JP2015209504A - Transparent vinyl chloride resin composition and molded product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent vinyl chloride resin composition that offers an excellent balance of impact resistance and transparency, and a molded product comprising the vinyl chloride resin composition.SOLUTION: A vinyl chloride resin composition comprises vinyl chloride resin (A) and acrylic block copolymer (B), where the content of the acrylic block copolymer (B) is 3-15 pts. mass relative to the vinyl chloride resin (A)100 pts. wt.

Description

  The present invention relates to a vinyl chloride resin composition and a molded article comprising the vinyl chloride resin composition.

  Vinyl chloride-based resin compositions are widely used in various molded products by taking advantage of their characteristics, and various characteristics are required according to each application. Such required characteristics include, for example, high volume resistivity, good plasticizer absorbability, fisheye reduction, etc. in soft application fields such as electric wire coating, wrap film, sheet, etc., pipes, joints, windows In hard application fields such as frames, industrial transparent plates, films, etc., there are molding processability and thermal stability when processed into molded products, mechanical properties such as tensile strength and impact resistance after molding, and transparency. It is required to be good.

  Various attempts have been made to improve these required characteristics. For example, in order to improve mechanical properties such as impact resistance in the field of hard applications, methyl methacrylate-butadiene-styrene copolymer is added to vinyl chloride resin. (Hereinafter abbreviated as MBS resin) or a method of adding a core-shell type impact modifier obtained by graft polymerization of a vinyl chloride monomer to an acrylic polymer crosslinked with a polyfunctional monomer (Patent Document 1) has been studied. Yes. However, in this method, since the fluidity of the impact modifier having a crosslinked structure is low, the melt flow characteristics at the time of molding processing are poor, and there may be problems in terms of manufacturing conditions such as an increase in the motor load of the extruder.

  In addition, in order to improve the melt flow characteristics at the time of molding, a method of copolymerizing a copolymer of butyl acrylate and methyl methacrylate not containing a crosslinked structure and a vinyl chloride monomer (Patent Document 2) is also being studied. . However, although the melt flowability of the resulting vinyl chloride copolymer is improved by this method, the impact resistance improving effect of the copolymer of butyl acrylate and methyl methacrylate is not sufficient, and crosslinking is not possible. Since the structure is not included, the dispersibility at the time of molding becomes unstable, and problems still remain in terms of transparency.

  Furthermore, as a method for obtaining a resin composition having an excellent balance between mechanical properties such as impact resistance and molding processability, a method of adding a block copolymer to a vinyl chloride resin (Patent Document 3) has also been studied. However, in this method, a block copolymer comprising a polymer block mainly composed of a structural unit derived from an aromatic vinyl compound and a polymer block mainly composed of a structural unit derived from a conjugated diene is added as an impact modifier. Therefore, only a resin composition that leaves problems in transparency and weather resistance has been obtained.

JP 2001-89622 A JP 2006-83332 A Japanese Patent Laid-Open No. 6-87998 Japanese Patent Publication No. 7-25859 JP-A-11-335432 JP-A-6-93060

Macromolecular Chemical Physics 201, 1108-1114 (2000)

  An object of this invention is to provide the transparent vinyl chloride-type resin composition excellent in the balance of impact resistance and transparency, and the molded article which consists of this resin composition.

According to the present invention, the above object is
(1) An acrylic block copolymer (B) having a vinyl chloride resin (A) and a polymer block (b1) comprising an acrylate unit and a polymer block (b2) comprising a methacrylic ester unit. A transparent vinyl chloride resin composition containing 3 to 15 parts by mass of an acrylic block copolymer (B) with respect to 100 parts by mass of a vinyl chloride resin (A). ;
(2) The transparent vinyl chloride resin according to (1), wherein the polymer block (b1) has a glass transition temperature of 25 ° C. or lower and the polymer block (b2) has a glass transition temperature of 60 ° C. or higher. Composition;
(3) The transparent block according to (1) or (2), wherein the acrylic block copolymer (B) is a triblock copolymer in which the polymer block (b2) is bonded to both ends of the polymer block (b1). Vinyl chloride resin composition;
(4) The transparent vinyl chloride resin according to any one of (1) to (3), wherein the content of the polymer block (b1) constituting the acrylic block copolymer (B) is 80 to 40% by mass. Composition;
(5) The transparent vinyl chloride resin composition according to any one of (1) to (4), wherein the molecular weight distribution of the acrylic block copolymer (B) is in the range of 1.0 to 1.4;
(6) The transparent vinyl chloride resin composition according to any one of (1) to (5), wherein the weight average molecular weight of the acrylic block copolymer (B) is in the range of 10,000 to 200,000;
(7) The polymer block (b2) constituting the acrylic block copolymer (B) has a weight average molecular weight in the range of 2,000 to 100,000, according to any one of (1) to (6). Transparent vinyl chloride resin composition;
(8) A molded article comprising the transparent vinyl chloride resin composition according to any one of (1) to (7);
Is achieved by providing

  According to the present invention, it is possible to provide a transparent vinyl chloride resin composition excellent in the balance between impact resistance and transparency, and a molded article comprising the resin composition.

Hereinafter, the invention will be described in detail.
<Vinyl chloride resin (A)>
The vinyl chloride resin (A), which is a constituent of the transparent vinyl chloride resin composition of the present invention, is a resin mainly composed of vinyl chloride units, and is obtained by polymerizing a monomer containing vinyl chloride. The vinyl chloride resin (A) is a resin containing vinyl chloride units, preferably 50% by mass or more, more preferably 70% by mass or more. Examples of the vinyl chloride resin (A) include a vinyl chloride homopolymer (polyvinyl chloride) and a vinyl chloride copolymer.

Examples of monomers other than vinyl chloride constituting the vinyl chloride copolymer include, for example, α-olefins such as ethylene and propylene; vinyl acetate, vinyl ether, acrylic acid ester, methacrylic acid ester, acrylamide, methacrylamide, Examples include acrylonitrile, methacrylonitrile, maleimides, vinylidene chloride, and styrene. These can be used alone or in combination of two or more.
The degree of polymerization of the vinyl chloride resin (A) may be appropriately set according to its use, etc., but is usually in the range of 100 to 10,000, and from the viewpoint of moldability, the range of 400 to 5000 is. preferable.

<Acrylic block copolymer (B)>
The acrylic block copolymer (B), which is a constituent of the transparent vinyl chloride resin composition of the present invention, comprises a polymer block (b1) composed of acrylate units and a polymer block (b2) composed of methacrylate units. ).

  The polymer block (b1) is mainly composed of acrylate units. Examples of the acrylic acid ester for forming the polymer block (b1) include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, and acrylic. Amyl acid, Isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, dodecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, phenoxyethyl acrylate, acrylic acid Examples include 2-hydroxyethyl, 2-methoxyethyl acrylate, glycidyl acrylate, and allyl acrylate. Among them, from the viewpoint of improving impact strength, fluidity, etc. of the transparent vinyl chloride resin composition of the present invention, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, tert-butyl acrylate, acrylic Acrylic acid alkyl esters such as 2-ethylhexyl acid and dodecyl acrylate are preferable, and n-butyl acrylate and 2-ethylhexyl acrylate are more preferable.

  The content of the acrylate unit in the polymer block (b1) is preferably 60% by mass or more, and more preferably 80% by mass or more. These acrylic acid esters may be used alone or in combination of two or more.

  The glass transition temperature (Tg) of the polymer block (b1) is preferably 25 ° C. or lower, more preferably 0 ° C. or lower, and further preferably −15 ° C. or lower. When the acrylic block copolymer (B) in which the Tg of the polymer block (b1) is 25 ° C. or less is used, the transparent vinyl chloride resin composition of the present invention and a molded product comprising the same are obtained which are more excellent in impact resistance. It is done. The glass transition temperature is an extrapolation start temperature of a curve obtained by DSC measurement.

  Further, within the range where the effects of the present invention are exerted, the polymer block (b1) is a small amount (preferably 10 mol% or less, more preferably 5 mol) with a monomer other than the acrylate unit as a copolymerization component. % Or less). Examples of the other monomer include a methacrylic acid ester mainly constituting a polymerization block (b2) described later, methacrylic acid, acrylic acid, an aromatic vinyl compound, acrylonitrile, methacrylonitrile, and an olefin.

  The polymer block (b2) is mainly composed of methacrylic acid ester units. Examples of the methacrylic acid ester for forming the polymer block (b2) include, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacrylic acid. sec-butyl, tert-butyl methacrylate, amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, dodecyl methacrylate, isobornyl methacrylate, phenyl methacrylate, Benzyl methacrylate, phenoxyethyl methacrylate, 2-hydroxyethyl methacrylate, 2-methoxyethyl methacrylate, glycidyl methacrylate, allyl methacrylate Etc., and the like. Among them, from the viewpoint of improving the impact strength of the transparent vinyl chloride resin composition of the present invention, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate. Further, alkyl methacrylates such as cyclohexyl methacrylate and isobornyl methacrylate are preferable, and methyl methacrylate is more preferable.

The content of the methacrylic acid ester unit in the polymer block (b2) is preferably 60% by mass or more, and more preferably 80% by mass or more. These methacrylic acid esters may be used alone or in combination of two or more.
The glass transition temperature (Tg) of the polymer block (b2) is preferably 60 ° C. or higher, and more preferably 100 ° C. or higher. When the acrylic block copolymer (B) having a Tg of the polymer block (b2) of 60 ° C. or higher is used, the transparent vinyl chloride resin composition of the present invention is more excellent in heat resistance (maintaining mechanical properties at high temperature). And a molded product comprising the same.

  Further, within the range where the effects of the present invention are exerted, the polymer block (b2) is a small amount (preferably 10 mol% or less, more preferably 5), with other monomers other than the methacrylic acid ester unit as a copolymerization component. (Mol% or less) may be used. Examples of the other monomer include acrylic acid ester, methacrylic acid, acrylic acid, aromatic vinyl compound, acrylonitrile, methacrylonitrile, olefin and the like mainly constituting the polymer block (b1).

The acrylic block copolymer (B) is composed of a polymer block (b1) consisting of an acrylate unit and a polymer block (b2) consisting of a methacrylic ester unit, and the bonding form of these polymer blocks is particularly For example, any of linear, branched, radial, and the like may be used. Among them, the bonding form of the polymer block (b1) and the polymer block (b2) is preferably linear, and the polymer block (b1) is (b1) and the polymer block (b2) is ( When represented by b2), for example, it is represented by a diblock copolymer represented by (b2)-(b1), (b2)-(b1)-(b2) or (b1)-(b2)-(b1) And a triblock copolymer represented by (b2)-(b1)-(b2)-(b1). Among these, from the viewpoint of improving impact strength, heat resistance, etc. of the transparent vinyl chloride resin composition of the present invention, the polymer block (b2) is bonded to both ends of the polymer block (b1) (b2)-(b1). -(B2) A triblock copolymer is preferable.
The acrylic block copolymer (B) may be a gradient block copolymer in which the polymer block (b1) has a gradient structure. The gradient structure here refers to, for example, the following polymer block (b2) in the polymer block (b1) in the triblock copolymer having the structure (b2)-(b1)-(b2). This refers to a structure in which the copolymerization ratio of methacrylic acid ester units to be continuously increased to form a polymer block (b2).

  In the range where the effects of the present invention are exhibited, the acrylic block copolymer (B) is a polymer block formed from monomers other than the acrylic ester and methacrylic ester separately from the above-described polymer block ( s). The bonding form of the polymer block (s), the polymer block (b1) composed of the acrylate unit, and the polymer block (b2) composed of the methacrylic ester unit is not particularly limited. For example, (b2)- {(B1)-(b2)} n- (s) structure, (s)-(b2)-{(b1)-(b2)} n- (s) structure (n represents a natural number), etc. Is mentioned. Examples of the monomer constituting the polymer block (s) include olefins such as ethylene, propylene, 1-butene, isobutylene and 1-octene; conjugated dienes such as butadiene, isoprene and myrcene; styrene, α-methylstyrene, Aromatic vinyl compounds such as p-methylstyrene and m-methylstyrene; vinyl acetate, vinylpyridine, acrylonitrile, methacrylonitrile, vinyl ketone monomers, vinyl chloride, vinylidene chloride, vinylidene fluoride, acrylamide, methacrylamide, ε- Examples include caprolactone and valerolactone.

The weight average molecular weight in terms of polystyrene determined by gel permeation chromatography (GPC) measurement of the acrylic block copolymer (B) is the balance between the impact resistance and transparency of the transparent vinyl chloride resin composition of the present invention. From the viewpoint, the range of 10,000 to 200,000 is preferable, and the range of 15,000 to 150,000 is more preferable. When the weight average molecular weight of the acrylic block copolymer (B) is smaller than the above range, the melt viscosity is lowered, the melt kneading property with the vinyl chloride resin (A) is deteriorated, and the resulting molded product The mechanical strength tends to be inferior. In addition, the weight average molecular weight of the polymer block (b1) composed of acrylate units in the acrylic block copolymer (B) is preferably in the range of 2,000 to 100,000, and 5,000 to 80,000. The range of is more preferable. The weight average molecular weight of the polymer block (b2) comprising methacrylic acid ester units is preferably in the range of 2,000 to 100,000, and more preferably in the range of 5,000 to 80,000.
The content of the polymer block (b1) in the acrylic block copolymer (B) is 80 to 40 masses from the viewpoint of the balance between impact resistance and transparency of the transparent vinyl chloride resin composition of the present invention. %, More preferably 75 to 45% by mass, and still more preferably 70 to 50% by mass. When the content of the polymer block (b1) is within the above range, in the transparent vinyl chloride resin composition of the present invention, the dispersibility of the acrylic block copolymer (B) is improved and the impact resistance is improved. Excellent transparency.
The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the acrylic block copolymer (B) is preferably 1.0 to 1.4, more preferably 1.0 to 1.3. When the molecular weight distribution is in the above range, molding processability when the transparent vinyl chloride resin composition of the present invention is melt-molded can be stabilized.

The acrylic block copolymer (B) may have a functional group such as a hydroxyl group, a carboxyl group, an acid anhydride, or an amino group in the molecular chain or at the molecular chain end, if necessary.
As a manufacturing method of an acrylic block copolymer (B), the method of living polymerizing the monomer which comprises each block is preferable. Examples of the living polymerization method include a method in which an organic alkali metal compound is used as a polymerization initiator and living anion polymerization is performed in the presence of a mineral salt such as a salt of an alkali metal or an alkaline earth metal (see Patent Document 4), organic A method of living anion polymerization using an alkali metal compound as a polymerization initiator in the presence of an organoaluminum compound (see Patent Document 5), a method of living polymerization using an organic rare earth metal complex as a polymerization initiator (see Patent Document 6), α- Examples thereof include a method of living radical polymerization using a halogenated ester compound as an initiator in the presence of a copper compound (see Non-Patent Document 1). Moreover, the monomer which comprises each polymer block is polymerized using a polyvalent radical polymerization initiator and a polyvalent radical chain transfer agent, and the acrylic block copolymer (B) used by this invention is contained. The method of manufacturing as a mixture is also mentioned. Among these, the acrylic block copolymer (B) is obtained with a narrow molecular weight distribution and high purity, that is, an oligomer that causes a decrease in impact resistance of the transparent vinyl chloride resin composition of the present invention, From the viewpoint of suppressing by-product formation of a high molecular weight compound that causes a decrease in the property, a method of living anion polymerization using an organic alkali metal compound as a polymerization initiator in the presence of an organic aluminum compound is preferable.

  Examples of the organoaluminum compound include isobutyl bis (2,6-di-t-butyl-4-methylphenoxy) aluminum, isobutyl bis (2,6-di-t-butylphenoxy) aluminum, and isobutyl bis [2,2 ′. -Methylenebis (4-methyl-6-t-butylphenoxy)] aluminum, n-octylbis (2,6-di-t-butyl-4-methylphenoxy) aluminum, n-octylbis (2,6-di-t- Butylphenoxy) aluminum, n-octylbis [2,2′-methylenebis (4-methyl-6-tert-butylphenoxy)] aluminum, tris (2,6-di-tert-butyl-4-methylphenoxy) aluminum, tris Examples include (2,6-diphenylphenoxy) aluminum. Among them, isobutylbis (2,6-di-t-butyl-4-methylphenoxy) aluminum, isobutylbis (2,4-di-t-butylphenoxy) aluminum, n-octylbis (2,6-di-t-) Butyl-4-methylphenoxy) aluminum or n-octylbis (2,4-di-t-butylphenoxy) aluminum is particularly preferred from the viewpoint of polymerization activity, block efficiency and the like.

<Transparent vinyl chloride resin composition>
The transparent vinyl chloride resin composition of the present invention contains the vinyl chloride resin (A) and the acrylic block copolymer (B). The content of the acrylic block copolymer (B) in the transparent vinyl chloride resin composition of the present invention is based on 100 parts by mass of the vinyl chloride resin (A) from the viewpoint of both transparency and impact resistance. 3 to 15 parts by mass. When a rubber-based modifier is added to improve impact resistance, in the case of a transparent material, transparency (light transmittance, haze) and impact resistance (Charpy impact strength) can be achieved by adding a modifier. There is a trade-off relationship. Therefore, when the blending amount of the acrylic block copolymer (B) is less than the above range, the transparency is excellent but the impact resistance is insufficient, and the blending amount of the acrylic block copolymer (B) is small. When the amount is more than the above range, the impact resistance is excellent but the transparency is lowered. The present invention is characterized in that a transparent vinyl chloride resin composition having an excellent balance between transparency and impact resistance can be obtained by using the acrylic block copolymer (B) in the above blending amount. From the above viewpoint, the content of the acrylic block copolymer (B) is more preferably 5 to 12 parts by mass with respect to 100 parts by mass of the vinyl chloride resin (A), and 5 to 10 parts by mass. More preferably it is.

In the transparent vinyl chloride resin composition of the present invention, the light transmittance is preferably 86% or more, and more preferably 87% or more. The haze is preferably 5% or less, more preferably 3% or less. When the light transmittance and haze are within the above ranges, sufficient transparency can be obtained. In the transparent vinyl chloride resin composition of the present invention, the Charpy impact strength is preferably 5 kJ / m ² or more, and more preferably 7 kJ / m ² . When the Charpy impact strength is within the above range, sufficient impact resistance can be obtained. In addition, light transmittance, haze, and Charpy impact strength can be measured according to the method described in the Examples using a test piece (molded product) obtained by molding the transparent vinyl chloride resin composition of the present invention.

  In addition to the vinyl chloride resin (A) and the acrylic block copolymer (B), the thermoplastic resin composition of the present invention can be used as necessary as long as the effects of the present invention are not impaired. And may contain other polymers and additives. Examples of other polymers that can be blended include acrylic rubber, polybutene rubber, polyisobutylene rubber, and synthetic rubbers such as EPR and EPDM. Examples of additives include mineral oil softeners such as paraffinic oil and naphthenic oil for improving fluidity during molding; carbon dioxide for the purpose of improving heat resistance, weather resistance, etc. Inorganic fillers such as calcium, talc, carbon black, titanium oxide, silica, clay, barium sulfate, magnesium carbonate; inorganic fibers or organic fibers such as glass fibers and carbon fibers for reinforcement; General in vinyl chloride resin compositions Plasticizers used in general; Lubricants; Thermal stabilizers; Antioxidants; Light stabilizers; Adhesives; Tackifiers; Antistatic agents; Among these additives, in order to further improve heat resistance and weather resistance, it is practically preferable to add a heat stabilizer, an antioxidant and the like. As the heat stabilizer, for example, lead stearate, barium stearate, tribasic lead sulfate or the like can be used.

  The method for producing the transparent vinyl chloride resin composition of the present invention is not particularly limited, and from the viewpoint of improving the dispersibility of each component constituting the resin composition, for example, a melt kneading method is preferable. For example, a method in which the vinyl chloride resin (A) and the acrylic block copolymer (B) are melt-kneaded together with the above-mentioned other polymers or additives as necessary; the vinyl chloride resin (A) Examples thereof include a method in which the acrylic block copolymer (B) is mixed and melt-kneaded after mixing with the other polymer or additive. The melt-kneading operation can be performed using a known mixing or kneading apparatus such as a kneader ruder, an extruder, a mixing roll, or a Banbury mixer. In particular, it is preferable to use a twin screw extruder from the viewpoint of improving the kneadability and compatibility of the vinyl chloride resin (A) and the acrylic block copolymer (B). The temperature at the time of melt kneading can be suitably adjusted according to the melting temperature of the vinyl chloride resin (A), acrylic block copolymer (B), etc. to be used, and is usually in the range of 110 ° C to 300 ° C. Do at temperature. In this way, the transparent vinyl chloride resin composition of the present invention can be obtained in any form such as pellets or powder. The resin composition in the form of pellets, powders and the like is suitable for use as a molding material.

<Molded product>
The transparent vinyl chloride resin composition of the present invention is excellent in melt fluidity and can be molded using a molding method and a molding processing apparatus generally used for thermoplastic resins. For example, it can be molded by injection molding, extrusion molding, compression molding, blow molding, calendar molding, vacuum molding, and the like, and includes a mold, a pipe, a plate, a sheet, a film, a fibrous material, and a layer comprising the resin composition. A molded article having an arbitrary shape such as a body can be obtained.

The molded article comprising the transparent vinyl chloride resin composition of the present invention is excellent in balance of mechanical properties such as transparency and impact resistance, and is used not only for pipes, plates, films, sheets and containers, but also for indoor and outdoor use. It can be applied as a structural member, civil engineering and building material.
Further, the obtained molded product can be subjected to surface treatment such as printing, painting, plating, vapor deposition, and sputtering according to the purpose.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention concretely, this invention is not limited to these Examples. Various physical properties in Examples and Comparative Examples were measured or evaluated by the following methods.

(1) Measurement of number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) Number average molecular weight (Mn) of each acrylic block copolymer obtained in Synthesis Examples 2 to 4, The weight average molecular weight (Mw) was determined as a standard polystyrene equivalent molecular weight by gel permeation chromatography (hereinafter referred to as GPC), and the molecular weight distribution (Mw / Mn) was calculated therefrom. Moreover, it calculated | required similarly about the weight average molecular weight of the polymer block (b2) of each acrylic block copolymer.
・ Apparatus: GPC equipment “HLC-8020” manufactured by Tosoh Corporation
Column: “TSK1 GMHXL”, “G4000HXL” and “G5000HXL” manufactured by Tosoh Corporation are connected in series. Eluent: Tetrahydrofuran Eluent flow rate: 1.0 mL / min Column temperature: 40 ° C.
・ Detection method: Differential refractive index (RI)

(2) Measurement of glass transition temperature of polymer block constituting each acrylic block copolymer In the curve obtained by DSC measurement, the extrapolation start temperature (Tgi) was defined as the glass transition temperature (Tg).
・ Device: DSC-822 manufactured by METTLER
・ Conditions: 10 ° C / min

(3) Composition ratio of each polymer block in each acrylic block copolymer
^It was determined by ¹ H-NMR measurement.
Device: JEOL Nuclear Magnetic Resonance Device “JNM-LA400”
Solvent: deuterated chloroform (CDCl ₃ )

(4) Light transmittance The light transmittance was measured according to JIS K-6714. Using the resin compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 3, a measurement sample was prepared from a 1 mm thick press plate obtained by press molding at 200 ° C. for 3 minutes. The measurement temperature is 23 ° C. The greater the value, the better the transparency.

(5) Haze value In accordance with JIS K-7105, a measurement sample was prepared from the press plate used in the light transmittance measurement of (4) above and measured at room temperature. The smaller the value, the better the transparency.

(6) Charpy impact strength (impact resistance)
Charpy impact strength was measured according to JIS K7111. Using the resin compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 3, samples for measurement were prepared from press plates having a thickness of 3 mm obtained by press molding at 200 ° C. for 3 minutes. The measurement temperature is 23 ° C. The larger the value, the better the impact resistance.

Synthesis Example 1 [Preparation of Organoaluminum Compound: Isobutylbis (2,6-di-t-butyl-4-methylphenoxy) aluminum]
After drying with sodium, 25 ml of dry toluene obtained by distillation under an argon atmosphere and 11 g of 2,6-di-t-butyl-4-methylphenol were added to a 200 ml flask whose inside was replaced with argon. And stirred at room temperature to prepare a uniform solution. 6.8 ml of triisobutylaluminum was added to the resulting solution and stirred at 80 ° C. for about 1 hour, whereby isobutylbis (2,6-di-t-butyl-4-methylphenoxy) aluminum was added at 0.7 mmol / A toluene solution containing a concentration of g was prepared.

[Synthesis Example 2] [Synthesis of acrylic block copolymer (B-1)]
Into a two-necked flask having a volume of 2 liters, the inside of which was replaced with nitrogen, 1040 g of dry toluene, 100 g of 1,2-dimethoxyethane, and isobutyl bis (2,6-di-t-butyl prepared in Synthesis Example 1) were stirred at room temperature. 30 g of toluene solution containing 21 mmol of (-4-methylphenoxy) aluminum was added, and further 8.0 mmol of sec-butyllithium was added to prepare a mixed solution. After adding 52 g of methyl methacrylate to this liquid mixture and making it react at room temperature for 1 hour, 0.1 g of reaction liquid was extract | collected (sampling sample 1). Subsequently, the internal temperature of the reaction solution was cooled to −25 ° C., and 347 g of acrylic n-butyl was added dropwise over 2 hours. After completion of dropping, 0.1 g of the reaction solution was collected (sampling sample 2). Subsequently, 52 g of methyl methacrylate was added, and the reaction solution was returned to room temperature and stirred for 8 hours. The polymerization was stopped by adding 4 g of methanol to the reaction solution. The reaction solution after termination of the polymerization was poured into a large amount of methanol to obtain a deposited precipitate (sampling sample 3). Sampling samples 1 to 3 were subjected to the above measurements, and from these measurement results, Mw (weight average molecular weight), Mw / Mn (molecular weight distribution), and methacrylic acid of the obtained acrylic block copolymer (B-1). The weight ratio of the methyl polymer (PMMA) block and the n-butyl acrylate polymer (PnBA) block was determined. As a result, the resulting acrylic block copolymer (B-1) was a triblock copolymer composed of PMMA block-PnBA block-PMMA block (bonding form: (b2)-(b1)-(b2)). Met. The measurement results are shown in Table 1.

[Synthesis Example 3] [Synthesis of acrylic block copolymer (B-2)]
In a two-necked flask having a volume of 2 liters, the inside of which was replaced with nitrogen, 1040 g of dry toluene, 100 g of 1,2-dimethoxysilane, and isobutyl bis (2,6-di-t-butyl) prepared in Synthesis Example 1 were stirred at room temperature. 66 g of a toluene solution containing 46 mmol of (-4-methylphenoxy) aluminum was added, and 10 mmol of sec-butyllithium was further added to prepare a mixed solution. After adding 68 g of methyl methacrylate to this mixed solution and reacting at room temperature for 1 hour, 0.1 g of the reaction solution was collected (sampling sample 4). Subsequently, the internal temperature of the reaction solution was cooled to −25 ° C., and 249 g of n-butyl acrylate was added dropwise over 2 hours. After completion of dropping, 0.1 g of the reaction solution was collected (sampling sample 5). Subsequently, 68 g of methyl methacrylate was added, and the reaction solution was returned to room temperature and stirred for 8 hours. The polymerization was stopped by adding 4 g of methanol to the reaction solution. The reaction liquid after termination of the polymerization was poured into a large amount of methanol to obtain a deposited precipitate (sampling sample 6). Sampling samples 4 to 6 were subjected to the above measurement, and Mw (weight average molecular weight), Mw / Mn (molecular weight distribution), methyl methacrylate polymer (PMMA) of the obtained acrylic block copolymer (B-2). ) The weight ratio of block and acrylic acid n-butyl polymer (PnBA) block was determined. As a result, the resulting acrylic block copolymer (B-2) was a triblock copolymer (bonding form: (b2)-(b1)-(b2)) consisting of PMMA block-PnBA block-PMMA block. Met. The measurement results are shown in Table 1.

[Synthesis Example 4] [Synthesis of acrylic block copolymer (B-3)]
Into a two-necked flask having a volume of 2 liters, the inside of which was replaced with nitrogen, 1040 g of dry toluene, 100 g of 1,2-dimethoxyethane, and isobutyl bis (2,6-di-t-butyl prepared in Synthesis Example 1) were stirred at room temperature. 66 g of a toluene solution containing 46 mmol of (-4-methylphenoxy) aluminum was added, and 10 mmol of sec-butyllithium was further added to prepare a mixed solution. After adding 69 g of methyl methacrylate to this mixed solution and reacting at room temperature for 1 hour, 0.1 g of the reaction solution was collected (sampling sample 7). Subsequently, the internal temperature of the reaction solution was cooled to −25 ° C., and 194 g of n-butyl acrylate was added dropwise over 2 hours. After completion of dropping, 0.1 g of the reaction solution was collected (sampling sample 8). Subsequently, 173 g of methyl methacrylate was added, and the reaction solution was returned to room temperature and stirred for 8 hours. Polymerization was stopped by adding 4 g of methanol to the reaction solution. The reaction solution after the termination of the polymerization was poured into a large amount of methanol to obtain a deposited precipitate (sampling sample 9). Sampling samples 7 to 9 were measured as described above, and Mw (weight average molecular weight), Mw / Mn (molecular weight distribution), methyl methacrylate polymer (PMMA) of the obtained acrylic block copolymer (B-3). ) The weight ratio of the block to the acrylic acid n-butyl polymer (PnBA) block was determined. As a result, the resulting acrylic block copolymer (B-3) was a triblock copolymer composed of PMMA block-PnBA block-PMMA block (bonding form: (b2)-(b1)-(b2)). Met. The measurement results are shown in Table 1.

[Example 1]
100 parts by mass of a vinyl chloride resin (degree of polymerization 800), 3 parts by mass of the acrylic block copolymer (B-1) shown in Table 1 and a lubricant (Lycowax OP: a mixture of montanic acid ester and calcium montanate) 0 .5 parts by mass, 0.8 parts by mass of lead stearate, 0.6 parts by mass of barium stearate and 1.8 parts by mass of tribasic lead sulfate were mixed with a mixer, and the resulting mixture was mixed with a roll at 190 ° C. The resin composition was prepared by kneading for 3 minutes. The physical properties (light transmittance, haze value and Charpy impact strength) of the obtained resin composition were measured by the method described above. The results are shown in Table 2.

[Example 2]
A resin composition was prepared in the same manner as in Example 1 except that the amount of the acrylic block copolymer (B-1) added was 7 parts by mass, and the physical properties were measured. The results are shown in Table 2.

[Example 3]
A resin composition was prepared in the same manner as in Example 1 except that the addition amount of the acrylic block copolymer (B-1) was 15 parts by mass, and the physical properties were measured. The results are shown in Table 2.

[Example 4]
A resin composition was prepared in the same manner as in Example 1 except that the acrylic block copolymer (B-1) was replaced with the acrylic block copolymer (B-2), and the physical properties were measured. The results are shown in Table 2.

[Example 5]
A resin composition was prepared in the same manner as in Example 1 except that the acrylic block copolymer (B-1) was replaced with the acrylic block copolymer (B-3), and the physical properties were measured. The results are shown in Table 2.

[Comparative Example 1]
100 parts by mass of a vinyl chloride resin (degree of polymerization 800), 0.5 parts by mass of a lubricant (Lycowax OP: a mixture of montanic acid ester and calcium montanate), 0.8 parts by mass of lead stearate, 0.6 barium stearate After mixing parts by mass and 1.8 parts by mass of tribasic lead sulfate with a mixer, the resulting mixture was kneaded with a roll at 190 ° C. for 3 minutes to prepare a resin composition. The physical properties (light transmittance, haze value and Charpy impact strength) of the obtained resin composition were measured by the method described above. The results are shown in Table 2.

[Comparative Example 2]
A resin composition was prepared in the same manner as in Example 1 except that the amount of the acrylic block copolymer (B-1) added was 1 part by mass, and the physical properties were measured. The results are shown in Table 2.

[Comparative Example 3]
A resin composition was prepared in the same manner as in Example 1 except that the amount of the acrylic block copolymer (B-1) added was 20 parts by mass, and the physical properties were measured. The results are shown in Table 2.

  From Table 2, the molded body using the vinyl chloride resin composition of the present invention of Examples 1 to 5 is the molded body of Comparative Example 1 in which the light transmittance and haze value consist only of vinyl chloride resin as the polymer component. It can be seen that it has the same transparency, and the impact resistance is greatly improved. From this, it is clear that the vinyl chloride resin composition of the present invention has an excellent balance between transparency and impact resistance. On the other hand, in Comparative Example 2 in which the content of the acrylic block copolymer is too less than the definition of the present invention, although the transparency is maintained, the impact resistance is poor and the impact resistance improving effect is hardly seen. Moreover, in Comparative Example 3 in which the content of the acrylic block copolymer is too much as defined in the present invention, the impact resistance is improved, but the transparency is inferior.

  Since the transparent vinyl chloride resin composition of the present invention is superior in balance of mechanical properties such as transparency and impact resistance as compared with a single vinyl chloride resin, not only pipes, plates, sheets, films, containers, etc. It is useful as a structural member for indoor and outdoor use, civil engineering and building materials.

Claims (8)

  A chloride containing a vinyl chloride resin (A) and an acrylic block copolymer (B) having a polymer block (b1) composed of acrylate units and a polymer block (b2) composed of methacrylate units. A transparent vinyl chloride resin composition comprising 3 to 15 parts by mass of an acrylic block copolymer (B) with respect to 100 parts by mass of a vinyl chloride resin (A).   The transparent vinyl chloride resin composition according to claim 1, wherein the polymer block (b1) has a glass transition temperature of 25 ° C or lower and the polymer block (b2) has a glass transition temperature of 60 ° C or higher.   The transparent vinyl chloride resin composition according to claim 1 or 2, wherein the acrylic block copolymer (B) is a triblock copolymer in which the polymer block (b2) is bonded to both ends of the polymer block (b1). object.   The transparent vinyl chloride resin composition according to any one of claims 1 to 3, wherein a content ratio of the polymer block (b1) constituting the acrylic block copolymer (B) is 80 to 40% by mass.   The transparent vinyl chloride resin composition according to any one of claims 1 to 4, wherein the molecular weight distribution of the acrylic block copolymer (B) is in the range of 1.0 to 1.4.   The transparent vinyl chloride resin composition according to any one of claims 1 to 5, wherein the acrylic block copolymer (B) has a weight average molecular weight in the range of 10,000 to 200,000.   The transparent vinyl chloride according to any one of claims 1 to 6, wherein the polymer block (b2) constituting the acrylic block copolymer (B) has a weight average molecular weight in the range of 2,000 to 100,000. -Based resin composition.   A molded article comprising the transparent vinyl chloride resin composition according to any one of claims 1 to 7.