JPH0532890A - High-fluidity resin composition - Google Patents

Abstract

PURPOSE:To provide a polyphenylene ether (PPE)/polyamide (PA) resin composition which is excellent in mechanical strength and melt fluidity and also in surface appearance of its molding. CONSTITUTION:The title composition comprises 100 pts.wt. PPE resin plus a polyamide resin in which the terminal carboxyl groups are more than the terminal amino groups in quantity and 3-50 pts.wt. aromatic vinyl resin containing oxazolinyl groups.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition containing a polyphenylene ether (hereinafter sometimes referred to as PPE) resin and a polyamide (hereinafter sometimes referred to as PA) resin. More specifically, it relates to the above resin composition having excellent mechanical strength and melt flowability, and having a good appearance of a molded product.

[0002]

BACKGROUND OF THE INVENTION PPE is useful as a resin for molding materials because of its excellent mechanical and electrical properties,
Insufficient oil resistance. To improve this point, PP
It is known to mix E with polyamide having good oil resistance (for example, JP-A-56-16525). But P
Since PE and PA are poorly compatible with each other, in a molded article molded from a resin composition in which these are mixed, the characteristics inherent to both resins, for example, good mechanical characteristics are not exhibited,
There is also the problem of poor appearance.

In order to improve this point, an unsaturated carboxylic acid such as maleic anhydride or its derivative is added as a compatibilizing agent to a resin composition comprising PPE and polyamide to improve the oil resistance and impact resistance. Attempts have been made to improve the properties (JP-A-56-26913).

Further, it is known to add a saturated aliphatic polycarboxylic acid as a compatibilizing agent (Tokusho Sho 61-50).
2195).

Further, JP-A-63-10655 and Japanese Patent Application No. 1-
No. 115172 discloses adjusting the amount of terminal amino groups of a polyamide to be larger than the amount of terminal carboxyl groups to improve compatibilization.

However, when the above-mentioned compatibilizing agent is used and when the above-mentioned polyamide in which the amount of terminal amino groups is adjusted is used, the melt fluidity is lowered, resulting in a problem of poor moldability. ..

Therefore, an object of the present invention is to provide a resin composition containing PPE and polyamide, which has excellent mechanical strength and melt flowability and has a good surface appearance of a molded product.

[0008]

The present inventors have found that PPE /
As a result of extensive studies on PA-based resin compositions, excellent mechanical strength and excellent mechanical strength were obtained by using a polyamide in which the amount of terminal carboxyl groups was greater than the amount of terminal amino groups and adding an oxazolinyl group-containing aromatic vinyl resin. PP with melt flowability and good surface appearance of molded products
The inventors have found that an E / PA resin composition can be obtained, and have reached the present invention.

That is, the resin composition of the present invention comprises (A) 5 to 80 parts by weight of a polyphenylene ether resin, and (B) 95 to 20 parts by weight of a polyamide resin having a terminal carboxyl group amount larger than the terminal amino group amount. And (C) the oxazolinyl group-containing aromatic vinyl resin in an amount of 3 to 5 relative to 100 parts by weight of the total of (A) and (B).
It contains 0 parts by weight.

First, in the present invention, known PPE resins can be used. The PPE resin is, for example, a compound represented by the general formula (Formula 1):

[0011]

[Chemical 1] (In the formulas, R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or at least 2 between the halogen atom and the phenyl ring.
A haloalkyl group having 1 carbon atom (s) or a haloalkoxy group represents a monovalent substituent selected from those containing no tertiary α-carbon, and q is an integer representing the degree of polymerization). It is a general term, and may be a single kind of the polymer represented by the above general formula or a copolymer in which two or more kinds are combined. In a preferred embodiment, R ₁ and R ₂ are alkyl groups having 1 to 4 carbon atoms, and R ₃ and R ₄ are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. For example, poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4) -
Phenylene) ether, poly (2-methyl-6-propyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly (2-ethyl-
6-propyl-1,4-phenylene) ether, and the like. As the PPE copolymer, there may be mentioned a copolymer partially containing an alkyl trisubstituted phenol, for example, 2,3,6-trimethylphenol, in the above polyphenylene ether repeating unit. In addition, for these PPE,
It may be a copolymer grafted with a styrene compound. The styrene compound-grafted polyphenylene ether is a copolymer obtained by graft-polymerizing the above PPE with a styrene compound such as styrene, α-methylstyrene, vinyltoluene, and chlorostyrene.

Next, the (B) polyamide resin used in the present invention includes, for example, nylon-4, nylon-6, nylon-6,6, nylon-12, nylon-6,10. Not limited to. What is essential in the present invention is to use a polyamide having more terminal carboxyl groups than terminal amino groups. The equivalent ratio of terminal carboxyl group / terminal amino group is preferably 1.01 or more,
It is more preferably 1.3 or more. The terminal group can be adjusted by adjusting and adding an amount of a compound having a group that reacts with an amino group, for example, a dicarboxylic acid during polymerization of polyamide. Alternatively, it can also be carried out by reacting, for example, a compound having a group reactive with an amino group after the polymerization of polyamide.

The amount of terminal carboxyl groups of the polyamide resin was measured by dissolving the sample in hot benzyl alcohol and performing neutralization titration with a N / 20 NaOH aqueous solution using a phenolphthalein indicator. Further, the amount of terminal amino group was measured as follows. That is, a polyamide resin sample was dissolved in m-cresol, purged with nitrogen and dissolved at 80 ° C., then a methanol solution of thymol blue as an indicator was dropped, and then titrated with paratoluenesulfonic acid.

In the present invention, 95 to 20 parts by weight of (B) relative to 5 to 80 parts by weight of component (A), preferably 80 to 30 parts by weight of (B) relative to 20 to 70 parts by weight of (A). Compound. If the amount of (A) is too small, the mechanical properties will deteriorate, and if the amount of (B) is too small, the oil resistance will decrease.

Next, the component (C) used in the present invention will be described. The component (C) is a copolymer containing an unsaturated monomer component having an oxazolinyl group and an aromatic vinyl monomer component. Examples of the oxazolinyl group-containing unsaturated monomer include those represented by the general formula (Formula 2)

[0016]:

[Chemical 2] And examples of Z include those containing a polymerizable double bond. Preferred substituents Z are the following group (Formula 3).

[0017]

[Chemical 3] R in these formulas is a hydrogen atom or an alkyl group or an alkoxy group having 1 to 6 carbon atoms, for example, a methyl group, i- and n-propyl groups or a butyl group.

Particularly preferred compounds have the general formula (Formula 4):

[0019]

[Chemical 4] In the vinyloxazoline represented by, R has the above-mentioned meaning and is preferably a hydrogen atom or a methyl group.

As the aromatic vinyl monomer, styrene, α-methylstyrene, p-methylstyrene, pt-
Butyl styrene and the like can be mentioned, and styrene is preferable.

In the above component (C), the proportion of the unsaturated monomer having an oxazolinyl group depends on the appearance and mechanical strength of the resin composition when it is too small, and the viscosity is increased when it is too large. Considering the deterioration of fluidity, the content is preferably 0.001 to 30% by weight.

In the component (C), 0 to 100 parts by weight of the total amount of the unsaturated monomer having an oxazolinyl group and the aromatic vinyl monomer is added to the other copolymerizable monomer component. 70 parts by weight can be included. Examples of such other monomer components include vinyl acetate, acrylic acid (salt), methacrylic acid (salt), acrylic acid ester, methacrylic acid ester, (anhydrous) maleic acid, maleic acid ester, 2-norbornene- Unsaturated carboxylic acids such as 5,6-dicarboxylic acid (anhydride) or derivatives thereof; ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1 Α-olefin components such as -decene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene; butadiene, isoprene, 1,4-hexadiene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene Diene components such as; vinyl cyanide-based monomers such as acrylonitrile.

There are no particular restrictions on the method for producing the copolymer of component (C), and bulk polymerization, solution polymerization, bulk suspension polymerization,
Known methods such as suspension polymerization and emulsion polymerization are used.

The component (C) is 3 to 50 parts by weight, preferably 5 to 5 parts by weight, based on 100 parts by weight of the total of (A) and (B).
40 parts by weight are contained. If the amount of component (C) is too small, the melt fluidity will not improve, and if it is too large, the heat resistance will decrease.

In the resin composition of the present invention, other conventional additives such as pigments, dyes, etc. may be added according to the purpose at the time of mixing the resin and molding, as long as the physical properties are not impaired.
Reinforcing agents, fillers, heat resistance agents, antioxidants, weathering agents, lubricants, mold release agents, crystal nucleating agents, plasticizers, flame retardants, fluidity improvers, antistatic agents, impact resistance improvers, etc. are added. can do.

The method for producing the resin composition of the present invention is not particularly limited, and ordinary methods can be satisfactorily used. However, melt mixing is generally preferred. Any melt mixing method can be used provided it can process the molten viscous mass. The method is used in a batch system or a continuous system. In particular, an extruder, a Banbury mixer, a roller, a kneader and the like can be mentioned as examples.

[0027]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

The following compounds were used in the following examples and comparative examples. Ingredient (A) PPE ... Intrinsic viscosity (chloroform, 25 ° C) 0.48 dl /
Poly (2,6-dimethyl-1,4-phenylene) ether of g Component (B) Polyamide ... PA-1: Relative viscosity 2.6, terminal carboxyl group amount 7.0
× 10 ^-5 mol / g, the amount of terminal amino groups is 4.6 × 10 ^-5 mol / g
Nylon-6 PA-2 having a relative viscosity of 2.6 and a terminal carboxyl group amount of 2.5.
× 10 ^-5 mol / g, the amount of terminal amino groups is 9.3 × 10 ^-5 mol / g
Nylon-6 (used for comparison) Component (C) Copolymer of oxazolinyl group-containing monomer and styrene (content of oxazolinyl group-containing monomer 5% by weight, trademark; RPS-1005, Nippon Shokubai Kagaku Co., Ltd. Polystyrene (used for comparison, trademark; CR350
0, manufactured by Dainippon Ink and Chemicals, Inc.) Example 1 and Comparative Examples 1 to 3 Using a twin-screw extruder (screw diameter 30 mm), a mixture prepared by mixing the components in the amounts (parts by weight) shown in Tables was used. 280 ° C, 4
Extruded at 50 rpm to make pellets. The pellets were molded with an injection molding machine in which the cylinder temperature was 280 ° C. and the mold temperature was 80 ° C. to prepare test pieces. Tensile strength (ASTM D638) and bending strength (ASTM D790) were measured using the obtained test piece. Also,
The surface appearance was evaluated by visually observing the surface of a 50 × 50 × 3 mm test piece. Further, the melt index (MI) of the resin composition (measured at 280 ° C. under a load of 5 kg according to ASTM D1238) was also measured.
The results are shown in Table 1.

[0029]

[Table 1] From Table 1, Comparative Example 1 in which the polyamide is within the scope of the present invention but does not use the component (C) at all has a remarkably low melt fluidity and a poor surface appearance. Further, although the component (C) according to the present invention was used, when a polyamide outside the scope of the present invention, that is, having a terminal carboxyl group amount less than the terminal amino group amount was used (Comparative Example 2), and the component (C) was oxazolinyl. When polystyrene containing no group is used (Comparative Example 3), the melt fluidity is improved, but the surface appearance is poor and the mechanical strength is also low. On the other hand, in Example 1 using the resin composition of the present invention, good appearance, excellent mechanical strength and melt flowability were obtained.

[0030]

The PPE / PA resin composition of the present invention is
Since it has excellent mechanical strength and melt flowability and the surface appearance of the molded product is good, it can be used in a wide range of applications and has high industrial utility.

Claims (1)

Claims (A) Polyphenylene ether resin (A)
5 to 80 parts by weight, and (B) 95 to 20 parts by weight of a polyamide resin having a terminal carboxyl group amount larger than the amount of terminal amino groups, and (C) an oxazolinyl group-containing aromatic vinyl resin (A) and ( 3-5 for 100 parts by weight of B) in total
A resin composition containing 0 part by weight.