JP3256995B2 - Automotive polypropylene composite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

This invention relates to automotive polypropylene composites. More specifically, the present invention relates to a polypropylene composite material for automobiles having excellent anti-fogging property and moldability, and further relates to a polypropylene composite material for automobiles having improved dust adhesion prevention property and thermal oxidation stability in addition to the above-mentioned properties.

[0002]

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

[0003] Also, while polypropylene and its composite material have excellent electrical insulation properties, it is known that they are easily charged with static electricity during molding and cause various obstacles. In addition, the molded product is extremely liable to be contaminated by dust due to electrostatic charging, and the commercial value is significantly reduced due to the strong attachment of lightning pattern stains. In the case of an automobile meter case, the attached dust causes a light quantity shortage and makes it difficult to distinguish the meter display.

[0004] Further, the polypropylene composite containing an inorganic filler has a drawback that the thermal oxidation stability is remarkably reduced as compared with a polypropylene composite containing no filler. This is considered to be because the added thermal oxidation stabilizer is inactivated by the inorganic filler. On the other hand, in order to prevent roll contamination, a sheet using an additive having a weight loss start temperature of 150 ° C. or higher (Japanese Patent Laid-Open No.
JP-A-2-132937) and 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 an alkylbenzene sulfonic acid soda 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. Conventionally, many studies have been made to improve the molding processability of such a polypropylene composite material and to prevent dust adhesion, fogging and heat aging, but the combination of conventionally known additives is sufficiently satisfactory. Things were unknown.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to improve the moldability, which is a drawback of conventional polypropylene composite materials for automobiles, and to provide excellent anti-dust, anti-fog and thermo-oxidative stability. An object of the present invention is to provide a polypropylene composite for automobiles.

[0007]

This onset Akira [Summary of], in the inorganic filler-containing polypropylene composite materials for automobiles, to crystalline polypropylene 100 parts by weight, weight loss initiation temperature of 15
0 ℃ more antioxidants, metal each from 0.01 to 10 parts by weight of deactivator and hydrotalcite, 0.01 to 15 parts by weight of metal carbonate surface treated with a fatty acid having a carbon number of 8-28, And 0.01 to 1 part by weight of an anionic surfactant .

The polypropylene used in the present invention is a homopolymer of propylene or the crystallinity of a random or block copolymer of propylene and an α-olefin such as ethylene, butene-1, hexene-1,4-methyl-pentene-1. Refers to a polymer.

The specific antioxidant used in the present invention is:
A compound such as a phenol-based compound, a sulfur-based compound, or a phosphorus-based compound having a weight-loss starting temperature of 150 ° C. or higher is used alone or in combination. Specific examples of these compounds include tetrakis [methylene- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane and 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-tetraoxyspiro [5,5] undecane, tris (2,4-di-t
-Butylphenyl) phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol-diphosphite, di (2,4-di-tert-butylphenyl) pentaerythl Tall-di-phosphite, tetrakis (2,4-di-t-butylphenyl)
4,4-biphenylene-diphosphonite and the like. A polypropylene composite for automobiles using an antioxidant whose weight loss onset temperature does not reach 150 ° C. causes clouding after being mounted on an automobile.

The metal deactivator used in the present invention includes:
It is an additive having a weight loss start temperature of 150 ° C. or more for preventing resin deterioration due to metal contact, metal insert, metal powder kneading, and the like. Specific examples thereof include 2,2′-oxamidobis [ethyl-3- (3 , 5-Di-t-butyl-4-
Hydroxyphenyl) propionate], 3- (N-salicynoyl) amino-1,2,4-triazole and the like. Among the metal deactivators, the weight loss onset temperature is 1
Use of a material having a temperature lower than 50 ° C. causes clouding of a molded product.

The hydrotalcite used in the present invention is a neutralizing agent for neutralizing acidic components in the polymer,
Hydrotalcite fine powders may be used. The hydrotalcites here are hydrous basic carbonates of magnesium and aluminum, and 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 clouding of the molded product.

The amounts of these antioxidants, neutralizers and metal deactivators are 0.01 to 2 parts by weight, preferably 0.1 to 1 part by weight, per 100 parts by weight of polypropylene.
Parts by weight. If the amount is less than 0.01 part by weight, a sufficient effect cannot be obtained. If the amount is more than 2 parts by weight, the effect is not improved and it is economically disadvantageous. The physical properties may be reduced.

In the present invention, the weight loss starting temperature is
When the sample is heated, the temperature at which the weight is reduced by 1 wt% is shown. In this specification, the temperature is raised at a rate of 10 ° C. using a TG / DTA300 type thermobalance manufactured by Seiko Electronics Industry Co., Ltd.
/ Min, and a value measured at an air flow rate of 100 ml / min. As the fatty acid of the metal carbonate surface-treated with a 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 saturated fatty acids, and oleic acid is used as an unsaturated fatty acid. And erucic acid. Metal of metal carbonate is Mg, C
a, Sr, Ba, Zn and the like. The surface treatment amount of the fatty acid is set at 10% in terms of the release effect and the haze.
It is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight based on 0 parts by weight. As the metal carbonate surface-treated with the fatty acid, a commercially available metal carbonate surface-treated at the same time as drying the product can be used.

The amount of the metal carbonate surface-treated with the 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 mold releasability at the time of molding is poor and the molding processability is inferior. 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 an alkyl sulfonate having 8 to 22 carbon atoms, and an alkylbenzene sulfonate having an alkyl group having 8 to 22 carbon atoms. The addition amount is 0.01 to 1 part by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of polypropylene.
0.8 parts by weight. If the amount is less than 0.01 part by weight, sufficient effects on dust adhesion preventing property and thermal oxidation stability cannot be obtained, and even if the amount exceeds 1.0 part by weight, the effect does not increase and it is economically disadvantageous. In addition, bleeding or deterioration of physical properties may occur in some cases. In the case where a glycerin-based or amine-based antistatic agent is used among other antistatic agents, it bleeds and causes fogging.

Although the inorganic filler is added to the polypropylene composite for automobiles of the present invention, the amount is preferably 1 to 100 parts by weight, more preferably 10 to 90 parts by weight, per 100 parts by weight of polypropylene. When the amount exceeds 100 parts by weight, moldability is poor when producing a molded product,
For example, even if a molded article is manufactured, the appearance of the molded article becomes poor. On the other hand, if it is less than 1 part by weight, it is not possible to improve the mechanical properties such as rigidity, dimensional stability and heat resistance of the obtained molded product. Specific examples of the inorganic filler include 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 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. In addition, the above-mentioned hydrotalcite used as a neutralizing agent and the metal carbonate surface-treated with a fatty acid are excluded.

In the present invention, other additives such as a stabilizer, a pigment, a nucleating agent,
A lubricant or the like can be added. The composite material of the present invention is a single-screw extruder, a twin-screw extruder, a Banbury mixer, a roll,
It is obtained by kneading in a heated and melted state using a usual kneader such as a Brabender or a kneader.

The polypropylene composite material of the present invention is excellent in moldability such as releasability, as shown in Examples described later, and molded articles for automobiles (meter cases and the like) obtained from the polypropylene composite material are extremely excellent. It has anti-dust adhesion, 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 the releasability, dust adhesion, haze, and thermal oxidation stability in Examples and Comparative Examples are as follows. (Releaseability) Injection molding of a box-shaped molded product with a length of 110 mm × width 230 mm × height 120 mm × thickness 2 mm, and release with air pressure of 2.0
The test was performed at kg / cm ² . (Dust adhesion) Specimen size 150mm x 150mm x 2mm
One hour after molding, the plate was subjected to an ash adhesion test. (Fogging test method) Put three test pieces 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 test it by Toyo Seiki Co., Ltd. The treatment was performed at 140 ° C. for 72 hours in a tube aging tester. After the test tube was taken out and allowed to cool for 10 minutes, the glass plate was removed and the cloudy portion was subjected to a visual test. (Thermal Oxidation Stability) The evaluation was performed in accordance with JIS K-7212 [General rules for heat aging test method (oven method) for thermoplastics]. The measurement was performed at 150 ° C. using a gear oven manufactured by Toyo Seiki Co., Ltd. Then, the time (GO life) until the test piece (1 mm thick plate) was completely degraded, in other words, until the tensile strength became zero was measured. Example 1 Crystalline polypropylene polymer (melt flow rate:
(6.0 g / 10 min) of powder, 100 parts by weight of tetrakis [methylene- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane having an onset weight reduction temperature of 217 ° C as an antioxidant. 0.1 part by weight of tetrakis (2,4-di-t-butylphenyl) 4,4-biphenylene-di-phosphonite having a starting weight loss 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 at a temperature of starting weight loss of 168 ° C. as a metal deactivator, and 60 parts by weight of talc as an inorganic filler 5 parts by weight of calcium carbonate (trade name: Star Bigot 15A, manufactured by Shiraishi Kogyo Co., Ltd.) surface-treated with 3% stearic acid and alkyl sulfonate as an anionic surfactant After mixing the phosphate sodium 0.6 parts by weight, was performed pelleted by an extruder at 250 ° C.. The pellets are heated at a resin temperature of 250 ° C and a mold temperature of 50 ° C.
Injection molded into a box-shaped product and a plate having a thickness of 2 mm.

The mold releasability is tested during the molding of the box-shaped molded product,
The resulting plates were tested for dust adhesion and haze and the results are shown in Table 1. Examples 2 and 3 The same procedure as in Example 1 was carried out except that the addition amounts of calcium carbonate surface-treated with 3% stearic acid shown in Table 1 were changed to 8 and 12%, respectively. Table 1 shows the results. Comparative Examples 1 and 2 The same procedure as in Example 1 was carried out except that the formulation shown in Table 1 was used. Table 1 shows the results. Comparative Example 3 Example 2 except that the anionic surfactant shown in Table 1 was omitted.
The same was done. Table 1 shows the results.

[0021]

[Table 1] (Prescription components) A: calcium carbonate surface-treated with stearic acid B: calcium hydroxide surface-treated with oleic acid C: magnesium hydroxide surface-treated with stearic acid E: sodium alkyl sulfonate (anionic surfactant) talc: micron white 5000S (manufactured by Hayashi Chemicals, trade name) (determined) ○: good △: somewhat poor ×: poor

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

[0023]

Industrial Applicability The polypropylene composite of the present invention has excellent moldability, and a molded article for automobiles obtained from the polypropylene composite has extremely excellent anti-dust property, anti-fogging property and thermo-oxidative stability. are doing. The composite material of the present invention is particularly suitable as a material for an automobile meter case.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 23/00-23/36 C08K 3/00-13/08

Claims (1)

(57) [Claims] 1. An inorganic filler-containing polypropylene composite material for automobiles, wherein an antioxidant, a metal deactivator and hydrotalcite having a weight loss start temperature of 150 ° C. or more are added to 0.01 part by weight of crystalline polypropylene per 100 parts by weight. -10
Parts, 0.01 to 15 parts by weight of metal carbonate surface treated with a fatty acid having a carbon number of 8 to 28, and anionic surface active
A polypropylene composite for automobiles, characterized by adding 0.01 to 1 part by weight of a surfactant.