JP2000264936A - Vinyl chloride-based resin and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vinyl chloride-based resin having excellent impact resistance and weatherability. SOLUTION: This vinyl chloride-based resin is composed of a resin comprising polyvinyl chloride as a main component in which an acrylic copolymer obtained by graft polymerizing vinyl chloride is dispersed and the acrylic copolymer has a core-shell double layer structure, and the core part of the acrylic copolymer is mainly composed of a poly(meth)acrylate having a glass transition point of from -140 deg.C to -20 deg.C and the shell part of the acrylic copolymer is mainly composed of polyorganosiloxane and a grafting ratio of the vinyl chloride is 0.1-5 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vinyl chloride resin and a method for producing the vinyl chloride resin.

[0002]

2. Description of the Related Art Conventionally, vinyl chloride resins have been used in many applications as materials having excellent mechanical strength, weather resistance and chemical resistance. However, when used for hard materials, they have a disadvantage of poor impact resistance, and various improvement methods have been proposed. For example, JP-A-60-2558
No. 13 discloses a vinyl chloride resin obtained by graft-polymerizing an acrylic copolymer and vinyl chloride as a vinyl chloride resin particularly used for applications requiring impact resistance.

In Japanese Patent Application Laid-Open Nos. Hei 7-286016 and Hei 9-255705, as a method for improving the weather resistance of a vinyl chloride resin, vinyl chloride is added to an acrylic copolymer containing polyorganosiloxane. Blended or graft polymerized vinyl chloride resins are disclosed. However, even in a vinyl chloride resin using such an acrylic copolymer, the interface between the vinyl chloride matrix and the acrylic copolymer is mainly composed of poly (meth) acrylate, so that the polyorganosiloxane is used. The effect of improving weather resistance was not sufficient.

Japanese Patent Publication No. 5-22724 discloses a method in which a vinyl monomer is graft-polymerized to a polyorganosiloxane. However, if this method is used to obtain a vinyl chloride resin having high impact resistance, However, since a large amount of silicone rubber is required, there is a problem that the cost is very high. At present, a vinyl chloride resin having such excellent impact resistance and weather resistance has not been provided.

[0005]

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a vinyl chloride resin excellent in impact resistance and weather resistance and a method for producing the same.

[0006]

According to the present invention, there is provided a vinyl chloride resin in which an acrylic copolymer obtained by graft polymerization of vinyl chloride is dispersed in a resin containing polyvinyl chloride as a main component. The union is a vinyl chloride resin having a core-shell two-layer structure, and the core of the acrylic copolymer has a glass transition temperature of -140.
The copolymer is composed of a copolymer mainly composed of poly (meth) acrylate having a temperature of not lower than -20 ° C. and less than −20 ° C. The shell of the acrylic copolymer is composed of a copolymer composed mainly of polyorganosiloxane, The graft ratio of vinyl is 0.1.
1 to 5% by weight.

Further, according to the method for producing a vinyl chloride resin of the present invention, the glass transition temperature of the homopolymer is −140 ° C. or higher.
30 to 90% by weight of a copolymer comprising 100 parts by weight of a polymerizable monomer having a (meth) acrylate as a main component at a temperature of less than 20 ° C. and 0.3 to 20 parts by weight of an organosiloxane having a radically polymerizable unsaturated double bond. And an acrylic siloxane by graft polymerization of 100 parts by weight of an organosiloxane and 0.3 to 20 parts by weight of a mixed organosiloxane having a radical polymerizable unsaturated double bond. After producing the polymer, the obtained acrylic copolymer is graft-polymerized with a vinyl monomer containing vinyl chloride as a main component. Hereinafter, the present invention will be described in detail.

The vinyl chloride resin of the present invention is obtained by dispersing an acrylic copolymer obtained by graft polymerization of vinyl chloride in a resin containing polyvinyl chloride as a main component.

The acrylic copolymer has a core-shell two-layer structure, and the core is mainly composed of poly (meth) acrylate having a glass transition temperature of −140 ° C. or more and less than −20 ° C. It is made of a copolymer, and the shell part is
It is composed of a copolymer containing polyorganosiloxane as a main component.

[0010] The glass transition temperature of the core portion is-
A copolymer mainly composed of poly (meth) acrylate having a temperature of 140 ° C. or higher and lower than −20 ° C. is blended to improve the impact resistance of the vinyl chloride resin by forming the acrylic copolymer. The glass transition temperature is limited to the above range since the glass transition temperature requires flexibility at room temperature. When the glass transition temperature is less than -140 ° C, it is not suitable as a polymer generally used industrially,
At -20 ° C or higher, it is difficult to impart sufficient flexibility to the vinyl chloride resin.

The above-mentioned copolymer containing poly (meth) acrylate as a main component may be a homopolymer or a copolymer of (meth) acrylate monomer, or a mixture of (meth) acrylate monomer and (meth) acrylate monomer. It is a copolymer with another copolymerizable monomer.

The above (meth) acrylate monomers include, for example, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl (meth) acrylate, iso-butyl acrylate, sec.
-Butyl acrylate, cumyl acrylate, n-hexyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, 2-methylheptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n -Nonyl (meth) acrylate, 2-methyloctyl (meth) acrylate, 2-
Examples include alkyl (meth) acrylates such as ethyl (meth) heptyl acrylate, n-decyl (meth) acrylate, and lauryl (meth) acrylate; 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and the like. These may be used alone or in combination of two or more. The glass transition temperature of the homopolymer of the (meth) acrylate monomer (A) can be determined by referring to “Polymer Data Handbook (Basic)” edited by The Society of Polymer Science
986, Baifukan).

Examples of the other monomer include a radical polymerizable monomer, a polyfunctional monomer, and an organosiloxane containing a radical polymerizable unsaturated double bond. These may be used alone or in combination of two or more. These monomers will be described below.

Examples of the radical polymerizable monomer include methyl (meth) acrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, sec-butyl methacrylate, and t-butyl methacrylate.
Butyl (meth) acrylate, cumyl methacrylate,
n-hexyl methacrylate, cyclohexyl (meth)
Alkyl (meth) acrylates such as acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, and stearyl (meth) acrylate; polar groups such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and 2-acryloyloxyethyl phthalic acid Vinyl monomers; aromatic vinyl monomers such as styrene, α-methylstyrene, p-methylstyrene and p-chlorostyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; vinyl esters such as vinyl acetate and vinyl propionate; No. These may be used alone or in combination of two or more.

The amount of the radical polymerizable monomer is as follows:
From 0 to 49 parts by weight of the radical polymerizable monomer is preferred based on 51 to 100 parts by weight of the (meth) acrylate. If the amount of the radical polymerizable monomer exceeds 49 parts by weight, the flexibility of the core may be lost, and the impact resistance of the vinyl chloride resin may be reduced. By using the radical polymerizable monomer, the mechanical strength of the vinyl chloride resin,
Chemical resistance and moldability can be further improved.

As the polyfunctional monomer (D), for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) Di (meth) acrylates such as acrylate and trimethylolpropane di (meth) acrylate; trimethylolpropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate (Meth) acrylate;
Pentaeristol tetra (meth) acrylate, dipentaeristol hexa (meth) acrylate; di- or triallyl compounds such as diallyl phthalate, diallyl maleate, diallyl fumarate, diallyl succinate, triallyl isocyanurate; divinylbenzene, butadiene, etc. And the like. These may be used alone or in combination of two or more.

The amount of the polyfunctional monomer is preferably from 0 to 30 parts by weight based on 100 parts by weight of the total of the (meth) acrylate monomer and the radical polymerizable monomer. When the blending amount of the polyfunctional monomer is 30
If the amount is more than 100 parts by weight, the cross-linking density of the copolymer containing poly (meth) acrylate as a main component becomes high, so that impact resistance may not be obtained. More preferably, it is 0 to 10 parts by weight.

By using the above polyfunctional monomer, the copolymer forming the core can be crosslinked, and the impact resistance of the vinyl chloride resin can be improved. Furthermore, coalescence of the particles comprising the copolymer constituting the core part during and after the production can be made less likely to occur.

Examples of the organosiloxane having a radically polymerizable unsaturated double bond include, for example, organosiloxanes represented by the following general formulas (1) to (3).

[0020]

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(Wherein, R ¹ represents a methyl group or a hydrogen atom, R ² represents a methyl group or an ethyl group, n represents an integer of 0 to 3, x represents an integer of 1 to 4, y represents Represents an integer of 1 to 10.) Specific examples of the organosiloxane having a radically polymerizable unsaturated double bond include, for example, γ-acryloyloxypropyltrimethoxysilane.

The content of the above-mentioned organosiloxane having a radical polymerizable unsaturated double bond is as follows.
It is preferably 0.3 to 20 parts by weight based on 100 parts by weight of the total amount of the acrylate, the radical polymerizable monomer and the polyfunctional monomer. If the amount of the organosiloxane having a radical polymerizable unsaturated double bond is less than 0.3 parts by weight, the acrylic copolymer hardly undergoes a graft copolymerization reaction of the organosiloxane, and a core-shell structure is formed. Since it cannot be obtained, impact resistance may decrease,
When the amount exceeds 20 parts by weight, polymerization occurs between the organosiloxanes having the radically polymerizable unsaturated double bond, so that the glass transition temperature of the core may become -20 ° C or higher, and the flexibility is reduced. , It is difficult to obtain impact resistance.

By using the above-mentioned organosiloxane having a radically polymerizable unsaturated double bond, the copolymer containing poly (meth) acrylate as a main component can be copolymerized with the polyorganosiloxane serving as a shell portion as a main component. The polymer can be graft polymerized. Therefore, the organosiloxane having a radically polymerizable unsaturated double bond serves as a graft crossing agent.

The above-mentioned copolymer containing poly (meth) acrylate as a main component may be obtained using the above-mentioned monomer component as a raw material. Among them, the above-mentioned (meth) acrylate, the above-mentioned radical polymerizable monomer, Copolymers containing a functional monomer and the above-mentioned organosiloxane having a radically polymerizable unsaturated double bond as raw material components are preferred.

The shell portion is made of a copolymer containing an organosiloxane as a main component. By using an organosiloxane, the weather resistance of the vinyl chloride resin of the present invention can be improved. The copolymer containing the above-mentioned organosiloxane as a main component is a copolymer of the above-mentioned organosiloxane and an organosiloxane having a radically polymerizable unsaturated double bond.

The above-mentioned organosiloxane is not particularly limited, but a cyclic organosiloxane is preferred from the viewpoint of excellent operability in the step of producing a vinyl chloride resin. Examples of such a cyclic organosiloxane include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane, Octaphenylcyclotetrasiloxane and the like can be mentioned. These may be used alone or in combination of two or more.

Examples of the organosiloxane having a radically polymerizable unsaturated double bond include those similar to those described as the other monomer forming the core.

The amount of the organosiloxane having a radically polymerizable unsaturated double bond to be mixed with the organosiloxane having a radically polymerizable unsaturated double bond is from 0.3 to 20 parts by weight based on 100 parts by weight of the organosiloxane. Parts by weight are preferred. When the amount of the organosiloxane having a radically polymerizable unsaturated double bond is less than 0.3 parts by weight, the graft polymerization point of vinyl chloride on the acrylic copolymer is reduced, so that the impact resistance of the vinyl chloride resin is reduced. May worsen, and if it exceeds 20 parts by weight,
Since polymerization of the organosiloxanes having the radical polymerizable unsaturated double bond occurs, the polymerizability of the shell may decrease. More preferably, it is 1 to 5 parts by weight. Vinyl chloride can be graft-polymerized to the organosiloxane having a radical polymerizable unsaturated double bond constituting the shell portion of the acrylic copolymer having the core-shell two-layer structure. That is, the organosiloxane having a radically polymerizable unsaturated double bond can function as a graft crossing agent.

The mixing ratio of the copolymer constituting the core part and the copolymer constituting the shell part is determined by the ratio of the core part 3
The shell portion is preferably 10 to 70% by weight with respect to 0 to 90% by weight. If the core portion is less than 30% by weight, sufficient impact resistance may not be obtained, and
If it is less than 0% by weight, sufficient weather resistance may not be obtained.

The method for producing the acrylic copolymer having such a core-shell two-layer structure is not particularly limited, and examples thereof include an emulsion polymerization method and a suspension polymerization method. Among these, the emulsion polymerization method is preferred because it has good impact resistance and easily controls the particle size of the acrylic copolymer.

The vinyl chloride resin of the present invention is obtained by dispersing the above acrylic copolymer obtained by graft polymerization of vinyl chloride at a graft ratio of 0.1 to 5% by weight in a resin containing polyvinyl chloride as a main component. I have. The resin containing polyvinyl chloride as a main component is composed of a homopolymer of vinyl chloride or a copolymer of 50% by weight or more of vinyl chloride and a vinyl monomer copolymerizable with the vinyl chloride.

The copolymerizable vinyl monomer is not particularly limited as long as it is copolymerizable with vinyl chloride. Examples thereof include vinyl acetate, alkyl (meth) acrylate, alkyl vinyl ether, ethylene, vinyl fluoride, and maleimide. And the like. These vinyl monomers may be used alone or in combination of two or more.

The mixing ratio of the acrylic copolymer in the vinyl chloride resin is not particularly limited.
0% by weight is preferred. When the blending ratio of the acrylic copolymer is less than 1% by weight, the impact resistance of the molded product is reduced when the vinyl chloride resin is used for a molded product such as a rigid vinyl chloride tube or a molded article. May be 30% by weight
When the ratio exceeds the above, the mechanical strength of the molded article may be reduced. More preferably, it is 3 to 16% by weight.

The above-mentioned graft ratio of vinyl chloride means the weight fraction of vinyl chloride molecules which are copolymerized with the acrylic copolymer and chemically bonded.

If the vinyl chloride graft ratio is less than 0.1% by weight, the surface of the acrylic copolymer cannot be sufficiently covered with vinyl chloride molecules. At the time of production, a molded product having a good surface condition cannot be obtained. If the content exceeds 5% by weight, characteristics such as impact resistance are not easily improved, so the content is limited to the above range.

As described above, in the vinyl chloride resin of the present invention, the core of the acrylic copolymer having a core-shell two-layer structure is made of a highly flexible (meth) acrylate-based copolymer. Therefore, the vinyl chloride resin of the present invention is excellent in impact resistance and mechanical strength. In addition, the shell portion of the acrylic copolymer is made of a copolymer containing an organosiloxane as a main component, and is capable of preventing the deterioration of the acrylic copolymer due to hydrogen chloride generated due to photodegradation of vinyl chloride. Therefore, the vinyl chloride resin of the present invention is excellent in weather resistance.

The method for producing the vinyl chloride resin using the acrylic copolymer and the resin containing polyvinyl chloride as a main component is not particularly limited, and examples thereof include a suspension polymerization method and an emulsion polymerization method. , A solution polymerization method, a bulk polymerization method and the like. Further, the vinyl chloride resin of the present invention can also be produced by using the production method of the present invention 2 described below.

In the method for producing a vinyl chloride resin according to the second aspect of the present invention, the homopolymer has a glass transition temperature of -140 ° C. or higher.
30 to 90% by weight of a copolymer composed of 100 parts by weight of a polymerizable monomer having a (meth) acrylate as a main component at a temperature of less than 0 ° C. and 0.3 to 20 parts by weight of an organosiloxane having a radical polymerizable unsaturated double bond. And an acrylic siloxane by graft polymerization of 100 parts by weight of an organosiloxane and 0.3 to 20 parts by weight of a mixed organosiloxane having a radical polymerizable unsaturated double bond. After producing the polymer, a vinyl monomer containing vinyl chloride as a main component is graft-polymerized to the obtained acrylic copolymer.

In the above-mentioned method for producing a vinyl chloride resin, first, a polymerizable monomer mainly composed of (meth) acrylate having a glass transition temperature of −140 ° C. or higher and lower than −20 ° C. and a radical polymerizable monomer are used. An acrylic copolymer obtained by graft-polymerizing a mixed organosiloxane composed of an organosiloxane and an organosiloxane having a radically polymerizable unsaturated double bond onto a copolymer composed of an organosiloxane having a saturated double bond. Get.

Specifically, 100 parts by weight of the polymerizable monomer containing the above (meth) acrylate as a main component and 0.3 parts of an organosiloxane having a radical polymerizable unsaturated double bond are used.
To 20 parts by weight into a polymerization system and copolymerized to obtain a copolymer. Further, 30 to 90% by weight of the obtained copolymer and 10 to 70% by weight of the mixed organosiloxane.
Is charged into a polymerization system, and graft polymerization is performed to produce an acrylic copolymer. The acrylic copolymer thus obtained has a core composed of a copolymer composed of a polymerizable monomer and an organosiloxane having a radically polymerizable unsaturated double bond, and a copolymer composed of a mixed organosiloxane. It has a core-shell two-layer structure as a shell part.

The production of the core part and the shell part of the acrylic copolymer may be carried out in a series of polymerization steps. Alternatively, first, a polymerization step for producing the core part is carried out, recovered, and then recovered. A polymerization step of adding a monomer to the copolymer to produce a shell portion may be performed.

The polymerizable monomer may be composed of (meth) acrylate alone having a glass transition temperature of a homopolymer of −140 ° C. or more and less than −20 ° C., or may be composed of the (meth) acrylate and the (meth) acrylate. It may be composed of an acrylate and another copolymerizable monomer.

Examples of the (meth) acrylate include those similar to the (meth) acrylate used in the first aspect of the present invention. These may be used alone or in combination of two or more. Examples of the other monomer include a radical polymerizable monomer and a polyfunctional monomer.

Examples of the radical polymerizable monomer include those similar to the radical polymerizable monomer used in the present invention 1. These may be used alone,
Two or more kinds may be used in combination. Examples of the polyfunctional monomer include those similar to the polyfunctional monomer used in the first aspect of the present invention. These may be used alone,
Two or more kinds may be used in combination.

Examples of the organosiloxane having a radically polymerizable unsaturated double bond include those similar to the organosiloxane having a radically polymerizable unsaturated double bond used in the present invention 1. These may be used alone or in combination of two or more.

The above-mentioned acrylic copolymer may be produced in a series of polymerization steps, or may be prepared by an emulsion polymerization method or a suspension method, regardless of whether the step of producing the core and the step of producing the shell are separate. It can be carried out using a polymerization method such as a turbid polymerization method. Among them, the emulsion polymerization method is preferred because it has good impact resistance and easily controls the particle size of the acrylic copolymer. In addition, the said copolymer means all copolymerizations, such as random copolymerization, block copolymerization, and Glast copolymerization.

The above-mentioned emulsion polymerization can be carried out by a conventionally known method. For example, if necessary, an emulsifying dispersant, a polymerization initiator, a pH adjuster, an antioxidant and the like may be added.

The above-mentioned emulsifying dispersant is used to improve the dispersion stability of the monomer component in the emulsion and to carry out the polymerization efficiently. The emulsifying dispersant is not particularly limited, and examples thereof include anionic surfactants, nonionic surfactants, partially saponified polyvinyl alcohol, cellulose dispersants, and gelatin. Among these, anionic surfactants are preferable, and more specifically, polyoxyethylene alkylphenyl ether sulfate and the like are preferable when the core is produced, and sodium alkylbenzene sulfonate is used when the shell is produced. preferable.

The above-mentioned polymerization initiator is not particularly limited, but when the core is produced, for example, a water-soluble polymerization initiator such as ammonium persulfate, potassium persulfate, hydrogen peroxide, etc .; benzoyl peroxide, lauroyl peroxide Organic peroxides such as; azo-based polymerization initiators such as azobisisobutyronitrile; polymerization initiators that generate free radicals such as redox polymerization initiators are preferable; Acids and alkalis such as sulfuric acid, hydrochloric acid, alkylbenzenesulfonic acid, sodium hydroxide and potassium hydroxide are preferred.

The type of the emulsion polymerization method is not particularly limited.
For example, a batch polymerization method, a monomer dropping method, an emulsion dropping method and the like can be mentioned.

In the above batch polymerization method, pure water, an emulsifying dispersant, and a mixed monomer are added all at once to a jacketed polymerization reactor, and the mixture is stirred under a nitrogen stream and sufficiently emulsified. This is a method in which the inside is heated to a predetermined temperature by a jacket and then polymerized.

In the above monomer dropping method, pure water, an emulsifying dispersant, and a polymerization initiator are charged into a polymerization reactor equipped with a jacket, oxygen is removed under a stream of nitrogen, and pressurization is performed. This is a method in which after the temperature is raised to a temperature, the mixed monomer is added dropwise in a fixed amount to carry out polymerization.

In the emulsion dropping method, an emulsion monomer is prepared in advance by stirring a mixed monomer, an emulsifying dispersant, and pure water, and then pure water and a polymerization initiator are charged into a jacketed polymerization reactor. After removing oxygen and pressurizing under a nitrogen gas flow, the inside of the reactor is heated to a predetermined temperature, and then the above-mentioned emulsified monomer is added dropwise in a predetermined amount to carry out polymerization.

In the emulsion dropping method, a method in which a part of the emulsifying monomer is added all at once in the early stage of polymerization and then the remaining emulsifying monomer is added dropwise can be used by changing the amount of the emulsifying monomer added in a lump. In addition, the particle size of the resulting acrylic copolymer can be easily controlled.

Among these, a monomer dropping method and an emulsion dropping method, which are preferably used for producing particles having a core-shell structure, are preferred.

In the polymerization method as described above, the solid content ratio of the acrylic copolymer obtained after the completion of the reaction is not particularly limited. However, from the viewpoint of the productivity of the acrylic copolymer and the stability of the polymerization reaction, the solid content ratio is 10 to 10%. 60% by weight is preferred. In the polymerization method as described above, a protective colloid or the like may be added for the purpose of improving the mechanical stability of the acrylic copolymer (E) after the completion of the reaction.

The average particle size of the acrylic copolymer particles is not particularly limited, but is preferably from 10 to 500 nm. If it is less than 10 nm, the rate of occurrence of impact resistance may decrease, and if it exceeds 500, both the impact resistance and tensile strength of the molded article may decrease. Preferably, 50 to 2
00 nm.

In the method for producing a vinyl chloride resin according to the present invention, 1 to 30 parts by weight of the acrylic copolymer and 99 to 70 parts by weight of a vinyl monomer are mixed and graft-polymerized. When the amount of the acrylic copolymer is less than 1 part by weight, the impact resistance of the obtained molded article of the vinyl chloride resin may decrease. When the amount exceeds 30 parts by weight, the mechanical strength of the molded article decreases. There are cases. The amount of the acrylic copolymer is preferably 3 to 16 parts by weight.

In the production method of the present invention, a vinyl monomer containing vinyl chloride as a main component is graft-polymerized to the acrylic copolymer. The resin containing polyvinyl chloride as the main component is the same as the resin containing polyvinyl chloride as the main component used in the first aspect of the invention.

The method for the graft polymerization is not particularly limited, and examples thereof include a suspension polymerization method, an emulsion polymerization method, a solution polymerization method, and a bulk polymerization method. Among these,
The suspension polymerization method is preferred.

When performing polymerization by the above suspension polymerization method,
A dispersant, an oil-soluble polymerization initiator, or the like may be used. By using the dispersant, the dispersion stability of the acrylic copolymer in the polymerization system can be improved, and the graft polymerization of the hinyl monomer can be performed efficiently. The dispersant is not particularly limited, and includes, for example, poly (meth) acrylate, (meth) acrylate / alkyl acrylate copolymer, methylcellulose, ethylcellulose, hydroxypropylmethylcellulose, polyethylene glycol, polyvinyl acetate and parts thereof. Examples include saponified products, gelatin, polyvinylpyrrolidone, starch, maleic anhydride / styrene copolymer, and the like. These may be used alone or in combination of two or more.

The oil-soluble polymerization initiator is not particularly limited, but a radical polymerization initiator is preferable. Examples of such an oil-soluble polymerization initiator include lauroyl peroxide, t-butylperoxypivalate, and diisopropylperoxide. Organic peroxides such as oxydicarbonate, dioctyl peroxy dicarbonate, t-butyl peroxy neodecanoate and α-cumyl peroxy neodecanoate; 2,2-azobisisobutyronitrile, 2,2 And azo compounds such as -azobis-2,4-dimethylvaleronitrile.

When the vinyl chloride is graft-polymerized, a coagulant is added to the dispersion solution of the acrylic copolymer (E) in order to reduce the scale adhering to the polymerization tank during the polymerization. You may. Further, if necessary, p
An H adjuster, an antioxidant and the like may be added.

As the above suspension polymerization method, for example, the following method can be used. That is, a temperature controller, and a polymerization vessel equipped with a stirrer, pure water, the dispersant, the oil-soluble polymerization initiator, the acrylic copolymer, and, if necessary, a water-soluble thickener, the degree of polymerization control After a dispersion solution comprising the agent is charged and air is removed from the inside of the polymerization vessel by a vacuum pump, vinyl chloride and / or other vinyl monomers are introduced into the polymerization vessel under stirring conditions. Thereafter, the temperature inside the reaction vessel is raised, and graft polymerization is performed at a desired polymerization temperature. At this time,
The polymerization temperature is preferably 30 to 90 ° C, and the polymerization time is 2 to 2
0 hours is preferred.

In the above suspension polymerization method, the temperature in the reaction vessel, that is, the polymerization temperature can be controlled by changing the jacket temperature. After completion of the reaction, a vinyl chloride-based graft copolymer can be obtained by removing unreacted vinyl chloride containing vinyl chloride as a main component to form a slurry, and then performing dehydration drying.

The polymerization degree of the vinyl chloride is 300 to 20.
00 is preferred. When the degree of polymerization is less than 300 or 16
If it exceeds 00, the moldability when molding the vinyl chloride-based graft copolymer produced by using the production method of the present invention may be poor. More preferably, it is 400 to 1600. By using such a manufacturing method, a vinyl chloride resin having excellent impact resistance and weather resistance can be manufactured.

The molded article can be obtained by molding the vinyl chloride resin of the present invention 1 or the vinyl chloride resin produced by the production method of the present invention 2. When obtaining the molded article, if necessary, heat stabilizer, stabilization aid, lubricant, processing aid, antioxidant, light stabilizer, filler,
A compounding agent such as a pigment may be added.

The heat stabilizer is not particularly restricted but includes, for example, dimethyltin mercapto, dibutyltin mercapto,
Organic tin stabilizers such as dioctyltin mercapto, dibutyltin malate, dibutyltin malate polymer, dioctyltin malate, dioctyltin malate polymer, dibutyltin laurate, dibutyltin laurate polymer; lead stearate, dibasic phosphorous acid Lead-based stabilizers such as lead and tribasic lead sulfate; calcium-zinc-based stabilizers, barium-zinc-based stabilizers, barium-cadmium-based stabilizers, and the like. These may be used alone or in combination of two or more.

The above stabilizing aid is not particularly limited.
For example, epoxidized soybean oil, epoxidized linseed oil, epoxidized tetrahydrophthalate, epoxidized polybutadiene, phosphate ester and the like can be mentioned. These may be used alone or in combination of two or more.

The lubricant is not particularly restricted but includes, for example, montanic acid wax, paraffin wax, polyethylene wax, stearic acid, stearyl alcohol, butyl stearate and the like. These may be used alone or in combination of two or more.

The processing aid is not particularly limited, and examples thereof include an acrylic processing aid which is an alkyl acrylate / alkyl methacrylate copolymer having a weight average molecular weight of 100,000 to 2,000,000. Specific examples of the processing aid include an n-butyl acrylate / methyl methacrylate copolymer and a 2-ethylhexyl acrylate / methyl methacrylate / butyl methacrylate copolymer. These may be used alone or in combination of two or more.

The antioxidant is not particularly limited.
For example, phenolic antioxidants and the like can be mentioned. These may be used alone or in combination of two or more.

The light stabilizer is not particularly restricted but includes, for example, UV absorbers such as salicylic acid esters, benzophenones, benzotriazoles and cyanoacrylates; and hindered amine light stabilizers.
These may be used alone or in combination of two or more.

The filler is not particularly limited, and examples thereof include calcium carbonate and talc. These may be used alone or in combination of two or more.

The above-mentioned pigments are not particularly restricted but include, for example, organic pigments such as azo, phthalocyanine, sulene and dye lakes; oxides, molybdenum chromates, sulfides / selenides, ferrocyanides. And other inorganic pigments. These may be used alone or in combination of two or more.

When the molded article is obtained, a plasticizer may be added to the vinyl chloride-based graft copolymer for the purpose of improving the processability during molding. The plasticizer is not particularly limited, and examples thereof include dibutyl phthalate, di-2-ethylhexyl phthalate, and di-2-ethylhexyl adipate. These may be used alone or in combination of two or more.

In order to obtain the molded article, a thermoplastic resin such as polyvinyl chloride may be added as necessary. These may be used alone or in combination of two or more.

The method for mixing the above various compounding agents and plasticizers with the vinyl chloride resin is not particularly limited, and examples thereof include a method using hot blending and a method using cold blending. The method for molding the vinyl chloride-based graft copolymer is not particularly limited, and examples thereof include an extrusion molding method, an injection molding method, a calendar molding method, and a press molding method.

As described above, the vinyl chloride resin of the present invention and the vinyl chloride resin produced by the production method of the present invention are excellent in impact resistance and weather resistance, and these properties are balanced. Is very good. Therefore,
By blending the above lubricants, stabilizers, pigments and the like used in the molding process, it is possible to perform the process with good fluidity, and to obtain building members, pipeline products and the like which are constructed outdoors in cold regions. Very useful on. In addition, it can be suitably used for hard vinyl chloride pipes, plastic sashes, soundproof walls, and the like that require excellent mechanical strength, weather resistance, and the like that are excellent in impact resistance by utilizing the above characteristics.

[0080]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Examples 1 to 7Manufacture of acrylic copolymer latex  First, the core emulsifying monomer and the shell milk shown in Table 1
The compounds for the fluorinated monomers were used in the amounts shown in Table 1 respectively.
After mixing, stir and mix the emulsifying monomer for core and shell
Emulsion monomers were separately prepared. Next, display in the polymerization tank
After adding the amount of ion-exchanged water shown in 1 and stirring,
Then, the pressure inside the polymerization tank was reduced to deoxygenate the vessel.
After that, the pressure was replaced by pressure reduction with nitrogen.
The temperature was raised to 70 ° C. After the temperature rise, the reactor is shown in Table 1.
Ammonium persulfate in a mixed amount, and emulsification for the core
30% by weight based on all emulsified monomers among monomers
The amount was charged all at once, and polymerization was started. Then, for the core
The rest of the emulsified monomer was added dropwise over 2 hours.

After the completion of the dropping of the core emulsifying monomer, an aging time of 1 hour was allowed. Thereafter, the temperature of the polymerization tank was raised to 90 ° C., and the emulsion monomer for shell was added dropwise over 3 hours. After an aging time of 2 hours after completion of the dropwise addition, the mixture was cooled to room temperature. After further aging with stirring at room temperature for 12 hours, a 1% aqueous sodium hydroxide solution was added to adjust the pH to 6 to 8, and an acrylic copolymer having a solid concentration of about 27 to 29% by weight was used. A combined latex was obtained. The glass transition temperature of the acrylic copolymer in the obtained acrylic copolymer latex was measured by the following evaluation method, and the results are shown in Table 1.

In the table, n-BA represents n-butyl acrylate, 2-EHA represents 2-ethylhexyl acrylate, TMPTA represents trimethylolpropane triacrylate, and APTMS represents γ-acryloyloxypropyl trimethoxy. Represents silane, N-08
Represents a polyoxyethylene nonylphenyl ether ammonium salt.

In the table, D4 represents octamethylcyclotetrasiloxane, TES represents tetraethoxysilane, ABSNa represents sodium alkylbenzenesulfonate, and DBS represents dodecylbenzenesulfonic acid.

[0085]Evaluation method  (1) Glass transition temperature Using a differential scanning calorimeter (DSC) manufactured by Seiko Instruments Inc.
Measured. Measurement sample is acrylic copolymer latex
Approximately 10 mg of the dried film was used, and the measurement range was -100 to 2
The scanning speed was 5 ° C./min at 5 ° C.

[0086]Manufacture of vinyl chloride resin  Then, the reaction vessel equipped with a stirrer and jacket was
The composition having the composition shown in 1 was charged all at once, and then
Exhaust air from the reactor with a pump,
After introducing vinyl chloride, the weight is controlled by controlling the jacket temperature.
Polymerization was started at a total temperature of 57 ° C.

The completion of the reaction was confirmed when the pressure in the reactor was reduced to a pressure of 6.0 kg / cm ² , and the reaction was stopped. After that, unreacted vinyl chloride monomer is removed,
Further, by performing dehydration drying, a vinyl chloride resin having a polymerization degree of vinyl chloride in the vinyl chloride resin of about 1000 was obtained. The graft ratio, impact resistance and weather resistance of the obtained vinyl chloride resin were measured by the following evaluation methods, and the results are shown in Table 1.

In the tables, PVA represents partially saponified polyvinyl acetate, MPS represents hydroxypropylmethylcellulose, BPOND represents t-butylperoxyneodecanoate, and QPOND represents t-cumylperoxyneodecanoate. Represents Eat.

[0089]Evaluation method  (2) Graft ratio About 10 g of vinyl chloride resin (hereinafter referred to as W₁g)
5 in 100 ml of tetrahydrofuran (THF).
After stirring and mixing for 0 hour, the portion insoluble in THF was
Separated from the THF solution with a wire mesh of
It dried day and night. The weight of the obtained dried product is weighed (hereinafter referred to as W
2g) and chlorine content (hereinafter C%)
Quantified. From these results, the following formula (1)
Was used to calculate the graft ratio. Graft ratio (%) = [(C · W2 / 56.8) × 100] / [W1-W2 (1-C / 56.8)] (1)

(3) Impact resistance (%) The Charpy impact value was measured in accordance with JIS K 7111.
Specified. As a measurement sample, vinyl chloride graft copolymer
0.5 parts by weight of organotin-based stabilizer per 100 parts by weight of coalescing
Part, a resin composition containing 1.0 part by weight of a montanic acid-based lubricant
Roll kneaded at 200 ° C for 3 minutes.
Press molding for 3 minutes to make a 3 mm thick press plate
Was. The measurement was performed at room temperature. Note that impact resistance is required.
70 kwf · cm / cm ^Two 
It is preferable to have the above Charpy impact value.

(4) Weather Resistance The same press plate as the one prepared when measuring the Charpy impact value was used as a sample, and the weather resistance was evaluated using a super UV tester (manufactured by Iwasaki Electric Co., Ltd.). 8 specimens
In a black panel of 0 ± 2 ° C, UV illuminance 70m
UV irradiation at W / cm ² for 12 hours, rest for 8 hours, condensation 4
Irradiation treatment was performed for 10 cycles in a cycle of time. After treatment,
The Charpy impact value of the test piece was measured according to JIS K7111. The measurement was performed at 23 ° C. When the impact strength was 75% or more before the treatment, it was determined that the resin had sufficient weather resistance.

[0092]

[Table 1]

Comparative Examples 1 to 6 An acrylic copolymer was obtained in the same manner as in Example 1 except that the compounds having the compositions shown in Table 2 were used. The obtained acrylic copolymer was evaluated in the same manner as in Example 1, and the results are shown in Table 2. A vinyl chloride resin was obtained in the same manner as in Example 1 using the obtained acrylic copolymer. The obtained vinyl chloride resin was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 7 The acrylic copolymer obtained in Example 1 and a degree of polymerization of 100
No. 0 vinyl chloride resin was blended with the composition shown in Table 2 to obtain a vinyl chloride resin. The obtained vinyl chloride resin was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[0095]

[Table 2]

COMPARATIVE EXAMPLE 8 Except that a monomer having an organosiloxane as a main component shown in Table 3 was used as a core emulsifying monomer, and a monomer having a (meth) acrylate as a main component shown in Table 3 was used as a shell emulsifying monomer. A vinyl chloride resin was obtained in the same manner as in Example 1. The obtained vinyl chloride resin was evaluated in the same manner as in Example 1, and the results are shown in Table 3.

[0097]

[Table 3]

[0098]

As described above, the vinyl chloride resin of the present invention is excellent in impact resistance and weather resistance because it has the above-mentioned constitution. Further, since the method for producing a vinyl chloride resin of the present invention has the above-described configuration, it is possible to produce a vinyl chloride resin having excellent impact resistance and weather resistance.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J026 AA45 AA46 AA76 AB44 AC15 AC34 BA10 BA43 DA04 DB04 GA02

Claims (2)

[Claims] An acrylic copolymer obtained by graft polymerization of vinyl chloride is dispersed in a resin containing polyvinyl chloride as a main component, and the acrylic copolymer has a core-shell two-layer structure. A vinyl chloride resin,
The core part of the acrylic copolymer is composed of a copolymer having a glass transition temperature of −140 ° C. or more and less than −20 ° C. and containing poly (meth) acrylate as a main component, and the shell part of the acrylic copolymer is A vinyl chloride resin comprising a copolymer containing polyorganosiloxane as a main component, wherein the graft ratio of the vinyl chloride is 0.1 to 5% by weight. 2. The glass transition temperature of the homopolymer is -140.
A copolymer consisting of 100 parts by weight of a polymerizable monomer having a (meth) acrylate as a main component at a temperature of not lower than -20 ° C and 0.3 to 20 parts by weight of an organosiloxane having a radically polymerizable unsaturated double bond. 90% by weight, 10 to 70% by weight of a mixed organosiloxane comprising 100 parts by weight of an organosiloxane and 0.3 to 20 parts by weight of an organosiloxane having a radical polymerizable unsaturated double bond.
And after producing an acrylic copolymer by graft polymerization of a vinyl chloride resin obtained by graft-polymerizing a vinyl monomer containing vinyl chloride as a main component to the obtained acrylic copolymer. Production method.