JP7103784B2 - Pipe material and piping - Google Patents

Description

The present invention relates to pipe materials and pipes.

In a building, in the event of an emergency such as a fire, one of the causes of the fire moving from the area where the fire originated to another area is the existence of pipes such as drainage pipes installed in the building.

Conventionally, a piping material having fire resistance has been proposed in order to minimize the transfer of fire through the piping. Furthermore, in recent years, there has been a proposal to prevent the transfer of fire through the pipe by constructing the pipe with a material as described in Patent Document 1 so that the pipe material expands due to the heat of the fire and blocks the pipe itself. It has been done. As such a pipe or a pipe material, Patent Document 2 describes a pipe material containing thermally expandable graphite.

In order to more reliably prevent the transfer of fire through the pipe, it is preferable to use a pipe material having higher thermal expansion. Therefore, it is conceivable to add a large amount of thermally expandable graphite to the piping material disclosed in Patent Document 2 to obtain a piping material having higher thermal expansion. However, if the content of the heat-expandable graphite in the piping material is excessive, there is a concern that the strength of the piping will be insufficient.

As described above, the relationship between the thermal expandability and the strength is, so to speak, a trade-off relationship, and it is difficult to obtain a piping material having both properties at a high level.

Japanese Unexamined Patent Publication No. 03-41161 JP-A-2009-74689

In view of the above circumstances, an object of the present invention is to provide a pipe material and a pipe having high thermal expansion property and sufficient strength.

As a result of diligent research to achieve the above object, the present inventors impose a particulate thermal-expandable graphite and a particulate flame-retardant, and set the ratio of the average particle diameters of both within a predetermined range. As a result, it was found that a pipe material having sufficient strength while having high expandability can be obtained. The present inventors have further studied based on such findings, and have completed the present invention.

That is, the present invention provides the following pipe materials and pipes.
Item 1.
It contains a polyvinyl chloride resin, 10 to 20 parts by mass of particulate thermoexpandable graphite with respect to 100 parts by mass of the polyvinyl chloride resin, and a particulate flame retardant.
The ratio (B / A) of the average particle size (A) of the particulate thermoexpandable graphite to the average particle size (B) of the particulate flame retardant is 0.1 to 0.7. , Pipe material.
Item 2.
Item 2. The tube material according to Item 1, wherein the average particle size (A) of the particulate thermal expandable graphite is 110 to 1000 μm.
Item 3.
A pipe made of the pipe material according to Item 1 or 2.

The pipe material and piping of the present invention have sufficient strength while having high thermal expansion.

<1. Tube material>
The pipe material of the present invention contains a polyvinyl chloride-based resin, 10 to 20 parts by mass of particulate thermoexpandable graphite with respect to 100 parts by mass of the polyvinyl chloride-based resin, and a particulate flame retardant, and the particulate thermal expansion. The ratio (B / A) of the average particle size (A) of the sex graphite to the average particles (B) of the particulate flame retardant is 0.1 to 0.7.

Polyvinyl chloride-based resin Examples of the polyvinyl chloride-based resin include a polyvinyl chloride homopolymer; a copolymer of a vinyl chloride monomer and a monomer having an unsaturated bond capable of copolymerizing with the vinyl chloride monomer; vinyl chloride. Examples thereof include graft copolymers obtained by graft-copolymerizing vinyl chloride to other (co) polymers, and these may be used alone or in combination of two or more. Further, the polyvinyl chloride resin may be chlorinated if necessary.

The monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer is not particularly limited, and for example, α-olefins such as ethylene, propylene and butylene; vinyl esters such as vinyl acetate and vinyl propionate; butyl Vinyl ethers such as vinyl ether and cetyl vinyl ether; (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl acrylate; aromatic vinyls such as styrene and α-methylstyrene; N-phenylmaleimide , N-substituted maleimides such as N-cyclohexyl maleimide, etc., and these may be used alone or in combination of two or more.

The (co) copolymer obtained by graft-copolymerizing vinyl chloride is not particularly limited as long as it is graft-copolymerized with vinyl chloride, and is, for example, an ethylene-vinyl acetate copolymer or ethylene-vinyl acetate-. Carbon monoxide copolymer, ethylene-ethyl acrylate copolymer, ethylene-butyl acrylate-carbon monoxide copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, acrylonitrile-butadiene copolymer, polyurethane , Chlorinated polyethylene, chlorinated polypropylene and the like, and these may be used alone or in combination of two or more.

The average degree of polymerization of the polyvinyl chloride resin is not particularly limited, but if it is small, the physical properties of the molded product are deteriorated, and if it is large, the melt viscosity becomes high and molding becomes difficult. Preferably, 600 to 1400 is particularly preferable. The average degree of polymerization is defined by using a resin obtained by dissolving a composite vinyl chloride resin in tetrahydrofuran (THF), removing insoluble components by filtration, and then drying and removing THF in the filtrate as a sample. It means the average degree of polymerization measured according to -6721 "Vinyl chloride resin test method".

The polymerization method of the polyvinyl chloride-based resin is not particularly limited, and any conventionally known polymerization method may be adopted, and examples thereof include a bulk polymerization method, a solution polymerization method, an emulsion polymerization method, and a suspension polymerization method. Be done.

The chlorination method for the polyvinyl chloride resin is not particularly limited, and a conventionally known chlorination method may be adopted, and examples thereof include a thermal chlorination method and a photochlorination method.

Any of the above polyvinyl chloride-based resins may be crosslinked or modified before use as long as the fire resistance performance of the resin composition is not impaired. In this case, a resin that has been crosslinked or modified in advance may be used, or may be crosslinked or modified at the same time when the additive or the like is added, or may be crosslinked or modified after the above components are added to the resin. .. The method for cross-linking the above resin is also not particularly limited, and a usual cross-linking method for a polyvinyl chloride resin, for example, various cross-linking agents, cross-linking using a peroxide, cross-linking by electron beam irradiation, or a water cross-linking material is used. Examples of the method used.

The heat-expandable graphite contained in the particulate heat-expandable graphite tube material is a particle-like heat-expandable graphite. As the heat-expandable graphite, known ones can be widely used, and there is no particular limitation. Specific examples thereof include monomethylamine, dimethylamine, trimethylamine, ethylamine, propylamine and butylamine. Examples of the alkali metal compound and alkaline earth metal compound include hydroxides such as potassium, sodium, calcium, barium and magnesium, oxides, carbonates, sulfates and organic acid salts. These may be used alone or in combination of two or more.

The content of the particulate thermal expandable graphite in the tube material is 10 parts by mass or more, preferably 10.5 parts by mass or more, with respect to 100 parts by mass of the polyvinyl chloride resin. When the content of the particulate heat-expandable graphite is less than 10 parts by mass, the heat-expandability of the tube material becomes insufficient. On the other hand, the content of the particulate thermal expandable graphite in the tube material is 20 parts by mass or less, preferably 16 parts by mass or less, with respect to 100 parts by mass of the polyvinyl chloride resin. When the content of the particulate thermal expandable graphite is more than 20 parts by mass, the strength of the tube material becomes insufficient.

The average particle size (A) of the particulate heat-expandable graphite is preferably 110 μm or more, more preferably 120 μm or more, and further preferably 200 μm or more. When the average particle size (A) is 110 μm or more, the thermal expandability of the obtained tube can be improved. On the other hand, the average particle size (A) of the particulate thermally expandable graphite is preferably 1000 μm or less, and more preferably 400 μm or less. When the average particle size (A) is 1000 μm or less, the fire resistance and strength of the pipe material are improved.

In the present specification, the average particle size (A) of the particulate heat-expandable graphite shall be calculated as follows.
100 g of particulate thermal expandable graphite is meshed with a test sieve based on JIS Z8801-1, and the average particle size (A) is the size of the mesh opening of the test sieve (μm) × the weight of the mesh angstrom (g). / The total weight (g).

Particulate flame retardant As the flame retardant, a particulate flame retardant is used. The flame retardant processed into particles is not particularly limited, and a known flame retardant can be widely used.

Specific examples of the flame retardant include hydroxides such as aluminum hydroxide and magnesium hydroxide, hydrotalcite, antimony dioxide, antimony trioxide, antimony oxide such as antimony pentoxide, molybdenum trioxide, and molybdenum disulfide. Molybdenum compounds such as ammonium molybdate, bromine compounds such as tetrabromobisphenol A, tetrabromuethane, tetrabromuethane, tetrabromuethane, phosphorus compounds such as triphenyl phosphate and ammonium polyphosphate, calcium borate, hoe Examples include zinc acid acid, calcium phosphate, zinc phosphate and the like. These may be used alone or in combination of two or more.

The average particle size (B) of the particulate flame retardant is preferably 40 μm or more, and more preferably 60 μm or more. When the average particle size (B) is 40 μm or more, the dispersibility of the particulate flame retardant is improved when the tube material is manufactured. On the other hand, the average particle size (B) of the particulate flame retardant is preferably 120 μm or less, and more preferably 90 μm or less. When the average particle size (B) is 120 μm or less, the dispersibility of the particulate flame retardant is improved when the pipe material is manufactured.

In the present specification, the average particle size (B) of the particulate flame retardant shall be calculated as follows.
100 g of particulate flame retardant is meshed with a test sieve based on JIS Z8801-1, and the average particle size (B) is the size of the opening of the test sieve (μm) x the weight of the mesh-on (g) / overall. Weight (g).

The ratio (B / A) of the average particle size (A) of the particulate thermoexpandable graphite and the average particle size (B) of the particulate flame retardant is 0.1 or more, more preferably 0.1 or more. , 0.15 or more. If the ratio (B / A) is less than 0.1, the strength of the pipe material becomes insufficient. On the other hand, the ratio (B / A) is 0.7 or less, more preferably 0.4 or less. When the ratio (B / A) is larger than 0.7, the thermal expansion property of the pipe material becomes insufficient.

The content of the particulate flame retardant in the tube material is preferably 0.5 to 10 parts by mass and more preferably 1 to 6 parts by mass with respect to 100 parts by mass of the above-mentioned polyvinyl chloride resin. preferable. By having such a configuration, it is possible to obtain a pipe material having sufficient strength and also having fire resistance.

Additives In addition, the pipe materials of the present invention include inorganic fillers, lubricants, processing aids, impact modifiers, heat improvers, antioxidants, light stabilizers, and UV absorbers, as long as their physical properties are not impaired. , Pigments, plasticizers, thermoplastic elastomers and other additives may be added.

As the inorganic filler, known ones can be widely used, and there is no particular limitation. Specifically, silica, diatomaceous earth, alumina, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, basic carbon dioxide. Magnesium, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dawn night, hydrotalcite, calcium sulfate, barium sulfate, gypsum fiber, calcium silicate, talc, clay, mica, montmorillonite, bentonite, active white clay, sepiolite, imogolite , Serisite, glass fiber, glass beads, silica-based balun, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon balun, charcoal powder, various metal powders, potassium titanate, magnesium sulfate "MOS" , Lead zircate titanate, aluminum borate, molybdenum sulfide, silicon carbide, stainless fiber, zinc borate, various magnetic powders, slag fibers, fly-a-w, and dehydrated sludge. ..

As the lubricant, known ones can be widely used, and there is no particular limitation. Examples of the lubricant include an internal lubricant and an external lubricant. The internal lubricant is used for the purpose of lowering the flow viscosity of the molten resin during molding and preventing frictional heat generation. The internal lubricant is not particularly limited, and for example, one or more selected from the group consisting of butyl stearate, lauryl alcohol, stearyl alcohol, epoxy soybean oil, glycerin monostearate, stearic acid, and bisamide may be used. can. Further, the external lubricant is used for the purpose of enhancing the sliding effect between the molten resin and the metal surface during the molding process. The external lubricant is not particularly limited, and for example, one or more selected from the group consisting of paraffin wax, polyolefin wax, ester wax, and montanic acid wax can be used.

As the processing aid, known ones can be widely used, and there is no particular limitation. 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 million can be mentioned. The acrylic processing aid is not particularly limited, and examples thereof include an n-butyl acrylate-methyl methacrylate copolymer and a 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymer. These may be used alone or in combination of two or more.

As the impact modifier, known ones can be widely used, and there is no particular limitation. For example, one or more selected from the group consisting of methyl methacrylate-butadiene-styrene copolymer (MBS), chlorinated polyethylene, acrylic rubber and the like can be used.

As the heat resistance improver, known ones can be widely used, and there is no particular limitation. For example, α-methylstyrene type resin, N-phenylmaleimide type resin and the like can be used.

The antioxidant is not particularly limited, and known ones can be widely used. For example, a phenolic antioxidant and the like can be mentioned.

The light stabilizer is not particularly limited, and known ones can be widely used. For example, a light stabilizer such as a hindered amine type may be used.

The ultraviolet absorber is not particularly limited, and known ones can be widely used. Examples thereof include ultraviolet absorbers such as salicylic acid ester type, benzophenone type, benzotriazole type and cyanoacrylate type. These may be used alone or in combination of two or more.

The pigment is not particularly limited, and known pigments can be widely used. For example, organic pigments such as azo-based, phthalocyanine-based, slene-based, and dye lake-based; inorganic pigments such as oxide-based, molybdenum chromate-based, sulfide / selenium-based, and ferrocyanine-based pigments can be mentioned. These may be used alone or in combination of two or more.

Further, a plasticizer may be added to the polyvinyl chloride resin. The plasticizer is not particularly limited, and known ones can be widely used. For example, one or more selected from the group consisting of dibutyl phthalate, di2-ethylhexyl phthalate, and di-2-ethylhexyl adipate can be used.

The thermoplastic elastomer is not particularly limited, and known ones can be widely used. For example, acrylic nitrile-butadiene copolymer (NBR), ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl acetate-carbon monoxide copolymer (EVACO), vinyl chloride-vinyl acetate copolymer and vinyl chloride. -Selected from the group consisting of vinyl chloride-based thermoplastic elastomers such as vinylidene chloride copolymers, styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, and polyamide-based thermoplastic elastomers. You can use more than one type.

As a method of mixing the above-mentioned particulate thermal expandable graphite, the particulate flame retardant, and the additive with the polyvinyl chloride resin, a known method can be widely adopted. Specific examples thereof include a hot blending method and a cold blending method.

<2. Plumbing>
The pipe material of the present invention as described above has sufficient strength while having high thermal expansion property, and can be suitably used for pipes (drainage pipes, ducts, electric wire pipes, etc.) of buildings. Further, the pipe material of the present invention can be suitably used not only as a constituent material of a pipe main body but also as a constituent material of a pipe joint.

Although the embodiments of the present invention have been described above, the present invention is not limited to these examples, and it goes without saying that the present invention can be implemented in various forms without departing from the gist of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail based on Examples, but the present invention is not limited thereto.

(Examples and comparative examples)
Based on the formulation shown in Table 1 below, roll knead with an 8-inch mixing roll (manufactured by Yasuda Seiki Seisakusho) at 190 ° C for 3 minutes, and press-molded with a press machine at 200 ° C (manufactured by Toho Machinery Co., Ltd.) for 4 minutes. Test pieces of each Example and Comparative Example having a thickness of 3 mm were prepared.

Tensile strength evaluation test The tensile yield strength of each example and comparative example was measured at 5 mm / min according to the tensile test method (JIS K7113) of plastics. The measurement atmosphere at this time was 23 ° C. The tensile yield strength f (MPa) is calculated by the following formula, where the maximum load until the test piece breaks is P (N) and the cross-sectional area of the test piece is S (mm ² ). If is 42 (MPa) or more, it is judged that there is no practical problem.
Tensile yield strength: f = P / S

Expansion Magnification Evaluation Test A plate-shaped test piece was cut out in a rectangular cuboid shape by a roll press, and the thickness, length, and width were measured with a caliper. Then, the test pieces of each Example and Comparative Example were placed in an electric furnace heated to 950 ° C. for 4 minutes to be expanded. After that, it was taken out from an electric furnace and allowed to cool at room temperature. The thickness, length, and width of the cooled expanded test piece are measured with a caliper, and the expansion factor R is calculated by the following formula. It was judged.
Expansion ratio: R = (a ₁ b ₁ c ₁ ) / (a ₀ b ₀ c ₀ )
a ₀ : Specimen thickness (mm) before expansion
b ₀ : Vertical length of test piece before expansion (mm)
c ₀ : Specimen lateral length (mm) before expansion
a ₁ : Specimen thickness (mm) after expansion
b ₁ : Vertical length of the test piece after expansion (mm)
c ₁ : Horizontal length of test piece after expansion (mm)

As shown in Table 1 below, it was confirmed that the test pieces of each example had excellent properties in terms of both strength and expandability. On the other hand, it was confirmed that the test pieces of Comparative Examples 1 and 2 were practically insufficient in either the strength or the expandability property.

Claims (4)

It contains a polyvinyl chloride resin, 10 to 20 parts by mass of particulate thermoexpandable graphite with respect to 100 parts by mass of the polyvinyl chloride resin, and a particulate flame retardant.
The ratio (B / A) of the average particle size (A) of the particulate thermoexpandable graphite to the average particle size (B) of the particulate flame retardant is 0.1 to 0.7 .
A pipe material containing 0.5 to 10 parts by mass of the particulate flame retardant with respect to 100 parts by mass of the polyvinyl chloride resin . The tube material according to claim 1, wherein the average particle size (A) of the particulate thermal expandable graphite is 110 to 1000 μm. The pipe material according to claim 1 or 2 , wherein the particulate flame retardant is zinc phosphate. A pipe made of the pipe material according to any one of claims 1 to 3 .