JP2004099697A - Chlorinated vinyl chloride-based resin composition for reforming pipe and reforming pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chlorinated vinyl chloride-based resin composition which is suitable for obtaining reforming pipes having excellent heat resistance and also having excellent workability and is used for the reforming pipes, and to provide the reforming pipe using the chlorinated vinyl chloride-based resin composition. <P>SOLUTION: This chlorinated vinyl chloride-based resin composition for the reforming pipes is characterized by containing a chlorinated vinyl chloride-based resin having a chlorine content of 58 to 71 wt. % as a main component and having a molded product flexural modulus of ≥450 MPa at 75°C, a flexural modulus (E, 20°C)/(E, 75°C) ratio of >1 to <20 at 20°C and 75°C, a flexural modulus (E, 75°C)/(E, 105°C) ratio of ≥2 at 75°C and 105°C, and a Vicat softening temperature (5 kg load) of ≥80°C according to JIS K 7026. <P>COPYRIGHT: (C)2004,JPO

Description

【００４５】
【表２】

【００４６】
【発明の効果】
本発明の更生管用塩素化塩化ビニル系樹脂組成物は、優れた耐熱性を有し、施工性にも優れる更生管を得るために適した更生管用塩素化塩化ビニル系樹脂組成物として好適に用いられる。また、本発明の更生管は、上記の本発明の塩素化塩化ビニル系樹脂組成物からなるので、優れた耐熱性を有し、既設管の更生（修復）用として好適に用いられる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a chlorinated vinyl chloride-based resin composition for a rehabilitation pipe and a chlorinated vinyl chloride-based resin rehabilitation pipe comprising the chlorinated vinyl chloride-based resin composition.
[0002]
[Prior art]
In recent years, aging existing pipes (porcelain pipes, fume pipes, steel pipes, etc.) have increased, but such existing pipes may be cracked or damaged due to corrosion or deterioration. As one of methods for rehabilitating and repairing aging existing pipes, vinyl chloride resin pipes having excellent mechanical strength, chemical resistance and the like are used.
[0003]
As a correction pipe made of such a vinyl chloride resin, a method of repairing the pipe by adding a thermoplastic elastomer that can be mixed with the vinyl chloride resin has been disclosed (for example, see Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent No. 3229319 (pages 1-3)
[0005]
However, in this method, since the main component of the rehabilitation pipe is a vinyl chloride resin, the heat resistance becomes insufficient in applications used at high temperatures, such as when used for rehabilitation of power cable protection pipes, and the rehabilitation pipe becomes poor. There was a problem that it was thermally deformed.
[0006]
[Problems to be solved by the invention]
An object of the present invention is to provide a chlorinated vinyl chloride-based resin composition for a rehabilitated pipe suitable for obtaining a rehabilitated pipe having excellent heat resistance and excellent workability in view of the above problems, and a chlorinated vinyl chloride-based resin composition thereof. An object of the present invention is to provide a retread tube using a resin composition.
[0007]
[Means for Solving the Problems]
The present invention has been made to achieve the above object, and the invention according to claim 1 (hereinafter referred to as invention 1) uses a chlorinated vinyl chloride resin having a chlorine content of 58 to 71% by weight. The flexural modulus of the molded article is 450 MPa or more at 75 ° C, and the ratio of the flexural modulus at 20 ° C and 75 ° C (E, 20 ° C) / (E, 75 ° C) is 1 Exceeding less than 20 and having a flexural modulus ratio of 75 ° C. and 105 ° C. (E, 75 ° C.) / (E, 105 ° C.) of 2 or more, and a Vicat softening temperature (5 kg load) in accordance with JIS K 7026 ) Is 80 ° C. or more.
In this specification, the flexural modulus at T ° C. of the molded body is expressed as (E, T ° C.).
[0008]
The invention according to claim 2 (hereinafter, referred to as invention 2) is inserted into an existing pipe and heated, or heated and applied with an internal pressure, so as to be closely attached to the inner surface of the existing pipe. A rehabilitation pipe comprising the chlorinated vinyl chloride resin composition according to claim 1.
[0009]
Hereinafter, the present invention will be described in more detail.
The chlorine content of the chlorinated vinyl chloride resin used in the present invention is limited to 58 to 71% by weight. If it is less than 58%, the heat resistance of the resulting chlorinated vinyl chloride resin composition and the rehabilitation pipe will be insufficient, and if the chlorine content exceeds 71%, molding will be difficult. Preferably it is 59 to 70% by weight, more preferably 60 to 69% by weight.
The chlorine content is a value determined by neutralization titration by an oxygen flask combustion method according to JIS K 7229.
[0010]
The chlorinated vinyl chloride resin is obtained by chlorinating the vinyl chloride resin. As the chlorination method, a conventionally known suspension method, solution chlorination method and the like are used, and the suspension method is industrially preferable. As a method of adjusting the chlorine content to the above range, it may be adjusted in the chlorination reaction stage, a chlorinated vinyl chloride resin having a high chlorine content and a chlorinated vinyl chloride resin having a low chlorine content, It may be adjusted by blending with a vinyl chloride resin.
[0011]
The vinyl chloride resin used in the production of the chlorinated vinyl chloride resin is not particularly limited as long as it is a vinyl chloride resin. Preferred are vinyl chloride resins obtained by the production methods described in JP-A-295701, JP-A-9-132612, JP-A-9-227607 and the like. Further, the degree of polymerization is preferably from 800 to 2000, more preferably from 800 to 1400.
[0012]
Examples of the vinyl chloride resin before chlorination include a vinyl chloride homopolymer, a copolymer of a monomer having an unsaturated bond copolymerizable with a vinyl chloride monomer and a vinyl chloride monomer, and vinyl chloride as a polymer. For example, a graft copolymer obtained by graft copolymerizing a monomer is used. In the present invention, these polymers may be used alone or in combination of two or more.
[0013]
Examples of the monomer having an unsaturated bond copolymerizable with the above-mentioned vinyl chloride monomer include α-olefins such as ethylene, propylene and butylene; vinyl esters such as vinyl acetate and vinyl propionate; butyl vinyl ether and cetyl Vinyl ethers such as vinyl ether; (meth) acrylate esters such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl acrylate, and phenyl methacrylate; aromatic vinyls such as styrene and α-methylstyrene; vinylidene chloride; Halogenated vinyl vinyls such as vinylidene halide; N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide; these may be used alone or in combination of two or more. .
[0014]
The polymer for graft-copolymerizing vinyl chloride is not particularly limited as long as it is a polymer for graft-polymerizing vinyl chloride. For example, ethylene-vinyl acetate copolymer; ethylene-vinyl acetate-carbon oxide copolymer Ethylene-ethyl acrylate copolymer; ethylene-butyl acrylate-carbon oxide copolymer; ethylene-methyl methacrylate copolymer; ethylene-propylene copolymer; acrylonitrile-butadiene copolymer; polyurethane; And the like, and these may be used alone or in combination of two or more.
[0015]
The polymerization method of the above vinyl chloride is not particularly limited, and a conventionally known suspension polymerization method, bulk polymerization method, solution polymerization method, emulsion polymerization method and the like are used, but the suspension polymerization method is preferred from the viewpoint of productivity.
[0016]
The chlorinated vinyl chloride resin composition for rehabilitating pipes of the present invention has a molded article having a flexural modulus of 450 MPa or more at 75 ° C, and a ratio of the flexural modulus at 20 ° C and 75 ° C (E, 20 ° C) / (E). , 75 ° C) is more than 1 and less than 20, and the ratio (E, 75 ° C) / (E, 105 ° C) of the flexural modulus between 75 ° C and 105 ° C is 2 or more.
If the flexural modulus at 75 ° C. is smaller than 450 MPa, the strength in the operating temperature range will be insufficient in applications requiring heat resistance. If the thickness of the rehabilitation pipe is increased to compensate for this, the moldability is lowered and the cost is increased, which is not appropriate.
When the ratio of the flexural modulus at 20 ° C. to 75 ° C. exceeds 20, the flexural modulus at 20 ° C. is as large as 9000 MPa or more, and the workability at the time of extrusion molding is significantly deteriorated. Although the lower limit of the elastic modulus in this range is not particularly limited from the viewpoint of moldability, it does not actually occur when the above ratio is 1 or less. Preferably it is more than 1 and less than 15, more preferably more than 1 and less than 10. Further, if the ratio of the flexural modulus at 75 ° C. and 105 ° C. is out of the above range, the inside of the rehabilitated pipe (for example, Ω-shaped cross section) is heated so as to be easily inserted into the existing pipe before construction. When the construction is carried out, the property of restoring and adhering to the inner peripheral surface of the existing pipe is deteriorated, and it is necessary to greatly raise the construction temperature. Preferably it is 3 or more. In order to achieve the above-mentioned range, the chlorine content of the chlorinated vinyl chloride resin is adjusted to 58 to 71% by weight, and a compounding agent for improving the extrudability is added as needed within a range not significantly lowering the heat resistance. It is necessary.
[0017]
Further, the chlorinated vinyl chloride resin composition has a Vicat softening temperature (5 kg load) according to JIS K 7026 of 80 ° C. or more. If the Vicat softening temperature is lower than 80 ° C., the rehabilitated pipe becomes insufficient for applications requiring heat resistance, such as a power cable protection pipe.
[0018]
The chlorinated vinyl chloride resin composition for rehabilitating pipes of the present invention comprises the above chlorinated vinyl chloride resin composition having a specific chlorine content as a main component, and further contains an additive. Examples of additives appropriately selected and contained include impact modifiers, thermoplastic elastomers, stabilizers, lubricants, processing aids, heat resistance improvers, antioxidants, ultraviolet absorbers, light stabilizers, and fillers. Agents, pigments and the like.
[0019]
The impact modifier is not particularly limited, and for example, methyl methacrylate-butadiene-styrene copolymer (MBS), chlorinated polyethylene, acrylic rubber and the like are used.
[0020]
A thermoplastic elastomer may be added to the chlorinated vinyl chloride resin composition for the purpose of improving workability. The thermoplastic elastomer is not particularly limited. For example, acrylonitrile-butadiene copolymer (NBR), ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl acetate-carbon oxide copolymer (EVACO), vinyl chloride -Vinyl chloride-based thermoplastic elastomers such as vinyl acetate copolymer and vinyl chloride-vinylidene chloride copolymer, styrene-based thermoplastic elastomer, olefin-based thermoplastic elastomer, urethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polyamide-based A thermoplastic elastomer or the like is used. These thermoplastic elastomers may be used alone or in combination of two or more.
[0021]
The above-mentioned stabilizer is not particularly limited, and for example, a heat stabilizer, a heat stabilization auxiliary, and the like are used. The heat stabilizer is not particularly limited, for example, dibutyltin mercapto, dioctyltin mercapto, dimethyltin mercapto, dibutyltin mercapto, dibutyltin malate, dibutyltin malate polymer, dioctyltin malate, dioctyltin malate polymer, dibutyltin Organotin stabilizers such as laurate and dibutyltin laurate polymers; lead stabilizers such as lead stearate, dibasic lead phosphite, and tribasic lead sulfate; calcium-zinc stabilizer; barium-zinc Stabilizers: Barium-cadmium stabilizers and the like are used. These may be used alone or in combination of two or more.
[0022]
The above stabilizing aid is not particularly limited, and for example, epoxidized soybean oil, phosphate, polyol, hydrotalcite, zeolite and the like are used. These may be used alone or in combination of two or more.
[0023]
As the above-mentioned lubricant, an internal lubricant and an external lubricant are used.
The internal lubricant is used for the purpose of reducing the flow viscosity of the molten resin at the time of molding and preventing frictional heat generation. The internal lubricant is not particularly limited, and examples thereof include butyl stearate, lauryl alcohol, stearyl alcohol, epoxy soybean oil, glycerin monostearate, stearic acid, and bisamide. These may be used alone or in combination of two or more.
The above-mentioned external lubricant is used for the purpose of increasing the sliding effect between the molten resin and the metal surface during molding. The external lubricant is not particularly limited, and for example, paraffin wax, polyolefin wax, ester wax, montanic acid wax and the like are used. These may be used alone or in combination of two or more.
[0024]
The processing aid is not particularly limited, and for example, an acrylic processing aid such as an alkyl acrylate-alkyl methacrylate copolymer having a weight average molecular weight of 100,000 to 2,000,000 is used. The acrylic processing aid is not particularly limited, and for example, an n-butyl acrylate-methyl methacrylate copolymer, a 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymer, or the like is used. These may be used alone or in combination of two or more.
[0025]
The heat-resistant improver is not particularly limited, and for example, α-methylstyrene-based, N-phenylmaleimide-based resins and the like are used.
[0026]
The antioxidant is not particularly limited, and for example, a phenolic antioxidant is used.
[0027]
The light stabilizer is not particularly limited, and for example, a hindered amine light stabilizer or the like is used.
[0028]
The above-mentioned ultraviolet absorber is not particularly limited, and for example, a salicylic acid ester-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based ultraviolet absorber and the like are used.
[0029]
The filler is not particularly limited, and for example, calcium carbonate, talc, or the like is used.
[0030]
The above-mentioned pigments are not particularly limited and include, for example, organic pigments such as azo-based, phthalocyanine-based, sulene-based and dye lake-based; oxide-based, molybdenum chromate-based, sulfide / selenide-based, ferrocyanide-based, and the like. Inorganic pigments and the like are used.
[0031]
In the above chlorinated vinyl chloride resin composition, a plasticizer may be added for the purpose of improving workability at the time of molding, but since the heat resistance of the molded article may be reduced, a large amount may be used. Its use is not preferred. The plasticizer is not particularly limited, and for example, dibutyl phthalate, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate and the like are used.
[0032]
The method of mixing the above additives with the above chlorinated vinyl chloride resin is not particularly limited, and for example, a method using hot blending, a method using cold blending, or the like is used.
[0033]
The rehabilitation pipe of Invention 2 is usually produced by extruding with an extruder using the chlorinated vinyl chloride resin composition of Invention 1, inserted into an existing pipe and heated, or It is characterized in that it is brought into close contact with the inner surface of the existing pipe by being heated and applied with internal pressure.
[0034]
The cross-sectional shape of the rehabilitating pipe can be inserted into an existing pipe to be rehabilitated and repaired, and can be inserted into the inner surface of the existing pipe by being heated or by being heated and applied with an internal pressure. The shape is not particularly limited as long as it has a shape that can be in close contact, but is preferably an Ω shape.
[0035]
【Example】
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. In the examples, “parts” means “parts by weight”, and “%” means “% by weight”.
[0036]
(Examples 1 to 5)
(1) Preparation of chlorinated vinyl chloride resin composition According to the composition shown in Table 1, each raw material was stirred and mixed with a 200 L "Supermixer" (manufactured by Kawata) to obtain a chlorinated vinyl chloride resin composition. .
The grade and manufacturer name of each material are as follows.
Chlorinated vinyl chloride resin A; "HA-54K" manufactured by Tokuyama Sekisui Industry Co., Ltd., degree of polymerization 1000
Chlorinated vinyl chloride resin B; "HA-54H" manufactured by Tokuyama Sekisui Industry Co., Ltd., degree of polymerization 1000
Chlorinated vinyl chloride resin C; "HA-54F" manufactured by Tokuyama Sekisui Industry Co., Ltd., degree of polymerization 1000
Chlorinated vinyl chloride resin D; chlorination degree 73%, "TS-1000R" (degree of polymerization 1050) Chlorinated vinyl chloride resin A manufactured by Tokuyama Sekisui Industry Co., Ltd .; "TS-1000R" (degree of polymerization 1050) ) Thermoplastic elastomer A (EVACO) manufactured by Tokuyama Sekisui Kogyo Co., Ltd .; "Elvaloy 742"; heat stabilizer A manufactured by Mitsui / Dupont Polychemical Co., Ltd .; "ONZ-100F" manufactured by Mitsui Organic Synthesis, organic tin Stabilizer heat stabilizer B; "ONZ-6F" manufactured by Mitsui Organic Synthesis Co., Ltd .; organic tin stabilizer lubricant A; "Hiwax 2203A" manufactured by Mitsui Chemicals, Inc .; polyethylene wax lubricant B; "SL800" Riken Vitamin Co., Ltd. ), Stearyl stearate lubricant C; "Loxiol G21" 12-hydroxystearic acid impact modifier A, manufactured by Cognis Japan K.K .; "M511" Kanegafuchi Chemical MBS resin manufactured by Co., Ltd.
(2) Molding of rehabilitating pipe The chlorinated vinyl chloride resin composition obtained by the above method is supplied to a 50 mm-diameter two-axis counter-rotating extruder “SLM-50” (manufactured by Nagata Seisakusho) to form a melt. Obtained. The obtained melt was cooled with water at 20 ° C. to obtain a tubular body having an outer diameter of 50 mm and a wall thickness of 4.5 mm. After leaving this tubular body in a gear open heated to 110 ° C. for 20 minutes, the tubular body section is made into a four-fold shape, and the temperature of the molded body is kept at 20 ° C. while maintaining this shape. Upon cooling, a rehabilitated tube was obtained.
[0038]
(3) The chlorine content of the evaluation resin, the Vicat softening temperature of the rehabilitated tube, the flexural modulus, the insertability and the resilience were evaluated. The evaluation method is as follows. The results are summarized in Table 2.
(1) Measurement of chlorine content The chlorine weight content (Cl%) of CPVC was measured according to JIS K7229.
{Circle around (2)} Vicat softening temperature Vicat softening temperature was measured in accordance with the Vicat softening temperature test method (JIS K 7206) for thermoplastics. A 5 kg weight was used for the measurement.
{Circle around (3)} Flexural modulus The flexural modulus at 20 ° C., 75 ° C. and 105 ° C. was measured in accordance with the bending test method (JIS K7171) for hard plastics.
[0039]
(4) Evaluation of insertability After hot air of 80 ° C. was blown into the rehabilitation pipe from one end of the rehabilitation pipe for 10 minutes, the rehabilitation pipe was inserted into a 45 ° L-shaped steel pipe having an inner diameter of 50 mm, and the following criteria were used. Was used to evaluate the insertability.
○ ‥‥ Insertion was possible and there was no damage such as cracking or whitening.
× ‥‥ Insertion was impossible or damage such as cracking or whitening was observed.
(5) Evaluation of resilience Insert the rehabilitated pipe into a steel pipe with an inner diameter of 50 mm, blow steam of 110 ° C into the rehabilitated pipe from one end of the rehabilitated pipe for 10 minutes, and adhere the rehabilitated pipe to the inner surface of the steel pipe. I let it. Then, after cooling by blowing air at 20 ° C. for 30 minutes, the adhesion between the steel pipe and the rehabilitated pipe was visually observed, and the resilience was evaluated according to the following criteria.
○ ‥‥ The rehabilitated pipe was in full contact with the steel pipe.
×: The rehabilitated pipe was not completely adhered to the steel pipe.
[0040]
(Comparative Examples 1 to 3)
(1) Preparation of Vinyl Chloride Resin Composition In the same manner as in Examples 1 to 5, each raw material was stirred and mixed with a 200 L “Supermixer” (manufactured by Kawata Co., Ltd.) according to the composition shown in Table 1. A resin composition was obtained.
[0041]
(2) Preparation of Chlorinated Vinyl Chloride Resin D of Comparative Example 3 180 kg of deionized water and 20 kg of PVC (trade name “TS-1000R” Tokuyama Sekisui Kogyo Co., Ltd.) were placed in a 300 liter glass-lined pressure-resistant reaction tank having an internal volume of 300 liters. Then, the mixture was stirred and dispersed in water to disperse the PVC, and the internal air was sucked by a vacuum pump, and the pressure was reduced until the gauge pressure became -78.4 KPa. The pressure was returned with nitrogen gas (returned until the gauge pressure became 0), and the inside of the reaction tank was removed by suction with a vacuum pump again. During this time, the inside of the reactor was heated by passing the heated oil through the jacket.
When the temperature in the reaction tank reached 80 ° C, the supply of chlorine gas was started, and the reaction was allowed to proceed at a constant temperature of 110 ° C. The chlorine content of PVC in the reactor is calculated from the concentration of hydrogen chloride generated in the reaction tank, and when the chlorine content reaches 63% by weight, the reaction temperature is raised to 120 ° C, and a hydrogen peroxide solution having a concentration of 500 ppm is added. The reaction was continued while adding continuously at 0.5 kg / hr. Further, when the chlorine content reached 68% by weight, the concentration of the hydrogen peroxide solution was changed to 1000 ppm, and the reaction was continued. When the chlorination content reached 72% by weight, the supply of chlorine gas was stopped, and the chlorination reaction was terminated. The amount of hydrogen peroxide added during the reaction was 2500 ppm based on the charged resin. Further, nitrogen gas was blown into the reaction tank to remove unreacted chlorine, and the obtained resin was washed with water, dehydrated and dried to obtain a powdery chlorinated vinyl chloride resin. The chlorine content of the obtained chlorinated vinyl chloride resin was 73% by weight.
[0042]
(3) Preparation of Rehabilitation Tube The vinyl chloride resin was stirred and mixed with a 200 L supermixer (manufactured by Kawata Corporation) according to the composition shown in Table 1 to obtain a vinyl chloride resin composition. A rehabilitated tube was produced in the same manner as in Example 1.
[0043]
(4) Evaluation In the same manner as in Examples 1 to 5, the chlorine content of the resin, the Vicat softening temperature, the flexural modulus, the insertability and the resilience of the rehabilitated pipe were evaluated. The results are summarized in Table 2.
[0044]
[Table 1]

[0045]
[Table 2]

[0046]
【The invention's effect】
The chlorinated vinyl chloride resin composition for rehabilitation pipes of the present invention has excellent heat resistance and is suitably used as a chlorinated vinyl chloride resin composition for rehabilitation pipes suitable for obtaining a rehabilitation pipe excellent in workability. Can be Moreover, since the rehabilitation pipe of the present invention is composed of the above-mentioned chlorinated vinyl chloride resin composition of the present invention, it has excellent heat resistance and is suitably used for rehabilitating (restoring) an existing pipe.

Claims (2)

It contains a chlorinated vinyl chloride resin having a chlorine content of 58 to 71% by weight as a main component, and has a flexural modulus of elasticity of 450 MPa or more at 75 ° C, and a flexural modulus at 20 ° C and 75 ° C. The ratio (E, 20 ° C.) / (E, 75 ° C.) is more than 1 and less than 20, and the ratio of the flexural modulus at 75 ° C. to 105 ° C. (E, 75 ° C.) / (E, 105 ° C.) is 2 A chlorinated vinyl chloride resin composition for a rehabilitation pipe, wherein the composition has a Vicat softening temperature (5 kg load) according to JIS K 7026 of 80 ° C or more. The chlorinated vinyl chloride resin composition according to claim 1, wherein the chlorinated vinyl chloride resin composition is inserted into an existing pipe and heated, or adhered to the inner surface of the existing pipe by being heated and subjected to internal pressure. A rehabilitating tube that is characteristic.