JP2678382B2 - Interior and exterior parts for automobiles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to interior parts such as instrument panels and consoles of automobiles, or exterior parts such as front grilles and moldings, and in particular to thermoplastic resin compositions. The present invention relates to a resin interior / exterior part obtained by molding.

(Prior Art) Interior parts and exterior parts of automobiles are often resin molded products. Various materials are used for the material, among them, aromatic vinyl compound-based thermoplastic resin,
In particular, rubber-modified styrene-based thermoplastic resins are widely used for interior and exterior parts for automobiles because they are lightweight and have excellent moldability.

(Problems to be Solved by the Invention) However, the rubber-modified styrene-based thermoplastic resin is
It is not always stable against organic solvents. On the other hand, automobile interior and exterior parts are often adhered with automobile fragrances, leather waxes and the like containing ethanol or methanol as a solvent component. Therefore, cracks may occur in the interior / exterior parts for automobiles, which are molded products of the rubber-modified styrene-based thermoplastic resin, causing problems in appearance and function.

As a means for improving the chemical resistance of such rubber-modified styrene-based thermoplastic resin, conventionally, a method of increasing the molecular weight or a polymer having a polar group-containing monomer such as vinyl cyan compound or (meth) acrylic acid ester is used. Although methods of introducing them into the inside are also known, sufficient chemical resistance has not yet been obtained by those methods.

As another method for improving the chemical resistance of the rubber-modified styrene-based thermoplastic resin, it is conceivable to add an aromatic polyester, but even in such a case, the physical property balance level between chemical resistance and impact resistance However, there is a drawback that the appearance of the molded product near the game is not good yet.

The present invention has been made in view of such a problem, and an object thereof is to obtain an automobile interior / exterior component having excellent chemical resistance and impact resistance, and having a good appearance after molding. .

(Means for Solving the Problems) In order to achieve this object, in the present invention, a rubber-modified styrene-based thermoplastic resin is blended with an aromatic polyester, a specific graft copolymer, and a silicone-based lubricant in a specific ratio. By using the thermoplastic resin composition obtained as described above, interior and exterior parts for automobiles are molded.
That is, the interior / exterior parts for automobiles according to the present invention include (A) (A) rubber-modified styrene thermoplastic resin 54 to 74.5
% By weight, (B) 25-40% by weight of an aromatic polyester having an intrinsic viscosity of 1.1-1.4 at 25 ° C. in an o-chlorophenol solvent, and (C) mainly composed of an olefin unit and an epoxy group-containing unsaturated compound unit. Aromatic vinyl compound 60 ~
Graft copolymer 0.5 to 6 obtained by graft-polymerizing a monomer consisting of 80% by weight and a vinyl cyanide compound 20 to 40% by weight.
%, And (D) 50 to 20,000 ppm of the silicone-based lubricant with respect to the total of the components (A), (B) and (C), and a thermoplastic resin composition obtained from the respective components. There is a feature.

Further, the interior and exterior parts for automobiles according to the present invention are prepared by previously mixing a part or all of the above-mentioned component (B), a part or all of the component (C), and 0 to 20% by weight of the component (A). It is characterized by being a molded article obtained by molding the above-mentioned thermoplastic resin composition obtained by mixing the remaining components with the mixture.

(Specific Description of the Invention) Next, each component of the thermoplastic resin composition used in the present invention will be specifically described.

1) Rubber-modified styrene-based thermoplastic resin which is the component (A) of the present invention The rubber-modified styrene-based thermoplastic resin used as the component (A) in the present invention is a rubber-modified styrene-based polymer or a rubber-modified styrene-based polymer. It is a mixture of a polymer and a styrene polymer (not modified with rubber), and is a mixture of a rubber polymer and a styrene polymer for the purpose of obtaining a high degree of impact resistance. The mixing method may be a simple mechanical Brent method, but in order to obtain good compatibility, a so-called graft copolymerization in which a styrene-based monomer or the like is graft-copolymerized in the presence of a rubbery polymer is used. Those obtained by the formulation are more preferable. Further, it is also preferable to use a rubber-kneaded styrene polymer (graft polymer) obtained by the method and a styrene polymer obtained by a separate method, that is, a so-called graft-blend method.

Examples of the type of rubbery polymer used include polybutadiene, styrene butadiene copolymer, hydrogenated styrene-butadiene block copolymer, acrylic copolymer, ethylene-propylene copolymer, chlorinated polyethylene, polyurethane. Among them, it is preferable to use polybutadiene.

Examples of the styrene-based monomer include styrene, α-methylstyrene, bromostyrene and the like, and among these, it is optimal to use styrene and / or α-methylstyrene.

Furthermore, if necessary, these styrene-based monomers and other copolymerizable other monomers can be used for copolymerization. Such monomers include acrylonitrile, methacrylonitrile, methyl methacrylate, N-
And cyclohexylmaleimide.

In general, impact resistance is difficult to develop with a styrene-based monomer alone, so it is preferable to copolymerize acrylonitrile. In this case, the composition ratio of the aromatic vinyl compound and the vinyl cyanide compound is preferably 60 to 90/10 to 40% by weight, more preferably 65 to 85/15 to 35% by weight.

Specific examples of the rubber-modified styrene-based thermoplastic resin thus obtained include conventional acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-ethylenepropylene-styrene resin (AES resin), and methyl methacrylate-butadiene. -Styrene resin (MBS resin), acrylonitrile-butadiene-methyl methacrylate-styrene resin, acrylonitrile-n-butyl acrylate-styrene resin (AAS resin), rubber-modified polystyrene (high impact polystyrene: HIPS), α-
Heat-resistant rubber-modified styrene resin using methyl styrene,
A styrene-butadiene block copolymer or a styrene-based graft copolymer modified with a hydrogenated product thereof may, for example, be mentioned.

The above rubber-modified styrene thermoplastic resin is produced by emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization, or the like.

The production method is, for example, a graft copolymer obtained by graft-polymerizing a styrene-based monomer and, if necessary, another monomer in the presence of a rubbery polymer such as polybutadiene (however, not grafted. Of the styrene-based polymer) or a styrene-based polymer obtained by polymerizing the styrene-based monomer and optionally other monomer in the absence of the rubbery polymer. It is manufactured by mixing.

The rubber content in the rubber-modified styrene-based thermoplastic resin is preferably 5 to 40% by weight, more preferably 10 to 30%.
% By weight.

The intrinsic viscosity ([η] 30 ° C MEK unit dl / g) of the soluble component of methyl ethyl ketone in the rubber-modified styrene-based thermoplastic resin measured at 30 ° C in methylethylketone is 0.2 to 1.
2 is preferable, and 0.3 to 1.0 is more preferable.

In the graph and the polymer in the rubber-modified styrene thermoplastic resin, the ratio (graft ratio) of the resin component directly graft-bonded to the rubber component (graft ratio) is measured by solvent fractionation using acetone. It is preferable that the graft ratio is 40 to 150% because an automobile interior / exterior part having more excellent physical properties such as chemical resistance and impact resistance can be obtained. The graft ratio is more preferably 45 to 130.
%, Particularly preferably 50 to 120%.

Further, when the amount of α-methylstyrene in the rubber-modified styrene-based thermoplastic resin is 25 to 70% by weight, it is possible to obtain a more excellent interior / exterior part for automobiles because of a better balance of physical properties of chemical resistance and impact resistance. preferable.

2) Aromatic Polyester as Component (B) of the Present Invention As an example of the aromatic polyester used as the component (B) in the present invention, an aromatic dicarboxylic acid ester or its ester-forming derivative and a diol are known. And the like.

Examples of the aromatic dicarboxylic acid include naphthalene-
Naphthalenedicarboxylic acids such as 2,6-dicarboxylic acid, terephthalic acid, isophthalic acid, p-hydroxybenzoic acid,
Adipic acid and sebacic acid and their ester-forming derivatives are mentioned.

Examples of the diol include ethylene glycol, 1,
2-6 such as 4-butanediol and 1,6-hexanediol
Polymethylene glycol having 1 carbon atom, or 1,
4-Cyclohexanediol, bisphenol A, and their ester-forming derivatives are mentioned.

Specific examples of the aromatic polyester thus obtained include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), bisphenol A isophthalate and the like. Of these, PBT is preferable.

Among such aromatic polyesters, those used in the present invention are 25% in an o-chlorophenol solvent.
The intrinsic viscosity at [℃] ([η] 25 ℃ o-chlorophenol unit dl / g) is 1.1 to 1.4, and if it is within this range, the impact resistance and chemical resistance of automobile interior and exterior parts obtained are Good balance.

3) Graft copolymer which is the component (C) of the present invention The graft copolymer used as the component (C) in the present invention is obtained by copolymerizing a compound mainly composed of an olefin compound and an epoxy group-containing unsaturated compound. 60 to 80% by weight of aromatic vinyl compound and vinyl cyanide compound in the main chain polymer
It is a graft copolymer having a multiphase structure obtained by graft-polymerizing 20 to 40% by weight of a monomer.

Examples of the olefin used for the main chain copolymer include ethylene, propylene, and butene-1, and ethylene is particularly preferably used.

Examples of the epoxy group-containing compound include unsaturated glycidyl esters, unsaturated glycidyl ethers, epoxy alkenes, p-glycidyl styrenes and the like, and glycidyl methacrylate is particularly preferably used.

The weight ratio of the olefin and the epoxy group-containing unsaturated compound in the main chain copolymer, that is, the ratio of olefin component: epoxy group-containing unsaturated compound is preferably 99.9: 0.1 to 60:40, more preferably 97: 3 to It is 70:30.

The components grafted to the main chain copolymer are an aromatic vinyl compound at 60 to 80% by weight and a vinyl cyanide compound at 20 to 40% by weight.
% By weight. If the aromatic vinyl compound content is less than 60% by weight or more than 80% by weight, or if the vinyl cyanide compound is more than 40% by weight or less than 20% by weight, the impact resistance of the interior / exterior parts for automobiles is Is inferior, which is not preferable.

As the aromatic vinyl compound, for example, styrene, α-
Methylstyrene and the like can be mentioned.

Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile.

The weight ratio of the main chain copolymer component to the graft component used in the production of the graft copolymer (C) of the present invention is preferably from 95: 5 to 30:70.

As a preferred method for producing the graft copolymer of the component (C) used in the present invention, for example, a method of adding a styrene-acrylonitrile polymer having a -0-0-bond in the molecule to an olefin copolymer, for example, A copolymer of a radically polymerizable unsaturated compound having a peroxide bond, an aromatic vinyl compound and a vinyl cyanide compound, together with an ethylene-epoxy group-containing unsaturated compound polymer, by a radical addition reaction in an extruder or a solution. How to graft,
Alternatively, there is a method of graft-polymerizing a monomer composed of an aromatic vinyl compound and a vinyl cyanide compound onto an olefin copolymer.

4) Silicone-based lubricant which is the component (D) of the present invention. Examples of the silicone-based lubricant used in the component (D) of the present invention include polydimethylsiloxane and polymethylphenylsiloxane. It is preferable that the viscosity at 23 ° C. is 90 to 13,000 cp.

Composition ratio of each component in the thermoplastic resin composition used in the present invention, mixing method, and other substances that can be added as necessary, and automobile interiors and exteriors of the present invention obtained by molding the thermoplastic resin composition The parts will be described.

The rubber-modified styrene-based thermoplastic resin as the component (A) is
It is blended so as to be contained in the composition in an amount of 54 to 74.5% by weight. If it is less than 54% by weight, the impact resistance of the obtained automobile interior / exterior parts is lowered, which is not preferable. Also, 7
If it exceeds 4.5% by weight, the chemical resistance of the interior / exterior parts for automobiles deteriorates, which is not preferable.

The aromatic polyester as the component (B) is blended so as to contain 25 to 40% by weight in the composition. If it is less than 25% by weight, the chemical resistance of the obtained automobile interior / exterior parts is lowered, which is not preferable. On the other hand, if it exceeds 40% by weight, the impact resistance of the interior / exterior parts for automobiles decreases, which is not preferable.

The graph copolymer, which is the component (C), has a content of 0.
It is blended so as to contain 5 to 6% by weight. If it is less than 0.5% by weight or exceeds 6% by weight, impact resistance of the obtained automobile interior / exterior parts is deteriorated, which is not preferable.

The silicone-based lubricant as the component (D) has a remarkable effect in improving the impact resistance of the interior and exterior parts for automobiles.
50 to 2 with respect to the composition comprising each of the components (B) and (C)
It is 0,000 ppm, preferably 100 to 10,000 ppm. If it is less than 50 ppm or exceeds 20,000 ppm, the impact resistance of automobile interior and exterior parts will be poor.

A preferable mixing method of these components (A), (B), (C) and (D) is as follows:
Part or all of the component (C) and 0 to the component (A).
This is a method of previously mixing 20% by weight of the pre-stage components and then mixing the remaining components with the mixture. By using the thermoplastic resin composition thus obtained, it is possible to obtain the interior / exterior parts for automobiles, which is the object of the present invention, and has further excellent physical properties.

As the manufacturing method, the components of the preceding stage are mixed in advance by using a mixing device described below and a mixing operation, and the mixture and the remaining components are mixed using the device described below, or two or more charging ports are provided. A method of mixing the remaining components in the former components by first supplying the former components using an extruder and then supplying the remaining components from another charging port can be mentioned.

Mixing Device / Mixing Operation The mixing device for obtaining the thermoplastic resin composition used for the automobile interior / exterior parts of the present invention is not particularly limited, but includes, for example, a Banbury mixer, a Brabender plast mill, a kneader, and a vent. Various mixing devices generally used for mixing thermoplastic resins, such as an extruder, can be used. Among these, the method using a vented extruder is preferable.

The form of each component resin before mixing is not particularly limited, and any form such as pellets, beads, powder, flakes and the like can be mixed. However, the mixing temperature needs to be higher than the melting point of the aromatic polyester, while the rubber-modified thermoplastic resin is
Since it is thermally unstable at a temperature above 300 ° C, the mixing temperature is preferably 230 to 300 ° C.

Other compounding agents In addition to the above-mentioned essential components, the thermoplastic resin used for the interior / exterior parts for automobiles of the present invention may optionally contain a lubricant, an antistatic agent, an antioxidant, a flame retardant, and an ultraviolet absorber. ,
Compounding agents and additives generally used in this type of thermoplastic resin composition, such as a photo-oxidation inhibitor, a colorant, and an inorganic filler such as glass fiber, can be mixed.

Further, other polymers such as polyamide, polyethylene, polypropylene, polysulfone, polyethersulfone, polyimide, PPS, polyetheretherketone, vinylidene fluoride polymer, polyphenyl ether, etc. are appropriately blended according to the required performance. be able to.

Interior / exterior parts for automobiles The interior / exterior parts for automobiles according to the present invention can be applied to any parts for which ABS resin has been conventionally used. Examples of interior parts include instrument panel body, instrument panel related parts such as defroster garnish, meter visor, glove box, column cover, radio panel, front console and rear console, armrest, hand brake knob, etc. Console related parts, tailgate openers, fuel lid openers, bonnet openers, etc. opener related parts, reclining covers, reclining knobs, headrest lock guides, seat belt buckle cases, etc. seat related parts, door pockets, regulator handles, door speaker lids, etc. Door related parts, rear speaker box, first aid box, rear tray related parts such as rear side shelf. In addition to the front grille, examples of the exterior parts include malls such as a front wind molding and a door edge molding.

Molding Method The method of molding the interior / exterior parts for automobiles according to the present invention may be any of the conventional molding methods for thermoplastic resin molded products, but representative examples thereof include an injection molding method and a stamping molding method.

(Examples) Examples of the present invention will be described below, but these are merely examples and do not limit the content of the present invention. In each of the following examples, weight% is abbreviated as [%].

(A), (B) used in Examples and Comparative Examples of the present invention,
The components (C) and (D) are shown below 4.

1) Component (A) The component (A) used in the examples and comparative examples is a mixture of a rubber-modified stilne polymer and a styrene polymer (not rubber-modified). It is shown.

Rubber-modified styrene-based copolymer G-1: ABS resin consisting of 50% polybutadiene, 10% styrene-butanediene copolymer, 30% styrene, 10% acrylonitrile, 50% graft ratio, intrinsic viscosity (in methyl ethyl ketone at 30 ° C) (Similarly below) η = 0.5 G-2: ABS resin consisting of 30% polybutadiene, 10% styrene-butadiene copolymer, 45% styrene, 15% acrylonitrile, 100% graft ratio, [η] = 0.5 G-3: ABS resin consisting of polybutadiene 12%, styrene-butadiene polymer 5%, styrene 27%, α-methylstyrene 35%, acrylonitrile 21%, graft rate 100%,
[Η = 0.5] Styrenic copolymer (without rubber modification) M-1: 5% styrene, 25% acrylonitrile, and α-
AS resin consisting of 70% methyl styrene, [η] = 0.33 2) (B) component B-1: PBT resin Polyplastics Co., Ltd., trade name Geranex XD477, [η] = 1.23) (C) Component C-1: Ethylene-glycidyl methacrylate (hereinafter GM
(Abbreviation A) Copolymer (ethylene / GMA = 85/15) grafted with styrene-based polymer (ethylene + GMA / styrene-acrylonitrile copolymer = 70/30, styrene / acrylonitrile = 70/30%) 4) Component (D) D-1: Polydimethylsiloxane Examples 1 to 5 and Comparative Examples 1 to 6 Using the components of the formulation shown in Table 1, various thermoplastic resin compositions were obtained by the following method. It was

First, the components (B) and (C) were kneaded using a single-screw extruder at a temperature of 230 ° C. to obtain pellets, and then the components (A) and (D) were added to the pellets. This was kneaded using a twin-screw extruder at 230 ° C. (however, 270 ° C. in Example 3) to obtain a thermoplastic resin composition as a molding material.

Next, the obtained various molding materials were molded into a predetermined shape by injection molding to obtain a test piece.

Evaluation test method Chemical resistance ASTM No. 1 dumbbell was bent to a strain of 1.0%, fixed to a jig, and coated with Alfa Crystal (Chemical A) manufactured by Eikosha Co., Ltd. as an air freshener for automobiles. After standing in an atmosphere of 80 ° C. for 24 hours, the state of crack generation was visually evaluated.

Table 1 shows the results. The symbols in Table 1 represent the following states.

◎: No cracks generated ○: Small amount of microcracks generated △: Large number of microcracks generated ×: Large cracks generated or ruptured Even in a test using Honey Kiss, a product name of Nitto Kagaku Co., Ltd. as an aromatic agent for automobiles , Similar results were obtained.

Impact resistance Place a test plate (150 x 100 mm) with a 2.54 mm thick notch (R20 mm, depth 1 mm) on parallel support bases at 50 mm intervals and
A 2.7 mm weight was dropped at a speed of 6.7 m / sec, and the total energy required for destruction was measured.

 Table 1 shows the results.

(Effects of the Invention) As is clear from the above description, the interior / exterior parts for automobiles according to the present invention are highly balanced in chemical resistance, impact resistance, and appearance of molded articles. Therefore,
Compared with the conventional ones, it is possible to obtain extremely excellent interior and exterior parts for automobiles, and their industrial utility value is extremely large.

Claims (2)

(57) [Claims] 1. An interior / exterior part for an automobile, which is a molded product obtained by molding a thermoplastic resin composition obtained from the following components (A), (B), (C) and (D). (A) 54 to 74.5% by weight of rubber-modified styrenic thermoplastic resin. (B) 25-40% by weight of an aromatic polyester having an intrinsic viscosity of 1.1-1.4 at 25 ° C. in an o-chlorophenol solvent. (C) A copolymer mainly composed of an olefin unit and an epoxy group-containing unsaturated compound unit, and an aromatic vinyl compound 60 to
0.5 to 6% by weight of a graft copolymer having a multiphase structure obtained by graft-polymerizing a monomer comprising 80% by weight and a vinyl cyanide compound of 20 to 40% by weight. (D) A silicone lubricant of 50 to 20,000 ppm based on the total of the components (A), (B) and (C). 2. A part or all of the component (B),
Part or all of the component (C) and 0 to the component (A).
An interior / exterior part for an automobile comprising a molded product obtained by molding the thermoplastic resin composition according to claim 1, which is obtained by previously mixing 20% by weight and mixing the remaining components with the mixture.