JP2000053808A - Softener-containing elastomer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a softener-containing elastomer composition having a good processibility, flexibility and mechanical properties by allowing a polymer comprising an elastomer and a thermoplastic resin to contain a large amount of a softener. SOLUTION: This composition comprises (A) 1 to 99 pts.wt. crosslinked elastomer, (B) 1 to 99 pts.wt. thermoplastic resin [the total of (A) and (B) is 100 pts.wt.], (C) 1 to 500 pts.wt. softener and (D) 0.0001 to 100 pts.wt. organic acid polyvalent metal salt and is partially or completely crosslinked. Furthermore, (E) an organic acid is preferably mixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a softener-containing elastomer composition. More specifically, the present invention relates to a softener-containing elastomer composition which enables a large amount of a softener to be added to a polymer composed of an elastomer and a thermoplastic resin, and as a result, has excellent processability, flexibility and mechanical properties.

[0002]

2. Description of the Related Art Polymers such as thermoplastic resins and elastomers have excellent mechanical properties such as heat resistance and impact resistance, and are used in various fields such as automotive materials, electric materials and housing materials. It is used. In recent years, a softener such as liquid paraffin (mineral oil) has been added in such a field in order to improve processability and flexibility of the material. At that time, in order to impart a high degree of the above function to the polymer, it is necessary to add as much softener as possible,
When the compatibility between the polymer and the softener is not good, there is a problem that the softener bleeds.

To solve this problem, the present inventor has made it possible to maintain a large amount of a softening agent in a polymer by using an organic acid polyvalent metal salt as an essential component and blending an organic acid as necessary. I found it. On the other hand, a method for recovering oils by adding a liquid organic acid to a gelled oil obtained by gelling oils with aluminum 2-ethylhexanoate (Japanese Patent Application Laid-Open No. 10-183108), liquid oils and fats of aluminum 2-ethylhexanoate and unsaturated fatty acids Dispersant for gelling (Japanese Unexamined Patent Publication No. 9-31)
No. 6436), a method of treating fats and oils in which an aqueous solution of aluminum sulfate, an aqueous solution of aluminum chloride and an aqueous solution of sodium 2-ethylhexanoate are mixed and reacted to form aluminum 2-ethylhexanoate in the presence of oils (Japanese Patent Application Laid-Open No. 9-316437). JP-A-9-2), an oil dispersant containing hydrated aluminum n-octanoate or hydrated aluminum 2-ethylhexanoate as an active ingredient.
No. 53656) is disclosed. Although the above-mentioned publication uses an organic acid polyvalent metal salt, it is a method for recovering or treating oils, and a composition capable of holding a large amount of a softening agent in a polymer is not disclosed or even implied. Not.

[0004]

SUMMARY OF THE INVENTION In view of the above situation, the present invention does not have the above-mentioned problems, that is, not only facilitates the handling of the softener, but also adds a large amount of the softener to the polymer. To be added, resulting in excellent processability,
An object of the present invention is to provide a softener-containing elastomer composition having flexibility and mechanical properties.

[0005]

The present inventors have intensively studied a softener-containing elastomer composition having improved processability and flexibility, and found that a partially or completely cross-linked polymer and a softener were used. The organic acid polyvalent metal salt as an essential component, by blending an organic acid as needed, surprisingly found that a large amount of softener is retained in the composition,
The present invention has been reached.

That is, the present invention provides (A) 1 to 99 parts by weight of a crosslinkable elastomer, (B) 1 to 99 parts by weight of a thermoplastic resin [the total amount of (A) and (B) is 100 parts by weight],
A partially or completely crosslinked softener-containing elastomer composition comprising (C) 1 to 500 parts by weight of a softener and (D) 0.0001 to 100 parts by weight of an organic acid polyvalent metal salt, and more preferably (E). It is intended to provide a softener-containing elastomer composition containing an organic acid.

Hereinafter, the present invention will be described in detail. The composition of the present invention comprises (A) a crosslinkable elastomer, (B) a thermoplastic resin, (C) a softening agent, (C) a polyvalent metal salt of an organic acid, and if necessary, (D) an organic acid. (A) and (B) above
The polymer of (A) plays a role of maintaining the strength of a molded article obtained from the composition, and (C) has processability in (A) and (B).
It is a component for controlling the surface hardness, and (D) and (E) are components for absorbing and retaining (C).

In the present invention, when (C) is a softening agent such as paraffin oil and (D) is an organic acid aluminum salt such as aluminum 2-ethylhexanoate,
The present invention has been found to show excellent absorption-retaining properties of a softening agent and to exhibit excellent absorption-retaining properties when an organic acid such as stearic acid is used in combination as (E).

Hereinafter, each component of the present invention will be described in detail. In the present invention, (A) the crosslinkable elastomer comprises:
For example, polystyrene, polyolefin, polyester, polyurethane, 1,2-polybutadiene,
It is a polyvinyl chloride type or the like, and particularly preferably a polyolefin type thermoplastic elastomer.

Among the above-mentioned polyolefin-based thermoplastic elastomers, ethylene / α-olefin copolymer rubber is particularly preferable, for example, ethylene and carbon number 3-20.
More preferably, an ethylene / α-olefin copolymer rubber comprising 6 to 12 α-olefins is exemplified. Examples of the α-olefin having 3 to 20 carbon atoms include propylene, butene-1, pentene-1, hexene-1,
4-methylpentene-1, heptene-1, octene-
1, nonene-1, decene-1, undecene-1, dodecene-1 and the like. Among them, hexene-1, 4-methylpentene-1 and octene-1 are preferred, and octene-1 is particularly preferred. Octene-1 is excellent in softening effect even in a small amount, and the obtained copolymer is excellent in mechanical strength.

One polyolefin elastomer (A) preferably used in the present invention is preferably produced using a known metallocene catalyst. Generally, a metallocene-based catalyst is composed of a cyclopentadienyl derivative of a group IV metal such as titanium or zirconium and a co-catalyst, and is not only highly active as a polymerization catalyst, but also has a higher polymer yield than a Ziegler-based catalyst. Is the most preferable because the distribution of α-olefins having 3 to 20 carbon atoms as a comonomer in the copolymer is uniform.

One polyolefin elastomer (A) preferably used in the present invention preferably has an α-olefin copolymerization ratio of 1 to 60% by weight, more preferably 10 to 50% by weight, Most preferably 20 to
45% by weight. α-olefin copolymerization ratio is 60
When the content is more than 1% by weight, the hardness, tensile strength, etc. of the composition are greatly reduced, while when the content is less than 1% by weight, the hardness of the composition is high,
The mechanical strength tends to decrease.

The density of one polyolefin elastomer (A) is preferably in the range of 0.8 to 0.9 g / cm ³ . By using a polyolefin elastomer having a density in this range, excellent flexibility,
A thermoplastic elastomer composition having low hardness can be obtained. The polyolefin-based elastomer used in the present invention preferably has a long-chain branch. Due to the presence of the long-chain branching, without lowering the mechanical strength, compared to the ratio (% by weight) of the copolymerized α-olefin,
The density can be further reduced, and a low-density, low-hardness, high-strength elastomer can be obtained. As an olefin elastomer having a long chain branch, USP
5278272 and the like.

Further, the polyolefin-based elastomer is
It is desirable to have a melting point peak of DSC above room temperature. When it has a melting point peak, the form is stable in the temperature range below the melting point, the handleability is excellent, and the stickiness is small. Further, the melt index of the polyolefin-based elastomer used in the present invention is 0.01 to 100 g.
/ 10 minutes (190 ° C., 2.16 kg load) are preferably used, and more preferably 0.2 to 10 g / min.
10 minutes. If the amount exceeds 100 g / 10 minutes, the crosslinking property of the thermoplastic elastomer composition is insufficient, and the crosslinking rate of the thermoplastic elastomer composition is too low.
If it is less than 01 g / 10 minutes, the fluidity is poor and the processability is undesirably reduced.

In the present invention, the thermoplastic resin (B) is preferably an olefin-based resin, particularly preferably a propylene-based resin, and more specifically, homoisotactic polypropylene, propylene and ethylene, butene-1, pentene-1. Copolymer resin with other α-olefins such as hexene-1 and hexene-1 (including block and random)
And the like.

Further, the melt index of the propylene resin in (B) used in the present invention is 0.1 to 1
Those having a range of 00 g / 10 minutes (230 ° C., 2.16 kg load) are preferably used. If it exceeds 100 g / 10 minutes, the heat resistance and mechanical strength of the thermoplastic elastomer composition will be insufficient, and if it is less than 0.1 g / 10 minutes, the fluidity will be poor and the moldability will be reduced, which is not desirable. .

In the present invention, the total of (A) and (B) is 1
In (00) parts by weight, (A) is used in a composition ratio of 1 to 99 parts by weight. Preferably 5 to 90 parts by weight, more preferably 2
0 to 80 parts by weight, most preferably 20 to 70 parts by weight. If the amount is less than 1 part by weight, the fluidity and processability of the composition are reduced, and if it exceeds 99 parts by weight, the flexibility of the composition is insufficient, which is not desirable.

The elastomer composition provided by the present invention needs to be partially cross-linked by a radical initiator such as an organic peroxide or a radical initiator and a crosslinking aid. This further improves wear resistance and mechanical strength,
Heat resistance and the like can be improved. Here, as a specific example of a preferably used radical initiator,
1,1-bis (t-butylperoxy) -3,3,5-
Trimethylcyclohexane, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) ) Cyclododecane, 1,1-bis (t-butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) octane, n-butyl-4,4-bis (t-butylperoxy) butane, Peroxy ketals such as n-butyl-4,4-bis (t-butylperoxy) valerate; di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, α, α′-bis (T-butylperoxy-m-isopropyl) benzene, α, α′-bis (t-butylperoxy) diisopropylbenzene, 2,5-di Methyl-2,5-bis (t
-Butylperoxy) hexane and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3
Dialkyl peroxides such as acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, and 2,4- Diacyl peroxides such as dichlorobenzoyl peroxide and m-trioyl peroxide; t-butylperoxyacetate, t-butylperoxyisobutyrate, t-butylperoxy-2-ethylhexanoate, t-butyl Peroxylaurate, t-butylperoxybenzoate, di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxymaleic acid, t-butylperoxymaleate Peroxyesters such as tilperoxyisopropyl carbonate and cumylperoxyoctate; and t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5- Hydroperoxides such as dihydroperoxide and 1,1,3,3-tetramethylbutyl peroxide can be exemplified.

Among these compounds, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl -2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3 are preferred.

These radical initiators are used in an amount of 0.01 to 3 with respect to 100 parts by weight of the polymer comprising (A) and (B).
It is used in amounts of parts by weight, preferably 0.02 to 1 part by weight. If the amount is less than 0.01 part by weight, the crosslinking is insufficient, and if it exceeds 3 parts by weight, the physical properties of the composition are not improved, which is not preferable. Further, as a crosslinking aid, divinylbenzene, triallyl isocyanurate, triallyl cyanurate, diacetone diacrylamide, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diisopropenylbenzene, P- quinone dioxime, P, P ^'- dibenzoyl quinone dioxime, phenylmaleimide, allyl methacrylate, N, ^N'-m-
Phenylene bismaleimide, diallyl phthalate, tetraallyloxyethane, 1,2-polybutadiene and the like are preferably used. These crosslinking aids may be used in combination of two or more.

These crosslinking assistants are used in an amount of 0.1 to 5 parts by weight, preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the polymer comprising (A) and (B). If the amount is less than 0.1 part by weight, crosslinking is insufficient, and if it exceeds 5 parts by weight, the physical properties of the composition are not improved, and an excessive amount of a crosslinking aid remains, which is not preferable. As a specific example, the elastomer composition of the present invention can be produced through the following processing steps. For example, an olefin-based elastomer and a propylene-based resin are mixed well and then charged into a hopper of an extruder. The radical initiator and the crosslinking assistant may be added together with the olefin-based elastomer and the propylene-based polymer from the beginning, or may be added in the middle of the extruder. The oil may be added from the middle of the extruder, or may be added separately at the beginning and during the middle. The olefin-based elastomer and the propylene-based resin may be partially added in the middle of the extruder.
When heated and melted and kneaded in an extruder, the elastomer and the radical initiator and the crosslinking auxiliary undergo a crosslinking reaction, and the crosslinking reaction and kneading dispersion are sufficiently performed by further adding and melting oil and kneading. Then remove from the extruder.
Pellets can be obtained to obtain pellets of the elastomer composition of the present invention.

The degree of cross-linking as a measure of the cross-linkability of the elastomer composition of the present invention is preferably at least 30%, more preferably at least 50%. If it is less than 30%, the crosslinking is insufficient, and the physical properties are reduced. The degree of crosslinking was determined by refluxing 0.5 g of the elastomer composition in 200 ml of xylene for 4 hours, filtering the solution through a filter paper for quantification, drying the residue on the filter paper in vacuo, quantifying the residue, and determining the residue relative to the weight of the elastomer in the composition. Expressed as a weight ratio of The softener used as (C) in the present invention is a component for controlling processability and flexibility (surface hardness) of the polymer comprising (A) and (B), and has a viscosity at 25 ° C. Preferably, it is less than 100,000 centistokes.

The amount of (C) is 1 to 500 parts by weight based on 100 parts by weight of the composition comprising (A) and (B).
Preferably 1 to 250 parts by weight, more preferably 10 to 1 part
It is 50 parts by weight, more preferably 20 to 100 parts by weight, most preferably 30 to 70 parts by weight. Examples of the softening agent include paraffinic and naphthenic process oils, phthalic acid esters such as dimethyl phthalate, diethyl phthalate and diisobutyl phthalate, phthalic acid mixed ester such as butyl benzyl phthalate, and succinic acid. Aliphatic dibasic acid esters such as diisodecyl and dioctyl adipate; glycol esters such as diethylene glycol dibenzoate; butyl oleate; acetyl ricino-
Aliphatic acid esters such as methyl luate, epoxidized soybean oil,
Epoxy plasticizers such as epoxidized linseed oil, and others, trioctyl trimellitate, ethyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate,
Tributyl acetyl citrate, chlorinated paraffin, polypropylene adipate, polyethylene sebacate, triacetin, tributyrin, toluenesulfonamide, alkylbenzene, biphenyl, partially hydrogenated terphenyl,
Camphor and the like can be mentioned. Among the above softeners, process oils such as paraffinic and naphthenic are most preferred.

The (D) organic acid polyvalent metal salt according to the present invention may be a carboxylic acid or a sulfonic acid 2A, 2B, 3B, 3
A salt of a metal element selected from the groups A, 4A, 5A, 6A, 7A, 8, and 8 is preferable, and aluminum as a metal element is most preferable. Among the above (C), a polyvalent metal salt of a higher aliphatic carboxylic acid is particularly preferable, and a saturated monocarboxylic acid is particularly preferable. For example, polyvalent metal salts such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid and montanic acid can be mentioned, among which aluminum 2-ethylhexanoate is most preferred.

The amount of (D) is 0.0001 to 100 parts by weight, preferably 0.001 to 50 parts by weight, more preferably 100 to 100 parts by weight of the composition comprising (A) and (B). Is 0.01 to 30 parts by weight, more preferably 0.1 to 30 parts by weight.
20 parts by weight, most preferably 1 to 10 parts by weight. As the organic acid (E) in the present invention, the organic acid used in the above (D) is useful, and a higher monocarboxylic acid is particularly preferable. Among them, oleic acid or stearic acid is most preferable.

The amount of (E) is from 0 to 100 parts by weight based on 100 parts by weight of the composition comprising (A) and (B).
Preferably 0.001 to 50 parts by weight, more preferably 0.1 to 50 parts by weight.
The amount is from 01 to 30 parts by weight, more preferably from 0.1 to 20 parts by weight, most preferably from 1 to 10 parts by weight. The composition of the present invention can contain an inorganic filler to the extent that its characteristics are not impaired. As the inorganic filler used here, for example, calcium carbonate, magnesium carbonate,
Silica, carbon black, glass fiber, titanium oxide,
Clay, mica, talc, magnesium hydroxide, aluminum hydroxide and the like. Also, other additives,
For example, organic / inorganic pigments, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, flame retardants, silicone oils, antiblocking agents, foaming agents, antistatic agents, antibacterial agents and the like are also suitably used.

[0027]

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In these examples and comparative examples, the test methods used for evaluating various physical properties are as follows. (1) Surface Hardness Four sheets having a thickness of 2 mm were piled up and evaluated according to ASTM D2240 using an A type in a 23 ° C. atmosphere. The lower the number, the higher the flexibility. (2) Tensile breaking strength [kgf / cm ² ] Evaluated at 23 ° C. according to JIS K6251. (3) Tensile elongation at break [%] Evaluated at 23 ° C. according to JIS K6251.
(4) Compression set (C-set) [%] Evaluated at 70 ° C. for 22 hours according to JIS K6301. The smaller the value, the better the compression set. (5) Oil Bleed The sample immediately after molding was left for one week in an environment of 23 ° C, and the condition of the oil that had emerged on the surface was visually evaluated on the following scale.

：: No oil bleed Δ: Slightly present X: Clearly present The following components were used in Examples and Comparative Examples. (A) Crosslinkable elastomer Copolymer of ethylene and octene-1 It was produced by a method using a metallocene catalyst described in JP-A-3-1630088. The ethylene / octene-1 composition ratio of the copolymer is 72/28 (weight ratio).
(Referred to as TPE) (b) Thermoplastic resin polypropylene Isotactic polypropylene (referred to as PP) manufactured by Nippon Polychem Co., Ltd. (c) Aluminum 2-ethylhexanoate While stirring an aqueous solution of 2-ethylhexanoate and an aqueous solution of aluminum sulfate at room temperature The mixture was reacted, filtered, washed with water, and dried to obtain aluminum 2-ethylhexanoate. (D) Stearic acid Stearic acid (referred to as SA) manufactured by Wako Pure Chemical Industries, Ltd. (E) Paraffin oil Diana Process Oil PW-3 manufactured by Idemitsu Kosan Co., Ltd.
80 (referred to as MO) (f) Radical initiator 2,5-dimethyl-2,5-bis (t-manufactured by NOF Corporation)
Butylperoxy) hexane (trade name Perhexa 25)
B) (referred to as POX) (g) Crosslinking auxiliary divinylbenzene (referred to as DVB) manufactured by Wako Pure Chemical Industries, Ltd.

[0029]

Examples 1-2 and Comparative Examples 1-2 A twin-screw extruder (40 mmφ, L / L) having an injection port at the center of the barrel was used as an extruder.
D = 47) was used. As the screw, a double screw having a kneading portion before and after the injection port was used. After mixing at the composition ratios shown in Table 1, the mixture was introduced into a twin-screw extruder (cylinder temperature: 220 ° C.) to perform melt extrusion. However, for the composition using MO, after mixing other than MO, the mixture is introduced into a twin-screw extruder (cylinder temperature 220 ° C.), and then a predetermined amount of MO is injected by a pump from an injection port at the center of the extruder. Then, melt extrusion was performed.

From the composition thus obtained, 200
A sheet having a thickness of 2 mm was prepared by compression molding at ℃, and each mechanical property and oil bleeding property were evaluated. Table 1 shows the results.

[0031]

[Table 1]

According to Table 1, when a polyvalent metal salt of an organic acid is added, the retention of a softener is improved, but when an organic acid is used in combination, excellent retention of a softener and excellent mechanical properties are exhibited. You can see that

[0033]

The composition of the present invention enables a polymer comprising an elastomer and a thermoplastic resin to contain a large amount of a softening agent, and as a result, has excellent processability, flexibility, mechanical properties and the like. The composition of the present invention can be used for automotive parts, automotive interior materials, airbag covers, mechanical parts, electrical parts, cables, hoses, belts, toys, miscellaneous goods, daily necessities, building materials, sheets, films, and other applications. It can be used widely and plays a large role in the industrial world.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 AC04W AE05Y AF03Y BB05W BB13X BB15W BB15X BB16W BB17W BB17X BC05W BD05W BP02X CD16Y CF00W CF28Y CK02W EA016 EC037 EC047 EF038 FD0E FD 016E FD

Claims (5)

[Claims] (A) 1 to 99 parts by weight of a crosslinkable elastomer, (B) 1 to 99 parts by weight of a thermoplastic resin (the total amount of (A) and (B) is 100 parts by weight), and (C) a softener. 1 to
500 parts by weight, and (D) an organic acid polyvalent metal salt 0.00
A partially or completely crosslinked softener-containing elastomer composition comprising from 01 to 100 parts by weight. 2. The softener-containing elastomer composition according to claim 1, further comprising (E) an organic acid. 3. The softener-containing elastomer composition according to claim 2, wherein (E) is stearic acid. 4. The softener-containing elastomer composition according to claim 1, wherein (D) is an organic acid aluminum salt. 5. The softener-containing elastomer composition according to claim 4, wherein (D) is aluminum 2-ethylhexanoate.