JP2003192838A - Powder molding resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a powder molding resin composition which can easily be produced and can be subjected to a powder molding processing to give the molded article that has excellent creasing resistance when demolded, and further has improved heat resistance, improved abrasion resistance and excellent adhesiveness to polyurethane foams. <P>SOLUTION: This powder molding resin composition comprises (1) 20 to 80 pts.wt. of a polypropylene resin composition comprising (a) 20 to 80 wt.% of polypropylene resin and (b) 80 to 20 wt.% of an olefinic thermoplastic elastomer, (2) an aromatic vinyl compound-conjugated diene copolymer hydrogenation product in an amount of 80 to 20 pts.wt. [the total amount of (1) and (2) is 100 pts.wt.], and (3) a polyester resin comprising (A) a polybasic carboxylic acid component such as cyclohexanedicarboxylic acid and (B) an alcohol component such as 2-ethyl-2-butyl-1,3-propanediol. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for powder molding, and more specifically, it enables the production of a molded article having excellent crease resistance and adhesion to a polyurethane foam, and its preparation is easy. The present invention relates to a resin composition for powder molding.

[0002]

2. Description of the Related Art As a skin material for interior parts such as an instrument panel, a console box, a door trim and a glove box of an automobile, a soft vinyl chloride resin molded product has been used. However, recently, a molded product made of a resin which does not generate hydrogen chloride at the time of incineration of waste products and which is made of an olefin resin material which can be easily recycled is desired. Therefore, many olefin resin compositions have been proposed as powder molding materials (for example, JP-A-5-1183, JP-A-5-5050, JP-A-6-170871, and JP-A-6-). 22
6763, Japanese Patent Laid-Open No. 7-178742, Japanese Patent Laid-Open No. 8-217927, etc.). However, according to these, molded products generally have poor light resistance, and are not as flexible as conventional soft vinyl chloride resins, and when a softening agent is added, there is a problem that bleeding occurs on the surface of the molded product and it becomes sticky. .

As a result of studying to solve the above problems, the present applicant has found that S of styrene and butadiene having a bound styrene content of 20 to 50% by weight and a number average molecular weight in a specific range.
BS type block copolymer (S: polystyrene block,
B: polybutadiene block) hydride (SEBS)
It has been found that a composition containing a is suitable as a powder molding material such as a skin of an interior material of an automobile (Japanese Patent Laid-Open No. 5-279).
No. 484). Furthermore, in order to improve the heat resistance of the molded product using the above hydride, polypropylene resin (P
P) (Japanese Patent Application Laid-Open No. 7-82433),
Further, a method of blending a polyolefin (Japanese Patent Laid-Open No. 2000-
336219) and the like have been proposed.

However, since PP has a low compatibility with SEBS, it has poor processability, and it is difficult to obtain a composition in which both are evenly mixed, and slush molding due to the high crystallinity of PP. However, there is a problem that the molded product is likely to be wrinkled when the mold is removed. Further, when the molded product is used as an interior material for an automobile instrument panel or the like, it is used by laminating it with a polyurethane foam, but PP and SEBS do not have polar groups and have sufficient adhesive strength. There were things I couldn't get.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to facilitate production and to provide excellent crease resistance during demolding in powder molding. It is an object of the present invention to provide a resin composition for powder molding, which enables production of a molded article having improved adhesiveness with a polyurethane foam.
The present inventors, as a result of studies to achieve the above object, a polypropylene resin composition comprising a polypropylene resin and an olefinic thermoplastic elastomer has improved compatibility with SEBS, and wrinkles do not occur during demolding. By adding a polyester resin having a specific molecular structure to these,
It was found that the adhesiveness with a polyurethane foam is also improved, and the present invention has been completed based on this finding.

[0006]

Thus, according to the present invention, (1) (a) polypropylene resin 20 to 80% by weight
And (b) olefinic thermoplastic elastomer 80-2
Polypropylene resin composition 20 to 8 consisting of 0% by weight
0 parts by weight and (2) 80 to 20 parts by weight of a hydride of an aromatic vinyl compound-conjugated diene copolymer ((1) and (2)
Is 100 parts by weight. ), (3) a polyvalent carboxylic acid component (A) containing at least cyclohexanedicarboxylic acid or a derivative thereof, and (i) a hydrogen atom is not bonded between two carbon atoms to which a hydroxyl group is bonded. The number average molecular weight is 7,500 to 100,000, which is obtained by polycondensing an alkanediol having a molecular structure in which carbon atoms are sandwiched and (ii) an alcohol component (B) containing a polyhydric phenoxy alcohol. Provided is a resin composition for powder molding, which comprises a polyester resin in an amount of 2 to 30 parts by weight based on 100 parts by weight of the total of (1) and (2).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The polypropylene resin composition (1) used in the present invention is
(A) Polypropylene resin 20 to 80% by weight, preferably 30 to 70% by weight, and (b) olefinic thermoplastic elastomer 80 to 20% by weight, preferably 70 to 30% by weight (provided that (a) and (b The total of) is 100% by weight.). If the polypropylene resin is too small, the heat resistance will decrease, and if it is too large, creases are likely to occur during demolding, which is not preferable.

The proportion of the polypropylene resin composition (1) and the hydride (2) of the aromatic vinyl compound-conjugated diene copolymer is such that (1) is 20 to 80 parts by weight, preferably 30 to 70 parts by weight. , (2) is 80 to 20 parts by weight, preferably 70 to 30 parts by weight (however, the sum of (1) and (2) is 100 parts by weight). If the polypropylene resin composition (1) is too small, the meltability will decrease, and if it is too large, creases will easily occur and the scratch resistance of the molded product will decrease, such being undesirable.

The polypropylene resin used in the present invention is
Propylene homopolymer (crystalline) or propylene 50
It is a copolymer of at least wt% and another α-olefin having 2 to 12 carbon atoms. Here, propylene and C2-12
The copolymers with α-olefins include random copolymers, alternating copolymers, and linear and radial block copolymers. These polypropylene resins are usually produced by polymerizing using a Ziegler-Natta catalyst or the like. Examples of the α-olefin include ethylene, butene-1, 4-methyl-pentene-1, octene-1 and the like. The melt flow rate (hereinafter referred to as MFR) of the polypropylene resin is not particularly limited, but one having an MFR according to JLS K7210 (load 2.16 kg, measurement temperature 230 ° C., unit: g / 10 min.) Is 5 or more. It is preferable that the MFR is 20 or more. If the MFR of the polypropylene resin is too small, the meltability is poor and pinholes may easily occur in the molded product, which is not preferable.

The olefinic thermoplastic elastomer used in the present invention is usually called TPO or TPE, in which polyolefin such as polyethylene or polypropylene is used for the hard segment and polyolefin rubber such as ethylene-propylene rubber is used for the soft segment. Is. For example, a blend of EPR (ethylene-propylene copolymer rubber) or EPDM (ethylene-propylene-non-conjugated diene monomer terpolymer rubber) with PP or PP / PE (polyethylene), or the above blend with P
EP in the matrix phase of PP etc. by so-called dynamic crosslinking which cross-links EPDM etc. under the melting of P or PP / PE
Dispersed DM (elastomer alloy), referred to as Reactor TPO, which has many ethylene / propylene copolymer (EPR) block parts obtained by copolymerizing propylene and ethylene after polymerization of PP. Examples thereof include propylene block copolymers. These are all commercially available products and are available. Of these, a propylene block copolymer (Reactor TPO) is preferable, and P.I. E. R.
Is marketed as.

The ratio of the polypropylene block component (PP component) of the ethylene / propylene copolymer block component (EPR component) of the propylene block copolymer (reactor TPO) is 1 to 40% by weight, preferably PP component. 5 to 20% by weight, and EPR component is 60 to 9
It is 9% by weight, preferably 80 to 95% by weight. Also,
The EPR component is composed of a random copolymer of ethylene and propylene, and the proportion of monomer units based on ethylene is usually 10 to 40 mol%, preferably 15 to 35 mol%. Further, the propylene-based block copolymer has a molecular weight of 6 to 30 dl / g as an intrinsic viscosity measured in a tetralin solvent at 135 ° C., preferably 10 to 20 d.
1 / g. When the intrinsic viscosity of the propylene-based block copolymer is less than 6 dl / g, the recoverability after elastic deformation is impaired, and when it exceeds 30 dl / g, the fluidity at the time of melting decreases,
Powder molding becomes extremely difficult.

Aromatic vinyl compound used in the present invention
As the hydride of the conjugated diene copolymer, styrene, α
-Random copolymer obtained by random or block copolymerization of at least one aromatic vinyl compound such as methylstyrene and vinyltoluene and at least one conjugated diene such as butadiene, isoprene and 1,3-pentadiene Alternatively, it is obtained by hydrogenating the conjugated diene unit of the block copolymer. Of these, hydrogenated block copolymers are preferable.

The above random copolymer is styrene-butadiene copolymer rubber (SBR), and the block copolymer is ABA type linear and radial block copolymer (A is polystyrene block, B is polybutadiene block or polyisoprene). Blocks) are preferred. The hydrogenated block copolymers described above are SEBS, SEPS (S: polystyrene, E:
Polyethylene, B: polybutylene, P: polypropylene) are commonly called. These hydrides are usually
80 mol% or more, preferably 90 mol% or more, more preferably 95 mol% or more of the unsaturated double bonds in the polymer chain are hydrogenated. Content of aromatic vinyl compound unit in aromatic vinyl compound-conjugated diene copolymer (hereinafter, it may be referred to as bonded aromatic vinyl amount).
Is usually 5 to 50% by weight, preferably 10 to 30% by weight. If the amount of the bound aromatic vinyl is too small, blocking tends to occur during powder molding, which is not preferable. If it is too large, the hardness of the molded product increases, which is not preferable.

The powder molding resin composition of the present invention further comprises a polyvalent carboxylic acid component (A) containing cyclohexanedicarboxylic acid or a derivative thereof, and (i) two carbons each having a hydroxyl group bonded thereto. Polycondensation of an alkanediol having a molecular structure in which carbon atoms to which hydrogen atoms are not bonded are sandwiched between atoms, and (ii) an alcohol component (B) containing a polyhydric phenoxy alcohol,
A polyester resin (3) having a number average molecular weight of 7,500 to 100,000 (hereinafter simply referred to as a polyester resin) is added.

Polyester resin used in the present invention (3)
Is a polyvalent carboxylic acid component (A) having cyclohexanedicarboxylic acid or a derivative thereof, and (i) a carbon atom to which a hydrogen atom is not bonded is sandwiched between two carbon atoms bonded to a hydroxyl group. And (ii) a polyhydric alcohol component (B) containing a polyhydric phenoxy alcohol.
Its glass transition temperature is usually 20 ° C. or higher, preferably 3
The temperature is 0 to 100 ° C, more preferably 40 to 80 ° C, and most preferably 50 to 70 ° C. The hydroxyl value is usually
0.1-20 mg KOH / g, preferably 1-10 mg
KOH / g, more preferably 2 to 5 mgKOH / g.

The number average molecular weight of this polyester resin (number average molecular weight in terms of standard polystyrene measured by gel permeation chromatography (GPC)) is 7,
It is in the range of 500 to 100,000, preferably 1.
10,000-50,000, more preferably 12,50
It is in the range of 0 to 30,000. When the molecular weight is excessively small, the strength characteristics of the molded product using the resin composition of the present invention deteriorates, which is not preferable. On the other hand, if it is excessively large, the miscibility and dispersibility in the resin composition deteriorate, which is not preferable.

The polyvalent carboxylic acid component (A) used in the synthesis of the polyester resin used in the present invention contains at least cyclohexanedicarboxylic acid or its derivative. Examples of the cyclohexanedicarboxylic acid include cyclohexane-1,4-dicarboxylic acid and cyclohexane-1 having a cyclohexane ring as a basic skeleton and having a carboxyl group bonded to carbon at the 1-position, 4-position or 3-position, respectively. , 3-dicarboxylic acid. Of these, cyclohexane-1,4-dicarboxylic acid is preferable.

Examples of these cyclohexanedicarboxylic acid derivatives include ester compounds and acid halides. Of these, ester compounds are preferable, and those having an ester group having an alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, amyl, and hexyl are preferable.

Specific examples of cyclohexane-1,4-dicarboxylic acid and 1,3-dicarboxylic acid include, for example, cyclohexane-1,4-dicarboxylic acid, 2-methyl-cyclohexane-1,4-dicarboxylic acid and 2-ethyl. -Cyclohexane-1,4-dicarboxylic acid, 2-propyl-cyclohexane-1,4-dicarboxylic acid, 2-t-butyl-cyclohexane-1,4-dicarboxylic acid, 2-t-butyl-cyclohexane-1,4- Dicarboxylic acid, 2,3-dimethyl-cyclohexane-1,4-dicarboxylic acid, 2,
3-diethyl-cyclohexane-1,4-dicarboxylic acid, 2,3-dipropyl-cyclohexane-1,4-dicarboxylic acid, 2,3-dibutyl-cyclohexane-1,
4-dicarboxylic acid, 2-methyl-3-ethyl-cyclohexane-1,4-dicarboxylic acid, 2-methyl-3-propyl-cyclohexane-1,4-dicarboxylic acid, 2-methyl-3-butyl-cyclohexane-1 , 4-dicarboxylic acid, 2-ethyl-3-propyl-cyclohexane-
1,4-dicarboxylic acid, 2-ethyl-3-butyl-cyclohexane-1,4-dicarboxylic acid, 2-methyl-3-
Cyclohexane-1,4-dicarboxylic acids such as t-butyl-cyclohexane-1,4-dicarboxylic acid and the like, and their corresponding 1,3-dicarboxylic acids.

The proportion of cyclohexanedicarboxylic acid in the polycarboxylic acid component (A) is usually 50% by weight or more, preferably 80% by weight or more, more preferably 90% by weight or more. Further, the polyvalent carboxylic acid component may contain a polyvalent carboxylic acid other than the above. Examples of other polycarboxylic acids include aromatic polycarboxylic acids, linear or branched aliphatic polycarboxylic acids, and derivatives thereof. Examples of derivatives of these polyvalent carboxylic acids include ester compounds and acid halides. Among them, ester compounds are preferable,
Those having an ester group having an alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, amyl and hexyl are preferable.

The polyvalent carboxylic acid component may contain a monovalent carboxylic acid or a derivative thereof within the range in which the effect of the polyester resin is not impaired, and the permissible amount thereof is within the polyvalent carboxylic acid component. Of less than 10% by weight,
It is preferably 5% by weight or less, more preferably 2% by weight or less. Examples of the monovalent derivatives of carboxylic acids may be the same as those mentioned as examples of other polycarboxylic acid derivatives of the above follow.

The polyhydric alcohol component (B) used in the synthesis of the polyester resin is (i) a molecule in which a carbon atom not bound to a hydrogen atom is sandwiched between two carbon atoms bound to a hydroxyl group respectively. It contains an alkanediol having a structure (hereinafter sometimes referred to as “hindered glycol”) and (ii) a polyhydric phenoxy alcohol.

Specific examples of the hindered glycol include:
For example, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol,
2,2-dipropyl-1,3-propanediol, 2,
2-dibutyl-1,3-propanediol, 2-methyl-2-hexyl-1,3-propanediol, 2-methyl-2-pentyl-1,3-propanediol, 2-ethyl-2-butyl-1 , 3-propanediol, 2-ethyl-2-pentyl-1,3-propanediol and the like. Among these, 2,2-diethyl-1,3
-Propanediol, 2,2-dipropyl-1,3-propanediol, 2,2-dibutyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 2-methyl-2 -Pentyl-1,3-propanediol and the like are preferable.

Examples of the (ii) polyhydric phenoxy alcohol in the polyhydric alcohol component are those obtained by the addition reaction of polyhydric phenol and alkylene oxide, and the phenolic hydroxyl group in the polyhydric phenol is linked with an ether bond. It has been modified to an alcoholic hydroxyl group via Examples of the polyhydric phenol include catechol, resorcin, hydroquinone, 4-methylpyrocatechol,
Dihydric phenols such as 4-methylresorcinol, 5-methylresorcinol and 2-methylhydroquinone;
Trivalent phenols such as 2,3-benzenetriol, 1,2,4-benzenetriol and 1,3,5-benzenetriol; 4,4'-dihydroxydiphenylmethane,
Non-condensed polycycles such as 2,2-bis (4'-hydroxyphenyl) propane (bisphenol A), 3,4-bis (4'-hydroxyphenyl) hexane and 4,4 ', 4 "-triphenylmethanetriol Formula phenols are preferred, and of these, 2,2-bis (4'-hydroxyphenyl) propane (bisphenol A) is preferable, and biphenyl-4,4'-diol and biphenyl-2,2'-diol are preferred. A hydroxybiphenyl compound such as biphenyl-2,3'-diol can also be used, and examples of the alkylene oxide include ethylene oxide and propylene oxide.

Specific examples of the polyhydric phenoxy alcohol include, for example, ethylene oxide adduct of 4,4'-dihydroxydiphenylmethane, ethylene oxide adduct of bisphenol A, and ethylene oxide adduct of biphenyl-4,4'-diol. Is mentioned. Among these, ethylene oxide adduct of bisphenol A is preferable.

The proportion of (i) hindered glycol and (ii) polyhydric phenoxy alcohol in the polyhydric alcohol component is usually 80 to 100% by weight, preferably 90 to 1%.
It is 00% by weight, more preferably 95 to 100% by weight. Moreover, the ratio of (i) hindered glycol and (ii) polyhydric phenoxy alcohol is 5 / 95-5 by molar ratio.
It is 0/50, preferably 7/93 to 40/60, and more preferably 10/90 to 30/70.

The polyhydric alcohol component may contain other polyhydric alcohols, and examples thereof include alkane diols other than the hindered glycols, cyclohexane diols, aromatic diols and the like. The polyhydric alcohol component contains a monohydric alcohol within a range that does not impair the effects of the present invention, and the permissible amount thereof is
It is usually 10% by weight or less, preferably 5% by weight or less, and more preferably 3% by weight or less in the polyhydric alcohol component.

The polyester resin of the present invention can be synthesized, for example, by polycondensing the polyhydric carboxylic acid component (A) and the polyhydric alcohol component (B). The polycondensation reaction may be carried out according to a conventional method, for example, a reaction temperature of 10
The temperature is 0 to 300 ° C, preferably 150 to 280 ° C, more preferably 180 to 230 ° C. Examples of the solvent include water-insoluble organic solvents that are azeotropic with water, such as toluene and xylene. The reaction pressure is 0.1 to 200 mmHg
(1.3 × 10 ^{2 to} 2.7 × 10 ⁵ Pa), preferably 0.5 to 100 mmHg (6.6 × 10 ^{2 to} 1.3 × 1)
0 ⁵ Pa), more preferably 1 to 30 mmHg (1.3
× 10 ^{3 to} 4.0 × 10 ⁴ Pa). It is also possible to carry out the reaction in the presence of an inert gas. For the polycondensation reaction, conventionally used esterification catalysts, for example, Bronsted acids such as p-toluenesulfonic acid, sulfuric acid, phosphoric acid; calcium acetate, zinc acetate, manganese acetate, zinc stearate, alkyltin oxide. Organic metal compounds such as dialkyl tin oxide and titanium alkoxide; metal oxides such as tin oxide, antimony oxide, titanium oxide and vanadium oxide. Among them, an organometallic compound of Group IV of the periodic table is preferable, and the obtained polyester resin has good oxidation stability.

The above polyester resin is contained in an amount of 2 to 30 parts by weight per 100 parts by weight of the polypropylene resin composition (1) and the hydride (2) of the aromatic vinyl compound-conjugated diene copolymer. , Preferably 5 to 20 parts by weight. If the addition amount of the polyester resin is too small, the adhesiveness between the molded body and the polyurethane foam is not improved, and if it is too large, the adhesiveness reaches a saturated state,
Not only is it uneconomical, but the strength of the molded product may be reduced.

When the polyester resin is used, dibutyltin is used as a catalyst for promoting the reaction with the isocyanate compound in the foam forming raw material liquid in order to enhance the adhesiveness (adhesion) between the molded product and the polyurethane foam. Organotin compounds such as dilaurate and dibutyltin distearate,
It is preferable to use a tertiary amine compound such as tetraalkylethylenediamine, N, N′-dialkylbenzylamine, a fatty acid salt such as cobalt naphthenate and zinc stearate, and a carboxylate of an alkali metal.
The amount of these catalysts is about 0.01 to 5 parts by weight per 100 parts by weight of the resin composition of the present invention.

If desired, various additives can be added to the resin composition of the present invention. In particular, it is preferable to add a modified silicone oil in order to improve the wear resistance and releasability of the molded product without lowering the adhesiveness between the molded product and the polyurethane foam. The modified silicone oil is obtained by introducing a functional group into polysiloxane, and is roughly classified into four types, that is, a functional group introduced into a side chain, both ends, both side chains and both ends, and one end. As the functional group, one or two of a carboxyl group, a hydroxyl group, a mercapto group, an amino group, an epoxy group, and an unsaturated bond ((meth) acryloyloxy group, vinyl group, etc.) is introduced. The molecular weight of oligomers is about tens of thousands, and various modified silicone oils are commercially available. Although modified silicone oils having various structures can be obtained depending on the starting materials and the synthesis method, the chemical structural formula is not particularly limited in the present invention. The chemical structural formulas of typical modified silicone oils are shown in the general formulas (1) to (4), but are not limited thereto. A preferred functional group is a functional group having active hydrogen which is reactive with isocyanate as a raw material of the polyurethane foam. Also, both ends introduced type is preferable. The molecular weight of the modified silicone oil is not particularly limited, but the preferable molecular weight is about 1,000 to 30,000.

[0032]

The modified silicone oil is preferably added in an amount of 10 parts by weight or less, more preferably 0.5 to 100 parts by weight, based on 100 parts by weight of the above-mentioned polymer components (1) and (2).
5 parts by weight. If the amount of the modified silicone oil added is too small, the abrasion resistance of the molded product is not improved, and if it is too large, bleeding may occur on the surface of the molded product.

Additives other than the modified silicone oil include, for example, barium stearate, calcium stearate, magnesium stearate, zinc stearate, aluminum stearate in order to improve mold release during molding and prevent blocking during storage. Metal soaps such as rate and fatty acid esters of polyhydric alcohol can be added. As other additives, various known stabilizers,
Antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, pigments and the like can be added. Further, a known plasticizer may be added within a range that does not cause stickiness or impair the moldability.

Further, a polymer other than the above-mentioned polymer components may be used in combination within the range not impairing the gist of the present invention. Examples of such a polymer include acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-styrene resin (AS resin), ethylene-vinyl acetate resin (EVA resin), norbornene resin, polyamide resin, polyester resin. Resin, polycarbonate resin, polybutadiene resin and the like can be mentioned.
Furthermore, an aromatic vinyl compound-α-olefin copolymer obtained by copolymerizing an aromatic vinyl compound such as styrene with an α-olefin such as ethylene or propylene (for example, JP-A-3-7705, JP-A-7-
70223, JP-A-10-168112, and the like). The amount of these other polymers used is in the range of 40% by weight or less, preferably 30% by weight or less in the resin composition of the present invention.

The method for producing the resin composition for powder molding of the present invention is not particularly limited. Further, the form or shape of each polymer component used is not particularly limited. As a manufacturing method, for example, the component (1) and the component (2) are put into a mixer all at once, mixed, and then mixed with the polyester resin component (3). First, (i) polypropylene resin composition Was prepared using a conventional mixer such as a roll, a single-screw or twin-screw extruder, a Banbury mixer, and a kneader, and (ii) the same as the above with the hydride of the aromatic vinyl compound-conjugated diene copolymer. And (iii) further mixing with a polyester resin for production.

The resin composition for powder molding of the present invention is used in powder form. To make the resin composition into a powder, a powdery resin composition having excellent powder fluidity is obtained by pulverizing with a conventionally known pulverizer such as a turbo mill, a roller mill, a ball mill, a centrifugal force pulverizer, and a pulverizer. Can be adjusted. The particle size of the powder is usually 50 to 500 μ.
m, preferably 100 to 300 μm. If this average particle size is too small, the efficiency of the crushing process is poor and it tends to agglomerate during storage. Conversely, if it is too large, the texture of the molded product will become rough, and pinholes will occur in the case of thin molded products. It is not preferable because it is easy to

Such a powdery resin composition for powder molding of the present invention can be applied to various powder molding methods such as powder slush molding, fluidized-bed molding or powder rotational molding, and particularly, instrument panels. It can be suitably used as a powder molding material for the surface layer of automobile interior parts such as headrests, console boxes, door trims and armrests.

[0039]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples. The number of parts and% are based on weight unless otherwise specified. The test method is as follows.

(1) Slush molding using a crease-resistant powder-forming resin composition powder,
The sheet-shaped molded product (thickness is about 1 mm) is released from the mold without folding creases left, and a test piece of 15 × 50 mm is cut out. This test piece is bent 180 degrees in a room at 23 ° C., placed on a horizontal surface in that state, placed with a weight of 1 kg for 10 seconds and removed, and after the shape is sufficiently recovered, the angle between the horizontal surface and the folded sheet is measured. Similarly 65
Carry out at ° C. The smaller the value, the better the crease resistance.

(2) Abrasion resistance A 30 × 80 mm test piece cut out in the same manner as in (1) was placed on a table on which it can reciprocate, and a width of 20
mm steel friction element (4 pieces of gold width 3 stacked and covered) is placed on the test piece, and a load of 2.5 kgf is applied to the test piece, and the surface of the test piece is reciprocated 5 times at a speed of 60 cycles / minute. Then, the degree of whitening of the surface of the test piece at that time was observed. The display of the results is as follows. ○: No whitening △: Slightly whitening ×: Whitening

(3) Heat resistance A 150 × 100 mm test piece cut in the same manner as in (1) is left in an oven at 120 ° C. for 100 hours. After that, the test piece taken out was left at room temperature for 1 hour, and the degree of stickiness on the surface was evaluated with a tentacle. The display of the results is as follows. ○: The surface is not sticky ×: The surface is sticky

(4) Adhesion with polyurethane foam layer A test piece of 145 × 200 mm cut in the same manner as in (1) was 147 (vertical) × 217 (horizontal) × 10 (depth) mm.
Into the mold, the polyurethane foam forming liquid (functional group number 2.
A mixture of 16 g of Polymeric MDI (4,4′-diphenylmethane diisocyanate) of 7 and 31.4 g of polyether polyol (trifunctional, hydroxyl value 50) (including 1.0% of triethylenediamine and 1.6% of water). Pour and seal the mold. After leaving the mold at room temperature for 10 minutes, the test piece on which the polyurethane foam layer was laminated was taken out from the mold, the test piece was peeled from the foam layer, and the area of the cohesively broken foam layer was measured to occupy the entire area of the test piece. Find the percentage.
The larger this ratio, the better the adhesion. ○: 90 to 100% △: 80% to less than 90% ×: less than 80%

Production Example 1 (Polyester Resin A) 100 parts of cyclohexane-1,4-dicarboxylic acid, 2-
Ethyl-2-butyl-1,3-propanediol (hydroxyl value 695 mg KOH / g) 14.3 parts, ethylene oxide adduct of bisphenol A (hydroxyl value 344 mg
A polycondensation reaction was carried out using 164.3 parts of KOH / g) and 0.28 part of monobutyltin oxide as an esterification catalyst. The obtained polyester resin A had a number average molecular weight of 13,660, a hydroxyl value of 7.2 mgKOH / g and a glass transition temperature of 53 ° C.

Production Example 2 (Polyester Resin B) Cyclohexane-1,4-dicarboxylic acid 100 parts, 2-
Ethyl-2-butyl-1,3-propanediol (hydroxyl value 695 mg KOH / g) 76.5 parts, ethylene oxide adduct of bisphenol A (hydroxyl value 344 mg
Polycondensation reaction was carried out using 38.7 parts of KOH / g) and 0.22 parts of monobutyltin oxide as an esterification catalyst. The obtained polyester resin B had a number average molecular weight of 7,930, a hydroxyl value of 9.8 mgKOH / g, and a glass transition temperature of 49 ° C. The number average molecular weight of the polyester resin is a standard polystyrene equivalent molecular weight measured by GPC. The hydroxyl value was determined by acetylating the polyester resin with acetic anhydride and then titrating it with a potassium hydroxide / ethanol mixed solution. The glass transition temperature was measured by DSC.

Examples 1 to 7 and Comparative Examples 1 to 2 Polymer components of the types and amounts shown in Table 1 were kneaded by a twin-screw extruder (TEM35B manufactured by Toshiba Machine Co., Ltd.), pelletized, and then turbo milled. Was pulverized to obtain a powdery resin composition for powder molding. Using each of the obtained powdery resin composition, while performing a meltability test by slush molding, using the obtained sheet crease resistance, wear resistance,
The heat resistance and the adhesiveness with the polyurethane foam were evaluated. The results are shown in Table 1.

[0047] (Note) (1) Sun Allomer PM940M (MFR
30) (2) Same as above Sun Attack (Atactic PP) (3) Tokuyama P.P. E. R. M142E (Reactor TPO) (4) Asahi Kasei Tuftec H1221 (bound styrene amount 12%) (5) GE Toshiba Silicone XF42-B0970
(Carbinol modified silicone oil) (6) Chisso Corp. Silaplane FM-0721 (methacryloxy group modified silicone oil at one end)

From the results of Table 1, PP resin composition and SEBS
It is found that when and are mixed and the polyester resin A or B is mixed therein (Examples 1 to 7), the crease resistance is good and the adhesion to the polyurethane foam is also good. Among them, it is understood that the combined use of the modified silicone oil (Examples 5 and 7) further improves the abrasion resistance without lowering the adhesiveness. On the other hand, when the polyester resin A or B is not blended (Comparative Example 1), the adhesiveness is lowered, and when the olefin elastomer is not blended (Comparative Example 2), the crease resistance is poor. It can be seen that the adhesiveness with the polyurethane foam also decreases.

[0049]

EFFECTS OF THE INVENTION According to the present invention, a resin composition for powder molding is provided, which is easy to manufacture and can obtain a powder molded article excellent in crease resistance, heat resistance, abrasion resistance and the like.

Continued front page    (72) Inventor Satoshi Iwabuchi             1-2-1 Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa             ON Kasei Co., Ltd. Kawasaki Laboratory (72) Inventor Koichi Yanai             1-2-1 Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa             ON Kasei Co., Ltd. Kawasaki Laboratory (72) Inventor Toshiya Kobayashi             1-2-1 Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa             ON Kasei Co., Ltd. Kawasaki Laboratory F-term (reference) 4J002 AC11W BB03X BB12X BB12Y                       BB14Y BB15X BP01W CF034                       CF124 FD150 FD160 FD20X                       FD204 GN00 HA09

Claims (4)

[Claims] (1) (a) Polypropylene resin 20 to
20 to 80 parts by weight of a polypropylene resin composition comprising 80% by weight and (b) 80 to 20% by weight of an olefinic thermoplastic elastomer, and (2) an aromatic vinyl compound-
80 to 20 parts by weight of a hydride of the conjugated diene copolymer (the total of (1) and (2) is 100 parts by weight),
(3) A polycarboxylic acid component (A) containing at least cyclohexanedicarboxylic acid or a derivative thereof, and (i)
An alcohol component (B) containing an alkanediol having a molecular structure in which a carbon atom to which a hydrogen atom is not bound is sandwiched between two carbon atoms to which a hydroxyl group is bound, and (ii) a polyhydric phenoxy alcohol And polycondensed with a number average molecular weight of 7,500 to 100,00
A total of 10 of (1) and (2) polyester resin that is 0
A resin composition for powder molding containing 2 to 30 parts by weight based on 0 parts by weight. 2. An olefinic thermoplastic elastomer,
The resin composition for powder molding according to claim 1, which is a propylene-based block copolymer. 3. The powder according to claim 1, wherein the hydride of the copolymer of an aromatic vinyl compound and a conjugated diene is a hydride of a block copolymer of an aromatic vinyl compound and a conjugated diene. Molding resin composition. 4. The resin composition for powder molding according to claim 1, further comprising a modified silicone oil in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the total of (1) and (2).