JP2002156569A - Vinyl chloride resin tube for lining protective tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vinyl chloride resin tube for lining a protective tube having both superior mechanical strength and impact resistance and excellent also in suitability to application. SOLUTION: The vinyl chloride resin tube comprises a vinyl chloride resin composition prepared by adding 3-30 pts.wt. thermoplastic elastomer (F) to 100 pts.wt. composite vinyl chloride resin (E) obtained by copolymerizing 100 pts.wt. acrylic monomer components (A) including >=50 wt.% alkyl(meth)acrylate monomer and <50 wt.% another acrylic monomer with a polyfunctional monomer component (B) and graft-copolymerizing 3-10 wt.% of the resulting acrylic copolymer (C) with 97-90 wt.% vinyl chloride monomer or vinyl chloride monomer and another copolymerizable monomer (D). The vinyl chloride resin tube sticks fast to the internal surface of an existing tube when inserted into the existing tube and heated.

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 tube for lining a protective tube for rehabilitating a protective tube for protecting a communication wiring or the like laid inside.

[0002]

2. Description of the Related Art When laying communication wiring such as an optical fiber, it is widely practiced to lay communication wiring in a protective tube to protect the communication wiring. If the protective tube is used for many years, the material may deteriorate due to corrosion or the like, and may be damaged by an external load or impact. If a damaged portion occurs in the protective tube, it is easily broken by the inflow of groundwater or an external load, and it becomes difficult to fulfill the role of the protective tube, causing accidents such as disconnection or short circuit of communication wiring.

[0003] As a resin tube for rehabilitating a communication line protection tube damaged in this way, for example, Japanese Patent Application Laid-Open No. 8-157608 discloses a vinyl chloride resin tube in which an acrylic modifier is mixed with a vinyl chloride resin. I have. However, this method is insufficient in workability, and the impact resistance is not sufficient.

[0004]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a vinyl chloride resin tube for a protective tube lining which has both excellent mechanical strength and impact resistance and is excellent in workability. With the goal.

[0005]

SUMMARY OF THE INVENTION A vinyl chloride resin tube for lining a protective tube of the present invention (hereinafter abbreviated as "rehabilitating tube").
Means that the glass transition temperature of the homopolymer is -140 to -20 ° C.
100 parts by weight of an acrylic monomer component (A) containing at least 50% by weight of an alkyl (meth) acrylate monomer and less than 50% by weight of another acrylic monomer, and 0.01 to 0.01% of a polyfunctional monomer component (B). Acrylic copolymer (C) copolymerized with 30 parts by weight was graft copolymerized with 3 to 10% by weight of vinyl chloride monomer or 97 to 90% by weight of vinyl chloride monomer and other copolymerizable monomer (D). An acrylonitrile-butadiene copolymer, an ethylene-vinyl acetate copolymer, and an ethylene-vinyl acetate-carbon monoxide copolymer are used for 100 parts by weight of the composite vinyl chloride resin (E) having an average degree of polymerization of 400 to 2500. Vinyl chloride containing 3 to 30 parts by weight of a thermoplastic elastomer (F) containing one or more selected from the group Made from the system resin composition, and is inserted into the existing pipe, and is characterized in that the close contact with the inner surface of the existing pipe by heating.

[0006] The homopolymer contained in the acrylic monomer component (A) used in the present invention has a Tg of -140 to
Examples of the alkyl (meth) acrylate monomer at −20 ° 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 (-8
5 ° C.), n-decyl acrylate (−70 ° C.), n-decyl methacrylate (−45 ° C.), lauryl methacrylate (−65 ° C.) 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 obtained 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 impact resistance of the obtained rehabilitated tube becomes insufficient.

Other acrylic monomers contained in the acrylic monomer component (A) used in the present invention include, for example, phenyl acrylate, 2-chloroethyl acrylate, phenylmethyl methacrylate, hydroxyethyl acrylate and the like. No. These other acrylic monomers may be used alone or in combination of two or more.

The homopolymer in the acrylic monomer component (A) used in the present invention has a Tg of from -140 to
When the content of the alkyl (meth) acrylate monomer at −20 ° C. is less than 50% by weight, or when the content of the other acrylic monomer is 50% by weight or more,
The impact resistance of the obtained rehabilitation pipe becomes insufficient, or the adhesion of the rehabilitation pipe to the existing pipe becomes insufficient.

The polyfunctional monomer component (B) used in the present invention may be any copolymerizable with the acrylic monomer component (A). Examples thereof include ethylene glycol di (meth) acrylate and diethylene glycol di (meth) acrylate. Polyfunctional (meth) acrylates such as (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane di (meth) 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 (B) may be used alone or in combination of two or more.

The acrylic copolymer (C) used in the present invention comprises 100 parts by weight of the acrylic monomer component (A) and 0.01 to 30 of the polyfunctional monomer component (B).
It is obtained by copolymerization with parts by weight. If the copolymerization amount of the polyfunctional monomer component (B) 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 (A), the acrylic copolymer (C) does not sufficiently exhibit an elastomeric function, and the resulting rehabilitated pipe has insufficient impact resistance.

The acrylic copolymer (C) can be obtained, for example, by an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, etc., and among them, it is easy to control the particle size of the copolymer. Therefore, an emulsion 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, various additives such as an emulsifying dispersant, a polymerization initiator, a pH adjuster, and an antioxidant Emulsion polymerization may be performed by adding one or more of the above.

Examples of the emulsifying and dispersing agent 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 into a jacketed polymerization reactor at a time, and the mixture is placed in a nitrogen stream. This is a method in which the mixture is sufficiently emulsified by stirring under pressure and then the temperature inside the polymerization reactor is increased 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, and the inside of the polymerization reactor is heated 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 jacketed polymerization reactor, and the temperature of the polymerization reactor is increased under a nitrogen stream. is there.

The structure and form of the acrylic copolymer (C) thus obtained are not particularly limited.
Since the stability of the resin particles can be improved and the mechanical strength of the vinyl chloride resin composition and the rehabilitation pipe can be improved, for example, a so-called core-shell structure in which the monomer composition and the crosslinked structure are different between the surface layer portion and the inside of the resin particles. Are preferred.

The above-mentioned core-shell structure can be formed, for example, by adding a polymerization initiator to an emulsion monomer solution prepared in advance from the above-mentioned acrylic mixed monomer, an emulsifying dispersant, and pure water, which constitutes the core portion, to carry out a 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 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 (B) 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 (B) to be used is 0.01 to 30 parts by weight with respect to 100 parts by weight of the acrylic monomer component (A) for the entire acrylic copolymer (C). You.

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

The composite vinyl chloride resin (E) used in the present invention is composed of a vinyl chloride monomer or a vinyl chloride monomer and another copolymerizable monomer (3 to 10% by weight) based on the acrylic copolymer (C). D) 97-90% by weight
Obtained by graft copolymerization, the average degree of polymerization is 400 to
2500 resins.

The other copolymerizable monomer (D) which may be used in combination with the vinyl chloride monomer may be any monomer copolymerizable with the vinyl chloride monomer.
Α-olefins such as ethylene, propylene and butylene;
Vinyl esters such as vinyl propionate; 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-methyl Aromatic vinyls such as styrene; vinyl halides such as vinyl fluoride, vinylidene fluoride and vinylidene chloride; N-vinylmaleimides such as N-phenylmaleimide and N-cyclohexylmaleimide
-Substituted maleimides and the like. The other copolymerizable monomers (D) may be used alone or in combination of two or more.

When the vinyl chloride monomer and the above-mentioned other copolymerizable monomer (D) are used in combination, the amount of the other copolymerizable monomer (D) to be used is appropriately set according to the performance and purpose to be imparted to the rehabilitation tube. The amount 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 (D). When the amount of the other copolymerizable monomer (D) used 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 composite vinyl chloride resin (E) used in the present invention, the content of the acrylic copolymer (C) is less than 3% by weight, or the content of the vinyl chloride monomer or the above-mentioned vinyl chloride-based mixed monomer is less than 3% by weight. If the amount used exceeds 97% by weight, the impact resistance of the obtained rehabilitated pipe becomes insufficient, and conversely, the content of the acrylic copolymer (C) exceeds 10% by weight, or the vinyl chloride monomer or vinyl chloride is used. If the amount of the system-mixed monomer is less than 90% by weight, the inherent characteristics of the vinyl chloride resin cannot be obtained.

If the average degree of polymerization of the composite vinyl chloride resin (E) is less than 400, the mechanical strength of the obtained rehabilitating pipe becomes insufficient, and conversely, the average of the composite vinyl chloride resin (E) becomes insufficient. 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 composite vinyl chloride-based resin in tetrahydrofuran (THF), removing insoluble components by filtration, and drying and removing THF in the filtrate as a sample. It means the average degree of polymerization measured in accordance with K-6721 "Testing method for vinyl chloride resin".

The graft copolymerization method of the acrylic copolymer (C) with the vinyl chloride monomer or the vinyl chloride-based mixed monomer may be a conventionally known method.
Examples include a suspension polymerization method, an emulsion polymerization method, and a solution polymerization method. Generally, an acrylic copolymer (C) in an emulsified state (emulsion state) is mixed with a vinyl chloride monomer or a vinyl chloride-based mixed monomer. A method of suspension polymerization 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 remaining monomer is discharged out of the polymerization reactor to obtain a slurry of the composite vinyl chloride-based resin, and then subjected to steps such as dehydration by a dehydrator and drying by a dryer, thereby obtaining a desired composite vinyl chloride. The system resin (E) can be obtained.

The vinyl chloride resin composition according to the present invention comprises:
For 100 parts by weight of the composite vinyl chloride resin (E),
Acrylonitrile-butadiene copolymer (hereinafter referred to as “NB
R ". ), Ethylene-vinyl acetate copolymer (hereinafter abbreviated as “EVA”), and ethylene-vinyl acetate-carbon monoxide copolymer (hereinafter abbreviated as “EVACO”). Alternatively, by adding 3 to 30 parts by weight of the thermoplastic elastomer (F) containing two or more kinds, the balance between the mechanical strength and the impact resistance of the obtained rehabilitated pipe becomes more excellent,
The workability when the rehabilitation pipe is inserted into the existing pipe and heated and brought into close contact with the inner surface of the existing pipe becomes more excellent.

The thermoplastic elastomer (F) is added in an amount of 3 parts by weight per 100 parts by weight of the composite vinyl chloride resin (E).
If the amount is less than 10 parts by weight, the workability of inserting the obtained rehabilitated pipe into the existing pipe and heating it to make it adhere to the existing pipe is impaired. If the amount of the plastic elastomer (F) exceeds 30 parts by weight, the mechanical strength of the rehabilitated pipe obtained will be insufficient.

The vinyl chloride resin composition of the present invention may contain, if necessary, components other than the composite vinyl chloride resin (E) and the thermoplastic elastomer (F), which are essential components, as long as the object of the present invention is not hindered. And various additives such as fillers, pigments, lubricants, processing aids, stabilizers, stabilizing aids, light stabilizers, ultraviolet absorbers, antioxidants (antiaging agents), antistatic agents, flame retardants, etc. One or more kinds may be added. The method and order of adding these additives are not particularly limited, and may be any method or any order.

Examples of the filler include inorganic fillers such as calcium carbonate, talc, clay and silica. These fillers may be used alone or in combination of two or more.

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

Examples of the ultraviolet absorber include salicylate-based, benzophenone-based, benzotriazole-based, and cyanoacrylate-based ultraviolet absorbers. These ultraviolet absorbers may be used alone or in combination of two or more.

Next, the rehabilitation pipe of the present invention is made of the above-mentioned vinyl chloride 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.

The rehabilitated pipe is melted and kneaded with the vinyl chloride resin composition according to the present invention using an extruder, formed into a tubular shape using an extruder and a tube molding die, and then formed into a desired cross section. It is produced by shaping into a tubular body. 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.

[0040]

The rehabilitating pipe of the present invention has a specific amount of an acrylic copolymer (C) obtained by copolymerizing a specific amount of a specific acrylic monomer component (A) with a specific amount of a polyfunctional monomer component (B). Specific amount of composite vinyl chloride resin (E) obtained by graft copolymerizing a specific amount of vinyl chloride monomer or vinyl chloride-based mixed monomer and other copolymerizable monomer (D) and having a specific average degree of polymerization NBR, EVA
And a vinyl chloride-based composition using a thermoplastic elastomer (F) containing one or more selected from the group consisting of EVACO and EVACO, so that it has both excellent mechanical strength and impact resistance. It is also excellent in workability, and can be easily brought into close contact with the inner surface of the existing pipe by being inserted into the existing pipe to be rehabilitated (repaired) and heated.

[0041]

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. In the examples, “parts” means “parts by weight”, and “%” means “% by weight”.

Example 1 (1) Preparation of Acrylic Copolymer (C) 95% of n-butyl acrylate (Tg of homopolymer: -54 ° C.) as an acrylic monomer component and a polyfunctional monomer component 2.3 acrylic mixed monomer containing 5% trimethylolpropane triacrylate
6 kg, trade name "HITENOL N-0" as an emulsifying dispersant
An emulsified monomer solution comprising 50 g of a 10% aqueous solution of 8 "(Daiichi 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 polymerization reactor (with an internal volume of 10 liters) equipped with a stirrer and a temperature controller, and the inside of the polymerization vessel was replaced with nitrogen gas. Thereafter, the temperature inside the polymerization reactor was raised to 75 ° C. with stirring. Next, the above-prepared emulsified monomer liquid was dropped at a constant dropping rate into the polymerization reactor after the temperature was raised. The dropping of the entire amount of the emulsified monomer liquid was completed in 3 hours, and thereafter, stirring was continued for 1 hour. Then, the polymerization reaction was terminated, and an acrylic copolymer emulsion having a solid content of 30% was prepared.

(2) Preparation of Composite Vinyl Chloride Resin (E) A polymerization reactor (with an internal volume of 15
Liter), 7.5 kg of pure water, 0.5 kg of the acrylic copolymer emulsion obtained above (solid content 0.1%).
5 kg), partially saponified polyvinyl alcohol as an emulsifying dispersant (trade name "Kuraray Povar L-8", manufactured by Kuraray Co., Ltd.)
Of a 3% aqueous solution of the above, 1.1 g of t-butylperoxydecanoate and α-cumylperoxyneodecanate as polymerization initiators, and the air in the polymerization reactor was discharged by a vacuum pump. Vinyl monomer 3.0
kg was added. Next, the temperature inside 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, unreacted vinyl chloride monomer was discharged to produce a composite vinyl chloride resin. The graft amount of vinyl chloride in the obtained composite vinyl chloride resin was 94%, and the content of the acrylic copolymer (C) was 6%. Further, the average degree of polymerization of the obtained composite vinyl chloride resin (E) was determined according to JIS K-6.
721, the average degree of polymerization was 140.
It was 0.

(3) Preparation of Vinyl Chloride Resin Composition and Rehabilitation Pipe In a Henschel mixer (manufactured by Kawada Kogyo Co., Ltd.) having an internal volume of 100 liters, 100 parts of the composite vinyl chloride resin (E) obtained above was heated, E as a plastic elastomer (F)
VACO (trade name "Elvaloy 742", manufactured by Du Pont-Mitsui Polychemicals) 10 parts, organic tin-based stabilizer (trade name "ONZ-142F", manufactured by Sankyo Co., Ltd.) 2 as a stabilizer
Part, polyethylene wax-based lubricant as a lubricant (trade name “Hiwax220MP”, manufactured by Mitsui Petrochemical Industries, Ltd.)
0.5 parts of stearic acid (trade name "S
-30 "(manufactured by Kao Corporation) and 3 parts of a trade name" METABLEN P501A "(manufactured by Mitsubishi Rayon Co., Ltd.) as a processing aid were uniformly mixed with stirring to prepare a vinyl chloride resin composition.

The obtained vinyl chloride resin composition was adjusted to a diameter of 9
0mm two-axis counter-rotating extruder (trade name "SLM-9
0 ", manufactured by Sekisui Koki Co., Ltd.) to obtain a vinyl chloride resin molded article having an outer diameter of 100 mm. After leaving the obtained molded body in a gear oven heated to 80 ° C. for 20 minutes, the cross section is made to have the shape shown in FIG. 1, and the temperature of the formed body is kept at 20 ° C. while maintaining this shape. After cooling, a rehabilitation pipe 1 was produced.

(4) Evaluation The performance (flexural modulus, impact resistance, workability) of the rehabilitated pipe obtained above was evaluated by the following method. 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: A Charpy impact value of a rehabilitated pipe was measured using a notched (notched) test piece in accordance with JIS K-7111 "Method for testing Charpy impact of hard plastic". The measurement was performed in an atmosphere at 23 ° C.

Workability: A rehabilitated pipe is inserted into a steel pipe having an inner diameter of 100 mm, and 90
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 tightness between the steel pipe and the vinyl chloride resin pipe was visually observed, and the workability was evaluated according to the following criteria. [Judgment criteria] ○ ‥‥ The rehabilitation pipe was completely in contact with the steel pipe × ‥‥ The rehabilitation pipe was not in close contact with the steel pipe partially or completely

Example 2 The graft amount of vinyl chloride was 9
2%, and the content of the acrylic copolymer (C) is 8%.
A vinyl chloride resin composition and a rehabilitated tube were produced in the same manner as in Example 1 except that the composite vinyl chloride resin (E) was used.

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

Example 4 A vinyl chloride resin composition was prepared in the same manner as in Example 1 except that the amount of EVACO “Elvaloy 742” was changed to 15 parts in the preparation of the vinyl chloride resin composition. And a rehabilitation pipe was produced.

Example 5 In the preparation of a vinyl chloride resin composition, EV was used as the thermoplastic elastomer (F).
NBR instead of 10 parts of ACO "Elvaloy 742"
(Product name "PN-20HA", manufactured by JSR Corporation)
A vinyl chloride-based resin composition and a rehabilitating tube were prepared in the same manner as in Example 1 except that 10 parts were added.

Example 6 In the production of a vinyl chloride resin composition, EV was used as the thermoplastic elastomer (F).
ACO "Elvaloy 742" 10 parts and NBR "PN-
Except for adding 5 parts of "20HA", a vinyl chloride resin composition and a rehabilitated tube were prepared in the same manner as in Example 1.

Comparative Example 1 A graft amount of vinyl chloride was 9
The vinyl chloride resin composition and the rehabilitation were carried out in the same manner as in Example 1 except that the composite vinyl chloride resin (E) having a content of 8% and an acrylic copolymer of 2% was used. A tube was made.

(Comparative Example 2) A vinyl chloride resin composition and a rehabilitation were performed in the same manner as in Example 1 except that the thermoplastic elastomer (F) was not added in the preparation of the vinyl chloride resin composition. A tube was made.

Comparative Example 3 A vinyl chloride resin composition was prepared in the same manner as in Example 1 except that the amount of EVACO "Elvaloy 742" was changed to 40 parts in the preparation of the vinyl chloride resin composition. And a rehabilitation pipe was produced.

Comparative Example 4 Composite Vinyl Chloride Resin (E)
Instead of using JIS K-672
A vinyl chloride resin composition and a rehabilitated tube were produced in the same manner as in Example 1, except that a vinyl chloride homopolymer having an average degree of polymerization of 1400 measured in accordance with Example 1 was used.

The performance (flexural modulus, impact resistance, workability) of the rehabilitated pipes obtained in Examples 2 to 6 and Comparative Examples 1 to 4 was determined in the same manner as in Example 1. evaluated. The results were as shown in Table 1.

[0061]

[Table 1]

As is clear from Table 1, Examples 1 to 6 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, when the graft amount of vinyl chloride is 9
The rehabilitation pipe of Comparative Example 1 comprising a vinyl chloride resin composition prepared using the composite vinyl chloride resin (E) having a content of 7% by weight or more (98% by weight), and the composite vinyl chloride resin (E) The retread tube of Comparative Example 4 made of a vinyl chloride resin composition prepared by using a vinyl chloride homopolymer instead of using the resin had extremely poor impact resistance.

The rehabilitating pipe of Comparative Example 2 comprising a vinyl chloride resin composition in which the thermoplastic elastomer (F) was not added to the composite vinyl chloride resin (E) had poor workability. Comparative Example 3 comprising a vinyl chloride resin composition in which the amount of the thermoplastic elastomer (F) (EVACO) added to 100 parts by weight of the composite vinyl chloride resin (E) exceeded 30 parts by weight (40 parts by weight). The rehabilitated pipe had a low flexural modulus (mechanical strength).

[0065]

As described above, the molded article of the vinyl chloride resin composition used in the present invention exhibits excellent mechanical strength and impact resistance. The vinyl chloride resin pipe for lining has excellent mechanical strength and impact resistance at a high level and also has excellent workability, and is suitably used for rehabilitating (restoring) an existing pipe.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a vinyl chloride resin tube for lining a protective tube according to the present invention.

[Explanation of symbols]

 1: Rehabilitation pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // (C08L 51/00 C08L 9:02) 9:02) (C08L 51/00 (C08L 51/00 23) : 08) 23:08) (C08L 51/00 (C08L 51/00 73:00) 73:00) B29K 9:00 B29K 9:00 23:00 23:00 27:06 27:06 G02B 6/00 351 F-term (reference) 2H038 CA68 3H111 AA02 BA15 BA34 CB02 DA26 DB23 4F211 AA04 AA15 AA18 AA20 AA45 AD12 AG03 AG08 AH43 SA13 SC03 SD04 SH06 SH18 SJ01 SP25 4J002 AC072 BB062 BN121 CJ002 A FD010 FD020 A00 030 AA68 AC34 BA01 BA02 BA03 BA05 BA09 BA10 BA11 BA15 BA19 BA27 BA30 BA38 BB01 BB03 BB04 DA03 DA04 DA07 DA12 DA14 DA15 DB02 DB03 DB04 DB38 EA04 FA07 GA08

Claims (1)

[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
100% by weight of an acrylic monomer component (A) containing less than 10% by weight and a polyfunctional monomer component (B)
3 to 10% by weight of an acrylic copolymer (C) obtained by copolymerizing 0.01 to 30 parts by weight is added to a vinyl chloride monomer or a vinyl chloride monomer and another copolymerizable monomer (D) 9
Average degree of polymerization 4 obtained by graft copolymerizing 7 to 90% by weight.
An acrylonitrile-butadiene copolymer was added to 100 parts by weight of the composite vinyl chloride resin (E) in the range of 00 to 2500,
Chloride obtained by adding 3 to 30 parts by weight of a thermoplastic elastomer (F) containing one or more selected from the group consisting of an ethylene-vinyl acetate copolymer and an ethylene-vinyl acetate-carbon monoxide copolymer. A vinyl chloride resin tube for a protective tube lining, comprising a vinyl resin composition, which is inserted into an existing tube and heated so as to adhere to the inner surface of the existing tube.