JP2006002065A - Thermoplastic elastomer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition which is imparted with excellent weatherability and shape-retaining properties at high temperatures without reducing moldability of a vinyl chloride-based resin composition. <P>SOLUTION: The thermoplastic elastomer composition is obtained by kneading 100 pts. mass of a vinyl chloride-based resin (A), 20-200 pts. mass of a plasticizer (B), and 1-200 pts. mass of an unsaturated carboxylic acid ester-based copolymer (C). The vinyl chloride-based resin (A) preferably has an average polymerization degree of 800-4,000. The unsaturated carboxylic acid ester-based copolymer (C) may be a copolymer of an ethylene unit and/or a vinyl acetate unit, or may further contain 0.01-20 pts. mass of a crosslinking agent (D) based on 100 pts. mass of the unsaturated carboxylic acid ester-based copolymer (C). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a thermoplastic elastomer composition, and more particularly to a thermoplastic elastomer composition excellent in weather resistance and shape retention at high temperatures.

  Vinyl chloride resin compositions containing plasticizers are widely used as materials for building material gaskets such as window frames and automobile gaskets such as belt moldings, window moldings and side moldings. The composition has a problem that the shape retention at a high temperature and the compression set characteristic are remarkably inferior to the vulcanized rubber.

In order to solve these problems, an organic peroxide compound is added to a thermoplastic elastomer composition having a vinyl chloride resin, a plasticizer, and a partially crosslinked nitrile rubber, and the partially crosslinked nitrile rubber is dynamically changed during molding processing. There is known a means for cross-linking (see, for example, Patent Document 1).
However, since the composition obtained by this means contains a partially crosslinked nitrile rubber in the resin composition, there is a problem that coloring and deterioration of physical properties may occur when used outdoors.
JP-A-8-225699

  Then, this invention makes it a subject to provide the thermoplastic elastomer composition excellent in the weather resistance and the shape retention at high temperature.

  As a result of various studies to solve the above problems, the present inventors have added a specific unsaturated carboxylic acid ester copolymer to the vinyl chloride resin composition, thereby improving weather resistance and high temperature. The present inventors have found that a thermoplastic elastomer composition excellent in shape-retaining property can be obtained.

  That is, in the present invention, 100 parts by mass of vinyl chloride resin (A), 20 to 200 parts by mass of plasticizer (B), and 1 to 200 parts by mass of unsaturated carboxylic acid ester copolymer (C) are kneaded. It relates to the thermoplastic elastomer composition obtained.

Hereinafter, the present invention will be described in detail. In the present invention, units such as “part” representing the ratio of the resin composition and the like and “%” representing the composition ratio of the monomer in the resin are represented on a mass basis unless otherwise specified.
The vinyl chloride resin (A) is obtained by subjecting a mixture of vinyl chloride and a vinyl compound copolymerizable with vinyl chloride to a usual method such as a suspension polymerization method, a bulk polymerization method, a fine suspension polymerization method or an emulsion polymerization method. Examples thereof include a polymerized resin composition, and a resin obtained by graft-copolymerizing vinyl chloride to an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, chlorinated polyethylene, or the like. Further, a chlorinated vinyl chloride resin may be used.

  Examples of vinyl compounds copolymerizable with vinyl chloride include vinyl esters such as vinyl acetate and vinyl propionate, acrylic acid esters such as methyl acrylate and butyl acrylate, methacrylic acid esters such as methyl methacrylate and ethyl methacrylate, and butyl maleate. And maleic esters such as diethyl malate, fumaric esters such as dibutyl fumarate and diethyl fumarate, vinyl ethers such as vinyl methyl ether, vinyl butyl ether and vinyl octyl ether, vinyl cyanides such as acrylonitrile and methacrylonitrile , Α-olefins such as ethylene, propylene and styrene, vinylidene halides and vinyl halides other than vinyl chloride such as vinylidene chloride and vinyl bromide, and diallyl phthalate Phthalic acid esters such as bets and the like.

  The average degree of polymerization of these vinyl chloride resins is preferably 800 to 4000, more preferably 1200 to 3600, and more preferably 1500 to 2700, as measured by JIS K6720-2. Most preferred. When the degree of polymerization is less than 800, the molded article of the thermoplastic elastomer composition obtained has poor shape retention at high temperatures, and when it exceeds 4000, the obtained thermoplastic elastomer composition is melted during molding. There is a possibility that the viscosity becomes remarkably high and molding processability is deteriorated.

  The plasticizer (B) is an organic compound for imparting plasticity such as flexibility and flexibility to the vinyl chloride resin (A), and can be used without particular limitation as long as it can be used for the vinyl chloride resin. . Examples of the plasticizer (B) include phthalates such as di-2-ethylhexyl phthalate and dibutyl phthalate, adipates such as di-2-ethylhexyl adipate, sebacates such as dibutyl sebacate, tri 2-ethylhexyl trimellitate and other trimellitic acid esters, pyromellitic acid esters, aliphatic dibasic acid esters, glycol esters, fatty acid esters, phosphate esters, citrate ester plasticizers, and epoxy plastics Agents, polyester plasticizers, and the like, and one or a mixture of these can be used.

  The amount of the plasticizer (B) added is preferably 20 to 200 parts with respect to 100 parts of the vinyl chloride resin. If the amount is less than 20 parts, the effect of imparting flexibility may not be obtained and molding processability may be deteriorated. If the amount exceeds 200 parts, the plasticizer is not easily absorbed into the resin composition, and the plastic is not easily plasticized. Since the agent oozes out, there is a risk that shape retention and molding processability may deteriorate.

The unsaturated carboxylic acid ester copolymer (C) is an organic compound for imparting elasticity and weather resistance to the vinyl chloride resin (A). The unsaturated carboxylic acid alkyl ester represented by the general formula (Chemical Formula 1) And a copolymer of one or more compounds selected from the group of compounds represented by the general formula (Chemical formula 2), the general formula (Chemical formula 3), and the general formula (Chemical formula 4).
Further, the unsaturated carboxylic acid ester copolymer (C) may be one having an ethylene unit and / or a vinyl acetate unit copolymerized in its structure.

  The content of the unsaturated carboxylic acid ester copolymer (C) is 1 to 200 parts with respect to 100 parts of the vinyl chloride resin. When the amount is less than 1 part, the effect of improving the compression set characteristics cannot be obtained, and when it exceeds 200 parts, the moldability is deteriorated.

  The unsaturated carboxylic acid ester copolymer (C) preferably contains 6% or more, more preferably 60% or more of the unsaturated carboxylic acid ester unit represented by the general formula (Formula 1). When the content of the unsaturated carboxylic acid alkyl ester unit is less than 6%, the plasticizer becomes difficult to be absorbed and the compatibility with the vinyl chloride resin is insufficient. Therefore, compression set characteristics, weather resistance, and mechanical strength The improvement effect may not be obtained.

  The composition of the unsaturated carboxylic acid ester copolymer (C) is generally based on 100 parts by mass of the total amount of the unsaturated carboxylic acid alkyl ester unit represented by the general formula (Chemical Formula 1), the ethylene unit and the vinyl acetate unit. What contains 0.01-10 mass parts of 1 or more types of compounds chosen from the group of the compound shown to Formula (Formula 2) General formula (Formula 3) and General formula (Formula 4) in total is good. If the total content of these compounds is less than 0.01 part, the vulcanization density is lowered, and the compression set reducing effect and oil resistance may be lowered. On the other hand, if the total content of these compounds exceeds 10 parts, the vulcanization density becomes too high and sufficient mechanical strength may not be obtained.

  The content of ethylene units and / or vinyl acetate units in the unsaturated carboxylic acid ester copolymer (C) is preferably in the range of 10% or less for ethylene units and 30% or less for vinyl acetate units. When the ethylene unit content exceeds 10%, the compatibility with the vinyl chloride resin is lowered, and the moldability, mechanical strength, and shape retention at high temperatures may be lowered. When the content of the vinyl acetate unit exceeds 30%, the melt viscosity is lowered and the moldability and weather resistance may be lowered.

  Examples of the unsaturated carboxylic acid alkyl ester represented by the general formula (Chemical Formula 1) include, for example, methyl acrylate, ethyl acrylate, n-butyl acrylate, n-propyl acrylate, isobutyl acrylate, n-pentyl acrylate, isoamyl acrylate, and n-hexyl. There are acrylate, 2-methylpentyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and the like, and one or more of these can be used.

  Examples of the compound represented by the general formula (Formula 2) include glycidyl acrylate and glycidyl methacrylate. Examples of the compound represented by the general formula (Formula 3) include vinyl glycidyl ether and allyl glycidyl ether. Examples of the compound represented by the general formula (Formula 4) include vinyl chloroacetate and 2-chloroethyl vinyl ether. These compounds represented by the general formula (Chemical Formula 2) to the general formula (Chemical Formula 4) may be used alone or as a mixture of a plurality of types.

The unsaturated carboxylic acid ester copolymer (C) may be a copolymer obtained by copolymerizing another monomer copolymerizable with the above-mentioned monomer within a range not impairing the object of the present invention. Examples of other copolymerizable monomers include unsaturated carboxylic acids in which R _{2 in} the general formula (Chemical Formula 1) such as n-decyl acrylate, n-dodecyl acrylate, n-octadecyl acrylate and the like is 9 or more carbon atoms. Alkyl ester, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2- (n-propoxy) ethyl acrylate, 2- (n-butoxy) ethyl acrylate, 3-methoxypropyl acrylate, 3-ethoxypropyl acrylate, 2- ( and (meth) acrylic acid alkoxyalkyl esters such as n-propoxy) propyl acrylate and 2- (n-butoxy) propyl acrylate.

  Further, cyanomethyl acrylate, 1-cyanoethyl acrylate, 2-cyanoethyl acrylate, 1-cyanopropyl acrylate, 2-cyanopropyl acrylate, 3-cyanopropyl acrylate, 4-cyanobutyl acrylate, 6-cyanohexyl acrylate, 2-ethyl- Cyano-containing acrylic acid esters such as 6-cyanohexyl acrylate and 8-cyanooctyl acrylate, 1,1-dihydroperfluoroethyl (meth) acrylate, 1,1-dihydroperfluoropropyl (meth) acrylate, 1,1,5- Trihydroperfluorohexyl (meth) acrylate, 1,1,2,2-tetrahydroperfluoropropyl (meth) acrylate, 1,1,7-trihydroperfluoroheptyl (meth) acrylate 1,1-dihydroperfluorooctyl (meth) acrylate, fluorine-containing acrylic acid ester such as 1,1-dihydroperfluorodecyl (meth) acrylate, 1-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, Hydroxyl group-containing acrylic esters such as hydroxyethyl (meth) acrylate, tertiary amino group-containing acrylic esters such as diethylaminoethyl (meth) acrylate and dibutylaminoethyl (meth) acrylate, methacrylates such as methyl methacrylate and octyl methacrylate, methyl Alkyl vinyl ketones such as vinyl ketone, vinyl and allyl ethers such as vinyl ethyl ether and allyl methyl ether, styrene, α-methyl styrene, chlorostyrene Vinyl aromatic compounds such as vinyl and toluene, vinyl nitriles such as acrylonitrile and methacrylonitrile, ethylene such as ethylene, propylene, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, vinyl propionate, and alkyl fumarate An unsaturated compound is mentioned.

  The unsaturated carboxylic acid ester copolymer (C) can be obtained by copolymerizing these monomers by a known method such as emulsion polymerization, suspension polymerization, solution polymerization or bulk polymerization.

  The thermoplastic elastomer composition of the present invention further has compression set characteristics and shape retention at high temperatures by blending the crosslinking agent (D) to crosslink the unsaturated carboxylic acid ester copolymer (C). It can also be improved.

What is necessary is just to select and employ | adopt suitably what is used for bridge | crosslinking of a normal rubber elastic body composition as a crosslinking agent (D), and there exists an imidazole compound as one of the crosslinking agents (D) used suitably.
Examples of the imidazole compound include 1-methylimidazole, 1,2-dimethylimidazole, 1-methyl-2-ethylimidazole, 1-benzyl-2-ethylimidazole, 1-benzyl-2-ethyl-5-methylimidazole, 1 -Benzyl-2-phenylimidazole, 1-benzyl-2-phenylimidazole trimellitic acid salt, 1-aminoethylimidazole, 1-aminoethyl-2-methylimidazole, 1-aminoethyl-2-ethylimidazole, 1- Cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-methylimidazole trimellitate , 1- Anoethyl-2-phenylimidazole trimellitate, 1-cyanoethyl-2-ethyl-4-methylimidazole trimellitate, 1-cyanoethyl-2-undecyl-imidazole trimellitate, 2,4-diamino-6- [2 ′ -Methylimidazolyl- (1) '] ethyl-s-triazine isocyanuric acid adduct, 1-cyanoethyl-2-phenyl-4,5-di- (cyanoethoxymethyl) imidazole, N- (2-methylimidazolyl- 1-ethyl) urea, N, N′-bis- (2-methylimidazolyl-1-ethyl) urea, 1- (cyanoethylaminoethyl) -2-methylimidazole, N, N ′-[2-methylimidazolyl- ( 1) -Ethyl] -aziboyldiamide, N, N ′-[2-methylimidazolyl- (1) -ethyl] -dodeca Dioiloylamide, N, N ′-[2-methylimidazolyl- (1) -ethyl] -eicosanedioyldiamide, 2,4-diamino-6- [2′-methylimidazolyl- (1) ′]-ethyl- s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1) ']-ethyl-s-triazine, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 1,3 -Dibenzyl-2-methylimidazolium chloride etc. are mentioned. Further, a crosslinking system containing an imidazole compound, particularly a system in which trimethylthiourea is added thereto is more preferably used.

  When imidazole is employ | adopted as a crosslinking agent (D), the compounding quantity has preferable 0.01-20 parts with respect to 100 parts of unsaturated carboxylic ester-type copolymers (C). If it is less than 0.01 part, crosslinking of the rubber elastic composition may not be sufficiently achieved, and the effect of improving compression set characteristics and shape retention at high temperature may not be obtained. While promoting the oxidative deterioration of the vinyl chloride resin composition in the elastomer composition, the vulcanization density of the rubber component may become too high, leading to a decrease in thermal stability and mechanical strength. In addition, the compounding quantity here is the number of parts as an active ingredient except a support body.

  Another example of the crosslinking agent (D) that is suitably used is an organic peroxide compound. When the thermoplastic peroxide composition of the present invention is melt-kneaded, the organic peroxide compound increases the fluidity of the composition by decomposing the unsaturated carboxylic acid ester copolymer (C), and the rubber component. To improve the dispersion. At the same time, radicals are generated and the radicals are chain-reacted to crosslink the unsaturated carboxylic acid ester copolymer (C). Furthermore, it has the effect of accelerating the crosslinking of the unsaturated carboxylic acid ester copolymer (C) with a crosslinking aid that is optionally used.

  Organic peroxide compounds include, for example, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl- 2,5-di- (tert-butylperoxy) hexyne-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3, 3,5 -Trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert -Butylperoxyisopropyl carbonate, diacetyl peroxide, lauroy Peroxide, tert- butyl cumyl peroxide, and the like. Of these, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-, from the viewpoint of odor, colorability and scorch safety Di- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexyne-3 are particularly preferred. In addition to pure products, those supported on calcium carbonate, diatomaceous earth, silica or the like can also be used.

  The compounding amount of the organic peroxide compound is determined in consideration of the quality of the thermoplastic elastomer composition to be obtained, but the preferred range is the same as the case of using the imidazole compound.

  When an organic oxide compound is employed as the crosslinking agent (D), a crosslinking aid can be added to promote the crosslinking, thereby enabling uniform and efficient crosslinking. . Examples of the crosslinking aid include polyfunctional methacrylate monomers such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate, divinylbenzene, vinyl Polyfunctional vinyl monomers such as butyrate or vinyl stearate, triallyl cyanurate, triallyl isocyanurate and the like can be blended.

  Of the crosslinking aids, trimethylolpropane trimethacrylate and ethylene glycol dimethacrylate are preferred. This compound is easy to handle, has good compatibility with the vinyl chloride resin composition and the unsaturated carboxylic acid ester copolymer (C), which are the main components in the composition, and has an organic solvent. Since it has an oxide solubilizing action and acts as a dispersion aid for organic peroxides, crosslinking by heat treatment is uniformly and effectively performed, and a thermoplastic elastomer composition having a balance between hardness and rubber elasticity can be obtained.

  Furthermore, as other examples of the crosslinking agent (D) that can be suitably used, tetramethylenepentamine, hexaethylenetetramine, hexamethylenediamine carbamate, N, N′-dicinnamylidene-1,6-hexanediamine, hexamethylenediamine, 4 , 4′-methylenedianiline, 4,4′-oxyphenyldiphenylamine, 4,4′-methylenebis (o-chloroaniline), 4,4′-diaminobenzanilide, 3,3′-dimethyl-4,4 ′ -Polyamines such as diaminodiphenylmethane, and thermally decomposable ammonium salts such as ammonium benzoate, ammonium citrate, and ammonium tartrate. These can also be used in combination with metal salts of dithiocarbamic acid, thiurams, sulfur, etc. it can.

  The crosslinking of the unsaturated carboxylic acid ester copolymer (C) is performed by melt-kneading these crosslinking agents (D) at 120 to 220 ° C. by a general method. If the temperature is less than 120 ° C., the rubber elastic body is not sufficiently crosslinked, and the compression set may not be improved. On the other hand, if the temperature exceeds 220 ° C., the target thermoplastic elastomer composition may undergo thermal decomposition, and the resulting thermoplastic elastomer composition may have poor thermal stability and mechanical strength.

  In the thermoplastic elastomer composition of the present invention, a filler may be used to give the product the required hardness, flexibility, physical properties and moldability.

  Specific examples of the filler include calcium carbonate, talc, silica, clay, aluminum hydroxide, magnesium hydroxide, antimony oxide, and spherical glass filler. Among these, calcium carbonate and / or talc are preferable in that the shapeability of the vinyl chloride resin composition during molding is greatly improved. The calcium carbonate may be either heavy calcium carbonate or light calcium carbonate.

  The amount of the filler is preferably 3 to 200 parts, more preferably 5 to 150 parts, per 100 parts of the vinyl chloride resin (A). If the amount is less than 3 parts, the moldability of the detailed shape of the molded product may be poor, and if it exceeds 200 parts, the surface of the molded product may not be smooth.

  Further, the thermoplastic elastomer composition of the present invention includes ethylene-vinyl acetate copolymer, acrylic resin, chlorinated polyethylene, polyurethane, acrylonitrile-butadiene copolymer, etc. within a range that does not extremely reduce the performance. Thermoplastic resins with excellent compatibility with vinyl chloride resins, flame retardants such as antimony trioxide and zinc borate, which are usually added to vinyl chloride resins, barium stearate, zinc stearate and tribasic lead sulfate Various additives such as heat stabilizers such as antioxidants, ultraviolet absorbers, lubricants, and colorants can be added as necessary.

  The method for mixing and kneading each component constituting the thermoplastic elastomer composition and the method for molding the obtained thermoplastic elastomer composition are not particularly limited, and general kneading methods and molding methods are used. Can be used.

  For example, each component is mixed in a mixer such as a high-speed mixer such as a Henschel mixer or a super mixer or a ribbon blender in the same manner as a normal vinyl chloride resin-based resin composition. What is necessary is just to blend uniformly for the time suitable for each mixer. For kneading, an open roll, a closed kneader (for example, a Banbury mixer, a pressure kneader, an intensive mixer) and a granulator attached to a strainer or the like after forming the kneaded product into a sheet with an open roll, Single-screw extruder, same-direction rotating twin-screw extruder (TEM manufactured by Toshiba Machine Co., Ltd., PCM manufactured by Ikegai Iron Works Co., Ltd.), double-direction rotating twin-screw extruder (TEC manufactured by Toshiba Machine Co., Ltd., PCM manufactured by Ikekai Iron Works Co., Ltd.), Kneader, Kneader Luder type high-speed agitating extruder (FCM manufactured by Kobe Steel), having a conical rotor having a plurality of grooves on the surface and a recess corresponding to the outer shape of the rotor, and having a plurality of grooves on the concave surface. Use a plasticizer (manufactured by WERNER & PFLEIDER) or a plasticizer (manufactured by Ichiki Seisakusho Co., Ltd.), which is a kneading extruder with a structure that combines a barrel. It can be carried out.

  Among these kneaders, a closed kneader in which the kneading time can be freely selected, a kneader excellent in kneading effect, a bi-directionally rotating twin-screw extruder, a plasticizer, and a plasticizer are preferably used. For example, kneading is performed by adjusting the jacket temperature, cylinder temperature, screw temperature, rotation speed, and kneading time so that the temperature of the blend itself is usually 140 to 220 ° C.

  When molding the thermoplastic elastomer composition of the present invention, it is possible to apply a molding machine used for molding ordinary resin materials, such as extrusion molding, injection molding, calender molding or compression molding. The desired molded product can be obtained without using a time-consuming vulcanization step. Furthermore, the molded defective parts such as defective moldings and sprue runners that occur when the composition of the present invention is molded into a desired shape are different from the case of vulcanized rubber, and are subjected to treatment such as pulverization as necessary. The obtained thermoplastic elastomer composition has the advantage that it can be mixed with the thermoplastic elastomer composition before being pulverized and re-molded. In mixing with a mixer, some or all of these raw materials may be pre-blended in advance with a Henschel mixer and a ribbon blender and then applied to the mixer, or may be applied all at once without pre-blending. . Alternatively, a part of the raw material may be pre-pelletized and then applied to a mixer.

  There are no particular limitations on the extrusion molding apparatus, and commonly used single and biaxial screws can be used, which can be appropriately selected depending on the material used and the shape and dimensions of the mold. It can be co-extruded in multiple layers.

  The injection molding machine is not particularly limited, and an injection molding machine usually used for a thermoplastic elastomer composition is used.

  The extruded product of the present invention is excellent in weather resistance, compression set characteristics and shape retention at high temperatures, so it is a member for automobile exterior such as weather strip, glass run channel, window molding, belt molding, various sealing materials and various gaskets. Can be used widely for industrial packing materials, including cables, curling cords, microphone cords and other wire covering members, and waterproofing civil engineering sheets, water-stopping civil engineering sheets, and window frame glazing and other architectural members. it can. Also, injection molded products are widely used as industrial packing materials including automotive exterior members such as door mirror packing, shift lever boots, side brake covers, headrest and armrests, various sealing materials and various gaskets. be able to.

Example 1
Hereinafter, the present invention will be described more specifically with reference to examples.
This example is a thermoplastic elastomer composition having 100 parts of a vinyl chloride resin, 100 parts of a plasticizer, 10 parts of an unsaturated carboxylic ester copolymer, 1.4 parts of a crosslinking agent and other additives. It is.
Here, the vinyl chloride resin is a commercially available product having a polymerization degree of 2500, the plasticizer is di-2-ethylhexyl phthalate, which is a commercially available product, and the unsaturated carboxylic acid ester copolymer is composed of 4% ethylene, acetic acid. 100 parts of ethylene-vinyl acetate-unsaturated carboxylic acid alkyl ester copolymer having a composition of 12% vinyl and 84% n-butyl acrylate is copolymerized with 3.8 parts glycidyl methacrylate, This is a support of 1-cyanoethyl-2-methylimidazole on calcium carbonate (1-cyanoethyl-2-methylimidazole: 25%, calcium carbonate: 75%). As additives, Asahi Denka Co., Ltd. 2 parts O-180A (trade name) as heat stabilizer 1, Asahi Denka Co., Ltd. Adekastab AC183 (trade name) 1 part, and filler Nitto Kasei Co., Ltd. NS400 (trade name) 50 parts.
These are put into a 20-liter pressure kneader at a time, kneaded for 10 minutes at a screw speed of 100 rpm until the temperature reaches 170 ° C., and then cooled, and the resulting kneaded product is formed into a sheet with a 160 ° C. roll. After molding, it was pelletized with a pelletizer to obtain 15 kg of a thermoplastic elastomer composition. Next, this thermoplastic elastomer composition was subjected to extrusion evaluation with a 40 mm extruder (Placo Corporation). In addition, the die | dye which can obtain the molded article of the shape shown in FIG. 1 was used as a die | dye of an extruder. Moreover, this molded product is a rod-shaped body that continues in the longitudinal direction of the drawing.

  The obtained molded products were evaluated by the test methods shown below, and the results are shown in Table 1. Unless otherwise specified, the other examples and comparative examples in the present invention are the same as the present examples.

(Weatherability)
No. 3 dumbbell defined in JIS K6251 was exposed to carbon arc type sunshine weatherometer (manufactured by Suga Test Instruments Co., Ltd.) for 1000 hours with a black panel temperature of 63 ° C and a cycle of fine weather 108 minutes / rain 12 minutes. Change and tensile strength were evaluated. The vinyl chloride resin composition is used as a reference, the gloss is equal to or higher than that, and the change in residual tensile strength is within 10%, the gloss is lowered and the appearance is slightly inferior, or the change in residual tensile strength is 10%. A 30% sample was indicated by Δ, and an appearance or remarkably inferior tensile strength change was marked by ×.

(Shape retention at high temperatures)
The height from the bottom surface 1 of the shaped product of FIG. 1 obtained by extrusion molding to the upper end 21 of the lip 2 was measured (original height). Furthermore, as shown in FIG. 2, the spacer 4 was inserted between the molds 3 and 3 of the molded product, and 25% of the height from the bottom of the molded product was compressed and held at 70 ° C. for 22 hours. Thereafter, the compressed molded product was taken out to room temperature and left for 30 minutes. The height from the bottom surface 1 of the left molded product to the lip upper end 21 was measured (height after compression). The shape retention (%) at high temperature was calculated using the general formula (Equation 1). When the calculated value was less than 60%, it was marked as ◯, 60-80% as Δ, and 80% or more as x.

(Compression set)
Based on JIS K6262, the compression set was evaluated under test conditions of 70 ° C. × 22 hours.

(Tensile strength)
Tensile tests at a speed of 500 mm / min of No. 3 dumbbell defined in JIS K6251 were performed three times each, and the median value was taken as the tensile strength.

(Molding processability)
Using a 40 m / m single screw extruder, extrusion was performed at a die temperature of 170 ° C., and the extrusion moldability was evaluated. ◎ if the molded product is smooth and good in shape, ○ if the surface of the molded product is smooth but rough, △ if the surface of the molded product is wavy and non-smooth, and wavy is seen on the surface of the molded product Furthermore, the case where a molded product having a dimension as the shape of the die could not be obtained was evaluated as x.

(Example 2 to Example 4)
The unsaturated carboxylic acid ester copolymer and the crosslinking agent in the thermoplastic elastomer composition of Example 1 are changed to the blending amounts shown in Table 1. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

(Comparative Example 1 and Comparative Example 2)
The unsaturated carboxylic acid ester copolymer and the crosslinking agent in the thermoplastic elastomer composition of Example 1 are changed to the blending amounts shown in Table 1. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

(Comparative Example 3, Comparative Example 4)
The unsaturated carboxylic acid ester copolymer in the thermoplastic elastomer composition of Example 1 was changed to a partially crosslinked nitrile rubber (partially crosslinked acrylonitrile-butadiene copolymer, P83 manufactured by Goodyear Co., Ltd.) and shown in Table 1, respectively. A thermoplastic elastomer composition is obtained at a blending amount. In these comparative examples, a crosslinking agent was not added again. The same evaluation as in Example 1 was performed, and the results are shown in Table 1.

(Examples 5 to 8)
The vinyl chloride resins in the thermoplastic elastomer composition of Example 1 were changed to those having a polymerization degree shown in Table 2, respectively. The same evaluation as in Example 1 was performed, and the results are shown in Table 2.

(Examples 9 to 14)
The unsaturated carboxylic acid ester copolymer in the thermoplastic elastomer composition of Example 1 is changed to those shown in Table 3, respectively. The same evaluation as in Example 1 was performed and the results are shown in Table 3. In Table 3, copolymer 2 to copolymer 7 have the compositions shown below.
Copolymer 2: 3.8 parts of glycidyl methacrylate was added to 100 parts of ethylene-vinyl acetate-unsaturated carboxylic acid alkyl ester copolymer having a composition of 30% ethylene, 67% vinyl acetate and 3% n-butyl acrylate. Polymerized.
Copolymer 3: 3.8 parts of glycidyl methacrylate was added to 100 parts of ethylene-vinyl acetate-unsaturated carboxylic acid alkyl ester copolymer having a composition of 10% ethylene, 30% vinyl acetate and 60% n-butyl acrylate. Polymerized.
Copolymer 4: Ethylene-vinyl acetate-unsaturated carboxylic acid alkyl ester copolymer having a composition of 4% ethylene, 12% vinyl acetate, 49% ethyl acrylate, and 35% n-butyl acrylate was added to 100 parts of glycidyl methacrylate 3 .8 parts copolymerized.
Copolymer 5: A copolymer obtained by copolymerizing 3.8 parts of glycidyl methacrylate with 100 parts of unsaturated carboxylic acid alkyl ester polymer of 100% n-butyl acrylate.
Copolymer 6: An ethylene-vinyl acetate-unsaturated carboxylic acid alkyl ester copolymer having a composition of 6% ethylene, 10% vinyl acetate, and 84% n-butyl acrylate.
Copolymer 7: 16 parts of glycidyl methacrylate was copolymerized with 100 parts of ethylene-vinyl acetate-unsaturated carboxylic acid alkyl ester copolymer having a composition of 4% ethylene, 12% vinyl acetate and 84% n-butyl acrylate. Things.

(Example 15 to Example 17)
The crosslinking agents in the thermoplastic elastomer composition of Example 1 are changed to those shown in Table 4, respectively. In Example 16, a crosslinking aid was further added. The same evaluation as in Example 1 was performed, and the results are shown in Table 4. In Table 4, the crosslinking agent 1, the crosslinking agent 2 and the crosslinking aid are as shown below.
Crosslinking agent 1: 1,2-dimethylimidazole Crosslinking agent 2: 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane Crosslinking aid: trimethylolpropane trimethacrylate

It is the perspective view which showed typically the molded article for evaluating the shape retention property at the time of the high temperature of the thermoplastic elastomer composition of this invention. It is the figure which showed typically the measuring method of the high temperature retention evaluation of the thermoplastic elastomer composition of this invention.

Explanation of symbols

1 Bottom 2 Lip 21 Upper end of Lip 3 Mold 4 Spacer

Claims (7)

  Heat obtained by kneading 100 parts by mass of vinyl chloride resin (A), 20 to 200 parts by mass of plasticizer (B), and 1 to 200 parts by mass of unsaturated carboxylic ester copolymer (C). Plastic elastomer composition. The unsaturated carboxylic acid ester copolymer (C) comprises the unsaturated carboxylic acid alkyl ester represented by the general formula (Chemical Formula 1), the general formula (Chemical Formula 2), the general formula (Chemical Formula 3), and the general formula (Chemical Formula 4). The thermoplastic elastomer composition according to claim 1, wherein the thermoplastic elastomer composition is a copolymer with one or more kinds of compounds selected from the group of compounds shown in (1).

(Wherein R ₁ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₂ is an alkyl group having 1 to 8 carbon atoms)

(Wherein R ₃ is a hydrogen atom or a methyl group)

(Wherein R ₄ is a vinyl group, an allyl group, or a methallyl group)

(Wherein R ₅ is a CH ₂ (Cl) —CH ₂ — group or a CH ₂ (Cl) —CO— group). The thermoplastic elastomer composition according to claim 2, wherein the unsaturated carboxylic acid ester copolymer (C) is obtained by further copolymerizing ethylene units and / or vinyl acetate units.   The unsaturated carboxylic acid ester copolymer (C) contains 6% or more of the unsaturated carboxylic acid alkyl ester unit represented by the general formula (Chemical Formula 1) and the unsaturated carboxylic acid represented by the general formula (Chemical Formula 1). Selected from the group of compounds represented by the general formula (Chemical Formula 2), the general formula (Chemical Formula 3) and the general formula (Chemical Formula 4) with respect to 100 parts by mass of the total amount of the acid alkyl ester unit, the ethylene unit and the vinyl acetate unit. The thermoplastic elastomer composition according to claim 3, wherein the thermoplastic elastomer composition contains one or more kinds of compounds in a total amount of 0.01 to 10 parts by mass.   The unsaturated carboxylic acid ester copolymer (C) has an unsaturated carboxylic acid alkyl ester unit represented by the general formula (Chemical Formula 1) of 60% or more, an ethylene unit of 10% or less, and a vinyl acetate unit of 30% or less. In addition to the total content of 100 parts by mass of the unsaturated carboxylic acid alkyl ester unit represented by the general formula (Chemical Formula 1), the ethylene unit and the vinyl acetate unit, the general formula (Chemical Formula 2) ) And one or more kinds of compounds selected from the group of compounds represented by the general formula (Chemical Formula 4) in a total amount of 0.01 to 10 parts by mass, The thermoplastic elastomer according to claim 3 Composition.   The thermoplastic elastomer composition according to any one of claims 1 to 5, wherein the vinyl chloride resin (A) has an average degree of polymerization of 800 to 4000. The cross-linking agent (D) is further contained in an amount of 0.01 to 20 parts by mass with respect to 100 parts by mass of the unsaturated carboxylic acid ester copolymer (C). The thermoplastic elastomer composition described in the item.

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