JPS62223251A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which has excellent compatibility, mechanical properties and surface gloss and is lowly water-absorptive and suitable for use in the production of automobile parts, appliance parts, etc., consisting of a specified modified polyolefin, a polyamide, a polyolefin and a lowly crystalline ethylene/alpha-olefin copolymer. CONSTITUTION:100pts. (by weight; the same applies hereinbelow) mixture of 10-95wt% polyolefin (a) (e.g., PP) and 90-5wt% polyamide (b) is blended with 0.001-10pts. unsaturated carboxylic acid (derivative) (c) [e.g., maleic acid (anhydride)] and optionally, 0.001-5pts. org. peroxide (d). The mixture is melt- kneaded to carry out a grafting reaction, thus obtaining a modified polyolefin (A). 5-95pts. component A is blended with 5-95pts. polyamide (B), 0-90pts. polyolefin (C) and 5-80pts. lowly crystalline ethylene/alpha-olefin copolymer (D) having an ethylene content of 30-85wt%, a Mooney viscosity ML1+8(127 deg.C) of 5-300 and a crystallinity index of not higher than 40% in such a proportion that the combined amount of the components A, B, C and D is 100pts. and the combined amount of the polyolefins in the compsn. is 10-90wt%. The mixture is melt-kneaded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to thermoplastic resin compositions, and in particular to co-modified polyolefins and polyamides, polyamides, polyolefins and low crystalline ethylene-α-olefin copolymers. The present invention relates to an impact-resistant composition having excellent compatibility.

Conventional Technology Polypropylene and polyamide can be blended for the purpose of improving the mechanical strength, heat resistance, dyeability, etc. of polypropylene, which is a representative crystalline polyolefin, and the water absorption of polyamide, and the deterioration of physical properties due to water absorption. Are known.

However, compositions obtained by simply melt-kneading polypropylene and polyamide suffer from poor compatibility, resulting in interphase delamination, resulting in decreased surface gloss and mechanical properties, and are unable to provide materials with the desired excellent properties. Table. For this reason, a method has been proposed in which maleic anhydride-modified polypropylene is interposed when blending polypropylene and polyamide.

However, simply adding this modified polypropylene is not sufficient to improve physical properties such as impact resistance and surface properties, and it has been proposed to incorporate a modified product of unsaturated carboxylic acid anhydride into a low-crystalline or non-crystalline polymer. being done. For example, compositions consisting of polyamides and modified mixtures of crystalline polyolefins and low-crystalline or non-crystalline ethylene/α-olefin copolymers (Japanese Unexamined Patent Publication No. 57-8246), modified polypropylenes, polyamides, etc. , a composition comprising a modified ethylene/α-olefin copolymer with low crystallinity or non-quality properties and an inorganic filler (JP-A-60-555)
50), polypropylene, polyamide and/or polyester, low crystallinity or non-quality ethylene-α
- A composition comprising a modified olefin copolymer and an inorganic filler (JP-A-60-76548), polypropylene, polyamide, and a low-crystalline or non-crystalline modified propylene-α-olefin copolymer A composition (Japanese Unexamined Patent Publication No. 110740/1983) has been proposed.

Problems to be Solved by the Invention However, although the impact resistance of conventional compositions has been improved by incorporating low-crystalline or non-crystalline copolymers or acid-modified products thereof, However, the improvement effect was not satisfactory.

The present invention solves the problems of conventional compositions, improves the compatibility of compositions consisting of polyolefin polyamides, modified polyolefins, and low crystalline copolymers, and improves surface properties and mechanical properties, especially resistance. The purpose is to provide a composition with excellent impact resistance.

Means for Solving the Problems The present invention provides a modified polyolefin (A) 5-95 in which a monounsaturated carboxylic acid or a derivative thereof is reacted with a mixture consisting of a polyolefin of 10-95 by weight and a polyamide of 90-5 by weight. Parts by weight, polyamide φ) 5-95 Parts by weight, polyolefin (C) O-90 parts by weight and U (
A) + 03) + (C) = 100 It consists of a low crystalline ethylene-α-olefin copolymer @5 to 80 parts by weight based on 31 parts by weight, and the polyolefin unit in the composition is 10 to 90 parts by weight. The content of the thermoplastic resin composition which is F% by weight is summarized.

The polyolefin in the present invention also includes ethylene 1, <H propylene, butene-1, pentene-1, hexene-1,
These are crystalline polymers such as homopolymers of α-olefins such as 4-methylpentene-1, copolymers of ethylene and α-olefins, or copolymers of two or more of these α-olefins. The copolymer herein includes random or block copolymers. Moreover, two or more types of these resins can be used in combination.

Among the above-mentioned polyolefins, polymers mainly composed of propylene are preferred, such as polypropylene and random or block copolymers obtained by copolymerizing propylene with ethylene or other α-olefins.

The polyamide used in the modified polyolefin (A) in the present invention is a polymer compound having acid amide (-aonm-) as a repeating unit, and the polymerization method is one obtained by ring-opening polymerization of cy(])lactam. Examples include those resulting from polycondensation of aminocarboxylic acids, and (3) those resulting from polycondensation of diamines and dibasic acids.

These have the common name nylon/, and include, for example, nylon 6, nylon 12, nylon 9, nylon 11, nylon 66, nylon 610, etc. Among these, nylon 6 and nylon 66 are preferred. or,
The molecular weight of the polyamide is not particularly limited, but one having a relative viscosity (ηre) of CL5 or higher, preferably 2.0 or higher is usually used.

The modified polyolefin (A) in the present invention is one in which an unsaturated carboxylic acid or a derivative thereof is grafted to the above-mentioned mixture of polyolefin and polyamide, usually in an amount of 1001 to 10 weight percent, preferably 11 to 5 weight percent. As unsaturated carboxylic acids or derivatives thereof,
or Examples thereof include acid anhydrides and esters.

Various known methods can be used to graft the unsaturated carboxylic acid or its derivative onto the mixture of polyolefin and polyamide. For example, an unsaturated carboxylic acid or a derivative thereof and a reaction initiator such as an organic peroxide are added to a polyolefin and then melt-kneaded, or a polyolefin is dissolved in a solvent and an unsaturated carboxylic acid or a derivative thereof and a reaction initiator are added to the polyolefin. A method of adding and reacting is preferred.

In this case, the mixing ratio of polyolefin and polyamide is
10-950-95 parts by weight or 20-90% by weight, and 90-5% by weight of polyamide, preferably 80-10% by weight. At the above mixing ratio, polyolefin is 100%
If the amount is less than 100% by weight, the water absorption rate increases, resulting in a decrease in physical properties such as elastic modulus and insufficient compatibility. On the other hand, a large amount of polyolefin exceeding 95% by weight is not preferable because compatibility becomes insufficient and physical properties deteriorate. The amount of the unsaturated carboxylic acid or its derivative and the organic peroxide used as a reaction initiator is 1 to 5 parts by weight of the unsaturated carboxylic acid or its derivative and the organic peroxide per 100 parts of the mixture of polyolefin and polyamide. The amount of oxide α00 is preferably 1 to 5 parts by weight.

In addition, melt crosstalk is the temperature at which each component melts, usually 180°C.
It is carried out at ~300°C using an extruder, Banbury mixer, roll, etc. In this manner, a modified polyolefin (A) in which a polyolefin and a polyamide are bonded via a graft reaction via an unsaturated carboxylic anhydride is obtained.

As the polyamide (B)) in the present invention, the same polyamide as used for the above-mentioned modified polyolefin (A) can be used. Moreover, the same polyolefin as the polyolefin used for the modified polyolefin (A) can be used as the polyolefin (0).

In the present invention, the low crystalline ethylene-α-olefin copolymer Φ) includes ethylene, propylene, butene-
1, α-olefin copolymers such as pentene-1, hexene-1,4-methylpentene-1, or ethylene, α-
Copolymer with olefin and non-conjugated diene, etc., ethylene content 30-85% by weight, Mooney viscosity ML1+8
(127℃) 5-500, crystallinity (X-ray diffraction method) 4
Low crystallinity or non-crystallinity of 0% or less is preferred. Suitable examples include ethylene-propylene copolymer,
Ethylene-butene-1 copolymer, propylene-butene-1
1 copolymer, ethylene-propylene-diene combined s
rubber-like substances. Further, part or all of the above-mentioned low-crystalline or non-crystalline ethylene-α/olefin copolymer may be chemically modified with an unsaturated carboxylic acid or a derivative thereof. Further, the low crystalline ethylene-α-olefin copolymer may be filled with other polyolefins such as polyethylene. Incorporation of such a low-crystalline ethylene-α-olefin copolymer improves the low-temperature impact strength of the composition, and modified products thereof are particularly effective.

Next, the blending ratio of the composition of the present invention is 5 to 95 parts by weight (modified polyolefin), preferably 10 to 901 parts by weight,
Polyamide 03) 5 to 95 parts by weight, preferably 10 to 95 parts by weight
90 parts by weight, 0 to 90 parts by weight of polyolefin (C), preferably 0 to 80 parts by weight, and (A)+CB)+(C)=
Low crystalline ethylene-α-olefin copolymer ■) 5 to 80 parts by weight, preferably 10 to 6 parts by weight per 100 parts by weight
0 weight 1 part, and the polyolefin unit in the composition [
The total amount of the polyolefin component in component (A) and the polyolefin in component (C) is 10 to 9% by weight, and the desired L< is 20 to 80% by weight. If the modified polyolefin (A) is less than 5 parts by weight, the compatibility will not be improved, while if it exceeds 1 part by weight, mechanical properties will deteriorate and coloring will easily occur, so this is preferable. ) is less than 5 parts by weight, it depends on the polyamide. No improvements in rigidity, impact resistance, heat resistance, gas barrier properties, etc. were obtained;
If the amount exceeds 1 part by weight, the effect of improving the hygroscopicity, chemical resistance, etc. of polyamide cannot be obtained. Also, low crystallinity ethylene-
If the α-olefin copolymer (D) is less than 5 parts by weight, the temperature is low! The effect of improving one-shot strength is insufficient, and on the other hand, if it exceeds 80 parts by weight, strength, rigidity, heat resistance, surface hardness, etc. are impaired. Further, if the polyolefin unit in the composition is less than 10% by weight, the effect of improving moisture resistance, chemical resistance, etc. due to the polyolefin cannot be obtained, while if it exceeds 90% by weight, no improvement in physical properties due to polyamide deformation can be obtained.

The composition of the present invention can be produced using the modified polyolefin (
A), polyamide (B), polyolefin (C), and low crystalline ethylene-α-olefin copolymer CD) are uniformly mixed in the above blending ratio, and the mixture is melt-kneaded. . For example, the previous components are premixed in advance using a Henschel mixer, ribbon blender, mixer blender, etc., and this mixture is passed through an extruder,
A preferred method is to knead the ingredients using a Banbury mixer, rolls, etc. at a temperature at which each component melts, for example 180 to 300°C, and then pelletize or grind the mixture.

The composition of the present invention may contain a heat stabilizer, an ultraviolet absorber, a nucleating agent, an antistatic agent, a lubricant, a flame retardant, a coloring agent, an inorganic filler, a plasticizer, etc. within a range that does not impair the purpose of the present invention. Good too.

These additives may be added during or after the preparation of the composition.

EXAMPLES Next, the present invention will be explained in detail with reference to examples. In addition,
All parts and units in the examples are based on weight, and the test method is as follows.

(υMFR:, 7210 for T-work 13 (load 2.16 kg
, 230'4) (2) Tensile strength, tensile elongation at break: AS
TM D 638 (3) Izot impact strength: AST
M D 256 (-30℃) Notched (4) Gloss: ASTM D 523 (
5) Water absorption: A test piece was immersed in warm water at 50°C for 10 hours, and calculated from the difference in weight between the test piece when it was molded (dry state) and after immersion.

Crystalline homopolypropylene (MFR=A5r/10 min,
(hereinafter referred to as homo-PP), crystalline propylene-ethylene block copolymer (MFR = ha t/10 min, ethylene content = 7%, hereinafter referred to as block PP), nylon 6 (hereinafter referred to as block PP),
Relative viscosity = 2.60 or less N76) and nylon 66 [manufactured by Kou C Kosha, Maranyl Al25 (trade name) or less N766
] are blended in the combinations and proportions shown in Table 1, and maleic anhydride (hereinafter MA
) or endobicyclo-(2,2,1-5-hebutene-2,3 dicarboxylic anhydride C, hereafter referred to as HA) and an organic peroxide [manufactured by NOF Corporation, Percumil H (trade name) and below. After adding 3 parts of α (referred to as P and O) and mixing in advance at room temperature with a Henschel mixer, 2 parts of
The mixture was fed to a shaft press ratio machine and mixed at 220°C to form pellets. The acid addition amount and MPPR of the obtained modified polypropylene (hereinafter referred to as modified PP) were compared with that of modified homo PP (I132
Unfortunately, MFR=9.5r/10min) and modified block PP
(1136%, MyR=a2y/1o min).

Production of modified low-crystalline ethylene-α-olefin copolymer Ethylene-propylene random copolymer [MFR=16
r/10 min, ethylene content = 70%, Mooney viscosity ML
1+4 (1o o℃) 70 or less referred to as KF-1] 80
20 parts of high-density polyethylene (density = 0.946, M = 5 r/10 minutes, referred to as HDPK), MA1
Part and P, 0 part and 2 parts are mixed in advance, and then melt-kneaded at 200°C to obtain a modified low-crystalline ethylene-α-olefin copolymer composition (acid addition amount = 0.40%, below)! 1P-
2) was obtained.

Production of the composition modified homopp1 modified block PPXN76, N766,
Homo PP, block pp, zp-1, and EP-2 were blended in the combinations and proportions shown in Table 1, mixed in advance at room temperature with a Henschel mixer, and then fed to a twin-screw press ratio machine.
Crosstalk was performed at 0°C to form pellets. A test piece was molded from the obtained composition by injection molding and its physical properties were measured, and the results are shown in Table 1.

For comparison, when the low-crystalline ethylene-α/olefin copolymer is not included (comparative row 1), when the polypropylene component in the composition is less than 10% (comparative example 2), when polyamide is added to the modified PP, (Comparative Example 3), when the composition does not contain polyamide ■) (Comparative flJ4)
and modified polypropylene (A) at 10% by weight in the composition.
In the case where the composition was less than (Comparative Example 5), a composition was prepared in the same manner, and the physical properties of the obtained composition are also listed in Table 1. As is clear from the results, these compositions have inferior physical properties.

In addition, when the cross sections of the compositions of Example 2 and Comparative Example 2 were extracted with formic acid and the Ny6 phase was eluted, the Ny6 of Example 2 was observed using a scanning microinvasive photograph. It was observed that the size of the dispersed phase was finer and more uniformly dispersed than in the case of the conventional method.

Effects of the Invention The composition of the present invention has a finer and more uniform dispersion size of polyolefin and polyamide than conventional compositions, and has improved compatibility, and has excellent mechanical properties, especially impact resistance and surface gloss, and has good water absorption. It is low.

Due to the above-mentioned properties, the composition of the present invention is suitable for various industrial materials, particularly automobile parts, household appliance parts, and the like.

Claims (1)

[Claims] 10 to 95% by weight of polyolefin and 90 to 5% by weight of polyamide
Modified polyolefin (A) obtained by reacting an unsaturated carboxylic acid or a derivative thereof with a mixture consisting of
95 parts by weight, 5 to 95 parts by weight of polyamide (B), 0 to 90 parts by weight of polyolefin (C) [However, (A) + (B) +
(C) = 100 parts by weight and low crystalline ethylene -α-
Consisting of 5 to 80 parts by weight of olefin copolymer (D),
and the polyolefin unit in the composition is 10 to 90% by weight
A thermoplastic resin composition.