (here, R ¹ is an alkyl group, an alkyl group substituted with a halogen atom, an aryl group, or an aryl group substituted with a halogen atom or an alkyl group). Can be

The metallocene compound (d) represented by the formula (1) is more specifically represented by the following formula (2) when the valence of the transition metal is 4, for example. ^{R 2 pR 3 qR 4 rR 5} sM ... (2) formula (2), M is the same transition metal as the formula (1), R ²
Is a group (ligand) having a cyclopentadienyl skeleton, and R ³ , R ⁴ and R ⁵ are each independently a group having a cyclopentadienyl skeleton or a cyclopentadienyl skeleton in the formula (1). And the same as L except for a ligand having p is an integer of 1 or more, and p + q + r + s = 4.

Examples of the organoaluminum oxy compound (e) used together with the metallocene compound (d) include aluminoxanes such as methylaluminoxane.

The ionized ionic compound (f) used together with the metallocene compound (d) includes a Lewis acid,
Examples thereof include ionic compounds, borane compounds, and carborane compounds. As the Lewis acid,
BR ₃ (R is a phenyl group or a fluorine which may have a substituent such as a fluorine, a methyl group, a trifluoromethyl group, etc.), and the like, for example, trifluoroboron, triphenyl Boron, Tris (4
-Fluorophenyl) boron, tris (3,5-difluorophenyl) boron, tris (4-fluoromethylphenyl) boron, tris (pentafluorophenyl) boron, tris (p-tolyl) boron, tris (o-tolyl) boron And tris (3,5-dimethylphenyl) boron.

Examples of the above ionic compounds include trialkyl-substituted ammonium salts, N, N-dialkylanilinium salts, dialkylammonium salts, triarylphosphonium salts, triphenylcarbenium tetrakis (pentafluorophenyl) borate, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, ferrocenium tetra (pentafluorophenyl) borate and the like can be mentioned. Examples of the borane compound include decaborane (14), bis [tri (n-
Butyl) ammonium] nonaborate and the like. The metallocene catalyst can be used in combination with an organoaluminum compound.

The mixing ratio of each component of the resin composition of the present invention is 98 to 50% by weight of polyamide (A), preferably 9% by weight.
6 to 60% by weight, modified ethylene / α-olefin copolymer (B) 1 to 40% by weight, preferably 3 to 30% by weight,
1 to 40% by weight, preferably 3 to 30% by weight of the ethylenic copolymer (C) (however, it is a percentage by weight based on the total amount of the components (A), (B) and (C)) And the ratio of component (B) to component (C) is (B) component /
(C) 20 to 0.05, preferably 10 in weight ratio of the component.
~ 0.1.

When the proportion of each component does not satisfy the above conditions, the effect of improving the impact properties is insufficient. Particularly, when the component (B) or (C) is added in a large amount, the excellent rigidity of the polyamide (A) is deteriorated, which is not preferable.

In the resin composition of the present invention, in addition to the essential components (A) to (C), additives conventionally blended in polyamides, polyolefin resins or modified polyolefin resins, etc. More than one kind can be blended. Such other components include, for example, phenol or amine antioxidants, ultraviolet absorbers, light protectants, metal deactivators, phosphite stabilizers, peroxide decomposers, polyamide stabilizers, bases And the like. Sex auxiliary stabilizers, polyvinyl chloride stabilizers, nucleating agents, plasticizers, lubricants, emulsifiers, antistatic agents, flame protectants, pigments, carbon black, asbestos, glass fibers, kaolin or talc. Accordingly, the resin compositions of the present invention include multi-component resin compositions containing one or more additives together with the essential components. Examples of suitable said additives are selected from the following group: In particular, the antioxidants exemplified below, and the resin composition of the present invention containing the antioxidants exemplified below and an ultraviolet absorber provide extremely effective stability.

These additives are described, for example, in JP-A-50-11
No. 1140 (corresponding U.S. Pat. No. 3,975,357), and as an antioxidant, a 2,6-dialkylphenol such as 2,6-di-tert-butyl-4-methylphenol; an alkylated hydroquinone derivative For example, 2,5-di-tert-butyl-hydroquinone; hydroxylated thiodiphenyl ethers, for example 2,2-thiobis- (6-tert-butyl-4-methylphenol); alkylidene-bisphenols, for example 2,2'-methylene -Bis (6-tert-butyl-
4-methylphenol); O-, N- and S-benzyl compounds such as 3,5,3 ', 5'-tetra-ter
tert-butyl-4,4'-dihydroxybenzyl ether, 4-hydroxy-3,5-dimethylbenzyl-mercaptoacetic acid octadecyl ester; hydroxybenzylated malonic ester such as 2,2-bis (3,5-di-tert. -Butyl-2-hydroxybenzyl) -malonic acid dioctadecyl ester, 2- (3-tert-butyl-4-hydroxy-5-methylbenzyl) -malonic acid dioctadecyl ester; hydroxybenzyl-aromatic hydrocarbon, e.g. , 3,5-tri (3,5-di-t
tert-butyl-4-hydroxybenzyl) -2,4.
6-trimethylbenzene; s-triazine compound such as 2,4-bisoctylmercapto-6- (3,5-di-tert-butyl-4-hydroxyanilino) -s-
Triazines; amides of 3,5-di-tert-butyl-4-hydroxyphenyl-propionic acid, such as 1,1
3,5-tri (3,5-di-tert-butyl-4-hydroxyphenyl-propionyl) -hexahydro-s
Esters of 3,5-di-tert-butyl-4-hydroxyphenyl-propionic acid with monohydric or polyhydric alcohols, such as methanol, ethanol, octadecanol, 1,
6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, diethylene glycol, thiodiethylene glycol, neopentyl glycol, pentaerythritol, trimethylolpropane; 5-tert-butyl-4-hydroxy-3
Esters of methylphenylpropionic acid with monohydric or polyhydric alcohols, such as methanol, ethanol, octadecanol, 1,6
-Hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, diethylene glycol, thiodiethylene glycol, neopentyl glycol, pentaerythritol, trimethylolpropane; 3,5-di-tert-butyl-4-hydroxy Esters of phenylacetic acid with monohydric or polyhydric alcohols, such as methanol,
Ethanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,
1,2-propanediol, diethylene glycol, thiodiethylene glycol, neopentyl glycol, pentaerythritol, trimethylolpropane; aminoaryl derivatives such as phenyl-1-naphthylamine and phenyl-2-naphthylamine.

As the ultraviolet absorber or photoprotective agent, a derivative of 2- (2-hydroxyphenyl) -benztriazole; 2,4-bis (2'-hydroxyphenyl)
Derivatives of -6-alkyl-s-triazines; 2-hydroxy-benzophenone derivatives; 1,3-bis (2'-hydroxy-benzoyl) -benzene; esters of substituted benzoic acids, such as phenyl salicylate;
For example, α-cyano-β, β-diphenylacrylic acid ethyl ester or isooctyl ester; nickel compounds such as 2,2′-thiobis- (4-tert-octylphenol) and nickel complexes 1: 1 and 1: 2
Complexes, such as nickel dibutyl dithiocarbamate,
2-hydroxy-4-methyl-phenyl-undecyl-
Nickel complexes of ketone oximes; oxalic acid diamides such as 4,4'-dioctyloxyoxanilide.

Examples of the metal deactivator include oxanilide and the like; examples of the phosphite stabilizer include triphenyl phosphite and the like; examples of the peroxide decomposing agent include salts of 2-mercaptobenzimidazole; For example, zinc salt, diphenylthiourea and the like; as a polyamide stabilizer, for example, a copper salt bonded to an iodine and / or phosphorus compound; and as a basic co-stabilizer,
For example, polyvinylpyrrolidone, polyurethane and the like, as well as alkali metal salts and alkaline earth metal salts of higher saturated or unsaturated fatty acids, such as calcium stearate; polyvinyl chloride stabilizers such as organotin compounds;
Barium or cadmium salts of fatty acids; nucleating agents include, for example, 4-tert-butylbenzoic acid;

The amount of these additives to be added to the resin composition of the present invention can be varied within a wide range. In the present invention, it is desirable to use an antioxidant, particularly a phenolic antioxidant, and the compounding amount thereof is preferably about 0.01 to about 3% by weight based on the entire polyamide resin composition.

The resin composition of the present invention is prepared by melt-mixing by various methods. For example, there is a method in which arbitrary two components are pre-mixed and then mixed with the remaining other components, or three components are simultaneously mixed. At any of these stages, an additional amount of an additive, for example, an antioxidant can be added as necessary.

The resin composition of the present invention comprises the component (B) and the component (C)
Preferably, the components are preliminarily melt-mixed, and the pre-mixture is melt-mixed with the polyamide (A) component. In this case, the components (B) and (C) are preliminarily melt-mixed in a range of 20 to 0.05, preferably 10 to 0.1 by weight of the component (B) / component (C). Then, the premix and 98 to 50 parts by weight, preferably 96 to 60 parts by weight of polyamide (A) (provided that component (A) and component (B)
And the total of the components (C) and (C) is 100 parts by weight). The polyamide resin composition thus produced is particularly excellent in various properties such as impact resistance, rigidity and water absorption.

More preferably, when preparing the premix, it is desirable to mix it with an antioxidant. As the antioxidant to be added when preparing the premix, a phenolic antioxidant is particularly suitable, and is used in an amount of about 0.01 to about 3 parts by weight, preferably about 0.02 parts by weight, per 100 parts by weight of the premix. Desirably, about 0.5 parts by weight.

The resin composition of the present invention maintains high rigidity and has improved properties such as impact resistance, especially low-temperature impact resistance, moisture absorption resistance and salt water strength. The resin composition of the present invention is formed into various shapes by various conventionally known melt molding methods. For example, there are methods such as injection molding, extrusion molding, compression molding, foam molding and the like, which are used for a wide range of applications including automobile parts, electric appliances and electric parts.

[0051]

As described above, the polyamide resin composition of the present invention comprises a polyamide (A) and a specific modified ethylene / α
-Since it contains the olefin copolymer (B) and the specific ethylenic copolymer (C) in specific amounts, it is excellent in impact resistance, particularly low-temperature impact resistance, rigidity and water absorption resistance. In the method for producing a polyamide resin composition of the present invention, after the modified ethylene / α-olefin copolymer (B) and the ethylenic copolymer (C) are melt-mixed, the premix and the polyamide (A) are mixed. Since the melt mixing is performed, a polyamide resin composition having excellent impact resistance, particularly low-temperature impact resistance, rigidity and water absorption resistance, can be easily and efficiently produced.

[0052]

Next, an embodiment of the present invention will be described. Production Example 1 << Production of Ethylene / α-Olefin Copolymer Used as Component (C) >> [Preparation of Metallocene Catalyst] 10.0 kg of silica dried at 250 ° C. for 10 hours was suspended in 154 liter toluene. Then, it was cooled to 0 ° C. Thereafter, a toluene solution of methylaluminoxane (Al = 1.33 mol / li)
ter) 57.5 liter was added dropwise over 1 hour. At this time, the temperature in the system was kept at 0 ° C. Subsequently, the reaction was carried out at 0 ° C. for 30 minutes, then the temperature was raised to 95 ° C. over 1.5 hours, and the reaction was carried out at that temperature for 20 hours. Thereafter, the temperature was lowered to 60 ° C., and the supernatant was removed by a decantation method. The solid component thus obtained was washed twice with toluene and then resuspended in 100 liter of toluene. Bis (1-methyl-3-n-butylcyclopentadienyl)
A toluene solution of zirconium dichloride (Zr = 27.
(0 mmol / liter) 16.8 liter was added dropwise at 80 ° C. over 30 minutes, and further reacted at 80 ° C. for 2 hours. Thereafter, the supernatant was removed and washed twice with hexane to obtain a metallocene-based solid catalyst containing 3.5 mg of zirconium per gram.

[Preparation of Prepolymerized Catalyst] In 87 liters of hexane containing 2.5 mol of triisobutylaluminum, 870 g of the metallocene-based solid catalyst obtained above was added.
Then, 260 g of 1-hexene was added thereto, and prepolymerization of ethylene was performed at 35 ° C. for 5 hours to obtain a prepolymerized catalyst in which 10 g of polyethylene was prepolymerized per 1 g of the solid catalyst.

[Polymerization] Using a continuous fluidized-bed gas-phase polymerization apparatus, ethylene and 1-hexene were copolymerized at a total pressure of 2.0 MPa (20 kgf / cm ² , gauge pressure) and a polymerization temperature of 70 ° C. The prepolymerized catalyst prepared above was continuously supplied at a rate of 0.03 mmol / h in terms of zirconium atoms, and triisobutylaluminum at a rate of 5.0 mmol / h, and ethylene was added to maintain a constant gas composition during the polymerization. , 1-hexene, hydrogen, and nitrogen were continuously supplied (gas composition (molar ratio); 1-hexene / ethylene =
0.035, hydrogen / ethylene = 4.5 × 10 ⁻⁴ , ethylene concentration = 70 mol%).

The yield of the obtained ethylene / α-olefin copolymer (LLDPE) was 6.0 kg / h, the density was 0.905 g / cm ³ , and the MFR was 4.0 g / h.
10 minutes, Mw / Mn was 2.2, the temperature at the maximum peak position of the endothermic curve measured by a differential scanning calorimeter (DSC) was 106.8 ° C., and the content of decane-soluble components at 23 ° C. 0.22% by weight, the number of unsaturated bonds is 0.09 per 1,000 carbon atoms, and the polymer 1
There were 0.70 per molecule.

Production Example 2 << Production of Ethylene / α-Olefin Copolymer Used in Comparative Example >> [Preparation of Catalyst Component] Under nitrogen atmosphere, 1 mol of anhydrous magnesium chloride (commercially available) was suspended in 2 liters of dehydrated and purified hexane. The mixture was turbidized, and 6 mol of ethanol was added dropwise with stirring over 1 hour, followed by a reaction at room temperature for 1 hour. After the reaction, 2.6 mol of diethyl aluminum chloride was added dropwise thereto at room temperature, and stirring was continued for 2 hours. Next, 6 mol of titanium tetrachloride was further added, and then the system was heated to 80 ° C. and reacted while stirring for 3 hours. After the reaction, the obtained solid was separated and washed repeatedly with purified hexane. When the composition of this solid (hereinafter referred to as α-1) was examined, the composition was as follows. Ti: 3.6 wt% Cl: 66.8 wt% Mg: 20.0 wt% Al: 0.4 wt% OC ₂ H _5: 4.7 wt% In addition the OC ₂ H _5, the resulting solid after decomposing extraction with H ₂ O-acetone and quantified as ethanol by gas chromatography.

Then, 500 mmol of ethanol was added at room temperature to 50 mmol of α-1 in terms of Ti suspended in purified hexane, and the temperature was raised to 50 ° C. and reacted for 1.5 hours. . After the reaction, the obtained solid portion was repeatedly washed with purified hexane. The composition of the catalyst thus obtained (hereinafter referred to as β-1) was as follows. Ti: 1.2 wt% Cl: 52.8 wt% Mg: 15.9 wt% Al: 0.7 wt% OC ₂ H _5: 22.7 wt% The above OC ₂ H ₅ is determined in the same manner as the Was.

[Polymerization] Using a continuous reactor having an internal volume of 200 liter, dehydrated and purified hexane was obtained at 85 liter / hr, diethylaluminum chloride at 6 mmol / hr, and ethylaluminum sesquichloride at 6 mmol / hr. The converted catalyst (β-1) was converted to Ti to obtain a value of 0.1.
It is continuously supplied at a rate of 42 mmol / hr, and 13 kg / hr of ethylene and 9 kg / h of 1-butene are used as raw materials.
r and hydrogen were continuously supplied into the polymerization reactor at a rate of 8.0 liter / hr, and the polymerization temperature was 170 ° C. and the total pressure was 3.1 MPa (3 MPa).
0 kgf / cm ² , gauge pressure), average residence time 1.3 hours, copolymer concentration with respect to hexane 130 g / l
The copolymerization reaction was performed under the following conditions. The catalytic activity is 221
00g-copolymer / mmol-Ti.

Example 1 Nylon 6 (trade name, CM1017, manufactured by Toray Industries, Inc.)
Ethylene / 1-butene copolymer [ethylene content = 81
Mol%, MFR = 0.5 g / 10 min, density = 0.860
g / cm ³ , crystallinity = 0%] Maleic anhydride graft-modified ethylene / 1-butene copolymer obtained by graft copolymerizing 100 parts by weight of maleic anhydride with 1.0 part by weight [MFR
(190 ° C.) = 1.5 g / 10 min] and the polyethylene of Production Example 1 (ethylene content = 94.3 mol%, MFR
(190 ° C.) = 4.0 g / 10 min, density = 0.905 g
/ Cm ³ , Mw / Mn = 2.2) at a ratio shown in Table 1 using a blender to prepare a dry blended product.

The dry blended resin composition was treated with L / D =
40, 30mmφ twin screw extruder, 245 ℃, 50
The mixture was kneaded by passing once at rpm and granulated. After drying the granulated pellet sample at 80 ° C. for 24 hours, a physical property test piece was prepared using an M50AII-DM injection molding machine manufactured by Nippon Steel Works under the following conditions. Cylinder temperature: 245 ° C Injection pressure: 61 MPa (600 kgf / cm ² ) Mold temperature: 80 ° C

Subsequently, physical properties were evaluated by the following methods. Table 2 shows the results. << Bending test >> Using a 1/8 inch thick test piece, AST
The bending elastic modulus and the bending yield point stress were measured according to MD-790-80. << Tensile test >> Using a 1/8 inch thick test piece, AS
The yield stress, the stress at break, and the elongation at break were measured by TM D638. << Izod impact strength >> According to ASTM D256, using a 1/8 inch thick test piece, 23 ° C, -20 ° C,-
The notched Izod impact strength was measured at 40 ° C.

Example 2 Ethylene copolymer (C) shown in Table 1
Example 1 was repeated except that a 1-hexene copolymer was used. Table 2 shows the results.

Example 3 In Example 1, instead of the maleic anhydride-grafted ethylene / 1-butene copolymer as the component (B),
Example 1 was repeated except that a maleic anhydride graft-modified ethylene / 1-octene copolymer [MFR (190 ° C) = 0.6 g / 10 min] was used. Table 2 shows the results.

Comparative Example 1 The physical properties were measured in the same manner as in Example 1 except that the polyamide (A) was used alone. Table 2 shows the results.

Comparative Example 2 In Example 1, the ethylene / α-olefin copolymer of Production Example 2 was replaced with the ethylene / α-olefin copolymer (C) of Production Example 1.
Example 1 was repeated except that an olefin copolymer was used. Table 2 shows the results.

Comparative Examples 3 and 4 Using the resin compositions shown in Table 1, physical properties were measured in the same manner as in Example 1. Table 2 shows the results.

[0067]

[Table 1]

[0068]

[Table 2]

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[Procedure amendment]

[Submission date] July 17, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0067

[Correction method] Change

[Correction contents]

[0067]

[Table 1]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 23:26)

Claims (8)

[Claims] 1. (A) 98 to 50% by weight of polyamide; (B) (B-1) 40 to 93% by mole of ethylene, 60 to 7% by mole of α-olefin having 3 or more carbon atoms, and 0 density. (B-2) Unsaturated dicarboxylic acid or a derivative thereof is added to 100 parts by weight of an ethylene / α-olefin copolymer of less than 900 g / cm ^3.
A melt flow rate (MFR (190 ° C.)) obtained by graft polymerization of 1 to 5 parts by weight of 1 to 40% by weight of a modified ethylene / α-olefin copolymer of 0.05 to 50 g / 10 minutes, and (C) ( C-1) Weight average molecular weight / number average molecular weight (Mw
/ Mn) 2.5 or less, melt flow rate (MFR (1
90 [deg.] C.)) 0.05 to 50 g / 10 min, content of [alpha] -olefin having 3 or more carbon atoms 10 mol% or less, density 0.970
To 0.900 g / cm ^{3 of} an ethylene / α-olefin copolymer and (C-2) 100 parts by weight of the ethylene / α-olefin copolymer (C-1), an unsaturated dicarboxylic acid or a derivative thereof ( B-2) 1 to 40% by weight of at least one ethylenic copolymer selected from the group consisting of a modified ethylene / α-olefin copolymer obtained by graft polymerization of 0.01 to 5 parts by weight (where ( A) component,
(% By weight based on the total amount of the components (B) and (C)), and the ratio of the component (B) to the component (C) is 20 by the weight ratio of the component (B) / the component (C). A polyamide resin composition of from 0.05 to 0.05. 2. An ethylene / α-olefin copolymer (B)
Claim 1 The polyamide resin composition according density of 0.850~0.890g / cm ³ -1). 3. An ethylene / α-olefin copolymer (C)
3. The polyamide resin composition according to claim 1, wherein -1) is a polymer polymerized in the presence of a metallocene catalyst. 4. An ethylene / α-olefin copolymer (C
3. The polyamide resin composition according to claim 1, wherein -1) is linear low density polyethylene (LLDPE) polymerized in the presence of a metallocene catalyst. 5. An ethylene / α-olefin copolymer (C)
Claims 1 Density -1) is 0.940~0.900g / cm ³ to the polyamide resin composition according to any one of 4. 6. (B) (B-1) an ethylene content of 40 to
93 mol%, α-olefin content of 3 or more carbon atoms 60
(B-2) unsaturated dicarboxylic acid or a derivative thereof is added to 100 parts by weight of an ethylene / α-olefin copolymer having a density of less than 0.97 g / cm ^3.
1 to 40 parts by weight of a modified ethylene / α-olefin copolymer having a melt flow rate (MFR (190 ° C.)) of 0.05 to 50 g / 10 minutes obtained by graft polymerization of 1 to 5 parts by weight; C-1) Weight average molecular weight / number average molecular weight (Mw
/ Mn) 2.5 or less, melt flow rate (MFR (1
90 [deg.] C.)) 0.05 to 50 g / 10 min, content of [alpha] -olefin having 3 or more carbon atoms 10 mol% or less, density 0.970
To 0.900 g / cm ^{3 of} an ethylene / α-olefin copolymer and (C-2) 100 parts by weight of the ethylene / α-olefin copolymer (C-1), an unsaturated dicarboxylic acid or a derivative thereof ( B-2) 1 to 40 parts by weight of at least one ethylenic copolymer selected from the group consisting of a modified ethylene / α-olefin copolymer obtained by graft polymerization of 0.01 to 5 parts by weight; Preliminarily melt-mixing the component (B) in a range of 20 to 0.05 in terms of the weight ratio of the component (C) and 98 to 50 parts by weight of (A) polyamide (provided that the component (A) (B) The total amount of the component (B) and the component (C) is 100 parts by weight). 7. An ethylene / α-olefin copolymer (C
The method according to claim 6, wherein -1) is a polymer polymerized in the presence of a metallocene catalyst. 8. An ethylene / α-olefin copolymer (C
The method according to claim 6, wherein -1) is linear low density polyethylene (LLDPE) polymerized in the presence of a metallocene catalyst.