JPH05117457A - Polypropylene composite material for automobile - Google Patents

Abstract

PURPOSE:To provide the title material which is improved in correcting such a shortcoming of the conventional polypropylene composite material for an automobile that it has poor moldability and which is excellent in the prevention of the deposition of dust, the prevention of haze, and thermal oxidation stability. CONSTITUTION:The title material containing an inorganic filler, which comprises a mixture of 100 pts.wt. crystlline polypropylene with an antioxidant having a weight loss initiation temperature of 150 deg.C or higher, a metal inactivator, and hydrotalcite each in an amount of 0.01-10 pts.wt. and 0.01-15 pts.wt. metal carbonate having a surface treated with an 8-28C fatty acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to automotive polypropylene composites. More specifically, the present invention relates to a polypropylene composite material for automobiles having excellent antifogging property and moldability, and further relates to a polypropylene composite material for automobiles having improved dust adhesion prevention property and thermal oxidative stability in addition to the above properties.

[0002]

2. Description of the Related Art For automobile meter cases, the material is changed from ABS resin to polypropylene composite material mainly for cost reduction. When polypropylene composite materials are used for automobile molded products such as automobile meter cases,
Conventionally, many problems have occurred. For example, antioxidants, neutralizing agents, metal deactivators and dispersants that are commonly used as essential additives for polypropylene composites cause fog in meter panels due to their volatile components. In particular, higher fatty acid salts and waxes used as a neutralizing agent and a dispersant are liable to cause fog and have a drawback of making it difficult to distinguish the meter display. On the other hand, a polypropylene composite material that does not use a dispersant has poor pigment dispersibility and poor mold releasability during molding, resulting in poor moldability.

[0003] Polypropylene and its composite material have excellent electric insulation, but on the other hand, it is known that static electricity is easily charged during molding, which causes various obstacles. In addition, the molded product is easily contaminated with dust due to electrostatic charge, and the lightning pattern stain adheres strongly, which significantly reduces the commercial value. In the case of an automobile meter case, dust that adheres causes insufficient light quantity and makes it difficult to distinguish the meter display.

Further, the polypropylene composite material containing an inorganic filler has a drawback that the thermal oxidative stability is remarkably lowered as compared with a polypropylene composite material containing no filler. It is considered that this is because the added thermal oxidation stabilizer is inactivated by the inorganic filler. On the other hand, a sheet using an additive having a weight loss starting temperature of 150 ° C. or higher in order to prevent roll contamination (Japanese Patent Laid-Open No. Sho 6-96
No. 2-132937) or a container containing a specific stabilizer for imparting thermal stability (JP-A-1-30173).
No. 9) is known. Further, an antistatic agent for synthetic resins using a sodium alkylbenzene sulfonate and a wax is known (JP-A-62-36466 and JP-A-1-54068).

As a method for improving the releasability of a composite material, there is a technique for improving the releasability by blending a filler with polypropylene (Japanese Patent Application No. 2-251175). Improvement is required. Although much research has been done so far to improve the moldability of such polypropylene composites and to prevent dust adhesion, cloudiness and heat aging, the combination of conventionally known additives is sufficiently satisfactory. The thing was unknown.

[0006]

The object of the present invention is to improve the moldability, which is a drawback of the conventional polypropylene composites for automobiles, and at the same time, it is excellent in the dust adhesion preventing property, the fog preventing property and the thermal oxidation stability. It is to provide a polypropylene composite material for automobiles.

[0007]

A first object of the present invention is to provide an inorganic filler-containing polypropylene composite material for automobiles, which has a weight loss onset temperature of 150 ° C. or higher, an antioxidant, and a metal inactive agent relative to 100 parts by weight of crystalline polypropylene. 0.01 to 10 parts by weight of each of the agent and hydrotalcite, and 0.01 to 0.01% of metal carbonate surface-treated with a fatty acid having 8 to 28 carbon atoms
˜15 parts by weight is added.

The second aspect of the present invention is characterized in that 0.01 to 1 part by weight of an anionic surfactant is added to 100 parts by weight of crystalline polypropylene, in addition to the above polypropylene composite for automobiles. The polypropylene used in the present invention is a crystalline polymer of propylene homopolymer or a random or block copolymer of propylene and α-olefin such as ethylene, butene-1, hexene-1,4-methylpentene-1. ..

The specific antioxidants used in the present invention are:
It is a compound in which a reduction starting temperature of 150 ° C. or higher is used alone or in combination with a phenol-based compound, a sulfur-based compound, a phosphorus-based compound or the like. Specific examples of these compounds include tetrakis [methylene- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, 1,3,5-trimethyl-2,4,6-tris (3 , 5-di-t-butyl-
4-hydroxybenzyl) benzene, 3,9-bis [1,1-di-t-butyl-2- {β- (3-t-butyl-4-hydroxy-5-methylphenyl) propynyloxy} ethyl]- 2,4,8,10-Tetraoxysuspyro [5,5] undecane, Tris (2,4-di-t
-Butylphenyl) phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, di (2,4-di-t-butylphenyl) pentaerythl Tall-di-phosphite, tetrakis (2,4-di-t-butylphenyl)
4,4-biphenylene-di-phosphonite and the like can be mentioned. The polypropylene composite material for automobiles using the antioxidant whose weight loss onset temperature does not reach 150 ° C. causes fog after being attached to the automobile.

The metal deactivator used in the present invention is
It is an additive for preventing resin deterioration due to metal contact, metal insert, metal powder kneading, etc., with a weight loss starting temperature of 150 ° C. or higher, and its specific example is 2,2′-oxamidebis [ethyl-3- (3 , 5-di-t-butyl-4-
Hydroxyphenyl) propionate], 3- (N-salicynoyl) amino-1,2,4-triazole and the like. Among metal deactivators, the weight loss onset temperature is 1
If a material having a temperature of less than 50 ° C. is used, it may cause fogging of the molded product.

The hydrotalcite used in the present invention is a neutralizing agent for neutralizing the acidic component in the polymer,
A fine powder of hydrotalcites can be used. The hydrotalcites referred to here are hydrous basic carbonates of magnesium and aluminum, which may be natural products or synthetic products. When a higher fatty acid metal salt or the like is used as the neutralizing agent, it causes fog in the molded product.

The antioxidant, the neutralizing agent, and the metal deactivator are added in an amount of 0.01 to 2 parts by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of polypropylene.
Parts by weight. If the amount is less than 0.01 parts by weight, a sufficient effect cannot be obtained, and even if it is used in an amount exceeding 2 parts by weight, the effect is not improved and it is economically disadvantageous. Physical properties may deteriorate.

Incidentally, the weight reduction start temperature in the present invention is
Indicates the temperature when the weight of the sample is reduced by 1 wt% when heated. In the present specification, a temperature rising rate of 10 ° C. is measured with a TG / DTA300 type thermobalance manufactured by Seiko Instruments Inc.
/ Min, the value when measured at an air flow rate of 100 ml / min. As the fatty acid of the metal carbonate surface-treated with the fatty acid having 8 to 28 carbon atoms used in the present invention, lauric acid, palmitic acid, stearic acid, behenic acid, montanic acid and the like are used as the saturated fatty acid, and oleic acid is used as the unsaturated fatty acid. , Erucic acid and the like. Metal carbonate metal is Mg, C
Examples thereof include a, Sr, Ba and Zn. The surface treatment amount of the fatty acid is 10% from the viewpoint of releasing effect and cloudiness.
It is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, relative to 0 parts by weight. As the metal carbonate surface-treated with this fatty acid, a commercially available product which has been surface-treated at the same time when the product is dried can be used.

The amount of the metal carbonate surface-treated with this fatty acid is 0.01 to 100 parts by weight of polypropylene.
15 parts by weight, preferably 1 to 15 parts by weight. 0.0
If the amount is less than 1 part by weight, the releasability at the time of molding is poor and the moldability is poor. On the other hand, if the amount exceeds 15 parts by weight, the effect is not improved and it is economically disadvantageous. May cause bleeding or deterioration of physical properties.

Examples of the anionic activator used in the present invention include alkyl sulfonates having 8 to 22 carbon atoms and alkylbenzene sulfonates having 8 to 22 carbon atoms in the alkyl group. The amount added is 0.01 to 1 part by weight, preferably 0.1 for each 100 parts by weight of polypropylene.
~ 0.8 parts by weight. If the amount is less than 0.01 part by weight, the effect of preventing dust adhesion and the stability against thermal oxidation cannot be sufficiently obtained, and if the amount is more than 1.0 part by weight, the effect is not improved and it is economically disadvantageous. In addition to the above, bleeding or deterioration of physical properties may occur in some cases. In addition, among other antistatic agents, when a nonionic antistatic agent such as glycerin or amine is used, it causes bleeding and causes fogging.

An inorganic filler is added to the polypropylene composite material for automobiles of the present invention, and the addition amount is preferably 1 to 100 parts by weight, and more preferably 10 to 90 parts by weight with respect to 100 parts by weight of polypropylene. If it exceeds 100 parts by weight, the moldability is poor when the molded product is produced,
For example, even if a molded product is manufactured, the appearance of the molded product becomes poor. On the other hand, if the amount is less than 1 part by weight, mechanical properties such as rigidity, dimensional stability and heat resistance of the obtained molded article cannot be improved. Specific examples of the inorganic filler, talc, mica, clay, wollastonite, calcium carbonate, aluminum hydroxide, magnesium hydroxide, silicon dioxide, titanium dioxide, zinc oxide, magnesium oxide, zinc sulfide, barium sulfate, calcium silicate, Examples thereof include aluminum silicate, glass fiber, potassium titanate, carbon fiber, carbon black, graphite and metal fiber. Among them, talc is preferably used, and these can be used alone or as a mixture. The above-mentioned hydrotalcite used as a neutralizing agent and the metal carbonate surface-treated with fatty acid are excluded.

Further, in the present invention, other additives such as stabilizers, pigments, nucleating agents,
Lubricants and the like can be added. The composite material of the present invention includes a single-screw extruder, a twin-screw extruder, a Banbury mixer, a roll,
It can be obtained by kneading in a heat-melted state using an ordinary kneader such as Brabender or kneader.

The polypropylene composite material of the present invention is excellent in moldability such as releasability as shown in Examples described later, and automobile molded products (meter case etc.) obtained from the polypropylene composite material are extremely excellent. It has anti-dust and anti-fogging properties and thermo-oxidative stability.

[0019]

[Examples] The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The test methods for releasability, dust adhesion, cloudiness and thermo-oxidative stability in Examples and Comparative Examples are as follows. (Releasability) 110 mm length x 230 mm width x 120 mm height x 2 mm thickness box-molded product is injection-molded, and air pressure is 2.0 for release.
It was carried out at kg / cm ² . (Dust adhesion) Specimen size 150mm × 150mm × 2mm
The plate was subjected to an ash adhesion test 1 hour after being molded. (Fog test method) Put three molded products with test piece dimensions of 50 mm x 25 mm x 2 mm into a glass test tube with an inner diameter of 35 mm x a length of 350 mm, attach a glass plate to the opening, and then test by Toyo Seiki Co., Ltd. Treatment was carried out at 140 ° C. for 72 hours in a tube aging tester. The test tube taken out was allowed to cool for 10 minutes, then the glass plate was removed, and the cloudy part was subjected to a visual test. (Thermal Oxidation Stability) Evaluation was carried out in accordance with JIS K-7212 [General heat aging test method for thermoplastics (oven method)]. It measured at 150 degreeC using the gear oven by Toyo Seiki Co., Ltd. Then, the time (GO life) until the test piece (plate having a thickness of 1 mm) is completely deteriorated, in other words, the tensile strength becomes zero, was measured. Example 1 Crystalline polypropylene polymer (melt flow rate:
6.0 g / 10 min) powder 100 parts by weight, tetrakis [methylene- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane having a weight loss starting temperature of 217 ° C. 0.1 parts by weight of tetrakis (2,4-di-t-butylphenyl) 4,4-biphenylene-di-phosphonite having a weight loss starting temperature of 159 ° C. as an antioxidant and hydrotalcite. 0.05 parts by weight, 0.10 parts by weight of 3- (N-salicynoyl) amino-1,2,4-triazole as a metal deactivator having a weight loss starting temperature of 168 ° C., and 60 parts by weight of talc as an inorganic filler. 5 parts by weight of calcium carbonate surface-treated with 3% stearic acid (manufactured by Shiraishi Industry Co., Ltd., Star Bigot 15A) and alkylsulfur as an anionic surfactant. After mixing the phosphate sodium 0.6 parts by weight, was performed pelleted by an extruder at 250 ° C.. The pellet temperature is 250 ℃, the mold temperature is 50 ℃
Was injection molded into a box-shaped molded product and a plate having a thickness of 2 mm.

When the box-shaped molded product is molded, the mold releasability is tested,
The resulting plates were tested for dust adhesion and haze and the results are shown in Table 1. Examples 2 and 3 The procedure of Example 1 was repeated, except that the amounts of calcium carbonate surface-treated with 3% stearic acid shown in Table 1 were changed to 8 and 12%, respectively. The results are shown in Table 1. Comparative Examples 1 and 2 The procedure of Example 1 was repeated except that the addition amount of calcium carbonate surface-treated with 3% stearic acid shown in Table 1 was changed. The results are shown in Table 1. Comparative Examples 3 to 4 The procedure of Example 1 was repeated, except that the compounding recipes shown in Table 1 were used. The results are shown in Table 1. Comparative Example 5 Example 2 except that the anionic activator shown in Table 1 was omitted.
I went the same way. The results are shown in Table 1.

[0021]

[Table 1]

As shown in the table above, 5 to 12 parts by weight of calcium carbonate surface-treated with 3% stearic acid and 0.6 parts by weight of anionic surfactant were added in addition to the antioxidant and the metal deactivator. It can be seen that the added inorganic filler-containing polypropylene composite material is excellent in mold releasability, cloudiness, dust adhesion and thermal oxidation stability.

[0023]

EFFECT OF THE INVENTION The polypropylene composite material of the present invention is excellent in molding processability, and molded articles for automobiles obtained from the polypropylene composite material have extremely excellent dust adhesion preventing property, anti-fogging property and thermal oxidation stability. is doing. The composite material of the present invention is particularly suitable as a material for an automobile meter case.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location C08K 5/36 KFD 7167-4J 5/42 KFG 7167-4J 5/524 KFM 7167-4J 9/04 KFU 7167-4J C08L 53/00 LLV 7142-4J LLW 7142-4J

Claims (2)

[Claims] 1. In an inorganic filler-containing polypropylene composite material for automobiles, 0.01 parts of an antioxidant, a metal deactivator, and hydrotalcite each having a weight loss onset temperature of 150 ° C. or higher are added to 100 parts by weight of crystalline polypropylene. -10
A polypropylene composite material for automobiles, characterized in that 0.01 to 15 parts by weight of a metal carbonate surface-treated with a fatty acid having 8 to 28 carbon atoms is added. 2. The polypropylene composite for automobiles according to claim 1, further comprising 0.01 to 1 part by weight of an anionic surfactant with respect to 100 parts by weight of crystalline polypropylene. Material.