JP2008013632A - Vinyl chloride-based resin composition for restored pipe and vinyl chloride-based resin restored pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vinyl chloride-based resin composition for restored pipes which is suitable for obtaining restored pipes having both excellent mechanical strength and impact resistance, and excellent laying properties as well and a vinyl chloride-based resin restored pipe using the vinyl chloride-based resin composition. <P>SOLUTION: The vinyl chloride-based resin composition for restored pipes comprises 100 pts.wt. composite vinyl chloride-based resin obtained by graft copolymerization of 70-99 wt.% vinyl monomer having vinyl chloride as the major component onto 1-30 wt.% acrylic copolymer, 10-30 pts.wt. thermoplastic elastomer which is compatible with the composite vinyl chloride-based resin, and 1-10 pts.wt. needle or plate inorganic substance. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vinyl chloride resin composition for rehabilitation pipes and a vinyl chloride resin rehabilitation pipe using the vinyl chloride resin composition.

  In recent years, the number of existing pipes that have deteriorated has increased, and as one of the methods for repairing such old pipes, there is a method using a vinyl chloride resin pipe having excellent mechanical strength and chemical resistance. is there.

For example, a method of repairing with a resin tube in which a thermoplastic elastomer that can be mixed with a vinyl chloride resin is added is disclosed (Patent Document 1). However, in the case of this method, it is necessary to add a large amount of thermoplastic elastomer, impact modifier, etc. in order to develop impact resistance sufficient to prevent breakage of the resin pipe during transportation and construction. There is a problem that the mechanical strength of the obtained resin pipe becomes insufficient.
JP-T 6-508647

  In view of the above problems, the object of the present invention is to provide a rehabilitated pipe vinyl chloride resin composition suitable for obtaining a rehabilitated pipe having both excellent mechanical strength and impact resistance and excellent workability, and its vinyl chloride type An object of the present invention is to provide a vinyl chloride resin rehabilitating tube using a resin composition.

The first vinyl chloride resin composition for rehabilitation pipe of the present invention (hereinafter simply abbreviated as “vinyl chloride resin composition”) is mainly composed of vinyl chloride in 1 to 30% by weight of an acrylic copolymer. 10 to 30 parts by weight of the thermoplastic elastomer that is compatible with the composite vinyl chloride resin is added to 100 parts by weight of the composite vinyl chloride resin obtained by graft copolymerization of 70 to 99% by weight of vinyl monomer. It is characterized by adding 1 to 10 parts by weight of a needle-like or plate-like inorganic substance.
In this vinyl chloride resin composition, it is preferable that 3 to 10 parts by weight of an impact modifier is further added.

Further, the second vinyl chloride resin composition for rehabilitation pipe of the present invention (hereinafter simply abbreviated as “vinyl chloride resin composition”) is added to 100 parts by weight of vinyl chloride resin having an average degree of polymerization of 600 to 3000. On the other hand, the addition amount of the thermoplastic elastomer having a low glass transition point or a low melting point compound A (excluding the thermoplastic elastomer) compatible with the vinyl chloride resin is 10 to 30 parts by weight, and the needle-like or plate-like inorganic substance is 1 10 to 10 parts by weight, and 3 to 30 parts by weight of an impact modifier is added.
These vinyl chloride resin compositions may further contain 10 to 30 parts by weight of a compound A (excluding thermoplastic elastomer) having a low glass transition point or a low melting point.

  In these vinyl chloride resin compositions, (1) the acrylic copolymer has a glass transition temperature of −140 ° C. or higher and lower than 0 ° C., and is a radical mainly composed of at least one (meth) acrylate. It is an acrylic copolymer composed of 100 parts by weight of a polymerizable monomer and 0.1 to 10 parts by weight of a polyfunctional monomer, or (2) the glass transition temperature of the homopolymer is −140 ° C. or higher— The glass transition temperature of the homopolymer is −55 ° C. or more and 0 to less than 60 ° C. and 40 to 90% by weight of the copolymer of 100 parts by weight of the radical polymerizable monomer and 0.1 to 1 part by weight of the polyfunctional monomer. Graft copolymerization of 10 to 60% by weight of mixed monomer of 100 parts by weight of radically polymerizable monomer mainly composed of (meth) acrylate having a temperature of less than 0 ° C. and 1.5 to 10 parts by weight of polyfunctional monomer Core - made of shell structure is preferred.

  The molded body made of the vinyl chloride resin composition for rehabilitation pipes preferably has a flexural modulus of 1470 Mpa or more at 20 ° C. and 50 to 1470 Mpa at 50 ° C.

  Further, the needle-like or plate-like inorganic material preferably has an aspect ratio of 10 or more and is composed of a metal composite oxide, and the thermoplastic elastomer compatible with the composite vinyl chloride resin is urethane having a molecular weight of 1000 to 60,000. It is preferable to contain a base elastomer or the urethane elastomer and an ester plasticizer having a molecular weight of 20000 or less.

  The vinyl chloride resin rehabilitation pipe of the present invention comprises a vinyl chloride resin composition for rehabilitation pipes and an existing pipe, and the vinyl chloride resin composition for rehabilitation pipes is inserted into the existing pipe and heated. This is characterized in that it is in close contact with the inner surface of the existing pipe.

  The vinyl chloride resin composition of the present invention expresses excellent mechanical strength and impact resistance, and is excellent in workability when used as a rehabilitated pipe, and therefore is suitably used as a resin for producing a rehabilitated pipe. be able to.

  In addition, the rehabilitated pipe of the present invention contains the vinyl chloride resin composition of the present invention, so that it has excellent mechanical strength and impact resistance at a high level, and has excellent workability, It can be suitably used for rehabilitation (restoration) of existing pipes.

  The first vinyl chloride resin composition of the present invention comprises a composite vinyl chloride resin, a thermoplastic elastomer, and a needle-like or plate-like inorganic substance. The first vinyl chloride resin composition may optionally contain a low glass transition point or a low melting point compound A and an impact modifier.

  From another viewpoint, the second vinyl chloride resin composition of the present invention includes a vinyl chloride resin, a thermoplastic elastomer, a needle-like or plate-like inorganic substance, and an impact modifier. . The second vinyl chloride resin composition may optionally contain a low glass transition point or a low melting point compound A.

  The thermoplastic elastomer used in the present invention is compatible with the later-described composite vinyl chloride resin or vinyl chloride resin, and the type thereof is not particularly limited. For example, acrylonitrile-butadiene copolymer (NBR) ), Ethylene-vinyl acetate copolymers (EVA), ethylene-vinyl acetate-carbon monoxide copolymers (EVACO), vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinylidene chloride copolymers, etc. Examples thereof include thermoplastic elastomers, styrene thermoplastic elastomers, olefin thermoplastic elastomers, polyester thermoplastic elastomers, polyamide thermoplastic elastomers, urethane elastomers (for example, those produced from isocyanates and polyols), and the like. These can be used alone or in combination of two or more.

  Especially, the urethane type elastomer manufactured by isocyanate and a polyol is preferable from a viewpoint that it has a high elasticity modulus until the crystal part which melt | dissolves melt | dissolves, and when a crystal part melt | dissolves, an elastic modulus will fall rapidly. In other words, the bending elasticity is high at normal temperature (the folded shape is maintained), and the bending elasticity is low at high temperature (when heated, it softens and the circular shape recovers and adheres to the old pipe). In particular, those having a low molecular weight have excellent compatibility with composite vinyl chloride resins and vinyl chloride resins, good thermal stability, and contribute to a decrease in elastic modulus even at 50 ° C. or higher. From the viewpoint of improving the moldability of the resin composition, those having a molecular weight of 1000 or more and 60000 or less are preferred.

  Moreover, impact strength can be improved by using ethylene-vinyl acetate-carbon monoxide copolymer (EVACO) together with urethane elastomer. In this case, the ethylene-vinyl acetate-carbon monoxide copolymer is preferably, for example, 30 to 70% by weight of the combined amount with the urethane elastomer.

  The isocyanate which comprises a polyurethane-type elastomer is not specifically limited, Any may be used. For example, tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate and the like can be mentioned. The polyol is not particularly limited, and any of them may be used. Examples thereof include polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol.

  The compound A having a low glass transition point or a low melting point optionally used in the present invention excludes a thermoplastic elastomer and is compatible with a vinyl chloride homopolymer or a composite vinyl chloride resin mainly composed of vinyl chloride. And the melting point or dropping point is lower than the glass transition point of the resin. Examples of such compound A include plasticizers and antioxidants. However, the low glass transition point or the low melting point compound A, and the above-mentioned thermoplastic elastomers are usually impact modifiers such as those used in vinyl chloride resins, such as methyl methacrylate-butadiene-styrene resin (MBS), acrylonitrile- Acrylic rubber such as butadiene-styrene resin (ABS) is not included.

  The plasticizer or antioxidant is not particularly limited as long as it satisfies the above conditions. For example, ester plasticizers such as dicyclohexyl phthalate (DCHP) or triphenyl phosphate (TPP), ethylphthalyl ethylglycolate, adipic acid polyester, and dimyristyl thiopropionate (DMTP) are preferably used. These can be used alone or in combination of two or more. In particular, when used with the urethane elastomer, ester plasticizers are preferable because they are excellent in compatibility with composite vinyl chloride resins and vinyl chloride resins. In this case, it is preferable to use a high molecular weight having a softening temperature or a melting temperature of 50 ° C. to 60 ° C., but a molecular weight of 20000 or less is preferable from the viewpoint of easy handling.

  The thermoplastic elastomer and / or the low glass transition point or low melting point compound A (excluding the thermoplastic elastomer) is 10 to 10 parts by weight in total of these components with respect to 100 parts by weight of the composite vinyl chloride resin or vinyl chloride resin. It is desirable to add 30 parts by weight. If the addition amount is less than 10 parts by weight, the workability when inserting the rehabilitation pipe made of the vinyl chloride resin composition into the existing pipe and heating it to adhere to the existing pipe may be impaired. If it exceeds 30 parts by weight, the mechanical strength of the resulting vinyl chloride resin composition and rehabilitated pipe may be insufficient.

  Examples of the needle-like inorganic substance used in the present invention include wollastonite, potassium titanate, basic magnesium sulfate, sepiolite, zonotlite, aluminum borate and the like, as the plate-like inorganic substance, talc, mica, synthetic hydrosartite, Examples include plate-like calcium carbonate. Of these, metal composite oxides are preferable. The metal complex oxide means, for example, an oxide, carbonate, silicate or the like containing magnesium, titanium, potassium, aluminum, potassium or the like. When the metal composite oxide is used, the interfacial force can be improved by the interaction with the vinyl chloride resin composition by the functional group or metal ion on the particle surface, and the mechanical strength can be improved. These can be used alone or in combination of two or more. Here, the needle shape means a particle shape such as a needle shape, a rod shape, a fiber shape, a spindle shape, or a columnar shape whose major axis is three times or more the minor axis. The plate shape includes not only a so-called plate shape but also a scale shape and a flake shape. Especially, from a viewpoint of improving mechanical strength, especially a bending elastic modulus, as an acicular or plate-shaped inorganic substance, aspect ratio is 10 or more, Furthermore, 20 or more, 30 or more are preferable. Here, the aspect ratio means a length / diameter or length / thickness ratio.

  The added amount of the inorganic substance is desirably 1 to 10 parts by weight with respect to 100 parts by weight of the composite vinyl chloride resin or vinyl chloride resin. If the addition amount is less than 1 part by weight, the effect of improving the mechanical strength is insufficient, and if it exceeds 10 parts by weight, the impact resistance is lowered.

  The impact modifier used in the present invention is not particularly limited, and examples thereof include methyl methacrylate-butadiene-styrene copolymer, chlorinated polyethylene, and acrylic modifier. These can be used alone or in combination of two or more.

  The addition amount of the impact modifier is preferably 3 to 30 parts by weight with respect to 100 parts by weight of the vinyl chloride resin from the viewpoint of imparting appropriate mechanical strength and preventing deterioration of moldability. In particular, when added to the composite vinyl chloride resin, the content is preferably 3 to 10 parts by weight with respect to 100 parts by weight of the composite vinyl chloride resin from the viewpoint of compensating for the reduction in impact resistance due to the inorganic compounding. The amount can be reduced by the rubber component in the composite vinyl chloride resin as compared with the amount to be added to the vinyl chloride resin.

  The composite vinyl chloride resin used in the present invention is obtained by graft copolymerizing a vinyl monomer with an acrylic copolymer.

  The acrylic copolymer is blended in order to improve the impact resistance of the composite vinyl chloride resin to be produced, and is preferably flexible at room temperature. The glass transition temperature of this homocopolymer is The glass transition temperature is preferably less than −60 ° C. from the viewpoint of improving impact resistance and giving sufficient flexibility to high-speed strain. In view of the glass transition temperature of polymers generally used industrially, those having a temperature of −140 ° C. or higher are suitable.

  The type of the acrylic copolymer is not limited, but a copolymer comprising a radical polymerizable monomer and a polyfunctional monomer, particularly a radical polymerizable monomer mainly comprising at least one (meth) acrylate. And an acrylic copolymer composed of a polyfunctional monomer.

  Although it does not specifically limit as a radical polymer monomer, For example, n-butyl acrylate, n-heptyl acrylate, n-octyl acrylate, 2-methyl heptyl acrylate, 2-ethylhexyl acrylate, n-nonyl acrylate, 2-methyl octyl acrylate 2-ethylheptyl acrylate, n-decyl acrylate, 2-methylnonyl acrylate, 2-ethyloctyl acrylate and the like are preferably used. These can be used alone or in combination of two or more.

  The polyfunctional monomer improves the impact resistance of the composite vinyl chloride resin and the vinyl chloride resin, and further, when the acrylic copolymer is produced and after the acrylic copolymer particles are fused. Formulated to suppress.

  Examples of the multifunctional monomer include di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and 1,6-hexanediol di (meth). Acrylate, trimethylolpropane di (meth) acrylate, and the like. As tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) An acrylate etc. are mentioned. Other polyfunctional monomers include pentaerythritol tetra (meth) acrylate, dipentaerythrole hexa (meth) acrylate, diallyl phthalate, diallyl malate, diallyl fumarate, diallyl succinate, triallyl isocyanurate, etc. Or divinyl compounds such as divinylbenzene and butadiene. These can be used alone or in combination of two or more.

  When a polyfunctional monomer is used in an acrylic copolymer, the blending amount of the acrylic copolymer can maintain an independent particle shape in the composite vinyl chloride resin or vinyl chloride resin and From the viewpoint of maintaining the impact resistance of the composite vinyl chloride resin or vinyl chloride resin by keeping the crosslinking density of the copolymer in an appropriate range. 0.1 to 10 parts by weight is suitable for 100 parts by weight).

  The acrylic copolymer may be a copolymer having a single structure, but has, for example, a core-shell structure (a granular structure comprising a central part and an outer shell part covering the central part). Is preferred.

  In this case, the core may be formed of any material, and examples thereof include (co) polymers of radical polymerizable monomers or (co) polymers of radical polymerizable monomers and polyfunctional monomers. Is done.

    In particular, the copolymer constituting the core preferably has a glass transition temperature of −140 ° C. or higher and lower than −60 ° C. Thereby, the impact resistance of the composite vinyl chloride resin or the vinyl chloride resin can be improved. In particular, it is preferable to have sufficient flexibility against high-speed distortion. The radical polymerizable monomer used for constituting the core is not particularly limited, and examples thereof include a (meth) acrylate monomer and a polyfunctional monomer. Specific examples include those exemplified above as “radical polymer monomers” and “polyfunctional monomers”. Moreover, what was mentioned above is mentioned as a polyfunctional monomer.

  Moreover, it is preferable that at least the shell is formed of an acrylic copolymer composed of a radical polymerizable monomer mainly composed of one or more (meth) acrylates and a polyfunctional monomer.

  The copolymer constituting the shell preferably has its own glass transition temperature of −55 ° C. or higher and lower than 0 ° C. As a result, the impact resistance of the vinyl chloride resin can be improved and the low glass transition polymer of the core can be coated to reduce the adhesiveness of the acrylic copolymer particles. In particular, it is preferable to maintain a certain degree of flexibility. The type of radically polymerizable monomer used for constituting the shell is not particularly limited, and those described above can be used. (Meth) acrylate monomers such as ethyl acrylate, n-propyl acrylate, isopropyl acrylate , N-butyl (meth) acrylate, isobutyl acrylate, sec-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, cumyl acrylate, n-heptyl methacrylate, n-octyl methacrylate, 2-methylheptyl methacrylate, 2-ethylhexyl Methacrylate, n-nonyl methacrylate, 2-methyloctyl methacrylate, 2-ethylheptyl methacrylate, n-decyl methacrylate, 2-methylnonyl methacrylate, 2-ethyl Chi methacrylate, lauryl (meth) acrylate is preferably used. These can be used alone or in combination of two or more.

  In the present invention, the glass transition temperature indicates the glass transition temperature of the acrylic copolymer itself. For example, in the case of a core-shell structure, the glass transition temperature of the copolymer constituting the core, the shell It means the glass transition temperature of the constituting copolymer. The glass transition temperature is expressed in accordance with “Polymer Data Handbook (Basic)” edited by the Society of Polymer Science, Japan (1986, Baifukan).

  In the present invention, examples of the method of copolymerizing a radical polymerizable monomer containing (meth) acrylate and a polyfunctional monomer include an emulsion polymerization method and a suspension polymerization method. Among these, the emulsion polymerization method is desirable because it has good impact resistance and can easily control the particle size of the acrylic copolymer. The copolymerization includes all copolymerization such as random copolymerization, block copolymerization, and graft copolymerization.

  The emulsion polymerization method can be carried out by a conventionally known method with the addition of an emulsifying dispersant, a polymerization initiator, a pH adjuster, an antioxidant and the like, if necessary.

  An emulsifying dispersant improves the dispersion stability of a mixture of a radically polymerizable monomer containing (meth) acrylate and a polyfunctional monomer (hereinafter also referred to as “mixed monomer”) in an emulsion, thereby efficiently performing polymerization. It is used to do this. For example, anionic surfactants, nonionic surfactants, partially saponified polyvinyl acetate, cellulose dispersants, gelatin and the like can be mentioned.

  The polymerization initiator is not particularly limited, and examples thereof include water-soluble polymerization initiators such as potassium persulfate, ammonium persulfate, and hydrogen peroxide, organic peroxides such as benzoyl peroxide and lauroyl peroxide, azobisiso Examples include azo initiators such as butyronitrile.

Any pH adjusting agent known in the art may be used.
Examples of the antioxidant include phenolic antioxidants.
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 and a mixed monomer are added all at once in a jacketed polymerization reactor, and the mixture is stirred and emulsified under a nitrogen stream under pressure. This is a method in which the temperature is raised to 1 and then polymerized.

  In the monomer dropping method, pure water, an emulsifying dispersant and a polymerization initiator are placed in a jacketed polymerization reactor, oxygen is removed and pressurized under a nitrogen stream, and the temperature inside the reactor is raised to a predetermined temperature by a jacket. Thereafter, the mixed monomer is dropped and polymerized by a certain amount.

  In the emulsion dropping method, a mixed monomer, an emulsifying dispersant and pure water are stirred to prepare an emulsified monomer in advance, and then pure water and a polymerization initiator are placed in a jacketed polymerization reactor to remove oxygen under a nitrogen stream. In this method, pressurization is carried out, the temperature inside the reactor is raised to a predetermined temperature by a jacket, and then an emulsified monomer is added dropwise in a predetermined amount for polymerization.

  In particular, when the acrylic copolymer has a core-shell structure, for example, first, a mixed monomer that forms a core [radical polymerizable monomer + polyfunctional monomer added as necessary], pure water and an emulsifier A polymerization initiator is added to the emulsified monomer prepared from the above to conduct a polymerization reaction, thereby forming core resin particles. Next, a mixed monomer constituting the shell (a radically polymerizable monomer having (meth) acrylate as a main component + a polyfunctional monomer added as necessary), an emulsified monomer prepared from pure water and an emulsifier, is added to the core. Examples thereof include a method of graft copolymerizing the shell.

  In the acrylic copolymer thus obtained, the shell part three-dimensionally covers the surface of the core part, and the copolymer constituting the shell part and the (co) polymer constituting the core part are partially Are covalently bonded, and the shell portion forms a three-dimensional crosslinked structure. In the above method, the graft copolymerization of the shell part may be continuously performed in the same polymerization step as the polymerization of the core part.

  The ratio of the core to the shell can be adjusted by adjusting the ratio of the mixed monomer forming the core and the mixed monomer forming the shell in the emulsion polymerization method. For example, it is preferable to copolymerize 10 to 60% by weight of the shell copolymer with respect to 40 to 90% by weight of the core (co) polymer.

  In the polymerization method as described above, the solid content ratio of the acrylic copolymer obtained after completion of the reaction is preferably 10 to 60% by weight from the viewpoint of the productivity of the acrylic copolymer and the stability of the polymerization reaction.

  The vinyl monomer used in the present invention is preferably composed mainly of vinyl chloride. Here, the main component means a component occupying 50% or more of the total weight of the vinyl monomer.

  Vinyl monomers include monomers or polymers copolymerizable with vinyl chloride monomers, for example, α-olefins such as ethylene, propylene and butylene: vinyl esters such as vinyl acetate and vinyl propionate: ethyl vinyl ether, butyl vinyl ether, etc. Vinyl ethers: (meth) acrylic acid esters such as methyl (meth) acrylate, butyl (meth) acrylate and hydroxyethyl (meth) acrylate; aromatic vinyls such as styrene and α-methylstyrene; vinyl fluoride and fluoride Vinyl halides such as vinylidene and vinylidene chloride; N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide; acrylic copolymers composed of alkyl (meth) acrylate monomers and the like may be included. . These may be used alone or in combination of two or more.

  The composite vinyl chloride resin of the present invention has the above-mentioned acrylic resin from the viewpoint that the produced composite vinyl chloride resin has sufficient impact resistance and prevents a decrease in mechanical strength such as bending strength and tensile strength. It is obtained by graft polymerization of 1 to 30% by weight of copolymer and 70 to 99% by weight of vinyl chloride monomer. In particular, the preferable blending amount of the acrylic copolymer is 4 to 20% by weight.

  The acrylic copolymer in the composite vinyl chloride resin has an average particle diameter of 0.01 to 1 μm from the viewpoint of preventing mold adhesion and appearance failure during molding, and preventing a decrease in impact resistance and mechanical strength. It is preferable that

  The polymerization degree of polyvinyl chloride in the composite vinyl chloride resin is suitably 300 to 2500, preferably 400 to 1600, since it is difficult to obtain a sufficient moldability of the molded product if it is too small or too large. It is.

  There is no particular limitation on the method of graft-copolymerizing the above acrylic copolymer with a vinyl monomer containing vinyl chloride as a main component. For example, suspension polymerization, emulsion polymerization, solution polymerization, bulk polymerization, etc. Is mentioned. Of these, suspension polymerization is preferred.

When the polymerization is performed by the suspension polymerization method, a dispersant, a polymerization initiator, or the like may be used.
The dispersant is added for the purpose of improving the dispersion stability of the acrylic copolymer and efficiently performing graft polymerization of vinyl chloride. The type is not particularly limited, but examples thereof include poly (meth) acrylate, (meth) acrylate-alkyl acrylate copolymer, methylcellulose, ethylcellulose, hydroxypropylmethylcellulose, polyethylene glycol, polyvinyl acetate, and partial kenne. Compound, gelatin, polyvinylpyrrolidone, starch, maleic anhydride-styrene copolymer, and the like. These can be used alone or in combination of two or more.

  As the polymerization initiator, a radical polymerization initiator is preferably used because it is advantageous for graft copolymerization. The type is not particularly limited. For example, lauroyl peroxide, t-butyl peroxypivalate, diisopropyl peroxydicarbonate, dioctyl peroxydicarbonate, t-butyl peroxyneodecanoate, α-cumyl peroxyneo Examples thereof include organic peroxides such as decanoate, azo compounds such as 2,2-azobisisobutyronitrile, 2,2-azobis-2,4-dimethylvaleronitrile, and the like.

  When graft copolymerizing a vinyl monomer containing vinyl chloride as a main component, a flocculant is added to the acrylic copolymer dispersion solution for the purpose of reducing the scale attached to the polymerization tank during the polymerization. Alternatively, a pH adjuster, an antioxidant and the like may be added as necessary.

  As the suspension polymerization method, for example, the following method can be used. That is, pure water, the acrylic copolymer dispersion solution, a dispersant, a polymerization initiator, and a water-soluble thickener and a polymerization degree regulator as necessary are charged into a reaction vessel equipped with a temperature controller and a stirrer. To do. After that, the air in the polymerization vessel is discharged with a vacuum pump, vinyl chloride is added under stirring conditions, and other vinyl monomers are added as required, and then the reaction vessel is heated with a jacket to graft copolymerize vinyl chloride. I do. At this time, the polymerization temperature is preferably 30 to 90 ° C. and the polymerization time 2 to 20 hours.

  In the suspension polymerization method described above, the temperature in the reaction vessel, that is, the polymerization temperature can be controlled by changing the jacket temperature.

  After completion of the reaction, a composite vinyl chloride resin can be obtained by removing unreacted vinyl chloride or the like to form a slurry, followed by dehydration drying.

  The composite vinyl chloride resin obtained by the above production method is excellent in impact resistance and mechanical strength because a part of polyvinyl chloride is directly bonded to the acrylic copolymer.

  In addition, the vinyl chloride resin used in the present invention is from the viewpoint of ensuring sufficient mechanical strength of the obtained vinyl chloride resin composition and rehabilitation pipe and ensuring moldability of the vinyl chloride resin composition. Those having an average degree of polymerization of 600 to 3000 are suitable, and those having an average degree of polymerization of 800 to 2000 are preferred. The average degree of polymerization refers to a resin obtained by dissolving vinyl chloride resin in tetrahydrofuran (THF), removing insoluble components by filtration, and then removing THF in the filtrate by drying. It means the average degree of polymerization measured according to the “vinyl resin test method”.

  The vinyl chloride resin may be a vinyl chloride homopolymer, or a copolymer of vinyl chloride and a monomer or polymer copolymerizable with vinyl chloride.

  Examples of the monomer or polymer copolymerizable with vinyl chloride are the same as the various monomers described above.

  As the vinyl chloride resin, any of conventionally known methods may be used, and examples thereof include suspension polymerization.

  The method for producing the vinyl chloride resin composition for rehabilitation pipe of the present invention is not particularly limited, and for example, it can be produced by using the above-described method for producing a composite vinyl chloride resin.

  In the vinyl chloride resin composition of the present invention, in the range not inhibiting the purpose of the present invention, if necessary, in addition to the essential component glass transition point, heat stabilizer, stabilization aid, lubricant, processing aid, One or more of various additives such as an antioxidant, a light stabilizer, and a pigment may be added. The addition method and order of addition of these additives are not particularly limited, and may be any method and any order.

  The heat stabilizer is not particularly limited. Organotin stabilizers such as tin laurate polymer, lead-based stabilizers such as lead stearate, dibasic lead phosphite, tribasic lead sulfate, calcium-zinc stabilizer, barium-zinc stabilizer, barium -A cadmium stabilizer etc. are mentioned. These may be used alone or in combination of two or more.

  The stabilizing aid is not particularly limited, and examples thereof include epoxidized soybean oil, epoxidized linseed bean oil, epoxidized tetrahydrophthalate, epoxidized polybutadiene, and phosphate ester. These may be used alone or in combination of two or more.

  The lubricant is not particularly limited, and examples thereof include montanic acid wax, paraffin wax, polyethylene wax, stearic acid, stearyl alcohol, and butyl stearate. These may be used alone or in combination of two or more.

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

  The antioxidant is not particularly limited, and examples thereof include those described above.

  The light stabilizer is not particularly limited, and examples thereof include ultraviolet absorbers such as salicylic acid esters, benzophenones, benzotriazoles, and cyanoacrylates, or hindered amine light stabilizers. These may be used alone or in combination of two or more.

  The pigment is not particularly limited, and examples thereof include organic pigments such as azo, phthalocyanine, selenium, and dye lakes, oxides, molybdenum chromate, sulfide / selenide, ferrocyanide, and the like. An inorganic pigment etc. are mentioned. These may be used alone or in combination of two or more.

  The method of mixing the above-described various compounding agents with the composite vinyl chloride resin is not particularly limited, and examples thereof include a method using hot blending and a method using cold blending.

  The vinyl chloride resin composition for rehabilitation pipes of the present invention can be used to form a molded body. The method for forming the molded body is not particularly limited, and examples thereof include an extrusion molding method, an injection molding method, a calendar molding method, and a press molding method.

  The obtained molded body ensures sufficient mechanical strength of the molded body, and also ensures the flow passage area of the tubular body even when the thickness of the tubular molded body is increased, and further the heat resistance of the molded body. From the viewpoint of ensuring the workability when applying the molded body to the existing pipe, the bending elastic modulus is 1470 MPa or more at 20 ° C., and at 50 ° C. It is preferable that it is 50-1470 MPa.

  The vinyl chloride resin rehabilitation pipe of the present invention comprises the vinyl chloride resin composition of the present invention and an existing pipe, and the vinyl chloride resin composition is configured in close contact with the inner surface of the existing pipe.

  The rehabilitation pipe is melt-kneaded with a vinyl chloride resin composition using an extruder, extruded, and formed into a tubular body having a desired cross-sectional shape. This tubular body is inserted into an existing pipe and heated. By doing so, it can be formed by closely contacting the inner surface of the existing pipe. The cross-sectional shape of the rehabilitating pipe is not particularly limited, and may be any shape that can be inserted into an existing pipe to be rehabilitated (repaired) and can be in close contact with the inner surface of the existing pipe by heating.

Examples of the vinyl chloride resin composition for rehabilitation pipes and vinyl chloride resin rehabilitation pipes according to the present invention will be described below, but are not limited to the following examples.
(Manufacture of acrylic copolymer)
(A1-A3, B1-B2)
The monomers for forming the core layer and the shell layer shown in Table 1 (hereinafter referred to as “core layer forming monomer” and “shell layer forming monomer”) are each given a predetermined amount of pure water (based on 100 parts by weight of the monomer). 60 parts by weight), a polyfunctional monomer (preferably 0.5 parts by weight per 100 parts by weight of each monomer) and polyoxyethylene distyrenated phenyl ether ammonium sulfate salt (emulsifying dispersant) are mixed and stirred. Each emulsifying monomer was prepared.
In Table 1, 2-EHA represents 2-ethylhexyl acrylate, n-BA represents n-butyl acrylate, and TMPTA represents trimethylolpropane triacrylate.

(Production of acrylic copolymer)
Pure water is put into a reactor equipped with a stirrer and a reflux condenser (preferably 160 parts by weight with respect to 100 parts by weight of all monomers), and oxygen in the container is replaced with nitrogen, and then the reaction temperature is 70 under stirring. The temperature was raised to ° C. After completion of the temperature increase, an initiator (0.5 parts by weight of ammonium persulfate is desirable with respect to 100 parts by weight of the total monomers) and 50% of the core layer forming monomer were charged all at once to initiate polymerization. Subsequently, the remainder of the core layer forming monomer was dropped. As soon as the dropping of the core layer forming monomer was completed, the shell layer forming monomer was sequentially dropped.
The dropping of all the emulsifying monomers was completed in 3 hours, and after a aging period of 1 hour, the polymerization was terminated, and an acrylic copolymer latex having a solid content concentration of about 30% by weight and a particle diameter of 0.1 μm ( (Hereinafter referred to as “latex”).

(Production of composite vinyl chloride resin by graft copolymerization)
In a polymerization vessel equipped with a stirrer and a jacket, 170 parts by weight of pure water, 9 parts by weight of the above acrylic copolymer latex, 5 parts by weight of a 3% aqueous solution of partially saponified polyvinyl alcohol (Kuraray Co., Ltd., Kuraray Poval L-8) 2.5 parts by weight of a 3% aqueous solution of hydroxypropylmethylcellulose (manufactured by Shin-Etsu Chemical Co., Ltd., Metrose 60SH50), 0.03 parts by weight of t-butyl peroxypivalate, and 9 parts by weight of an acrylic copolymer solid content On the other hand, aluminum ions were added all at once so that the aluminum ion was 3000 ppm. Thereafter, the air in the polymerization vessel was discharged with a vacuum pump, and 100 parts by weight of vinyl chloride was further added under stirring conditions. Graft polymerization was started at a polymerization temperature of 57.5 ° C. by controlling the jacket temperature.
Since the polymerization rate of the vinyl chloride monomer reached 80% when the pressure in the polymerization vessel dropped to 0.72 MPa, the completion of the reaction was confirmed. After adding an antifoaming agent (Toray Silicon Corporation SH5510, manufactured by Toray Industries, Inc.), the reaction was stopped. Thereafter, unreacted vinyl chloride monomer was removed and dehydrated and dried to obtain a vinyl chloride resin. The degree of polymerization of vinyl chloride in the composite vinyl chloride resin was about 1000.

(Preparation of vinyl chloride resin composition and rehabilitation pipe)
(Examples 1-9, Comparative Examples 1-12)
According to the composition shown in Table 2 or Table 3, ethylene-vinyl acetate copolymer (trade name “Elvalloy 742”, manufactured by Mitsui DuPont Chemical Co., Ltd.), urethane elastomer A based on 100 parts by weight of the obtained composite vinyl chloride resin. (Trade name “T-5275N”, manufactured by Dainippon Ink & Chemicals, Inc .: molecular weight 50000), urethane elastomer B (molecular weight 100000), acrylic modifier as impact modifier (trade name “KM357P” (Rohm and Haas) Polyester plasticizer A (trade name “S-2010 manufactured by Dick Bayer”: softening temperature 60 ° C., molecular weight> 3000), polyester plasticizer B (trade name “W3000” manufactured by Dick Bayer): softening temperature 80 ° C., molecular weight> 15000), low glass transition point and low melting point compound, ethylphthalylethyl glycate Trade name “# 10”, manufactured by Daihachi Chemical Co., Ltd.), adipic acid polyester (trade name “HA5”, manufactured by Kao), wollastonite (trade name: SH600, manufactured by Kinseimatic Co., Ltd .: (major axis / minor axis = 22) ), Mica (trade name: A300, manufactured by Otsuka Chemical Co., Ltd .: (major axis / minor axis = 35)), calcium carbonate (commercial name: Shiraka Hana CCR, manufactured by Shiroishi Kogyo Co., Ltd .: (major axis / minor axis = 1)) as a stabilizer 2 parts of organic tin stabilizer (trade name “ONZ-142F”, manufactured by Sankyo Co., Ltd.), 0.5 part of polyethylene wax lubricant (trade name “Hiwax220MP”, manufactured by Mitsui Petrochemical Co., Ltd.) as lubricant, as lubricant Stearic acid (trade name “S-30”, manufactured by Kao Co., Ltd.) 0.5 parts and processing aid “Metablene P501A” (manufactured by Mitsubishi Rayon Co., Ltd.) 3 parts by super mixer (100 L, manufactured by Kawata Co., Ltd.) Stir and mix As a result, a vinyl chloride resin composition was obtained.

  The vinyl chloride resin composition obtained above is supplied to a biaxial counter-rotating extruder (trade name “SLM-50”, manufactured by Nagata Seisakusho Co., Ltd.) having a diameter of 50 mm, and a vinyl chloride resin molding having an outer diameter of 50 mm is performed. Got the body. The obtained molded body was allowed to stand in a gear oven heated to 80 ° C. for 20 minutes, and then the rehabilitation pipe cross section was made into a quadruple shape, and the temperature of the molded body was kept at 20 ° C. while maintaining this shape. A rehabilitation tube was prepared by cooling to the end.

  The performance (bending elastic modulus, impact resistance, workability) of the rehabilitated pipe produced using the vinyl chloride resin composition obtained in Table 2 was evaluated by the following methods. The results are shown in Table 2.

  (1) Flexural modulus: The flexural modulus of the rehabilitated pipe was measured according to JIS K-7203 “Bending test method for hard plastic”. The measurement was performed in an atmosphere at 20 ° C. and 50 ° C.

  (2) Impact resistance: Based on JIS K-7111 “Charpy impact test method for hard plastic”, the Charpy impact value of the rehabilitated pipe was measured using a notched (notched) test piece. The measurement was performed in an atmosphere at 0 ° C.

(3) Workability: Insert the rehabilitation pipe into a steel pipe with an inner diameter of 50 mm, blow 90 ° C hot air from one end of the rehabilitation pipe into the rehabilitation pipe for 10 minutes, and attach the rehabilitation pipe to the inner surface of the steel pipe. It was. Subsequently, after cooling by blowing air at 20 ° C. for 30 minutes, the close contact state between the steel pipe and the renovated pipe was visually observed, and the workability was evaluated according to the following criteria.
[Criteria]
○ ... The rehabilitated pipe was in close contact with the steel pipe. × ... The rehabilitated pipe was not partially or fully in close contact with the steel pipe. Also, the vinyl chloride resin composition obtained in Table 3 About, the elasticity modulus according to temperature was measured. The results are shown in FIGS.

Further, among the vinyl chloride resin compositions obtained in Table 3, the pulling force and the degree of diameter expansion were evaluated when a rehabilitated tube was prepared using the vinyl chloride resin compositions of Example 6 and Comparative Example 10. .
All of these evaluations are evaluations when applied to a 400 omega-shaped pipe.

  As a result, in Example 6, the pulling force was 1.2 tons, whereas in Comparative Example 10, it was 2.5 tons. Further, in the diameter expansion test in the 0 fume pipe having a diameter of 2400 mm and a diameter of 40, in Example 6, the diameter could be normally expanded in a preheating time of 20 minutes, whereas in Comparative Example 11, the preheating time was 40 minutes. Met.

(Preparation of vinyl chloride resin composition and rehabilitation pipe)
(Examples 10-13, Comparative Examples 13-17)
For vinyl chloride resin (trade name “TS1000R”, manufactured by Tokuyama Sekisui Kogyo Co., Ltd.), according to the composition of Table 4, an ethylene-vinyl acetate copolymer (trade name “Elvalloy 742”, manufactured by Mitsui DuPont Chemical Co., Ltd.), urethane type Elastomer A (trade name “T-5275N”, manufactured by Dainippon Ink & Chemicals, Inc.), low glass transition point and low melting point compound include ethyl phthalyl ethyl glycate (trade name “# 10”, manufactured by Daihachi Chemical Co., Ltd.) ), Adipic acid polyester (trade name “HA5”, manufactured by Kao), wollastonite (trade name: SH600, manufactured by Kinseimatic Co., Ltd.), mica (trade name: A300, manufactured by Otsuka Chemical Co., Ltd.), MBS (impact modifier) Product name “B564” (manufactured by Kaneka)), chlorinated polyethylene (product name “JMR135C” (manufactured by Daiso), acrylic modifier (product name “KM357”) (Rohm and Haas), 2 parts of organic tin stabilizer, 0.5 part of polyethylene wax lubricant, 0.5 part of stearic acid and 3 parts of processing aid in a super mixer (100 L, manufactured by Kawata) By stirring and mixing, a vinyl chloride resin composition was obtained.

The vinyl chloride resin composition obtained above was supplied to a biaxial different-direction rotary extruder (trade name “SLM-50”, manufactured by Nagata Seisakusho Co., Ltd.) having a diameter of 50 mm. Were prepared and evaluated in the same manner.
The results are shown in Table 4.

  The vinyl chloride resin composition of the present invention can be used not only for the production of rehabilitation pipes but also for the production of tubular bodies used in various applications. Furthermore, it can be used not only in the production of a tubular body but also in any molded body obtained using a vinyl chloride resin.

It is a graph which shows the elasticity modulus according to temperature of the rehabilitation pipe | tube created in the Example of the vinyl chloride-type resin composition of this invention. It is the graph which expanded the scale of the principal part of the graph of FIG.

Claims (10)

For 100 parts by weight of a composite vinyl chloride resin obtained by graft copolymerization of 70 to 99% by weight of a vinyl monomer having vinyl chloride as a main component with 1 to 30% by weight of an acrylic copolymer,
10 to 30 parts by weight of a thermoplastic elastomer that is compatible with the composite vinyl chloride resin,
A vinyl chloride resin composition for rehabilitated pipes, wherein 1 to 10 parts by weight of a needle-like or plate-like inorganic substance is added.   The vinyl chloride resin composition for rehabilitation pipes according to claim 1, further comprising 3 to 10 parts by weight of an impact modifier. For 100 parts by weight of vinyl chloride resin having an average degree of polymerization of 600 to 3000,
10 to 30 parts by weight of a thermoplastic elastomer that is compatible with the vinyl chloride resin,
1 to 10 parts by weight of a needle-like or plate-like inorganic substance,
A vinyl chloride resin composition for rehabilitated pipes, wherein an impact modifier is added in an amount of 3 to 30 parts by weight.   The low glass transition point or low melting point compound A (excluding the thermoplastic elastomer) is further added in an amount of 10 to 30 parts by weight in total with the thermoplastic elastomer. Vinyl chloride resin composition for rehabilitation pipes.   The acrylic copolymer has a glass transition temperature of −140 ° C. or higher and lower than 0 ° C., 100 parts by weight of a radically polymerizable monomer having at least one (meth) acrylate as a main component, and 0.1 to 0.1% of a multifunctional monomer. The vinyl chloride resin composition for rehabilitation pipes according to any one of claims 1 to 3, which is an acrylic copolymer comprising 10 parts by weight.   The acrylic copolymer is a copolymer 40 of 100 parts by weight of a radically polymerizable monomer and 0.1 to 1 part by weight of a polyfunctional monomer having a glass transition temperature of -140 ° C or higher and lower than -60 ° C. 100 wt parts of a radically polymerizable monomer mainly composed of (meth) acrylate having a glass transition temperature of -55 ° C or higher and lower than 0 ° C and a polyfunctional monomer of 1.5 to 10 wt% The vinyl chloride resin composition for rehabilitation pipes according to any one of claims 1 to 5, comprising a core-shell structure obtained by graft copolymerizing 10 to 60% by weight of a mixed monomer of 10 parts by weight.   The chloride elastic body for rehabilitation pipes according to any one of claims 1 to 5, wherein a bending elastic modulus of a molded body comprising the vinyl chloride resin composition for rehabilitation pipes is 1470 Mpa or more at 20 ° C and 50 to 1470 Mpa at 50 ° C. Vinyl resin composition.   The vinyl chloride resin composition for rehabilitation pipes according to any one of claims 1 to 7, wherein the needle-like or plate-like inorganic substance has an aspect ratio of 10 or more and comprises a metal composite oxide.   The thermoplastic elastomer compatible with the composite vinyl chloride resin includes a urethane elastomer having a molecular weight of 1,000 to 60,000 or an ester plasticizer having a molecular weight of 20000 or less and an ester plasticizer having a molecular weight of 20000 or less. The vinyl chloride resin composition for rehabilitation pipes described in 1. A vinyl chloride resin composition for rehabilitation pipes according to any one of claims 1 to 9, and an existing pipe.
A vinyl chloride resin rehabilitating tube, wherein the vinyl chloride resin composition for rehabilitating tube is inserted into an existing tube and heated to adhere to the inner surface of the existing tube.

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