JPH09208763A - Olefin-based polymer alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an olefin-based polymer alloy usable for nonsticky grade products of automotive internal trim articles with touch feeling as important characteristics. SOLUTION: This polymer alloy is composed of a crystalline polypropylene and a nonpolar thermoplastic elastomer as 1st and 2nd components, respectively, and an acrylate-styrene-acrylonitrile terpolymer as 3rd component, with the weight ratio of the 1st component to 2nd component being (10:90) to (90:10). And the amount of the 3rd component to be blended is 5-120 pts.wt. based on a total of 100 pts.wt. of the 1st and 2nd components.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polymer alloy containing a crystalline PP or crystalline PE and a non-polar TPE as the first and second components, respectively. In particular, the present invention relates to an olefin polymer alloy suitable as a molding material for a stickiness suppressing grade of automobile interior parts, in which the feel of steering wheel, armrest, shift lever knob, and assist grip (hereinafter referred to as steering wheel) is important.

[0002]

2. Description of the Related Art Recently, in interior parts for automobiles such as steering wheels, due to the tactile sensation (touch feeling),
It was formed of a material having a soft specification such as polyurethane (RIM urethane material) or polyvinyl chloride (soft PVC material) as a base, which can easily obtain a good feel.

However, these materials are difficult to recycle (recycle), and from the viewpoint of resource saving and environment, the emergence of alternative materials has been demanded.

That is, since the RIM urethane material is thermosetting, and the soft PVC material contains a large amount of plasticizer, and chlorine gas is generated by heating, which makes it impossible or difficult to recycle them. is there.

[0005]

Therefore, various studies and proposals have been made on whether or not an olefin polymer alloy represented by an olefin thermoplastic elastomer (olefin TPE) having good recyclability can be used as the alternative material. There is.

However, to the best of the knowledge of the present inventors, there is no known olefin polymer alloy that can be used as a stickiness suppressing grade for automobile interior parts where tactile sensation is important.

In view of the above, an object of the present invention is to provide an olefin polymer alloy which can be used as a stickiness suppressing grade for automobile interior parts in which tactile sensation is important.

[0008]

The olefin polymer alloy of the present invention solves the above problems by the following constitution.

(I) The olefin polymer alloy according to the first invention (claims 1 and 2) comprises crystalline PP and non-polar TPE.
In the polymer alloy having the respective first and second components, ASA is further blended as the third component, and the weight blending ratio of the first and second components is the former / the latter = 10/90. Is 90/10, and the compounding amount is 5-12 with respect to 100 parts by weight of the total amount of the first and second components of the third component.
It is characterized in that it is 0 part by weight.

(Ii) The olefin polymer alloy according to the second invention (claims 3 to 5) comprises crystalline PE and non-polar TPE.
In the polymer alloy having the respective first and second components, ASA is further blended as the third component, and the weight blending ratio of the first and second components is the former / the latter =
It is about 50/50 to 90/10, and the compounding amount is 5 to 12 with respect to 100 parts by weight of the total amount of the first and second components of the third component.
It is characterized in that it is 0 part by weight.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the constitution of the present invention will be described in detail. The blending units are weight units unless otherwise specified. In addition, Comparative Examples and Examples in parentheses are in Test Examples described later.

(1) The olefin polymer alloy of the present invention is a polymer alloy containing crystalline PP or crystalline PE and non-polar TPE as the first and second components, respectively,
Furthermore, the composition in which ASA is blended as the third component is a superordinate conceptual composition.

(2) The crystalline PP may be not only a polypropylene homopolymer but also a block copolymer with a small amount (usually 10% or less) of ethylene. The physical property is not particularly limited as long as it is crystalline, but the bending rigidity is usually 500 to 1500 MPa, and preferably 800 to 1
200 MPa and MFR 20-70 g / 10 minutes,
Desirably, 30 to 60 g / 10 minutes is used.

(3) The crystalline PE is not particularly limited, such as low density PE, linear low density PE, medium density PE and high density PE. In particular, Olsen rigidity (ASTM D747) 80-1
80 MPa, preferably 100 to 150 MPa, and MFR 10 to 40 g / 10 minutes, preferably 20 to 3
Use 0 g / 10 minutes.

(4) EPR and SB as non-polar TPE
C, an olefinic TPE, etc. can be mentioned.

The EPR is an amorphous ethylene / propylene copolymer or an amorphous ethylene / propylene / non-conjugated copolymer, which may be partially crosslinked if necessary. The physical properties are not particularly limited, but usually Mooney viscosity (ML _{1 + 4} 100 ° C.) 10 to 50, preferably 2
Those having an MFR of 0 to 30 and having an MFR of 1 to 10 g / 10 minutes, preferably 2 to 5 g / 10 minutes are used.

As SBC, polystyrene (PS) -polyisoprene-PS structure SIS), PS-polybutadiene-PS structure SBS, and hydrogenated products thereof, P
S-Polyethylene / Polybutylene (Polyhexene) -P
S, etc. can be mentioned.

As the olefin-based TPE, polypropylene blended with EPR, those partially crosslinked with an organic peroxide, and the rubber phase dispersed at the time of kneading are completely crosslinked (dynamic vulcanization). It is possible to use those that have been made.

(3) ASA is basically an acrylate.
Each unit content of (a), styrene (b), and acrylonitrile (c) is usually (a) / (b) / (c) = 50/25 / 25-
90/5/5, desirably 60/20/20 to 80 /
10/10, and the hardness of the molded product (JIS A) is 40 to 8
0, preferably 50-70.

Here, butyl acrylate is essential as the acrylate (acrylic acid ester), but butyl acrylate may be replaced with 2-ethylhexyl acrylate of about 40% or less, and further methyl. 40% or less, preferably 10 to 30% of ethyl (meth) acrylate based on the whole acrylate component
It is desirable to include it.

The above ASA is synthesized by radical polymerization using a conventional emulsion polymerization system. The synthesis can be carried out by the following method described in US Pat. No. 5,380,785.

"(I) (i) butyl acrylate (substitutable with 2-ethylhexyl acrylate in a range of 40 mol% or less), (ii) at least one acrylate selected from methyl ethyl (meth) acrylate, (iii) ) Acrylonitrile, (iv) Crosslinking agent (polyfunctional acrylate),
And (v) a step of synthesizing a mixture of maleate higher fatty acid monoesters by an emulsion polymerization method to form a core polymer containing a latex, and (II) further comprising (i) styrene, (ii) residual acrylonitrile, and (iii) a residue. Adding a crosslinking agent to the core polymer to synthesize an emulsion containing a rubber polymer,
(III) a step of recovering a rubber polymer from the emulsion. (4) The compounding ratio of each of the above components is as follows.

In the case of the first invention, the compounding ratio of the first and second components (crystalline PP / amorphous TPE) is 10/90.
~ 90/10, preferably 20/80 to 80/20,
More preferably, it is 60/40 to 80/20.

In the case of the second invention, the compounding ratio of the first and second components (crystalline PE / amorphous TPE) is about 50/5.
0 to 90/10, preferably 60/40 to 80/20
It is.

The compounding amount of the third component (ASA) with respect to the total amount of 100 parts of the first and second components is 10 to 120 parts (desirably 20 to 110 parts).

When the ASA is too small, it is difficult to obtain the effect of suppressing stickiness of the molded article, which is the effect of the present invention. On the other hand, ASA
If the amount is too large, the compatibility between ASA and other component polymers in the molded product decreases, and the physical properties of the molded product are likely to be adversely affected.

It should be noted that the above-mentioned olefin-based polymer alloy may be added to other poly (di) polymers within a range not impairing the object of the present invention.
Olefins, for example, butene hexene heptene
Homo-copolymers such as isoprene-butadiene can be added as the fourth, fifth,... Components.

(B) Preparation of molding material / molded product: (1) The olefin polymer alloy of the present invention comprises the above-mentioned components, namely crystalline PP (or crystalline PE), non-polar TPE, and ASA, With other polyolefins as needed, other, lubricants, softeners, inorganic fillers, colorants,
Add materials such as heat stabilizers, antioxidants, UV absorbers, anti-aging agents, etc. as needed, mix them, and then heat-treat them dynamically to use as injection molding or extrusion molding materials. .

Here, the dynamic heat treatment means kneading in a molten state. The dynamic heat treatment is preferably performed in a non-open type device such as a Banbury mixer, a kneader, a single screw extruder or a twin screw extruder, and is preferably performed in an inert gas such as nitrogen. The kneading temperature is usually 250 ° C. from the melting point of the polyolefin resin.
The kneading time is desirably 1 to 10 minutes.

The shearing force applied at the time of kneading is preferably in the range of 100 to 10,000 sec ^-1 at a normal shearing rate.

Examples of the lubricant / softener include the following.

Silicone oils such as dimethyl silicone and methylphenyl silicone; process oils, lubricating oils, paraffin, liquid paraffin, petroleum asphalt,
Petroleum-based substances such as petrolatum; coal tars such as coal tar and coal tar pitch; fatty oils such as castor oil, linseed oil, rapeseed oil, soybean oil, and coconut oil; tall oil, beeswax,
Waxes such as carnauba wax and lanolin; ricinoleic acid,
Fatty acids such as palmitic acid and stearic acid or metal salts thereof; synthetic polymers such as petroleum resin, coumarone indene resin, atactic polypropylene; dioctyl phthalate,
Ester plasticizers such as dioctyl adipate and dioctyl sebacate; other microcrystalline waxes;
Liquid polybutadiene or a modified or hydrogenated product thereof,
And liquid thiochol.

As the above-mentioned inorganic filler, specifically,
Calcium carbonate, calcium silicate, clay, kaolin,
Examples include talc, silica, diatomaceous earth, mica powder, asbestos, barium sulfate, aluminum sulfate, calcium sulfate, magnesium carbonate, molybdenum disulfide, glass fiber, glass sphere, shirasu balloon, graphite, and alumina.

(2) Preparation of molded product The steering wheel is manufactured, for example, by a known injection molding method.

For example, in a steering wheel having a skin material having a textured pattern formed on its surface, a wheel core metal is placed in a mold having a textured pattern formed on its surface, and the molding material is placed in the mold. It can be manufactured by injecting and cooling and solidifying.

[0036]

EFFECT OF THE INVENTION The olefin polymer alloy according to the present invention, as will be shown in Examples described later, does not deteriorate the compatibility of the polymers with each other, that is, while maintaining good physical properties, it is a molding which is suppressed in stickiness. Goods can be prepared.

The olefin polymer alloy of the present invention is
It can be used as a molding material for stickiness suppressing grade of automobile interior parts where tactile sensation is important, can be recycled, and contributes to resource and energy saving as well as to the environment.

[0038]

EXAMPLES Examples and comparative examples performed to confirm the effects of the present invention will be described below.

(1) The components of the olefin polymer alloys used in Examples and Comparative Examples are shown below.

Crystalline PP Bending rigidity: 1009 MPa MFR: 45 g / 10 min Density (d): 0.90 g / cm ³ Crystalline PE (low density PE) Olsen rigidity: 120 MPa MFR: 23 g / 10 min Density (d): 0.92 g / cm ³ EPR (ethylene propylene copolymer rubber) Mooney viscosity (ML _{1 + 4} 100 ° C.) 24 MFR: 3.2 g / 10 min Ethylene content: 74 wt% SBC (SEBS) hardness (JIS A): 65 MFR: 8 g / 10 min Styrene content: 13 wt% ASA Acrylate content: 70% Styrene content: 15% Acrylonitrile content: 15% Hardness (Shore A): 53 MFR: 2.5 g / 10 min Mooney viscosity (ML _{1 + 4} 100 ℃): 44 (2) After thoroughly stirring and mixing the mixture of the formulations shown in Tables 1 and 2 in a Henschel mixer, to 220 ℃ Kneaded through boss was a twin-screw extruder having a screw diameter of 30 mm, each of the embodiments,
A molding material (pellet) made of the olefin polymer alloy of the comparative example was manufactured.

Using the molding materials of the examples and comparative examples,
The following items were tested.

The injection molding conditions are as follows.

Molding conditions: Cylinder temperature: 220 ° C., mold temperature: 40 ° C., injection pressure: 38 MPa 1) Sticky organoleptic evaluation (normal temperature) Feeling when a test piece (40 mm × 110 mm × 2 mmt) was traced with a finger, It was evaluated by several panelists. These evaluations were performed at 20 ° C. (normal temperature) and 30 ° C., and were determined by consultation between panelists. The evaluation criteria are as follows.

5: Does not feel sticky (pass).

4 ... Slightly sticky (pass).

3 ... Feels slightly sticky (fail).

2 ... Clearly sticky (fail).

1 ... Remarkably sticky (failed).

2) Quantitative evaluation of stickiness (peel strength) The test pieces described above were piled up, and 75 mm × 150 mm × 2 mmt
Is made by press molding.

Saran wrap was pressed by a cold press at a pressure of 30 kgf / cm ² (2.9 MPa) for 1 minute for pressure bonding.

A tape was attached to this wrap, the peel strength was measured, and the stickiness (tackiness) was evaluated. 3) Compatibility Evaluation The corners of the sheet prepared in 2) above were bent and the state was observed. The judgment criteria are shown below.

4: No change (pass) 3: Slightly whitening of folds (pass) 2: Whitening of folds is remarkable, cracks and the like occur (fail) 1: Break at folds (fail) (3) The test results are shown in Table 1. It can be seen that the injection-molded articles of each of the examples satisfying the requirements of the present invention have good compatibility of each component polymer and suppress stickiness. In particular, Examples 1 and 2 in which the first component is 60 or more
It can be seen that 3 and 5 and 6 have a great effect of suppressing stickiness.

Comparative Example 1 containing no third component (ASA)
・ 3, 4, 7, and 9 are sensory in the stickiness test.
It can be seen that the stickiness suppressiveness is not sufficient in both the quantitative evaluations. Comparative Example 2.8 in which the third component (ASA) is excessive
Shows that the polymer compatibility is not good.

The second component (non-polar T
Comparative Examples 5 and 10 not containing PE) did not have good polymer compatibility, and Comparative Example 1 in which the first component was crystalline PE
0 indicates that the stickiness suppressive action is not sufficient in the quantitative evaluation.

The first and second components (crystalline P
It can be seen that Comparative Examples 6 and 11 not containing P.PE) do not have sufficient stickiness suppression in both sensory and quantitative evaluations.

[0056]

[Table 1]

[0057]

[Table 2]

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display area C08L 53/02 LLY C08L 53/02 LLY

Claims (4)

[Claims] 1. A crystalline polypropylene (hereinafter referred to as "crystalline P
Abbreviated as "P". ) And a nonpolar thermoplastic elastomer (hereinafter abbreviated as “nonpolar TPE”) as the first and second components, respectively, and as the third component, an acrylate / styrene / acrylonitrile terpolymer ( Hereinafter abbreviated as "ASA".)
And the weight mixing ratio of the first and second components is such that the former / the latter = 10.
/ 90 to 90/10, and the compounding amount is 5 to 120 parts by weight based on 100 parts by weight of the total amount of the first and second components of the third component. 2. An ethylene propylene elastomer (hereinafter abbreviated as “EPR”) and a styrene thermoplastic elastomer (hereinafter abbreviated as “SBC”) as the second component.
The olefin-based polymer alloy according to claim 1, wherein one kind or two or more kinds is selected from the above. 3. Crystalline polyethylene (hereinafter referred to as "crystalline P
Abbreviated as "E". ) And a non-polar thermoplastic elastomer as the first and second components, respectively, and as the third component, an acrylate / styrene / acrylonitrile terpolymer (hereinafter abbreviated as “ASA”).
In the composition, the weight mixing ratio of the first and second components is such that the former / the latter = approximately 5
The olefin-based polymer alloy is 0/50 to 90/10, and the compounding amount is 5 to 120 parts by weight based on 100 parts by weight of the total amount of the first and second components of the third component. 4. One or more types are selected from the ethylene-propylene elastomer (hereinafter abbreviated as “EPR”) and the styrene elastomer (hereinafter abbreviated as “SBC”) as the second component. Item 5. The olefin polymer alloy according to Item 3.