JPH02296856A - Filler-reinforced propylene resin composition - Google Patents

Abstract

PURPOSE:To provide the title composition excellent in rigidity, low-temperature impact resistance, etc., by mixing a specified propylene/ethylene block copolymer with an ethylene/propylene/butene-1 copolymer rubber and a filler in a specified weight ratio. CONSTITUTION:A filler-reinforced propylene resin composition is produced by mixing 30-94wt.% amorphous propylene/ethylene block copolymer of an ethylene content of 2-20wt.%, a room temperature xylene-soluble content of 3-35wt.% and an MFR of 2-100g/10min with 35-1wt.% ethylene/propylene/butene-1 copolymer rubber of a propylene content and a butene-1 content of 20-55wt.% and 3-15wt.%, respectively, and having an MFR (at 230 deg.C under a load of 2.16kg) of 0.5-25g/10min and a degree of crystallization <=5%, and 35-5wt.% filler (e.g. talc or glass fiber).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a filler-reinforced propylene resin composition,
The present invention relates to a filler-reinforced propylene resin composition that has an excellent balance between rigidity and low-temperature impact strength, particularly good dimensional accuracy and surface hardness of molded products, and excellent kneading workability.

[Conventional technology]

Conventionally, filler-reinforced propylene resin has excellent strength, heat resistance, moldability, chemical resistance, etc., and is also economical, so it has been used in various industrial parts fields, such as home appliance parts,
It is widely used in the fields of automobile parts, building materials, etc. Also,
In particular, in many cases, attempts have been made to add various rubber components to impart the high low-temperature impact strength required for some home appliance parts and automobile parts. The types of rubber components include ethylene/propylene copolymer rubber, styrene/propylene copolymer rubber,
Butadiene copolymer rubber, isoprene rubber, styrene,
Butadiene-styrene block copolymers and their hydrogenated products are available. Among these, ethylene-propylene copolymer rubber is often put to practical use due to its balance of durability, impact strength level, dispersibility, appearance, economical efficiency, etc.

However, in order to impart sufficient low-temperature impact strength to these compositions, it is necessary to add a large amount of
In this case, the dimensional accuracy of the molded product will be relatively good, but
It has the disadvantage that the rigidity and surface hardness are significantly deteriorated, and that the important cryogenic strength and dimensional accuracy are lowered in the addition amount range where these can be maintained at a good level.

Various attempts have been made to improve this balance; for example, there is a method of adjusting the constituents of ethylene-propylene copolymer rubber. That is, by increasing or decreasing the ethylene component of the copolymer rubber, for example, if the ethylene component is decreased (that is, the propylene component is increased), the low-temperature impact strength of the filler-reinforced propylene resin composition to which these are added will be significantly improved. , dimensional accuracy is also improved (that is, mold shrinkage is reduced and mold fidelity is improved).

However, in this case, the surface hardness of the molded product decreases significantly, making it difficult to put it into practical use. At the same time, the shape retention of this copolymer rubber at room temperature is significantly deteriorated, and its surface tackiness also increases, making it virtually difficult to knead it with other fillers and the like. Of course, if the propylene resin and the rubber are kneaded in advance and made into pellets, the kneading operation becomes possible, but as a matter of course, the cost increases accordingly, which is not preferable.

Furthermore, if the ethylene content is increased, the rubbery properties will be lost, making it difficult to impart low-temperature impact strength and improve dimensional accuracy, making it difficult to put it to practical use.

[Problem to be solved by the invention]

The present inventor has developed a filler that not only has a good balance between rigidity and low-temperature impact strength, but also has excellent mold fidelity and surface hardness of molded products during injection molding, as well as excellent kneading workability and economic efficiency during production. We have conducted repeated research with the aim of providing a reinforced propylene resin composition.

[Means to solve the problem]

As a result, it was discovered that the above objective could be achieved by combining a specific propylene/ethylene block copolymer; a specific ethylene/propylene/butene-1 copolymer rubber; and a filler. Completed the invention. That is, the present invention provides the following (a) to (c)
) components, and the blending amount of each component is (al 30 ~
94% by weight, fb) l ~35% by weight, (c) 5-3
5% by weight of a filler-reinforced propylene resin composition.

(Al ethylene content is 2 to 20% by weight, substantially amorphous room temperature xylene soluble content is 3 to 35% by weight, and MFR (230°C, 2.16 kg load) is 2 to 1
00g/10min Propylene/ethylene block copolymer (b) Consists of ethylene, propylene, and butene-1, with a total content of propylene and butene-1 of 2 each.
0 to 55, 3 to 15% by weight, and M F R (2
30℃, 2.16kg load) is 0.5-25g/10
Ethylene-propylene-butene-1 copolymer rubber (c) filler having a crystallinity of 5% or less by X-ray diffraction.Here, each component used in the composition of the present invention will be described in detail.

(a) Propylene/ethylene block copolymer The (a) component propylene/ethylene block copolymer resin used in the present invention has an ethylene content of 2 to 20% by weight, preferably 4 to 20% by weight, and substantially It is essentially amorphous and contains 3 to 35 weight percent, preferably 5 to 30 weight percent, of xylene soluble matter at room temperature. Here, the ethylene content is a value measured by a conventional method such as infrared spectroscopy or NMR method, and the xylene soluble content at room temperature is
This value is back-calculated from the solid phase weight obtained by immersing 2 g of a sample in 500 g of boiling xylene for 5 hours to dissolve it, cooling it to room temperature, filtering the precipitated solid phase with a 64-type glass filter, and drying it. .

In addition, this copolymer must be resin-like, and JIS
-7210 (230"c, 2.16kg load) 2~100g/10 minutes, preferably 2
~50g/10 minutes, more preferably 2-30g/10
Minutes are practical. In addition, it is desirable that the tactical index (1,1,) is 70 or more, preferably 80 or more, particularly 90 or more.

Copolymer resins whose ethylene content and room-temperature xylene soluble content are less than the above ranges will have poor impact resistance when made into molded products of the present invention, while those exceeding the above ranges will have poor impact resistance.
The molded body lacks rigidity.

The higher the ethylene content and xylene soluble content at room temperature, the greater the degree of improvement in impact resistance, so the desired result can be obtained by adjusting the ethylene content and xylene soluble content at room temperature within the above ranges. .

A common stereoregular catalyst is used in the production of this copolymer resin. Typically, there is a composite catalyst of a halogenated titanium compound or a supported titanium catalyst component and a halogenated organoaluminium compound, and if necessary, an electron-donating compound such as benzoic acid may be added, or by means such as co-pulverization. The zero-polymerization method that allows the use of activated products is as follows:
Special Publications No. 39-1836, No. 44-16668, No. 49-
30264 and the method described in Japanese Unexamined Patent Publication No. 5011529 is used.

This propylene/ethylene block copolymer resin may contain other unsaturated monomers [for example, butene-1, hexene-1, octene-1,4] to the extent that the effects of the present invention are not significantly impaired.
-Ternary or higher copolymers containing α-olefins such as methylpentene-1; vinyl esters such as vinyl acetate; unsaturated organic acids such as (meth)acrylic acid (ester), maleic anhydride, or derivatives thereof, etc.) Union (graft type,
It may be either a random type or a block type), or a mixture thereof.

Incidentally, propylene homopolymer and propylene/ethylene random copolymer are not preferable because the physical property balance of the composition, such as impact strength and rigidity, is poor. If component la) is less than 30% by weight of the entire composition of the present invention, moldability will be poor, and if it exceeds 94% by weight, the balance of physical properties and dimensional accuracy will be poor, making each of them unsuitable.

1) Ethylene-propylene-butene-1 copolymer rubber Next, component (b) used in the present invention, ethylene-propylene-butene-1
Butene-1 copolymer rubber consists of propylene and butene-1
The total content in weight% is 20 to 55, preferably 25 to 50, and 3 to 15, preferably 5 to 1.
2, and its M F R (230°C, 2.16
kg load) is 0.5-25g/10 minutes, preferably 1-25g/10 minutes
20g/10 minutes.

Here, the content of each component is a value measured by a conventional method such as infrared spectrum analysis or NMR. The rubber is preferably substantially amorphous, but may have some crystallinity; in this case, the degree of crystallinity should be 5% or less, preferably 4% or less, particularly 3% or less. The degree of crystallinity, which is preferable in terms of the effects of the present invention, is measured by X-ray diffraction. This rubber is often provided in the form of pellets, but crumbs or bales may also be used as long as they do not interfere with kneading workability.

The method for producing the present rubber is not particularly limited, and the present rubber may be subjected to addition polymerization of other comonomers in addition to the above-mentioned three components as long as this does not impede the effects of the present invention. Furthermore, within the scope of the present invention, two or more rubber components with different component ratios may be used in combination, and other rubber components such as ethylene/propylene copolymer rubber, ethylene/butene copolymer rubber, various It is also possible to use it in combination with styrene rubber or its hydrogenated product. Among these, in many cases, the combination with ethylene/propylene copolymer rubber improves the balance of physical properties, economic efficiency, etc. Here, the propylene content is 20% by weight
If the butene-1 content is less than 3% by weight, there is almost no improvement in physical property balance or mold fidelity (dimensional accuracy), and if the propylene content exceeds 55% by weight or If the butene content exceeds 15% by weight, the balance of physical properties and the surface hardness of the molded product will be significantly lowered, making them unsuitable.

Furthermore, those with an MFR of less than 0.5 g/10 minutes are inferior in moldability and appearance, and those with an MFR of more than 25 g/10 minutes are unsuitable because of poor physical property balance and kneading workability (surface stickiness).

Furthermore, if the content of the component (i) is less than 1% by weight of the entire composition of the present invention, the balance of physical properties and dimensional accuracy will be poor, and if it exceeds 35% by weight, the rigidity and surface hardness will be poor, making each composition unsuitable.

(c) Filler Furthermore, the filler used in the present invention (c1 component filler is
Fibers, whiskers, flakes or powders of talc, glass, mica, calcium carbonate, barium sulfate, potassium titanate, magnesium sulfate, calcium silicate, polyamide and the like are suitable. Among them, talc, mica powder, potassium titanate, magnesium sulfate whiskers, and glass fiber are particularly preferred, and talc is most preferred.

The filler may be surface-treated in advance or may be left untreated. Surface treatments include chemical or physical treatments using various treatment agents such as silane coupling agents, higher fatty acids, fatty acid metal salts, unsaturated organic acids, organic titanates, resin acids, and polyethylene glycols. One example is surface treatment. In addition to the effects of the present invention, surface treatment is effective in improving weld strength, paintability, moldability, etc.

Here, talc has an average particle diameter of 0.2 to 10 µm, preferably 0.2 to 5 µm, and mica has an average particle diameter of 1 to 150 µm, preferably 2 to 80 µm.

The method for producing these talc and mica is not particularly limited (for example, they are produced by the following method.

In other words, the rough stone is crushed using equipment such as a tube mill type crusher, an impact type crusher, a micron mill type crusher, a centrifugal roller type Imond mill, etc., and if fine crushing is required, a micron mill, a 7-tooth mill, etc. Dry or wet pulverization is carried out using a mold pulverizer, jet-o-mizer, micronizer, jesotobalberizer, stirring mill (tower mill), vibration mill, colloid mill, etc.

Next, these crushed talc and mica are passed through a cyclone,
Multilon, Micron Separator, Microbrex, Cyclone Air Separator Ultra Separator,
Equipment such as jet clones, tarashi flons, rake classifiers, hydrocyclones, hydraulic classifiers, centrifugal classifiers, etc.
Dry or wet classification is repeated one or more times to adjust its physical properties.

Among them, talc has a specific surface area of 30.000c+j/
g or more and the particle size distribution is 95% if the particle size is less than lOμ
Above, it is preferable that 85% or more is 5 μ or less, and 5 to 70% is 1 μ or less, and more preferably, the specific surface area is 35.0
OOCIII/g or more, average particle size 0.3-2.5
μ, the particle size distribution is substantially all 15 μ or less, 97% or more of 10 μ or less, 87% or more of 5 μ or less, and 5 to 70% of 1 μ or less. If the composition does not fall within the above range, the dimensional stability of the composition will be poor, and the rigidity-low-temperature impact balance, paintability, and appearance will be poor, which is not preferable.

The average particle size is measured by a light transmission method using a liquid phase sedimentation method.
- There are CP type and SKN type manufactured by Seishin Enterprises. The same measuring device is also used for particle size distribution. On the other hand, the specific surface area is measured using a constant pressure aeration type specific surface area determination apparatus, such as powder specific surface area measuring apparatus S and S-100 manufactured by Shimabara Seisakusho, based on the so-called air permeation method, which is a conventional method.

In addition, the average value of the aspect ratio, which indicates the ratio of either the vertical or horizontal length and thickness of this talc, is preferably 3 or more,
Especially 4 or more is good. Similarly, the average aspect ratio of mica is preferably 5 or more, particularly 8 or more.

In addition, if anything, it is preferable to use dry-classified talc and wet-classify mica. Note that, as mica, so-called white mica (muscovite) is more preferable than gold mica (phlogopite).

Next, the glass fibers used in the present invention have an average diameter of 15 μm.
Below, preferably 2-14μ, particularly preferably 5-14μ
11μ, and the final adhesion amount of the sizing agent (this includes a sizing component for the purpose of so-called sizing and a surface treatment component for the purpose of adhesion and compatibility with the resin) after dry finishing is 0. .01 to 0.3% by weight.

The length of the glass fiber is not specified, so the shape may be roving, chopped strand, strand, etc., but from the viewpoint of ease of mixing with propylene/ethylene block polymer etc. I prefer chopped strands. In this case, the number of convergence is usually 100~s
, ooo books are preferred, and 500 to 2,000 books are particularly preferred.

The average diameter was observed using an electron microscope, etc., and
The amount of sizing agent deposited is a value measured as a loss on ignition, and the specific sintering conditions are 600° C. and 60 m1n.

Although the glass fiber sizing agent may not contain a surface treatment component, it is usually preferable to include a coupling agent such as a silane type, an acrylic acid type, or a titanium type.

Among these, those containing aminosilane and epoxysilane camping agents are preferred.

Further, the diameter of the whiskers is preferably 2μ or less, preferably 1μ or less, and particularly preferably 0.8μ or less. The length thereof is preferably 5 μ or more, particularly 10 μ or more.

In addition, when using glass fiber, it is preferable to use, as component (a), acrylic acid partially or completely modified with an unsaturated organic acid such as maleic anhydride.

Further, if component (c) is less than 5% by weight of the entire composition of the present invention, the rigidity and heat resistance will be insufficient, and if it exceeds 35% by weight, the appearance, moldability, and impact strength will deteriorate, making each of them unsuitable.

The composition of the present invention may contain other additional components within a range that does not significantly impair the effects of the present invention (usually less than 50% by weight of the entire composition).

Additional components include thermoplastic resins or thermosetting resins other than the component (a) used in the present invention (for example, homopolymers of α-olefins such as polypropylene and polybutene, copolymers of α-olefins, Olefin polymer resins such as copolymers of α-olefin and vinyl heptamer, unsaturated organic acid-modified olefin polymers such as maleic anhydride-modified polypropylene, nylon, polycarbonate, acrylonitrile-butadiene-styrene resins (
ABS), polystyrene, polyvinyl chloride, polyphenylene oxide, petroleum resin, phenol resin, etc.), modified or unmodified rubbers, rubber-like copolymers, or latex components other than the 1bl component used in the present invention (e.g., polybutadiene, polyisoprene, etc.) , 1.2-polybutadiene, acrylonitrile-butadiene rubber, polyisobutylene, styrene-butadiene rubber, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer), hydrogen of styrene-butadiene-styrene block copolymer Additives, hydrogenated styrene/isoprene/styrene block copolymers, and antioxidants (phenol-based, sulfur-based, etc.),
Lubricants, antistatic agents, dispersants, copper inhibitors, neutralizing agents, foaming agents, plasticizers, antifoaming agents, flame retardants, crosslinking agents, flow improvers (e.g. various peroxides), weld strength improvers (for example, various peroxides), nucleating agents, and the like. Addition of these additional components is effective for improving the physical property balance, durability, paintability, printability, scratch resistance, moldability, etc. of the molded article of the present invention.

The composition of the present invention can be produced using a conventional kneading machine such as a screw extruder, twin screw extruder, Banbury mixer, roll, Brabender plastograph, or kneader.

Normally, the compound is kneaded in an extruder or the like to form a pellet-like compound and then subjected to processing, but the propylene/ethylene block copolymer, rubber component, filler, etc. are directly fed to an injection molding machine with a kneading function and then molded. It can also be molded while being kneaded in a machine. In addition, rubber components and fillers are kneaded in advance to a high concentration to form a master bunch, which is then diluted separately with a propylene-ethylene block copolymer, etc., or a propylene-ethylene block copolymer containing rubber components, etc., and then blended and compounded. It can also be molded.

The injection molded article of the present invention obtained in this way exhibits a high balance of rigidity and low-temperature impact strength, as well as good dimensional accuracy and surface hardness, which are not found in conventional propylene resin molded articles. The kneading workability is also good.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

The evaluation items for the compositions in Examples and Comparative Examples are as follows.

■Bending elastic modulus Conforms to JIS 7203, however, the measurement atmosphere is 23°C.

■Impact strength (Izotsu with cutting notch) JIS K71
10, the measurement atmosphere was -30°C.

■Dimension performance (mold fidelity) A box-shaped specimen with a wall thickness of 31cm, a length of 120n, and a height of 50mm was injection molded, and its appearance was visually observed to see if there were any sink marks or warpage. The quality of the molding shrinkage was determined as follows.

Judgment A: There is no sinkage or warpage, and the molding shrinkage rate is 0.5% or less.

B: There is almost no shrinkage warpage, and the molding shrinkage rate is more than 0.5% and less than 0.8%.

C: Sink mark - warpage is clearly noticeable, molding shrinkage rate is 0.8
% or more.

■Surface hardness Based on JIS K1202, the scale is R.

■Kneading workability Using 2FCM, which will be described later, the workability of each component la) to (c) shown in Table 1 during kneading and granulation was determined as follows: during premixing in a mixer and in the feed section of an extruder. I judged it.

Judgment Good: Premixing and extrusion granulation can be performed without any problems.

Poor: The shape retention of the rubber component is poor, and the surface is highly sticky, making premixing and feeding to the extruder prone to unevenness.

Examples 1 to 6, Comparative Examples 1 to 7 The following (al component, (b) component, and (c) component) were mixed in a 2FCM twin-screw kneading extruder (manufactured by Kobe Co., Ltd.) in the proportions shown in Table 1. The pellets were kneaded and granulated at 200°C. Using the pellets, specimens for physical property evaluation and box-shaped specimens were molded at 240°C using a screw in-line injection molding machine (manufactured by Meiki Seisakusho) for evaluation. The results are shown in Table 1.

Fat component a-1: Contains ethylene! 8% by weight, xylene soluble at room temperature 1
1% by weight, MFR 4g/l 0 minutes, +198 propylene-ethylene block copolymer powder was added with tetrakis[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)] as an additive. propionate] methane, tris(2,4-di-t-butylphenyl)phosphite and 2-(2'-hydroxy-3'-t-butyl-
0.08% by weight of each of 5'-methylphenyl)-5-chlorobenzotriazole was blended a-3;
Modified propylene-ethylene block copolymer b-1 modified with ethylene-propylene-butene-1 copolymer rubber (crystallized degree: 2.3%) b-2 = propylene content 29% by weight, butene-1 content 11%, VFR 5g/10 min ethylene propylene
Butene-1 copolymer rubber (crystallinity: 2.1%) a-2: Ethylene content 6% by weight, room temperature xylene soluble content 1
5% by weight, MFR 15g/10 min, 1198 propylene-ethylene block copolymer powder, the same additive b-3 as above: propylene content 26% by weight, MFR 4g
/10 minute ethylene/propylene copolymer rubber b-4=butene-1 content 31% by weight, MFR6g/10 minute ethylene/butene 1 copolymer rubber b-5=propylene content 1t51% by weight, MFR5g/1
0 minute ethylene/propylene copolymer rubber b-6: Propylene content 137% by weight, MFR 4g/lO minute ethylene/propylene copolymer rubber b-6:
Propylene copolymer rubber c-1: Substantially lθμ or less, with a distribution of 99% or more of 5μ or less and 33% of 1μ or less, average particle size of 1.5μ, and specific surface area of 43.000
Talc C-2 with c+J/g and an aspect ratio of 6: diameter is 9μ, length is 3 cranes, and the amount of sizing agent attached is 0.
10% by weight of aminosilane-treated glass fiber C-3: White mica with an average particle size of 60μ [Effects of the invention] The composition of the present invention has a high balance of rigidity and low-temperature impact strength, which is not found in conventional propylene resin compositions. Expresses mold fidelity and surface sclerosis. Furthermore, the workability during production is also good.

These are the comprehensive and synergistic effects of the combination of the three components (a), (bl and (c)) used in the present invention.

The composition of the present invention is suitable for application in the field of industrial parts that require the above-mentioned properties at a high level, such as home appliance parts, automobile interior and exterior parts such as bumpers and fenders, and construction material parts.

hand Continued Neho Positive book (spontaneous) June λ2, 1999

Claims (1)

[Scope of Claims] Consists of each of the following components (a) to (c), and the blending amount of each component is (a) 30 to 94% by weight, (b) 1 to 35% by weight
, (c) 5 to 35% by weight of a filler-reinforced propylene resin composition. (a) ethylene content is 2 to 20% by weight, substantially amorphous room temperature xylene soluble content is 3 to 35% by weight, and MF
R (230℃, 2.16kg load) is 2 to 100g/1
0 minute propylene/ethylene block copolymer (b) Consists of ethylene, propylene, and butene-1, with a total content of propylene and butene-1 of 2 each.
0 to 55, 3 to 15% by weight, and MFR (230
℃, 2.16 kg load) is 0.5 to 25 g/10 minutes, and the degree of crystallinity is 5% or less by X-ray diffraction.
Propylene-butene-1 copolymer rubber (c) filler