JPH1160826A - Powdery resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition having good moldability such as powder flow and can give products having high flexibility and excellent mechanical properties and scratch resistance and not suffering from stickiness and fogging caused by a plasticizer by blending a polyolefin polymer with a hydrogenated polymer made from a conjugated diene copolymer of a specified vinyl bond content and having a specified degree of hydrogenation in a specified ratio. SOLUTION: Twenty to eighty wt.% polyolefin polymer is blended with 80-20 wt.% hydrogenated diene polymer made by saturating at least 80% of the double bonds of the conjugated diene part of a conjugated diene copolymer of a vinyl bond content of 60 wt.% or above. The polyolefin polymer is a crystalline resin of a monoolefin and is desirably polyethylene, polypropylene or polybutene-1. The hydrogenated diene polymer is exemplified by a homopolymer of a conjugated diene, a random copolymer of a conjugated diene with an aromatic vinyl compound or a product of hydrogenation of a block copolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder resin composition used for powder molding, and more particularly, to powder molding such as a fluid immersion method, an electrostatic coating method, a powder spraying method, a powder rotational molding method, and a powder slush molding method. The present invention relates to a powdered resin composition used for the present invention.

[0002]

2. Description of the Related Art Conventionally, as a powder molding method using a soft powder material, a powder slush molding method using a soft vinyl chloride resin powder has been applied to the skin of automobile interior parts such as instrument panels, console boxes, and door trims. Widely adopted. This is a soft touch, and can be provided with leather grain and stitches, and has good design properties such as a large degree of freedom in design. However, such a soft vinyl chloride resin is not only inferior in lightness, but also generates an acidic substance due to vinyl chloride when incinerated after use, and thus has a problem on environmental hygiene. As a solution to such a problem, a molded article composed of an olefin-based thermoplastic elastomer has already been proposed. As a method for producing such a molded article, a thermoplastic elastomer powder composed of an olefin-based thermoplastic elastomer having specific physical properties has been proposed. Has also been proposed (Japanese Patent Application Laid-Open Nos. 5-1183, 5-5050, and 5-70601). However,
Such a thermoplastic elastomer powder is not only inferior in scratch resistance but also has insufficient powder fluidity, so that a molded article having a complicated shape, such as a molded article having a narrow and high convex portion, is produced by a slush molding method. In such a case, a pinhole or underfilling tends to occur at the edge of the projection. Also,
If a plasticizer or a softening agent is added in order to make the powder flowability sufficient, stickiness or fogging may occur.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned conventional technical problems, and has high flexibility by blending a polyolefin polymer and a hydrogenated diene polymer having a specific structure. An object of the present invention is to provide a powdery resin composition which is excellent in mechanical properties and scratch resistance, does not cause stickiness or fogging due to a plasticizer or the like, and has good molding processability such as powder fluidity.

[0004]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances. That is, the present invention relates to (a) 20 to 80% by weight of a polyolefin polymer, and (b) at least 8% of double bonds of a conjugated diene portion of a conjugated diene polymer having a vinyl bond content of 60% by weight or more.
An object of the present invention is to provide a powdered resin composition containing 80 to 20% by weight of a hydrogenated diene polymer saturated with 0% (however, (a) + (b) = 100% by weight).

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The (a) polyolefin-based polymer contained in the composition of the present invention is a crystalline resin obtained by polymerizing one or more monoolefins by either a high-pressure method or a low-pressure method, preferably There are polyethylene, polypropylene and polybutene-1. The polyolefin resin may be a homopolymer or a copolymer obtained by copolymerizing another monomer as shown below.

Preferred monomers constituting the polyolefin-based polymer include, for example, ethylene (excluding when the main polymer is polyethylene), propylene (excluding when the main polymer is polypropylene), butene-
1 (except when the main polymer is polybutene-1), linear α-olefins such as pentene-1, hexene-1, heptene-1, and octene-1, 4-methylpentene-1, 2-methyl Branched α such as propene-1, 3-methylpentene-1, 5-methylhexene-1, 4-methylhexene-1, and 4,4-dimethylpentene-1
-Monocarboxylic acids such as olefins, acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, dicarboxylic acids such as citraconic acid and monoesters thereof, methyl methacrylate, methyl acrylate, ethyl acrylate, etc. Acrylic acid or methacrylic acid ester, vinyl acetate, vinyl ester of saturated carboxylic acid such as vinyl propionate, aromatic vinyl compound such as styrene, α-styrene, p-methylstyrene, maleic anhydride, itaconic anhydride, citracone anhydride Acids, acid anhydrides such as aconitic anhydride, α, β-unsaturated nitriles such as acrylonitrile and methacrylonitrile, diene monomers such as 1,4-hexadiene, dicyclopentadiene, and ethylidene norbornene, and acrylamide; Takuriruamido, such as maleimide can be used. These copolymerizable monomers may be used alone or in combination of two or more. The amount of these copolymer components is preferably 20% by weight or less, more preferably 10% by weight or less. The form of the copolymer when these are copolymerized is not particularly limited, and may be, for example, any of a random type, a block type, a graft type, and a mixed type thereof.

Preferred copolymers used as the polyolefin-based polymer include propylene-ethylene copolymer, propylene-butene-1 copolymer, and butene-1-
Ethylene copolymer, propylene-ethylene-butene-1
Copolymer, ethylene-vinyl acetate copolymer, ethylene-
Examples include an ethyl acrylate copolymer, an ethylene-ethyl methacrylate copolymer, an ethylene-methyl acrylate copolymer, an ethylene-methyl methacrylate copolymer, and an ethylene-n-butyl acrylate copolymer. These polyolefin polymers can be used alone or in combination of two or more.

The melt flow rate (MFR: temperature of 230 ° C., load 2.) of the polyolefin polymer (a) of the present invention.
16 kg) is not particularly limited in the present invention, but is preferably 10 g / 10 min or more, more preferably 20 g / 10 min or more.

(B) Examples of the hydrogenated diene polymer include a homopolymer of a conjugated diene, a random copolymer of a conjugated diene and an aromatic vinyl compound, and a polymer of an aromatic vinyl compound and a conjugated diene compound. A block copolymer composed of a united block, a block copolymer composed of a polymer block of an aromatic vinyl compound and a random copolymer block of a conjugated diene / aromatic vinyl compound, and a polymer block composed of a conjugated diene compound and a conjugated diene / aromatic A block copolymer consisting of a copolymer block of an aromatic vinyl compound, a block copolymer consisting of a polymer block of a conjugated diene compound and a tapered block in which an aromatic vinyl compound consisting of an aromatic vinyl compound and a conjugated diene gradually increases, conjugated Diene / aromatic vinyl compound random copolymer block and aromatic vinyl compound Diene-based polymers such as block copolymers composed of a tapered block composed of a conjugated diene and gradually increasing an aromatic vinyl compound, and block copolymers composed of a polymer block of a polybutadiene block having a vinyl bond of 30% by weight or less and a conjugated diene compound. A hydrogenated product (hereinafter, also referred to as a “pre-hydrogenated polymer”) is exemplified.
Further, the hydrogenated diene polymer of the present invention may be modified with a functional group, and at least one kind selected from an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group, and an epoxy group. A modified functional group having a functional group can also be used.

The ratio of the conjugated diene compound / aromatic vinyl compound constituting the pre-hydrogenated polymer is not particularly limited in the present invention, but is preferably from 95/5 to 40.
/ 60 (weight ratio, hereinafter the same), more preferably 93 /
7 to 50/50.

Here, the conjugated diene compound used for the component (b) includes 1,3-butadiene, isoprene,
2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3
-Hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene, and the like. Among them, a hydrogenated diene polymer which can be industrially used and has excellent physical properties can be used. For obtaining 1,3-butadiene, isoprene and 1,3-pentadiene are preferred,
1,3-butadiene and isoprene are particularly preferred. Examples of the aromatic vinyl compound include styrene, α-methylstyrene, p-methylstyrene, t-butylstyrene, divinylbenzene, N, N-dimethyl-p-aminoethylstyrene, N, N-diethyl-p-aminoethyl. Styrene, vinyl pyridine and the like are mentioned, and styrene and α-methylstyrene are preferred.

The pre-hydrogenated polymer may be a polymer in which a polymer molecular chain is extended or branched through a coupling residue by using a coupling agent. As the coupling agent used at this time, for example, diethyl adipate, divinylbenzene, methyldichlorosilane, silicon tetrachloride, butyltrichlorosilicon, tetrachlorotin, butyltrichlorotin, dimethylchlorosilicon, tetrachlorogermanium, 1,2- Dibromoethane, 1,4-chloromethylbenzene, bis (trichlorosilyl) ethane, epoxidized linseed oil, tolylene diisocyanate,
1,2,4-benzene triisocyanate and the like can be mentioned.

As the hydrogenated diene polymer (b) of the present invention, those obtained by hydrogenating a blend of two or more pre-hydrogenated polymers are also preferably used. In addition, 2
Blends of hydrogenated diene polymers of at least one species are also suitable as the (ii) hydrogenated diene polymer of the present invention.

The (b) hydrogenated diene polymer of the present invention is obtained by hydrogenating a polymer mainly composed of a conjugated diene compound. In the polymer, it is necessary that the double bond of the conjugated diene portion is preferably 80% or more, more preferably 90% or more, and if it is less than 80%, weather resistance and the like are undesirably reduced.

The preferred number average molecular weight of the (b) hydrogenated diene polymer of the present invention is from 10,000 to 700,000, and more preferably from 5 to 700,000.
When it is 600,000 and less than 10,000, the hydrogenated diene-based polymer is easily blocked when pelletized, and (a) when blended with the polyolefin-based polymer, the mechanical strength is reduced. If it exceeds, the fluidity, processability, molded appearance and the like become poor.

In the (b) hydrogenated diene polymer of the present invention, the proportion of vinyl bonds in the side chain derived from 1,2- and 3,4 bonds in the conjugated diene portion is at least 60% by weight, preferably at least 60% by weight. 65% by weight or more, more preferably 70% by weight
That is all. The ratio of vinyl bonds in the conjugated diene moiety is 6
If the amount is less than 0% by weight, for example, when the conjugated diene is butadiene, a large number of polyethylene chains are formed when hydrogenated,
Rubbery properties are lost and are not preferred.

The (b) hydrogenated diene polymer of the present invention is disclosed, for example, in JP-A-3-72512, page 4, upper right column, line 13 to page 6, lower left, first line, and JP-A-5-271325. Page 3, left column, line 42 to page 7, right column, line 19, JP-A-5-271
No. 327, page 3, left column, line 36 to page 7, right column, line 31.

The composition of the present invention comprises (a) a polyolefin-based polymer and (b) a hydrogenated diene-based polymer, and has high flexibility, excellent mechanical properties, excellent scratch resistance, and is caused by a plasticizer and the like. It is a composition which does not cause stickiness, fogging and the like, and has good moldability such as powder fluidity. In the composition of the present invention, the compounding ratio of (a) the polyolefin polymer and (b) the hydrogenated diene polymer is 20 to 80% by weight, preferably 20 to 70% by weight, and (B) the component. 80-2
0% by weight, preferably 80 to 30% by weight. (I)
When the content of the component is less than 20% by weight, the mechanical strength is reduced, and when the content is more than 80% by weight, the flexibility and the scratch resistance are reduced.

The powdered resin composition of the present invention can be subjected to crosslinking such as sulfur crosslinking, peroxide crosslinking, metal ion crosslinking, silane crosslinking, and resin crosslinking, if necessary, by a conventionally known method.

The production of the powdered resin composition of the present invention includes:
The method is not particularly limited, and a known method can be used. For example, various extruders, Banbury mixers,
The components obtained by kneading the components with a kneader, a roll, or the like can be made into a powder by a pulverizer such as a turbo mill, a roller mill, a ball mill, a pin mill, a hammer mill, or a centrifugal pulverizer. At this time, it may be frozen and pulverized using liquid nitrogen or the like, or may be pulverized at room temperature.

Further, using various extruders, the discharge port diameter of the die is 0.1 to 3 mm, and the discharge speed of the die is 1 to 10 mm.
For example, there is a method in which the strand is taken out at a speed of 2 to 150 m / min, which is higher than the discharge speed from the die at a speed of 0 m / min.

The powder resin composition of the present invention has an average particle size of 5
It is desirable to use it after pulverizing it to 0 to 800 μm, preferably 50 to 500 μm, and more preferably 100 to 300 μm. If the average particle size is less than 50 μm, the efficiency of the pulverizing step is poor, and if it exceeds 800 μm, the texture of the molded product becomes coarse, and in the case of a molded product having a small thickness, pinholes are easily generated, which is not preferable.

The composition using the components (a) and (b) of the present invention may optionally contain various additives such as an antioxidant,
Stabilizers such as heat stabilizers, weathering agents, metal deactivators, ultraviolet absorbers, light stabilizers, copper damage inhibitors, antibacterial and fungicide agents, dispersants, softeners, plasticizers, foaming agents, foaming aids Agent, titanium oxide,
Colorants such as carbon black, metal powders such as ferrite, inorganic fibers such as glass fibers and metal fibers, organic fibers such as carbon fibers and aramid fibers, composite fibers, inorganic whiskers such as potassium titanate whiskers, glass beads, and glass balloons , Glass flake, asbestos, mica, calcium carbonate, talc, silica, calcium silicate, hydrotalcite, kaolin, diatomaceous earth, graphite, pumice, evo powder, cotton floc, cork powder, barium sulfate, fluororesin, polymer beads Or a mixture thereof, a filler such as polyolefin wax, cellulose powder, rubber powder, and a low molecular weight polymer. Also,
A rubbery polymer, a thermoplastic resin, or the like can be appropriately blended to such an extent that the effects of the present invention are not impaired. Especially EBM
(Ethylene-butene-1 copolymer), EPM, EPD
M, EVA, an ethylene copolymer obtained by a metallocene polymerization catalyst, or the like may be blended.

[0024]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples.
However, the present invention is not limited to these examples.
Not. In Examples and Comparative Examples, parts and% are
Unless otherwise specified, it is based on weight. Examples, comparison
Various measurements in the examples were based on the following methods.Vinyl bond content such as 1,2-bond The content of 1,2-bonds and the like was determined by infrared
It was calculated by the standard method. Hydrogenation rate The hydrogenation rate of the conjugated diene is determined using ethylene tetrachloride as the solvent,
Calculated from 100 MHz, 1H-NMR spectrum.Number average molecular weight of hydrogenated diene polymer Number average molecular weight (hereinafter also referred to as “molecular weight”)
By using permeation chromatography (GPC)
It was determined in terms of polystyrene.UV absorption A hydrogenated diene-based polymer was prepared with a width of 200 × length of 300 × thickness.
After making it into a 5mm sheet, it becomes a strip of width 5 x length 50mm
It was cut, washed with distilled water and dried. This sample is pre-pressurized
Put into a 300 ml glass container sterilized with air
After adding 0 ml, sealing and extracting at 121 ° C. for 1 hour.
U. This test solution absorbs UV at a wavelength of 220 to 350 nm.
It was measured and determined according to the following criteria. ：: UV absorption is 0.1 or less ×: UV absorption exceeds 0.1Liquidity 230 ° C, load 2.1 according to JIS K7210
Measure the melt flow rate (MFR) at 6 kg,
It was used as an index of formability.Tensile properties Tensile strength and elongation of sample according to JIS K6301
Was measured.hardness Measure JIS A hardness according to JIS K6310,
Judgment was made based on the following criteria. ：: excellent in flexibility: hardness less than 80 △: flexible: hardness is 80 to 90 ×: poor in flexibility: hardness exceeds 90Mold appearance The molding appearance was visually evaluated according to the following criteria. ：: No pinholes, and good grain transferability. ×: Pinholes or underfill are present, grain transferability is poor, and gloss
There are some poor appearance phenomena such as the presence of irregularities.Scratch resistance Tabers clutch tester manufactured by Toyo Seiki Seisaku-sho, Ltd.
Using a testing machine, carry out a scratch test while changing the load.
Was. Damage the load when the surface of the sample is matt
The load was determined as follows. ：: Excellent scratch resistance: Scratched load of 100 g or more △: Scratched resistance: Scratched load of 30 to 100 g or more ×: Poor scratch resistance: Scratched load of less than 30 gFogging Place the test specimen in a special beaker with
Cover the bottom with a transparent glass plate
The mixture was heated in an oil bath at 120 ° C. for 5 hours. afterwards
Take out the transparent glass with and according to JIS K6714
The haze was measured and determined according to the following criteria. ：: Excellent fogging property: less than 5% haze ×: Poor fogging property: 5% or more haze

Various components used in the formulations shown in Examples and Comparative Examples are as follows. Polyolefin-based polymer P-1; Propylene-ethylene random copolymer manufactured by Japan Polyolefin Co., Ltd., MG970-3, MFR = 8
0 g / 10 min P-2; Propylene-ethylene block copolymer manufactured by Nippon Polychem Co., Ltd., BC05B, MFR = 50 g / 10
Min. P-3; low density polyethylene manufactured by Nippon Polychem Co., Ltd.
LJ800, MFR = 18 g / 10 min (190 ° C., 2.
16kg load)

Hydrogenated diene polymer A hydrogenated diene polymer having the structure shown in Table 1.

[0027]

[Table 1] * 1) BD: butadiene * 2) ST: styrene * 3) IP: isoprene * 4) Part A: polymer part mainly composed of aromatic vinyl compound * 5) Part C: aromatic vinyl compound and conjugated diene compound Tapered polymer part * 6) A: A part, C: C part, B: random copolymer part

Crosslinking agents X-1 to 2 X-1 (organic peroxide); Perhexin 25B-40 [manufactured by NOF CORPORATION] [2,5-dimethyl-2,5-di (t
-Butylperoxy) hexine-3] crosslinking aid Y-1 (crosslinking aid); Sankyo Kasei Co., Ltd., divinylbenzene process oil O-1 (paraffinic oil); Idemitsu Kosan Co., Ltd., Diana Process Oil PW380

Examples 1 to 10 and Comparative Examples 1 to 4 A polyolefin polymer and a hydrogenated diene polymer were mixed at 220
Using a single screw extruder set at a temperature of ° C., the mixture was mixed and pelletized at a weight ratio shown in Tables 2 and 3. The pellets were passed through a turbo mill-type pulverizer, and a 500 μm sieve was collected to obtain a powdered resin composition. Next, the powdered resin composition was heated to a temperature of 2
Electroforming mold with embossing at 50 ° C (length 1200 mm x width 500
mm) and left for 5 seconds, the mold was inverted to remove excess powder, and left as it was for 60 seconds.
Then, it cooled and was demolded, and the molded article was obtained. The thickness of the obtained molded product was 1 mm. Table 3 ~
The results are shown in FIG. From the results of Examples 1 to 8 shown in Tables 2 and 3,
It can be seen that the resin composition of the present invention is more excellent in the balance of tensile strength, fluidity, flexibility, scratch resistance and molded appearance than Comparative Examples 1 to 4 shown in Table 4. In Examples 9 to 10 shown in Table 3, a rubbery polymer together with a hydrogenated diene polymer; EP (manufactured by Nippon Synthetic Rubber Co., Ltd., EP02P);
In this case, EO [ENGAGE 8200 manufactured by Dow Chemical Co., Ltd.] is used, and it can be seen that all of them have an excellent balance of tensile strength, fluidity, flexibility, scratch resistance and molded appearance.

[0030]

[Table 2]

[0031]

[Table 3]

On the other hand, in Comparative Examples 1 and 2, the compounding ratio is out of the range of the present invention, and in Comparative Example 3, the hydrogenated diene polymer is out of the range of the present invention. Poor balance between flexibility and scratch resistance. Comparative Example 4
This is an example using an olefin-based thermoplastic elastomer (TPO). The pelletization of the olefin-based thermoplastic elastomer is performed by a BR Banbury-type lab plastic mill preheated to 160 ° C. [manufactured by Toyo Seiki Seisaku-sho, 250 c
c) EPDM (ethylene-α-olefin copolymer rubber) shown in Table 4 [EP98, manufactured by Nippon Synthetic Rubber Co., Ltd.]
A] and the polyolefin resin P-1 were added and kneaded for 1 minute. Next, process oil is added, and after the polyolefin resin is melted and the added components are uniformly mixed, a crosslinking agent and a crosslinking aid are added, and kneading is continued for about 10 minutes while heating to 190 ° C. Was. When the added cross-linking agent worked almost 100%, it was taken out and formed into a sheet, and an olefin-based thermoplastic elastomer pellet was obtained with a sheet cutter. The rotation speed of the rotor during kneading was 60 rpm. Powdering and molding were performed in the same manner as in the examples. Table 4 shows the results of the physical property evaluation. Comparative Example 4 using an olefin-based thermoplastic elastomer is inferior in molded appearance, scratch resistance, and fogging properties.

[0033]

[Table 4]

[0034]

According to the present invention, by blending a polyolefin-based polymer and a hydrogenated diene-based polymer having a specific structure, the composition is rich in flexibility, excellent in mechanical properties, excellent in scratch resistance, and has a plasticizer and the like. A powder resin composition having good moldability such as powder fluidity can be obtained without causing stickiness, fogging and the like. The composition of the present invention is used as various molded products by powder molding, and by taking advantage of its excellent properties, handles, skin materials such as levers, instrument panels, console boxes, skin materials such as door trims, pillar garnishes and the like. It can be used widely for automotive interior applications, bags, shaver cases, video cases and other cases, stationery, toys and the like.

Claims (1)

[Claims] 1. A polyolefin polymer 20 to 8
0% by weight, (b) a hydrogenated diene-based polymer in which at least 80% of the double bonds of the conjugated diene portion of the conjugated diene-based polymer have a vinyl bond content of 60% by weight or more.
A powdered resin composition containing 0% by weight (however, (a) + (b) = 100% by weight).