JP2002249634A - Vinyl chloride resin composition for regenerated pipe and regenerated pipe made from vinyl chloride resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vinyl chloride resin composition suitable for a regenerated pipe excellent in mechanical strength, impact resistance and executability, and a regenerated vinyl chloride resin pipe using the same. SOLUTION: A conjugated vinyl chloride resin the average degree of polymerization of which ranges 400-2500 is composed by graft-copolymerizing 97-90 wt.% of vinyl chloride monomer or of vinyl chloride monomer and other copolymerizing monomers to 3-10 wt.% of an acrylic copolymer composed by copolymerizing a 100 pts.wt. acrylic monomer component containing 50 wt.% or more of an alkyl acrylate or methacrylate monomer of which the glass transition temperature of its homopolymer ranges -140 to -20 deg.C and 50 wt.% or less of other acrylic monomers with a 0.01-30 pts.wt. multifunctional monomer component. The vinyl chloride resin composition for regenerated pipe is composed by adding a 3-30 pts.wt. urethane elastomer which can be miscible with the conjugated vinyl chloride resin to 100 pts.wt. of this conjugated vinyl chloride resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vinyl chloride resin composition for a rehabilitation pipe and a vinyl chloride resin rehabilitation pipe using the vinyl chloride resin composition.

[0002]

2. Description of the Related Art In recent years, the number of aging pipes has been increasing. One of the methods for repairing such aging pipes is a vinyl chloride resin having excellent mechanical strength and chemical resistance. There is a method using a tube.

[0003] For example, Japanese Patent Publication No. Hei 6-508647 discloses a method of repairing a resin pipe by adding a thermoplastic elastomer that can be mixed with a vinyl chloride resin.
However, in the case of this method, it is necessary to add a large amount of a thermoplastic elastomer, an impact modifier, etc. in order to develop impact resistance sufficient to prevent breakage of the resin tube during transportation or construction. There is a problem that the mechanical strength of the obtained resin tube is insufficient.

[0004]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to combine excellent mechanical strength and impact resistance,
An object of the present invention is to provide a vinyl chloride resin composition for a rehabilitation pipe suitable for obtaining a rehabilitation pipe excellent in workability, and a vinyl chloride resin rehabilitation pipe using the vinyl chloride resin composition.

[0005]

Means for Solving the Problems A vinyl chloride resin composition for a rehabilitation pipe according to the invention of claim 1 (hereinafter referred to as "the present invention 1") (hereinafter simply referred to as "vinyl chloride resin composition"). ) Is the glass transition temperature (T
g) 100 parts by weight of an acrylic monomer component containing 50% by weight or more of an alkyl (meth) acrylate monomer having a temperature of -140 to -20 ° C and 50% by weight or less of another acrylic monomer, and a polyfunctional monomer component 0 .
Acrylic copolymer obtained by copolymerizing 01 to 30 parts by weight
10% by weight of a vinyl chloride monomer or 97 to 90% by weight of a vinyl chloride monomer and other copolymerizable monomer is graft-copolymerized, and 100 parts by weight of a composite vinyl chloride resin having an average degree of polymerization of 600 to 3000 is used. Urethane-based elastomer compatible with composite vinyl chloride-based resin 3 ~
It is characterized by adding 30 parts by weight. Here, (meth) acrylate means acrylate or methacrylate.

The vinyl chloride resin rehabilitation pipe (hereinafter simply abbreviated as “rehabilitation pipe”) according to the invention of claim 2 (hereinafter referred to as “invention 2”) is a vinyl chloride resin rehabilitation pipe of the invention 1 described above. It is made of a resin composition, and is inserted into an existing pipe,
It is characterized in that it is brought into close contact with the inner surface of the existing pipe by being heated.

[0007] The homopolymer contained in the acrylic monomer component used in the present invention 1 has a Tg of -140 to -2.
Examples of the alkyl (meth) acrylate monomer at 0 ° C include ethyl acrylate (-24 ° C), n-
Propyl acrylate (-37 ° C), n-butyl acrylate (-54 ° C), isobutyl acrylate (-24
° C), sec-butyl acrylate (-21 ° C), n-
Hexyl acrylate (-57 ° C), 2-ethylhexyl acrylate (-85 ° C), n-octyl acrylate (-85 ° C), n-octyl methacrylate (-25
C), isooctyl acrylate (-45 C), n-nonyl acrylate (-63 C), n-nonyl methacrylate (-35 C), isononyl acrylate (-85 C)
C), n-decyl acrylate (-70C), n-decyl methacrylate (-45C), lauryl methacrylate (-65C), and the like. These alkyl (meth) acrylate monomers may be used alone or in combination of two or more. The parentheses indicate the Tg of the homopolymer.

If the homopolymer of the above alkyl (meth) acrylate monomer has a Tg of less than -140 ° C., the mechanical strength of the resulting vinyl chloride resin composition and the rehabilitation pipe becomes insufficient, and conversely, the alkyl (meth) acrylate ) When the Tg of the homopolymer of the acrylate monomer exceeds -20 ° C, the resulting vinyl chloride resin composition and the impact resistance of the rehabilitation pipe become insufficient.

Other acrylic monomers that may be contained in the acrylic monomer component used in the present invention 1 include, for example, phenyl acrylate, 2-chloroethyl acrylate, phenylmethyl methacrylate,
And hydroxyethyl acrylate. These other acrylic monomers may be used alone or in combination of two or more.

The Tg of the homopolymer in the acrylic monomer component used in the present invention is -140 to -2.
When the content of the alkyl (meth) acrylate monomer at 0 ° C. is less than 50% by weight or the content of the other acrylic monomer exceeds 50% by weight, the obtained vinyl chloride resin composition and rehabilitation pipe The impact resistance of the rehabilitated pipe to the existing pipe becomes insufficient or the impact resistance becomes insufficient.

The polyfunctional monomer component used in the present invention 1 may be any as long as it can be copolymerized with the above acrylic monomer component. For example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane di (meth)
Polyfunctional (meth) acrylates such as acrylate and trimethylolpropane tri (meth) acrylate; polyfunctional allyl compounds such as diallyl phthalate, diallyl maleate and triallyl isocyanurate; and unsaturated compounds such as butadiene. These polyfunctional monomer components may be used alone or in combination of two or more.

The acrylic copolymer used in the present invention 1 is an acrylic copolymer obtained by copolymerizing 100 parts by weight of the acrylic monomer component and 0.01 to 30 parts by weight of the polyfunctional monomer component. It is a polymer. If the copolymerization amount of the polyfunctional monomer component is less than 0.01 parts by weight or more than 30 parts by weight with respect to 100 parts by weight of the acrylic monomer component, the acrylic copolymer sufficiently exhibits an elastomeric function. Otherwise, the impact resistance of the obtained vinyl chloride resin composition and the rehabilitated pipe becomes insufficient.

The acrylic copolymer can be obtained by, for example, an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, etc. Among them, the emulsion copolymer method is particularly preferred since the particle size of the copolymer is easily controlled. A polymerization method is preferably employed. The method of the emulsion polymerization may be a conventionally known method and, if necessary, within a range not hindering the achievement of the object of the present invention, for example, an emulsifying dispersant,
Emulsion polymerization may be performed by adding one or more of various additives such as a polymerization initiator, a pH adjuster, and an antioxidant.

Examples of the emulsifying dispersant include anionic surfactants, nonionic surfactants, partially saponified polyvinyl alcohol, cellulose dispersants, and gelatin. Among them, anionic surfactants are preferred. Used. Examples of commercially available anionic surfactants include, for example, polyoxyethylene nonyl phenyl ether sulfate (trade name “HITENOL N-08”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). These emulsifying and dispersing agents may be used alone or in combination of two or more.

Examples of the polymerization initiator include water-soluble initiators such as ammonium persulfate, potassium persulfate and hydrogen peroxide; benzoyl peroxide, lauroyl peroxide, t-butylperoxydecanoate, α-cumylperoxyneo. Organic peroxides such as decanate; azo initiators such as azobisisobutyronitrile; These polymerization initiators may be used alone or in combination of two or more.

Specific examples of the emulsion polymerization method include a batch polymerization method, a monomer dropping method, and an emulsion dropping method. In the batch polymerization method, pure water, an emulsifying dispersant, a polymerization initiator, and an acrylic mixed monomer (the acrylic monomer component + a polyfunctional monomer component) are charged all at once into a jacketed polymerization reactor, and the mixture is placed in a nitrogen stream. In this method, the mixture is sufficiently emulsified by stirring under pressure, and then the temperature inside the polymerization reactor is raised by a jacket to start the polymerization reaction. or,
The monomer dropping method uses pure water in a jacketed polymerization reactor,
This is a method in which an emulsifying dispersant and a polymerization initiator are charged, the temperature inside the polymerization reactor is raised under a nitrogen stream, and then the above-mentioned acrylic mixed monomer is dropped in a fixed amount to start a polymerization reaction. Further, in the emulsion dropping method, the above-mentioned mixed monomer, emulsifying dispersant, and pure water are stirred to prepare an emulsifying monomer liquid in advance,
Next, pure water and a polymerization initiator are charged into a polymerization reactor with a jacket, and after the temperature in the polymerization reactor is increased under a nitrogen stream, the polymerization reaction is started by dropping the emulsified monomer liquid by a predetermined amount. is there.

The structure and form of the acrylic copolymer (acrylic resin) thus obtained are not particularly limited, but the stability of the resin particles can be improved, and the mechanical properties of the vinyl chloride resin composition and the rehabilitation pipe can be improved. For example, those having a so-called core-shell structure in which the monomer composition and the cross-linked structure are different between the surface layer portion and the inside of the resin particle are preferable because the mechanical strength can be improved.

The core-shell structure can be formed, for example, by adding a polymerization initiator to an emulsified monomer liquid previously prepared from the above-mentioned acrylic mixed monomer, emulsifying dispersant, and pure water, which constitutes the core portion, and conducting polymerization reaction. First, the resin particles of the core portion are formed. Then, a method of adding the above-mentioned acrylic mixed monomer, an emulsifying dispersant, and an emulsifying monomer liquid prepared in advance from pure water, which constitutes the shell portion, and graft-copolymerizing the above-mentioned core portion may be used.

In the above method, the graft copolymerization of the shell with respect to the core may be carried out continuously in the same polymerization step as the polymerization of the core. The ratio of core and shell is
It can be freely adjusted by adjusting the ratio of the acrylic mixed monomer forming the core portion and the acrylic mixed monomer forming the shell portion. Further, in order to form a three-dimensional cross-linked structure in the shell portion, the polyfunctional monomer component may be used only in the shell portion, or may be used by being biased in the shell portion. Also in this case, the amount of the polyfunctional monomer component used is 0.01 to 30 parts by weight of the polyfunctional monomer component with respect to 100 parts by weight of the acrylic monomer component for the entire acrylic copolymer.

In the acrylic copolymer particles obtained by such a method, the shell part three-dimensionally covers the surface of the core part, and the resin constituting the shell part and the resin constituting the core part are partially formed. They are covalently bonded and the shell forms a three-dimensional crosslinked structure.

The vinyl chloride resin used in the present invention 1 is obtained by grafting a vinyl chloride monomer or 97 to 90% by weight of a vinyl chloride monomer and another copolymerizable monomer to 3 to 10% by weight of the acrylic copolymer. It is a resin having an average degree of polymerization of 400 to 2500 obtained by copolymerization.

The other copolymerizable monomer that may be used in combination with the vinyl chloride monomer may be any monomer that can be copolymerized with the vinyl chloride monomer. Examples thereof include α-olefins such as ethylene, propylene, and butylene; and propionic acid. Vinyl esters such as vinyl; vinyl ethers such as ethyl vinyl ether and butyl vinyl ether; (meth) acrylates such as methyl (meth) acrylate, butyl (meth) acrylate, and hydroxyethyl (meth) acrylate; styrene, α-methylstyrene, and the like Aromatic vinyls; vinyl fluoride, vinylidene fluoride,
Vinyl halides such as vinylidene chloride; and N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide. These other copolymerizable monomers may be used alone or in combination of two or more.

When the vinyl chloride monomer is used in combination with the above-mentioned other copolymerizable monomer, the amount of the other copolymerizable monomer to be used is appropriately determined according to the performance and purpose to be imparted to the vinyl chloride resin composition and the rehabilitation pipe. The setting is not particularly limited, but is preferably 20% by weight or less in a vinyl chloride-based mixed monomer composed of a vinyl chloride monomer and another copolymerizable monomer. If the amount of the other copolymerizable monomer exceeds 20% by weight of the vinyl chloride-based mixed monomer, the intrinsic properties of the vinyl chloride-based resin may not be obtained.

In the vinyl chloride resin used in the present invention 1, the content of the acrylic copolymer is less than 3% by weight, or the amount of the vinyl chloride monomer or the vinyl chloride-based mixed monomer is 97% by weight. If it exceeds 3, the impact resistance of the obtained vinyl chloride resin composition and rehabilitating pipe becomes insufficient, and conversely, the content of the acrylic copolymer exceeds 10% by weight, or the vinyl chloride monomer or vinyl chloride If the amount of the monomer is less than 90% by weight, it is not possible to obtain the intrinsic properties of the vinyl chloride resin.

On the other hand, if the average degree of polymerization of the vinyl chloride resin is less than 400, the mechanical strength of the obtained vinyl chloride resin composition and the rehabilitation pipe become insufficient, and conversely, the average If the degree of polymerization exceeds 2500, the moldability of the resulting vinyl chloride resin composition will be impaired.
The average degree of polymerization refers to a resin obtained by dissolving a vinyl chloride resin in tetrahydrofuran (THF), removing insoluble components by filtration, and drying and removing THF in the filtrate as a sample. 6721 means the average degree of polymerization measured in accordance with "Test Method for Vinyl Chloride Resin".

The graft copolymerization method between the acrylic copolymer and the vinyl chloride monomer or the vinyl chloride-based mixed monomer may be a conventionally known method, for example, a suspension polymerization method, an emulsion polymerization method, a solution polymerization method and the like. In general, a method in which an acrylic copolymer in an emulsified state (emulsion state) is suspension-polymerized with a vinyl chloride monomer or a vinyl chloride-based mixed monomer is used. In the suspension polymerization method, the emulsifying dispersant, the polymerization initiator, and the like are used.

As a specific method of the suspension polymerization method, for example, pure water, an emulsifying dispersant, a polymerization initiator, and an acrylic copolymer emulsion are charged into a polymerization reactor equipped with a stirrer and a temperature controller. After the air in the polymerization reactor is eliminated by a vacuum pump, a vinyl chloride monomer or a vinyl chloride-based mixed monomer is introduced into the polymerization reactor. Next, the temperature of the polymerization reactor is raised to start the polymerization reaction at a desired polymerization temperature. After completion of the polymerization reaction, the residual monomer is discharged out of the polymerization reactor to obtain a slurry of the vinyl chloride resin, and then subjected to steps such as dehydration by a dehydrator and drying by a drier to obtain a desired composite vinyl chloride resin. A resin can be obtained.

The vinyl chloride resin composition according to the first aspect of the present invention comprises a urethane elastomer 3 to 3 which is compatible with the vinyl chloride resin based on 100 parts by weight of the vinyl chloride resin.
30 parts by weight are added.

To the urethane-based elastomer, a thermoplastic elastomer compatible with the vinyl chloride-based resin may be added. For example, acrylonitrile-butadiene copolymer (NBR), ethylene-vinyl acetate copolymer ( EVA), vinyl chloride-based thermoplastic elastomers such as ethylene-vinyl acetate-carbon monoxide copolymer (EVACO), vinyl chloride-vinyl acetate copolymer and vinyl chloride-vinylidene chloride copolymer, and styrene-based thermoplastic elastomers. Examples include olefin-based thermoplastic elastomers, polyester-based thermoplastic elastomers, and polyamide-based thermoplastic elastomers. These thermoplastic elastomers may be used alone or in combination of two or more.

If the amount of the urethane-based elastomer is less than 3 parts by weight based on 100 parts by weight of the vinyl chloride-based resin, a rehabilitation pipe made of the obtained vinyl chloride-based resin composition is inserted into an existing pipe and heated. If the workability at the time of closely adhering to the existing pipe is impaired, and if the amount of the urethane-based elastomer added to 100 parts by weight of the vinyl chloride-based resin exceeds 30 parts by weight, the obtained vinyl chloride-based resin composition and the machine for the rehabilitation pipe are used. The target strength becomes insufficient.

The vinyl chloride resin composition of the present invention 1 comprises:
If necessary within a range that does not impair the achievement of the object of the present invention, in addition to the essential components, a composite vinyl chloride resin and a thermoplastic elastomer, a filler, a pigment, a lubricant, a processing aid, a stabilizer, a stabilization aid, One or more of various additives such as a light stabilizer, an ultraviolet absorber, an antioxidant (antiaging agent), an antistatic agent, and a flame retardant may be added. The method and order of addition of these additives are not particularly limited, and may be any method and any order.

Examples of the filler include inorganic fillers such as calcium carbonate, talc, clay and silica. These fillers may be used alone or 2
More than one type may be used in combination.

Examples of the pigment include organic pigments such as azo type, phthalocyanine type, sulene type and dye lake type; and inorganic pigments such as molybdenum chromate type and ferrocyanide type. These pigments may be used alone or in combination of two or more.

Examples of the lubricant include fatty acids such as stearic acid; fatty acid esters; olefin waxes. These lubricants may be used alone or in combination of two or more.

Examples of the processing aid include homopolymers or copolymers of (meth) acrylate monomers such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) acrylate; And copolymers of a vinyl monomer and a vinyl monomer such as styrene, vinyl toluene and acrylonitrile. These processing aids may be used alone or in combination of two or more.

Examples of the stabilizer include organic tin stabilizers such as dibutyltin malate and dioctyltin laurate; lead white, basic lead sulfite, dibasic lead sulfite, tribasic lead sulfate, dibasic phosphorous acid Lead stabilizers such as lead, silica gel coprecipitated lead silicate, lead stearate, lead benzoate, dibasic lead stearate, lead naphthenate; metal soap based stabilizers such as calcium stearate, barium stearate and zinc stearate Agents; inorganic stabilizers such as hydrotalcite and zeolite; These stabilizers may be used alone or in combination of two or more.

Examples of the stabilizing aid include epoxidized soybean oil, epoxidized linseed oil, and phosphate esters. These stabilizing aids may be used alone or in combination of two or more.

Examples of the light stabilizer include hindered amine light stabilizers. These light stabilizers are
They may be used alone or in combination of two or more.

Examples of the ultraviolet absorber include salicylic acid ester, benzophenone, benzotriazole and cyanoacrylate ultraviolet absorbers. These ultraviolet absorbers may be used alone or in combination of two or more.

Next, the rehabilitating pipe according to the second aspect of the present invention is made of the above-mentioned vinyl chloride resin composition of the first aspect of the present invention, and is inserted into the existing pipe and heated to adhere to the inner surface of the existing pipe. It is characterized by doing.

The rehabilitating pipe is used in the present invention 1 using an extruder.
The vinyl chloride resin composition is melt-kneaded, extruded, and shaped into a tubular body having a desired cross-sectional shape. The cross-sectional shape of the rehabilitating pipe is not particularly limited as long as it can be inserted into the existing pipe to be rehabilitated (repaired) and can be brought into close contact with the inner surface of the existing pipe by heating.

(Function) The vinyl chloride resin composition of the present invention is obtained by adding a vinyl chloride monomer to a specific amount of an acrylic copolymer obtained by copolymerizing a specific amount of a specific acrylic monomer component and a specific amount of a polyfunctional monomer component. Or, a specific amount of a vinyl chloride-based mixed monomer is graft-copolymerized, and, for a specific amount of a vinyl chloride-based resin having a specific average degree of polymerization,
Since a specific amount of the urethane-based elastomer compatible with the above-mentioned composite vinyl chloride-based resin is added, the mechanical strength and impact resistance are expressed in an excellent balance, and the workability when the pipe is rehabilitated is improved. Is also excellent.

Further, since the rehabilitating pipe of the present invention is made of the vinyl chloride resin composition of the present invention, it has both excellent mechanical strength and impact resistance, and also has excellent workability. Inserted into the existing pipe to be rehabilitated (repaired)
By being heated, it can easily adhere to the inner surface of the existing pipe.

[0044]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 (Preparation of Acrylic Copolymer) As an acrylic monomer component, n-butyl acrylate (Tg of a homopolymer:-
2.36 kg of an acrylic mixed monomer containing 95% by weight of 95% by weight and 5% by weight of trimethylolpropane triacrylate as a polyfunctional monomer component, and a trade name of "HITENOL N-08" (first An emulsified monomer solution comprising 50 g of a 10% aqueous solution of Kogyo Seiyaku Co., Ltd.) and 1.5 kg of pure water was prepared in advance.

4 kg of pure water and 24 g of a 10% aqueous solution of ammonium persulfate as a polymerization initiator were charged into a 10 L polymerization reactor equipped with a stirrer and a temperature controller, and the inside of the polymerization vessel was replaced with nitrogen gas. 75 ° C inside the polymerization reactor
The temperature rose. Next, the above-prepared emulsified monomer liquid was dropped into the polymerization reactor at a constant rate. The dropping of the entire amount of the emulsified monomer liquid was completed in 3 hours, and then stirring was continued for 1 hour. Then, the polymerization reaction was terminated, and the solid content was reduced to 30%.
Was prepared.

(Preparation of Vinyl Chloride Resin) A 15 L polymerization reactor equipped with a stirrer and a temperature controller was charged with 7.5 k of pure water.
g, 0.5 kg (solid content: 0.15 kg) of the acrylic copolymer emulsion obtained above, 3% of partially saponified polyvinyl alcohol (trade name "Kuraray Povar L-8", manufactured by Kuraray) as an emulsifying dispersant 330 g of an aqueous solution, 1.1 g of each of t-butylperoxydecanoate and α-cumylperoxyneodecanate as a polymerization initiator were charged, and the air in the polymerization reactor was discharged by a vacuum pump. 3.0 kg were added. Next, the temperature in the polymerization reactor was raised to 50 ° C. to start the graft polymerization reaction. After confirming the completion of the graft polymerization reaction by lowering the pressure in the polymerization reactor, the unreacted vinyl chloride monomer was discharged to produce a vinyl chloride resin. The amount of the vinyl chloride resin in the obtained vinyl chloride resin was 94% by weight.
And the content of the acrylic copolymer was 6% by weight. The average degree of polymerization of the obtained vinyl chloride resin was determined by JI
When measured in accordance with SK-6721, the average degree of polymerization was 1,400.

(Preparation of Vinyl Chloride Resin Composition and Rehabilitation Tube) In a Henschel mixer (manufactured by Kawada Industries) having an internal volume of 100 L, 100 parts by weight of the vinyl chloride resin obtained above, and a urethane elastomer (commercially available) Name "T-52
75N ", manufactured by Dainippon Ink and Chemicals, Inc., 12 parts by weight, an organotin-based stabilizer as a stabilizer (trade name" ONZ-142 ")
F ", manufactured by Sankyoki Co., Ltd.) 2 parts by weight, polyethylene wax-based lubricant (trade name" Hiwax220MP ")
0.5 parts by weight of stearic acid (trade name "S-30", manufactured by Kao Corporation) as a lubricant.
5 parts by weight and trade name "METABLEN P50" as a processing aid
1A "(manufactured by Mitsubishi Rayon Co., Ltd.) was charged in an amount of 3 parts by weight, and uniformly stirred and mixed to prepare a vinyl chloride resin composition.

The above-obtained vinyl chloride resin composition was supplied to a biaxially different-direction rotary extruder (trade name “SLM-50”, manufactured by Nagata Seisakusho) having a screw diameter of 50 mm and an outer diameter of 5 mm.
A vinyl chloride resin tube having a diameter of 0 mm and an inner diameter of mm was obtained. The obtained molded body was placed in a gear oven heated to 80 ° C.
After standing for 0 minutes, the cross section of the rehabilitated pipe is made into a four-fold shape, and the temperature of the molded body is kept at 20 while maintaining this shape.
After cooling to ℃, a rehabilitated tube was prepared.

[Evaluation] The rehabilitated pipe obtained above was evaluated for flexural modulus, impact resistance and workability by the following methods.
The results were as shown in Table 1.

(Flexural Modulus) The flexural modulus of the rehabilitated pipe was measured in accordance with JIS K-7203 “Bending test method for hard plastics”. The measurement was performed in an atmosphere at 20 ° C.

(Impact resistance) In accordance with JIS K-7111 "Charpy impact test method for hard plastic",
The Charpy impact value of the rehabilitated tube was measured using a notched (notched) test piece. The measurement was performed in an atmosphere at 23 ° C.

(Workability) A rehabilitating pipe is inserted into a steel pipe having an inner diameter of 50 mm, and one end of the rehabilitating pipe is inserted into the rehabilitating pipe by 90 mm.
C. hot air was blown for 10 minutes to bring the rehabilitation pipe into close contact with the inner surface of the steel pipe. Next, after cooling by blowing air at 20 ° C. for 30 minutes, the adhesion between the steel pipe and the rehabilitation pipe was visually observed, and the workability was evaluated according to the following criteria. ○ ‥‥ The rehabilitation pipe was in full contact with the steel pipe × ‥‥ The rehabilitation pipe was not in close or partial contact with the steel pipe

Example 2 The same procedure as in Example 1 was carried out except that the vinyl chloride resin was used in which the amount of vinyl chloride was 92% by weight and the content of the acrylic copolymer was 8% by weight. , A vinyl chloride-based resin composition and a rehabilitation pipe were produced.

Example 3 A vinyl chloride resin composition and a rehabilitation were performed in the same manner as in Example 1 except that a vinyl chloride resin having an average degree of polymerization of 1000 measured according to JIS K-6721 was used. A tube was made.

Example 4 A vinyl chloride resin composition and a rehabilitation pipe were prepared in the same manner as in Example 1 except that the amount of the urethane elastomer was changed to 15 parts by weight in the preparation of the vinyl chloride resin composition. Was prepared.

Comparative Example 1 A vinyl chloride resin having a vinyl chloride content of 98% by weight and an acrylic copolymer content of 2% by weight was used in the same manner as in Example 1 except that a vinyl chloride resin was used. , A vinyl chloride-based resin composition and a rehabilitation pipe were produced.

Comparative Example 2 A vinyl chloride resin composition and a rehabilitating tube were prepared in the same manner as in Example 1 except that no thermoplastic elastomer was added in the preparation of the vinyl chloride resin composition.

Comparative Example 3 A vinyl chloride resin composition and a rehabilitation pipe were prepared in the same manner as in Example 1 except that the amount of the urethane elastomer was changed to 40 parts in the preparation of the vinyl chloride resin composition. Was prepared.

Comparative Example 4 Without using a vinyl chloride-based resin,
The average degree of polymerization measured according to IS K-6721 is 1
A vinyl chloride resin composition and a rehabilitating tube were produced in the same manner as in Example 1 except that 400 vinyl chloride homopolymers were used.

The rehabilitated tubes obtained in Examples 2 to 4 and Comparative Examples 1 to 4 were evaluated in the same manner as in Example 1. The results were as shown in Table 1.

[0062]

[Table 1]

As is clear from Table 1, Examples 1 to 4 prepared using the vinyl chloride resin composition of the present invention.
The rehabilitated pipe had excellent flexural modulus (mechanical strength), impact resistance and workability.

On the other hand, the amount of vinyl chloride was 98% by weight.
The rehabilitating tube of Comparative Example 1 made of a vinyl chloride resin composition prepared using the vinyl chloride resin, and without using the vinyl chloride resin, instead using a vinyl chloride homopolymer The rehabilitated pipe of Comparative Example 4 made of the produced vinyl chloride resin composition had extremely poor impact resistance.

The rehabilitating pipe of Comparative Example 2 comprising a vinyl chloride resin composition in which no thermoplastic elastomer was added to the vinyl chloride resin had poor workability. further,
The rehabilitated pipe of Comparative Example 3 comprising the vinyl chloride resin composition in which the urethane elastomer was added in an amount of 40 parts by weight based on 100 parts by weight of the composite vinyl chloride resin had a low flexural modulus (mechanical strength).

[0066]

As described above, the vinyl chloride resin composition of the present invention exhibits excellent mechanical strength and impact resistance and also has excellent workability when used as a rehabilitated pipe. ,
It is suitably used as a resin for producing rehabilitating tubes. Further, since the rehabilitation pipe of the present invention is made of the vinyl chloride resin composition of the present invention, it has excellent mechanical strength and impact resistance at a high level, and has excellent workability. It is suitably used for pipe rehabilitation (repair).

Continued on the front page F term (reference) 3H111 AA01 BA15 BA34 DA26 DB27 EA04 4J002 BN121 CK022 GL00 4J026 AA45 AA46 AA47 AC33 AC34 BA10 BB01 BB02 DA03 DA04 DA05 DA12 DA13 DB03 DB04 GA09

Claims (2)

[Claims] The glass transition temperature of the homopolymer is -140.
50% by weight or more of an alkyl (meth) acrylate monomer having a temperature of -20 ° C and other acrylic monomers 50
Acrylic monomer component 10 containing at most 10% by weight
0 to 10 parts by weight of an acrylic copolymer obtained by copolymerizing 0 parts by weight and 0.01 to 30 parts by weight of a polyfunctional monomer component,
With respect to 100 parts by weight of a composite vinyl chloride resin having an average degree of polymerization of 400 to 2500 obtained by graft copolymerizing a vinyl chloride monomer or 97 to 90% by weight of a vinyl chloride monomer and other copolymerizable monomers, the composite vinyl chloride resin A vinyl chloride resin composition for rehabilitating pipes, comprising 3 to 30 parts by weight of a urethane elastomer which is compatible with water. 2. A chloride made of the vinyl chloride resin composition for rehabilitating pipes according to claim 1, which is inserted into an existing pipe and heated so as to adhere to the inner surface of the existing pipe. Vinyl resin rehabilitation pipe.