JPH06286039A - Laminate composed of thermopolastic elastomer - Google Patents

Abstract

PURPOSE:To obtain a laminate, substantially free from oil bleeding and excellent in appearance, by laminating a partially crosslinked layer of an elastomer compsn. prepared by mixing oil-extended olefinic copolymer rubber and the others with olefinic copolymer rubber specified in viscosity and a polyethylene foam layer. CONSTITUTION:Oil-extended olefinic copolymer rubber prepared by adding 20-150 pts.wt. of a mineral oil type softener to 100 pts.wt. of olefinic copolymer rubber with Mooney viscosity at 100 deg.C (M1L+4100 deg.C) of 120-350 is used as a base. A laminate composed of a thermoplastic elastomer compsn. is obtained by laminating a thermoplastic elastomer compsn. layer formed by partially crosslinking a mixture consisting of 40-95wt.% of the base and 5-60wt.% of a propylene polymer resin and a polyethylene or a polypropylene foam layer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminate. More specifically, it relates to a laminate effectively used as an interior material for automobiles.

[0002]

2. Description of the Related Art As an interior material for automobile floors, walls, ceilings, etc., the surface is embossed and has a polyvinyl chloride layer with a leather pattern on it, which has a foam layer and a necessary layer. Accordingly, a laminated body sequentially lined with a resin aggregate layer has been conventionally used. Such a laminated body is manufactured through the following steps.

(1) A sheet is produced by calendering soft polyvinyl chloride. (2) The surface of this sheet is coated with a mixture of polyol and polyisocyanate and subjected to urethane treatment to carry out matte treatment. This matte treatment is the step (7) described later.
The purpose is to prevent the surface of the sheet from becoming glossy during thermoforming. (3) Embossing is performed to form a textured leather pattern on the surface. (4) The surface of the sheet having the embossed surface is subjected to flame treatment to be melted, and pressure-bonded with a separately supplied foamed polyurethane sheet by a roll. (5) An adhesive layer is further provided on the foamed polyurethane sheet side of the laminated sheet of the polyvinyl chloride sheet and the foamed polyurethane sheet. (6) A resin aggregate having a predetermined shape is formed by a thermoforming method such as vacuum forming or pressure forming. (7) After the polyvinyl chloride-foamed polyurethane-adhesive laminate sheet is preheated, it is placed on a resin aggregate molded product, and both are thermoformed and integrated.

[0004]

However, as compared with a laminate of such polyvinyl chloride sheet and foamed polyurethane sheet, a partially crosslinked product of an oil-extended olefin copolymer rubber and a propylene polymer resin is used. It has been found that a laminate obtained by laminating a thermoplastic elastomer layer made of a blended product with a polyethylene or polypropylene foam layer, preferably a crosslinked foam layer, is remarkably excellent in some points in terms of production and properties. Was issued.

(A) In such a laminate, a blend of an oil-extended olefin copolymer rubber and a partially cross-linked propylene polymer resin is blended with an extruder at about 150 to 250.
Extruded by a die method, the extruded sheet-like thermoplastic elastomer in a molten state, preferably laminated with a crosslinked foam sheet of polyethylene or polypropylene, is passed between a pair of rolls, in which case the thermoplastic elastomer sheet Is produced by bringing it into contact with the embossing roll side at a roll temperature of about 60 to 70 ° C. and the crosslinked foam sheet on the normal roll side which is not heated. As a result, the steps corresponding to the above steps (1) to (4) in the case of using soft polyvinyl chloride are performed in only one step to give a laminate having the surface embossed. That is, since this laminate does not produce luster during integral molding by heating with an aggregate molded product, which is performed later, it is not necessary to particularly provide a matting step such as the step (2). In addition, in relation to this, in the case of polyvinyl chloride, it is necessary to form it in a sheet shape in advance as in the step (1) in order to perform a matting treatment. In this case, the thermoplastic elastomer can be extruded into a sheet and, at the same time (following), fusion-bonded to the crosslinked foam sheet, which means that the polyurethane foam sheet as seen in the step (4) can be obtained. It also eliminates the need for steps such as flame treatment of the polyvinyl chloride sheet for adhesion with. Moreover, the embossing of the thermoplastic elastomer sheet can be performed simultaneously with the lamination with the crosslinked foam sheet, and it is not necessary to separately provide an embossing step such as the step (3).

(B) This laminate according to the present invention can be placed on a preheated polyolefin resin aggregate molded product having a predetermined shape and thermoformed to be integrated. In that case, the adhesive layer as in the step (5) is not required.

(C) With respect to the properties of the laminate, this laminate is excellent in lightness, flexibility and scratch resistance of the surface, and also contains a conventional flexible olefinic thermoplastic elastomer or a plasticizer. There is no sticky feeling on the surface due to bleeding of a softening agent or a plasticizer as in the case of using soft polyvinyl chloride, and both the thermoplastic elastomer and the crosslinked foam have excellent heat resistance. Since it has excellent heat resistance as a whole, it can be effectively used as an interior material for automobiles whose interior temperature becomes high especially in summer.

[0008]

The inventors of the present invention have conducted extensive studies to overcome the drawbacks of the above-mentioned conventional methods, and as a result, an oil-extended olefin copolymer containing a specific mineral oil softener in advance. The inventors have found that a composition obtained by partially cross-linking a mixture of rubber and a propylene polymer resin is excellent in flexibility and mechanical properties, and completed the present invention. That is, the present invention has a Mooney viscosity of 100 ° C. (ML _{1 + 4} 100 ° C.)
Olefin copolymer rubber 10 having a value of 120 to 350
Oil-extended olefin copolymer rubber (A) 40-9 containing 20-150 parts by weight of a mineral oil-based softening agent per 0 part by weight.
A thermoplastic elastomer composition layer formed by partially cross-linking a mixture of 5% by weight and 5 to 60% by weight of a propylene polymer resin (B) and a foam layer of polyethylene or polypropylene. The present invention relates to a laminate comprising the thermoplastic elastomer composition. The present invention will be specifically described below.

In the present invention, the olefin copolymer rubber used in the oil-extended olefin copolymer rubber (A) is, for example, ethylene-propylene copolymer rubber, ethylene-propylene-non-conjugated diene rubber, It is an amorphous random elastic copolymer containing an olefin as a main component, such as ethylene-butene-non-conjugated diene rubber and propylene-butadiene copolymer rubber. Among these, the ethylene-propylene-non-conjugated diene rubber and the mixture of the ethylene-propylene copolymer rubber and the ethylene-propylene-non-conjugated diene rubber are particularly preferable. As the non-conjugated diene, dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylenenorbornene,
There are ethylidene norbornene and the like, but ethylidene norbornene is particularly preferable.

As a more preferred specific example, the propylene content is 10 to 55% by weight, preferably 20 to 40.
% Ethylene, the content of non-conjugated diene such as ethylidene norbornene is 1 to 30% by weight, preferably 3 to 20% by weight of ethylene-propylene-nonconjugated diene copolymer rubber (hereinafter,
It is called "EPDM". ) And its 100 ° C. Mooney viscosity (ML _{1 + 4} 100 ° C.) is 120-350, preferably 140-300. Propylene content is 1
If it is less than 0% by weight, flexibility tends to be lost, and if it is more than 55% by weight, mechanical properties tend to be deteriorated. If the content of the non-conjugated diene typified by ethylidene norbornene is less than 1%, the mechanical properties will decrease, and if it exceeds 30% by weight, the injection moldability will tend to decrease. If the Mooney viscosity at 100 ° C. (ML _{1 + 4} 100 ° C.) is lower than 120, mechanical properties are lost, and if it is higher than 350, the appearance of the molded product is deteriorated. However, EPDM with Mooney viscosity of 120-350
When using, the mechanical properties are large, the tensile breaking strength and breaking elongation are dramatically improved, and the crosslinking efficiency is increased,
Provides improved mechanical properties, especially strength, compression set. EPDM manufactured by a known method can be used.

The mineral oil-based softening agent used in the present invention is a petroleum fraction having a high boiling point, which is blended for the purpose of improving processability and mechanical properties, such as paraffin-based, naphthene-based or aromatic. Although there are group-based ones, paraffin-based ones are preferably used. When the amount of aromatic components is large, the staining property becomes strong, and there is a limit in the use intended for transparent products or light-colored products, which is not preferable.

The oil-extended olefin copolymer rubber (A) is
Mineral oil-based per 100 parts by weight of olefin-based copolymer rubber
20 to 150 parts by weight of a softening agent, preferably 30 to 120
It is to contain by weight. If less than 20 parts by weight
The flowability of the reffin-based TPE composition is lowered, and especially, the extrusion process
Workability and injection moldability are impaired. On the other hand, 150 parts by weight
If the amount is too high, the plasticity increases remarkably and the processability deteriorates.
In addition, performance such as physical properties of the product will be deteriorated.
Not good. And oil-extended olefin-based copolymer rubber
(A) 100 ° C Mooney viscosity (ML _{1 + 4}100 ° C)
Is preferably 30 to 100, more preferably 40 to 9
It is 0. Below 30 the mechanical properties are lost and 100
If it is higher, the molding process tends to be difficult.

EPDM having a Mooney viscosity of 120 to 350
When a large amount of a mineral oil-based softening agent is blended with, an olefin-based TPE composition capable of satisfying both flexibility and processability improvement by improving fluidity and mechanical properties at the same time is obtained. You can Generally, a mineral oil-based softening agent is used as a fluidity improver in an olefin-based TPE composition.
When PDM is not used, regardless of the viscosity of EPDM, 40 parts of mineral oil type softener is added per 100 parts by weight of EPDM.
If it is blended in an amount of more than 1 part by weight, bleeding of the softening agent will occur on the surface of the TPE composition, and contamination of the product, sticking and the like will be observed, which is not preferable. However, the 100 ° C Mooney viscosity is 120-350.
Of oil-extended EPDM containing 20 to 150 parts by weight of a mineral oil-based softening agent per 100 parts by weight of EPDM of
It is possible to obtain a TPE composition having no bleeding of a softening agent, no product contamination or tackiness being observed, and excellent physical properties such as breaking strength, breaking elongation, and compression set. Despite the large blending ratio of this mineral oil-based softening agent, no bleeding of the softening agent is observed because EPD has a high Mooney viscosity.
It is considered that when M is used, the upper limit of the allowable oil expansion amount of the mineral oil-based softening agent is increased, and the softening agent that is preferably added in advance is uniformly dispersed in EPDM.

A known method is used for the oil extension method of EPDM. For example, using a device such as a roll or a Banbury mixer, a method of oil-extending by a method of mechanically kneading EPDM and a mineral oil-based softening agent, or adding a predetermined amount of a mineral oil-based softening agent to an EPDM solution, and then , A method of removing the solvent by a method such as steam stripping, and the like.
Of these, the preferred oil extension method is a method using an EPDM solution, and the EPDM solution is an EPDM solution obtained by polymerization.
The operation is easier when using a solution.

The propylene polymer resin (B) used in the present invention is preferably polypropylene or a copolymer resin of propylene and an α-olefin having 2 or more carbon atoms. Specific examples of the α-olefin having 2 or more carbon atoms include ethylene, 1-butene, 1-pentene, and 3-methyl-.
1-butene, 1-hexene, 1-decene, 3-methyl-
1-Pentene, 4-methyl-1-pentene, 1-octene and the like. The melt flow rate of these polymer resins is
0.1 to 100 g / 10 minutes is preferable, more preferably
It is in the range of 0.5 to 50 g / 10 minutes. If the melt flow rate is smaller than 0.1 g / 10 minutes or larger than 100 g / 10 minutes, there is a problem in workability. Further, when the amount of the propylene-based polymer resin (B) in the olefin-based TPE composition according to the present invention is less than 5% by weight, the fluidity is deteriorated and the appearance of the molded article is deteriorated. There is no sex.

In order to partially crosslink the mixture of the oil-extended olefin-based copolymer rubber (A) and the propylene-based polymer resin (B), it is preferable to use an organic peroxide. As the organic peroxide, 2,5-dimethyl-2,5-di (t
-Butylperoxy) hexane, 2,5-dimethyl-
2,5-di (t-butylperoxy) hexyne-3,
1,3-bis (t-butylperoxyisopropyl) benzene, 1,1-di (t-butylperoxy) 3,5
5-trimethylcyclohexane, 2,5-dimethyl-
2,5-di (peroxybenzoyl) hexyne-3, dicumyl peroxide and the like. Among these, odorous,
From the viewpoint of scorch property, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane is particularly preferable.

The amount of the organic peroxide added is 0.005 to 2.0 parts by weight, preferably 0.01 to 0.6, based on 100 parts by weight of the total of the oil-extended olefin copolymer rubber (A) and the propylene polymer resin (B). It can be selected within the range of parts by weight. 0.0
If it is less than 05 parts by weight, the effect of the crosslinking reaction is small, and if it exceeds 2.0 parts by weight, it is difficult to control the reaction and it is not economically advantageous.

In producing the composition of the present invention, N, N'-m- serves as a cross-linking aid during partial cross-linking with an organic peroxide.
Multifunctionality such as phenylene bismaleimide, toluylene bismaleimide, P-quinone dioxime, nitrobenzene, diphenylguanidine, trimethylolpropane, divinylbenzene, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate Compounds can be added. By blending such a compound, a uniform and mild crosslinking reaction occurs, and it is possible to improve mechanical properties.

The amount of the crosslinking aid added is selected in the range of 0.01 to 4.0 parts by weight with respect to 100 parts by weight of the total of the oil-extended olefin copolymer rubber (A) and the propylene polymer resin (B). Can be done. It is preferably 0.05 to 2.0 parts by weight.
If it is less than 0.01 parts by weight, the effect is difficult to appear, and if it exceeds 4 parts by weight, it is not economically advantageous.

A specific method for producing a thermoplastic elastomer composition by partially crosslinking a mixture of an oil-extended olefin copolymer rubber (A) and a propylene polymer resin (B) will be described below. The oil-extended olefin-based copolymer rubber (A), the propylene-based polymer resin (B), the organic peroxide, and, if necessary, further a crosslinking auxiliary agent are mixed in a specific ratio and dynamically heat-treated. That is, they are melted and kneaded. As the mixing and kneading device, a conventionally known non-open type Banbury mixer, a twin-screw extruder or the like is used. Kneading temperature is 150 ℃
It may be performed at about 300 ° C. for about 1 to 30 minutes. In the production of this composition, if necessary, auxiliary materials such as an inorganic filler, an antioxidant, a weather resistance agent, an antistatic agent and a coloring agent can be added.

More specifically, the oil-extended olefin-based copolymer rubber (A) and the propylene-based polymer resin (B), and if necessary, a crosslinking aid and the above-mentioned auxiliary materials are blended in a predetermined ratio, and the non-release type kneading is carried out. Using the Banbury mixer of the machine
After sufficiently kneading and homogenizing in a temperature range of 50 to 250 ° C., the obtained composition and an organic peroxide are sufficiently blended with a closed mixer such as a tumbler or a super mixer. Then, the blended product is dynamically heat-treated at 200 to 300 ° C. using a twin-screw continuous extruder or the like capable of obtaining a strong kneading force to obtain a partially crosslinked thermoplastic elastomer composition. .

Examples of the auxiliary material include the following as a specific example of the antistatic agent. That is,
(A) Cationic compounds such as primary amine salts, tertiary amines, quaternary ammonium compounds, and pyridine derivatives,
(B) Sulfated oil, soap, sulfated ester oil, sulfated amide oil, olefin sulfate ester salt, fatty alcohol sulfate ester salt, alkyl sulfate ester salt, fatty acid ethyl sulfonate, alkyl naphthalene sulfonate,
Anionic compounds such as alkylbenzene sulfonate, succinate sulfonate, and phosphate ester salt,
(C) Partial fatty acid ester of polyhydric alcohol, ethylene oxide addition product of fatty alcohol, ethylene oxide addition product of fatty acid, ethylene oxide addition product of fatty acid amino or fatty acid amide, ethylene oxide addition product of alkylphenol, ethylene oxide addition product of alkylnaphthol Adducts, ethylene oxide adducts of partial fatty acid esters of polyhydric alcohols, nonionic ones such as polyethylene glycol, (d) carboxylic acid derivatives, amphoteric ones such as imidazoline derivatives are generally usable, Particularly, nonionic compounds, especially polyoxyethylene alkylamine, polyoxyethylene alkylamide or fatty acid ester thereof, fatty acid ester of glycerin, etc. are preferable.

The above-mentioned antistatic agent may be a single type or a mixture of two or more types. Further, the blending amount is the thermoplastic elastomer composition 1 according to the present invention.
It is preferably about 0.03 to 2 parts by weight, more preferably about 0.04 to 1 part by weight, relative to 00 parts by weight. If the blending ratio is higher than this, exudation to the surface and deterioration of the physical properties of the thermoplastic elastomer composition occur, which is not preferable. By adding this antistatic agent, it is possible to obtain a molded product having flexibility and having no stickiness. Further, the stickiness and the adhesion of dust and the like due to the elimination of the bleeding of the softening agent are reduced, and at the same time, the chargeability which is the original function of the antistatic agent is reduced, and the adhesion of dust due to the electrification is also reduced.

On the other hand, slipperiness may be desired as the property of the surface of the molded article, and higher fatty acid amide can be used for this. Specific examples of the higher fatty acid amide include lauric acid amide, valmitic acid amide,
Saturated fatty acid amides such as stearic acid amide and behenic acid amide, erucic acid amide, oleic acid amide, bridic acid amide, elaidic acid amide and other unsaturated fatty acid amides, methylenebisstearic acid amide, methylenebisoleic acid amide, ethylenebisstearin Acid amides, bis fatty acid amides such as ethylene bisoleic acid amide, and the like are used. Particularly preferred higher fatty acid amides are compounds having a melting point of about 70 ° C to 110 ° C. The amount of the above higher fatty acid amide compounded is preferably about 0.03 to 2 parts by weight, more preferably about 0.04 to 1 part by weight, based on 100 parts by weight of the thermoplastic elastomer composition according to the present invention. If the blending ratio is higher than this, leaching of the higher fatty acid amide to the surface and deterioration of the physical properties of the thermoplastic elastomer composition occur, which is not preferable.

The above-mentioned auxiliary materials can be added at any stage of producing the elastomer composition according to the present invention, at the time of processing or at the time of using the product after processing.

Foams of polyethylene or polypropylene, preferably crosslinked foams, backed by a skin layer formed from a thermoplastic elastomer composition are disclosed, for example, in
39-25500 gazette, 40-25351 gazette and 60-26352 gazette describe a method for producing a cross-linked foam using an azide cross-linking agent. Since these crosslinked foams are commercially available, they can be used as they are. When the laminate is used as an automobile interior material, these foams preferably have a foaming ratio of about 10 to 50 times.

The laminate according to the present invention is obtained, for example, by molding a polyolefin resin aggregate into a predetermined shape, placing the preheated laminate on the formed aggregate molded product, and thermoforming both. It can be used as an integrated molded product.

In the polyolefin resin used for molding the aggregate, wood powder, fiber pieces, inorganic filler, etc. are used within the range not impairing the required physical properties or for the purpose of further improving the physical properties. Can be mixed. These polyolefin-based resin aggregates are generally molded into a predetermined shape in the state of resin board, plastic cardboard, resin felt, or the like.

The thickness of the thermoplastic elastomer layer and the foam layer of the laminate integrally molded with the aggregate molded product is
Depending on the application of the laminate molded product, for example, when used as an interior material for automobiles, the former is generally about 0.1 to
2 mm, the latter is about 1 to 30 mm, and even in such applications, the thickness of the skin layer is relatively thin for ceiling materials and relatively for dashboards, wheel house covers, various pillars, seats, etc. Thick ones are used.

[0030]

EXAMPLES The contents of the present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The test methods used for the sheet forming process and the physical property measurement in these examples and comparative examples are as follows. (1) Mooney viscosity (ML _{1 + 4} 100 ° C): ASTM
According to D-927-57T. Number 1 for EPDM
Was calculated.

[0031]

[Formula 1] log (ML ₁ / ML ₂ ) = 0.0066 (ΔPH
R) ML ₁ : Mooney viscosity of EPDM ML ₂ : Mooney viscosity of oil extended EPDM ΔPHR: Oil extended amount per 100 parts by weight of EPDM

(2) Extrusion lamination, moldability: USV type 25 mmφ extruder manufactured by Union Plastics Co., Ltd. Full flight type screw, screw rotation speed 30 rpm, T die was used to mold a sheet of 0.5 mmt, and PPF (polypropylene foam) , Toray PPSM15030) and heat lamination to obtain a laminate.

(3) Oil bleeding property: 7
Let stand for 1 hour in an oven at 0 ° C and visually observe the oil bleeding on the surface of the molded product. The judgment rank is as follows. ○: No bleeding. Δ: There is slight bleeding. ×: There is bleeding.

(4) Heat Shrinkage The shrinkage after heating at 100 ° C. for 1 hour was measured.

Example 1 A mineral oil-based softening agent (Idemitsu Kosan Co., Ltd.) per 100 parts by weight of EPDM was added to a 5% by weight hexane solution of EPDM (ML _{1 + 4} 100 ° C. = 143, propylene content = 30% by weight, iodine value = 10). , Diana Process Oil PW-380) 40 parts by weight, and then desolvated by steam stripping 70 parts by weight of oil-extended EPDM (ML _{1 + 4} 100 ° C. = 53), polypropylene (MFR = 12 g / 10 min, Sumitomo) Noblene FL8013) (30 parts by weight) and Sumilizer BM (N, N'-m-phenylene bismaleimide, manufactured by Sumitomo Chemical Co., Ltd.) 0.2 parts by weight with a Banbury mixer.
After kneading at ˜200 ° C. for 7 minutes, pelletized master batch was prepared using an extruder. Then, 0.05 part by weight of 2,5-dimethyl-
2,5-di (t-butylperoxy) hexane (hereinafter,
It is described as "organic peroxide". Was uniformly blended for 10 minutes using a Henschel mixer. This blend is mixed with a twin-screw kneading extruder capable of obtaining a strong kneading force,
Dynamic heat treatment was performed at 0 ° C. ± 10 ° C. for 70 seconds and pelletized to obtain a thermoplastic elastomer composition. The obtained elastomer composition was subjected to extrusion lamination molding to obtain a laminate, and its physical properties were evaluated. The evaluation results are shown in Table 1.

Comparative Example 1 In the production of the masterbatch in Example 1, oil extension E
70 parts by weight of PDM is added to JSR EP-24 (ML _{1 + 4} 10
0 ° C. = 70, propylene content = 44% by weight, iodine value =
No. 12 EPDM, manufactured by Japan Synthetic Rubber Co., Ltd.) and 50 parts by weight of mineral oil type softener PW-380 and 20 parts by weight of the softening agent were used. The evaluation results are shown in Table 1.

[0037]

[Table 1]

[0038]

As described above, according to the present invention, it is possible to provide a laminate comprising a thermoplastic elastomer composition having extremely little oil bleed and excellent appearance and the like.

Claims (6)

[Claims] 1. A Mooney viscosity at 100 ° C. (ML _{1 + 4} 100
Oil-extended olefin-based copolymer rubber (A) 40 containing 20 to 150 parts by weight of a mineral oil-based softening agent per 100 parts by weight of an olefin-based copolymer rubber having a temperature of 120 to 350.
~ 95 wt% and propylene polymer resin (B) 5-60
A laminate comprising a thermoplastic elastomer composition, comprising a thermoplastic elastomer composition layer obtained by partially cross-linking a mixture consisting of 1% by weight and a polyethylene or polypropylene foam layer. 2. An olefin copolymer rubber is ethylene-based rubber.
The laminate according to claim 1, which is a propylene-non-conjugated diene rubber. 3. An ethylene-propylene-non-conjugated diene rubber is an ethylene-propylene-ethylidene norbornene copolymer rubber having a propylene content of 10 to 55% by weight and an ethylidene norbornene content of 1 to 30% by weight. Item 2. A laminate according to item 2. 4. An oil-extended olefinic copolymer rubber (A) 1
00 ℃ Mooney viscosity (ML _{1 + 4} 100 ℃) is 30-1
The laminated body according to claim 1, which is 00. 5. The laminate according to claim 1, wherein the propylene polymer resin (B) is polypropylene or a propylene-α-olefin copolymer resin. 6. The laminate according to claim 1, wherein the mineral oil softener is a paraffin softener.