JPS5815544A - Polyolefin composition - Google Patents

Abstract

PURPOSE:To provide a compsn. having excellent rigidity, low- temperature impact resistance, coatability and dimensional stability and suitable for bumper, by blending a crystalline olefin, an ethylene/alpha-olefin copolymer rubber, a filler and an unsaturated carboxylic acid-modified polyolefin. CONSTITUTION:7-87wt% crystalline polyolefin (i) such as a crystalline ethylene/propylene block or random copolymer, 5-50wt% ethylene/alpha-olefin copolymer rubber (ii) such as an ethylene/propylene copolymer rubber, 5-40wt% filler (iii) selected from among talc, mica, fiber and crystalline calcium silicate, and 3-50wt% modified polyolefin (iv) obtd. by modifying part or the whole of components (i) and /or (ii) with an unsaturated carboxylic acid (derivative), are kneaded together to obtain the titled compsn.

Description

[Detailed description of the invention] Concerning improvement of thermal impact resistance, square cylindrical properties, and molding dimensional accuracy.

In more detail, crystalline polyolefin,
- A polyolefin composition comprising an olefin copolymer rubber, talc, mica or fibrous crystalline calcium galate and a modified polyolefin.

Conventionally, polyolefins, such as polypropylene (1) polypropylene, have been widely used in general to industrial fields as molded products, films, fibers, etc. with various excellent physical and mechanical properties. ing. However, such polyolefins have drawbacks due to the substance itself, and their use may be limited depending on the field of use. For example, when polypropylene is used in industrial fields such as automobile parts, good dimensional accuracy, high rigidity and impact strength are required, so propylene-ethylene block copolymer or inorganic filler-reinforced polypropylene is used. is not in use. However, when combining propylene and handshake blocks, it is common to
Although the impact resistance in the vicinity does not improve, the impact resistance at low temperatures does not improve, and the decoration properties such as painting, scratching, adhesion, etc., the molding shrinkage rate, and the dimensional accuracy during molding such as warping are also low. Furthermore, when an inorganic filler is added to polypropylene, the rigidity and dimensional accuracy are improved, but there is a drawback that low-temperature impact resistance is significantly reduced and the material becomes brittle.

(2) Therefore, there has been no proposal for a composition in which a splitting strength improving agent is blended with a polyolefin. For example, 89-20% by weight of polyolefin, 1-2% by weight of synthetic rubber or natural rubber.
A thermoplastic resin composition consisting of 0 weight 11 parts and a powdered talc-based filler 1 to 20 weight 1 parts (Japanese Patent Application Laid-open No. 51-456735
(Publication), ffi containing iron 20 weights '1, hereinafter referred to as 'ruto flow index (hereinafter referred to as MT) 0.5 to 10
Crystalline Koterene-propylene block copolymer 5o~
90 weight ■ 1%, MIo, 2-10 amorphous royal hand Shin-α
-Olefin copolymer 5 to 20 times 1 layer and talc 5 to
Impact-resistant resin composition consisting of 40 layers of 1 Soame (Japanese Patent Application Laid-open No. 1986
-64257) etc. are known.

However, although impact resistance has been improved in these prior art techniques, rigidity, low W+rt impact resistance, paintability, dimensional accuracy during molding, weld strength, etc. are not necessarily sufficient.

The present inventors have conducted various studies on methods for modifying polyolefins in order to further improve such properties. [By blending a polyolefin modified with an unsaturated carboxylic acid or its derivative into a composition consisting of a crystalline calcium silicate filler, impact resistance, street decoration properties, and They discovered that dimensional accuracy during molding, weld strength, etc. can be further improved.

That is, the present invention provides (1+solidifying polyolefin, (2
) Ote Shin-α-olefin copolymer copolymer co-A, +a+crystalline polyolefin (1) and/or 1,000 Shin-α-olefin copolymer rubber (2) partially or entirely with unsaturated carboxylic acid or its Modified polyolefin modified with a derivative, and (4) talc and mica coating m
The present invention provides a polyolefin composition comprising fibrocrystalline calcium silicate, and includes the following cases. That is, (a) (I) a crystalline polyolefin modified with an unsaturated carboxylic acid or its derivative;
- a polyolefin composition consisting of an olefin copolymer rubber and (3) talc, mica or fibrous crystalline calcium silicate; (b) (+l crystalline polyolefin; (2) 1 modified with an unsaturated carboxylic acid or a derivative thereof; Chishin α-
A polyolefin composition comprising an olefin copolymer rubber and (3) talc, mica mapped fiber crystalline calcium silicate, (c) a crystalline polyolefin modified with a full unsaturated carboxylic acid or a derivative thereof, (2+ A polyolefin composition consisting of a Koteren-α-olefin copolymer rubber modified with a saturated carboxylic acid maple derivative, (3) talc, mica or fibrous crystalline calcium gaoxide, and (d) (11 crystal fl. Polyolefin, (2) 1,000-shin-α-olefin copolymer rubber, (3
A polyolefin composition comprising:) a polyolefin modified with an unsaturated carboxylic acid or a derivative thereof; and (4) talc, mica or fibrous crystalline calcium silicate.

The crystalline polyolefins used in the present invention include low density polyethylene (hereinafter referred to as LDPE), linear low density polyethylene (hereinafter referred to as L-Ll), medium density polyethylene (hereinafter referred to as L-Ll),
MDPE), high density polyethylene (HDP)
E) , polypropylene, poly-1-butene, poly-4
-'7,000-ru-1-pentene, Outeshin-propylene block or random copolymer, Outerene-1-butene copolymer, propylene-1-butene copolymer, Outeshin-vinyl acetate copolymer, and mixtures thereof. I can't give you anything like that. The content of Oteshin in Konera is 20ffi @1
The following crystalline 1,000-thick-propylene block or random copolymers are particularly preferred.

And these polyolefin uMI0.5~50ri7
A 10 minute test is used.

The 1,000-silicon-α-olefin copolymer rubber used in the present invention is a copolymer rubber of olefin and α-olefin, such as propylene, 1-butene, 1-hegycene, or the like. Examples include terpolymer gono\ (hereinafter referred to as EpD+, x), which is obtained by copolymerizing a propylene system with a non-conjugated diene as a third component, such as odoridennorbornene and dicyclopentadiene. Konera's Uchite is Ouderen-brobylene copolymer comb (hereinafter referred to as E P
R), straddle F PDM is preferred. These Outeshin-α-olefin copolymer rubbers are manufactured by one Outeshin-containing company with a Mooney viscosity of 20 to 90, and a Mooney viscosity (JIS
K, -6300M'Li+,'l 100°C or less) is 10 to 120, 11.

In the present invention, the polyolefin modified with an unsaturated carboxylic acid or a derivative thereof is the above-mentioned crystalline polyolefin-covered-alpha-olefin copolymer rubber. Preferred examples of the crystalline polyolefin α-olefin copolymer rubber include LDP E, HDPE, propylene, and egg sulfate content with an iT content of 20% or less. Block or random copolymer of propylene, EPR
Examples of unsaturated carboxylic acids used for modifying crystalline polyolefin copolymer rubbers include EPDM, 1-butene-1-butene rubber, etc. Acid, methacrylic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, endo-Pcyclo 2.z, 1) -1,4,
5,6,7,7-hexachloro-5-hebutene-2,6
Dicarboxylic acid, endo-pycyclo(2,2,1)
-s-hebutene-2,5-dicarboxylic acid, cis-4-cyclohexene-1,2-dicarboxylic acid, and the like.

In addition, examples of derivatives of unsaturated cartonic acid include acid anhydrides and esters, such as maleic anhydride, citraconic anhydride, endobicyclo-[2,2,1]-1,4
,5,6,7,7-hexachloro-5-hebutene-2,
5 Dicarphonic anhydride, Endo-Pcyclo(2,,
2,1) -s-hebutene-2,5 dicarboxylic anhydride,
cis-4-cyclohexene-1,2 anhodicarboxylic acid,
Methyl acrylate, methyl methacrylate, methacrylate, methacrylate, butyl acrylate, butyl methacrylate, maleic esters (monoesters, diesters), and the like can be mentioned. Among these unsaturated carboxylic acids or derivatives thereof, endo-pycyclo(2,
Preference is given to using 2,1:]-5 to hebutene-2,5 dicarboxylic anhydride or maleic anhydride.

In order to modify the polyolefin-coated α-olefin copolymer rubber, a known method can be employed. For example, it can be produced by heating a polyolefin and an unsaturated carboxylic acid or a derivative thereof in the presence or absence of a solvent, with or without the addition of a reaction initiator.

Here, the weight ratio of the unsaturated carboxylic acid or its derivative to be added to the polyolefin is preferably 1 to 3.

The talcum filler used in the present invention has an average particle size of 0.
Mica has an aspect ratio of 5 to 10 with an average particle diameter of 1 to 200 μ and an aspect ratio of 10 to 100. (9) Fiber crystalline calcium silicate has an average particle size of 1 to 100
Examples include those having μ and an aspect ratio of 5 to 50. Among these, those with a high aspect ratio are preferred, and those with an aspect ratio of 5 or more are particularly preferred.

The combination of this high aspect ratio filler is
- Effective for preventing a decrease in rigidity due to blending of olefin copolymer rubber. These fillers may or may not be surface-treated with silane or a titanium coupling agent, but better results will be obtained if surface-treated.

In addition, the characteristics of the composition due to the combination of these fillers are as follows:
In addition to improving impact resistance, it also improves the film peel strength for talc, the flexural modulus for mica, the dimensional accuracy during molding, the film peel strength, and the film peel strength for fibrous crystalline calcium silicate. It is particularly excellent in improving weld strength and the like.

Particularly preferable blending ratios of each tS contained in the composition of the present invention are crystalline polyolefin 7 to E17% by weight, Oteshin-α-olefin copolymer (10) body rubber 5 to 50J1￥a%, modified polyolefin 5 ~5
It consists of 0 market volume section, and 5 to 40 charge section.

In the phase 2 mentioned above, if the amount of Oudelene-α-olefin copolymer rubber is less than 5 times, the impact resistance strength and prismatic cylindrical properties will be improved! On the other hand, if the modified polyolefin is less than 50%, the moldability is poor due to a decrease in the resin softening temperature, and the rigidity is also reduced.Next, if the modified polyolefin is less than 6%, the rigidity and impact resistance There is no effect of further improving the elasticity, rolling properties, and dimensional accuracy during molding.On the other hand, if the weight coefficient exceeds 50, there is no promoting effect, and conversely, the bending modulus of elasticity decreases, which is undesirable. If it is less than 5% by weight, molding shrinkage, dimensional accuracy such as warping, and rigidity during molding will not be improved, while if it exceeds 40% by weight, molding process 11: will be deteriorated.

As a method for producing the composition of the present invention, each component of a crystalline polyolefin, a modified polyolefin, an Otteshin-α-olefin copolymer rubber, and a filler (for example, Henschelmigisser, (11)) is used. Pre-mix using a high-speed mixer, etc., and transfer this mixture to Bamba IJ.
- Examples include kneading in a heated molten state using a kneader such as a mixer, roll, or twin-screw extruder, but the method is not necessarily limited to this method.

In other words, when mixing and kneading each component, additives such as antioxidants, stabilizers such as ultraviolet absorbers, lubricants, anti-banding agents, pigments, etc. can be added.

As described above, the polyolefin composition of the present invention has excellent molding processability in injection molding, and can be easily released from a mold, and can also be extruded or blow-molded. The resulting molded product has excellent low-temperature impact resistance, rotational performance (painting, plating, etc.), and dimensional stability, and has little warping or sink marks, so it can be used in various fields, but is particularly suitable for automobile bumpers. It is.

The present invention will be explained in more detail below using Examples. In addition, the percentage of each component in the examples indicates the weight, and the test method is as follows.

fl+M: [A, STM D-1258 (2)
Bending modulus A, STM D-790 (12) (3) Izots forward I impact strength ASTM D-
2'563, 2 mm thick test piece, Notsusenku (4) Molding shrinkage rate After molding, a sheet of 550 x 100 x 5 mm was left in a constant temperature room at 20° C. for 24 hours and measured.

(5) Peeling strength of paint film A sheet of 70 x 120 x 5 mm is molded, degreased, and painted using a conventional method using a polypropylene brimer and urethane top paint. Using a testing machine, it was peeled off at 180° in a width of 10 mm, and the strength obtained was defined as the peel strength.

(6) Warping A disk with a diameter of 150mm and a thickness of 15n1m was formed using a center direct gate, and after being left for 24 hours, it was placed on a flat plate and the deformed height from the flat plate was warped.

(7) Weld strength retention rate A No. 1 tensile test piece according to ASTM D-638 is injection molded from both ends in the longitudinal direction using side gates. The obtained test piece was AS'rMD-
A tensile test (13) was performed using 65B, and the strength obtained was defined as the weld strength.

Example 1 Polypropylene homopolymer-propylene blank copolymer (MI=10
, 100 parts by weight of endo-bicyclo-(2,2.1)-5-hebutene-2,
1 part by weight of 3-dicarboxylic anhydride (hereinafter referred to as hymic anhydride) and 2,000 ruou of 2,5-dime.

5-G (Tarja Leap 1000 Ruberoxy) Hexyne-
Add 0.5 overlapping parts of 5 and premix at room temperature, feed the mixture to an extruder, melt knead at 250'C and extrude Modified polypropylene (hereinafter referred to as modified PP-1). Polymer (hereinafter modified pp-
It) was obtained. The content of Himic acid is 1. It was 0% by weight.

Crystalline Outeshin-propylene brosok copolymer (1) (
Mnie 1s, Oterene content -7%), crystalline egg shin-propylene random copolymer (Mnie 9, Oteshin content 2%), the above anhydrous Himic, acid-modified PP, HD
PE (M engineering = o3, density (14) 0.960), I-Dp +:i: (VII = 9
, density = 0.912), EPR (M-
75, Mooney viscosity -70), E T-) r+ M
(1 juice containing Oteshin = 50 parts, 3rd component = Otesu tennorboruin, Mooney viscosity 11j = 105) and talc (average particle size 40/'-, aspect ratio 5-1
0) in the combination of each experiment number shown in Table 1 and mixed with a high-speed mixer. ! ) The mixture was heated in a two-screw kneader to cylinders 4 and 11 degrees 200 to 25 degrees.
A pellet was obtained after melt-kneading at 0°C. Each test piece was molded under the cutting molding conditions of a pellet temperature of 260° C., a pressure of 900 K, and 17 cm 2 . The flexural modulus, isot impact strength, mold shrinkage rate, coating peel strength, warpage and weld strength 1 retention rate were measured for each test piece obtained, and the results are shown in Table 1 (Experiment No. 1 ~7).

For the sake of specificity, in Section 11, the physical properties of those without modified PP are also listed in Table 1. (Experiment numbers 8-11).

Example 2 As a crystalline Koterene-propylene bronc copolymer,
Copolymer (1) or copolymer (+1) (M I =
9.0, egg shin content 1=Zo%) and mica (average particle size 1DOμ, aspect ratio 10-1) instead of talc.
The table was prepared using the same material as in Example 1 except that 0 mouth) was used.
The test pieces were prepared using the combinations of experiment numbers shown in Example 2, and test pieces were molded in the same manner as in Example 1, and the physical properties were measured. The results are shown in Table 2 (Experiment No. 12-17).

For the sake of comparison, Table 2 also lists the physical properties of those without modified PP (experiment numbers 18 to 20).

Example 6 In Example 2, fibrous, crystalline calcium silicate (with an average particle diameter of 911 and an aspect ratio of 6 to 60) was used instead of mica.
The same materials were used except that the product name (trade name: WOLAST TWOIT) was used, and the mixtures were mixed according to the experiment numbers shown in Table 3, and test pieces were formed in the same manner as in Example 1 to measure each physical property. death,
The results are shown in Table 3 (experiment numbers 21 to 26).

For comparison, the physical properties of samples without modified PP are also listed in Table 6 (Experiment Nos. 27 to 29).

(19)

Claims (1)

[Claims] (1) Crystalline polyolefin, (2) 1,000-shin-α-olefin copolymer rubber, (3) Crystalline polyolefin (
1) A modified polyolefin obtained by modifying part-1 or all of the α-olefin copolymer rubber (2) with an unsaturated carboxylic acid or a derivative thereof, and (4) A polyolefin composition comprising talc, mica, or fibrous crystalline calcium galate.