JP2021109313A - Joint structure of resin pipe and joint - Google Patents

Abstract

To provide a joint structure of a resin pipe and a joint capable of improving repetitive fatigue characteristics at an atmospheric temperature and at a high temperature in a joint portion between the resin pipe and the joint and therefore capable of improving joint reliability.SOLUTION: In a joint structure 4 of a resin pipe 1 and a joint 2, the resin pipe 1 includes a resin pipe body 11 and a first modified layer 12 arranged on an outer surface of the resin pipe body 11, the joint 2 includes a joint main body 21 and a second modified layer 22 arranged on an inner surface of the joint main body, and each of the first modified layer 12 and the second modified layer 22 includes a side-chain crystalline block copolymer. In the joint portion between the resin pipe 1 and the joint 2, the first modified layer 12, an adhesion layer 3, and the second modified layer 22 are arranged in this order.SELECTED DRAWING: Figure 1

Description

The present invention relates to a joint structure of a resin pipe and a joint.

Conventionally, as a method of joining a vinyl chloride resin pipe and a joint, a method of applying a solution containing a solvent, a vinyl chloride monomer and the like to the outer surface of the vinyl chloride resin pipe and the inner surface of the joint and then crimping the pipe has been performed.

On the other hand, since the resin pipe containing the olefin resin has chemical resistance, it is difficult to crimp the resin pipe and the joint with the solution containing the solvent as described above. Therefore, conventionally, as a joining method between the joint and the resin pipe containing the olefin resin, a fusion method such as an EF joining method and a butt joining method has been performed. Further, since it is difficult to join a resin pipe containing a cross-linked olefin resin such as a cross-linked polyethylene resin by fusion, a joint having a complicated structure is used to join the resin pipe and the joint. ..

Further, as described in Patent Document 1 below, a method of adhering a polyethylene resin tube with an adhesive is also known. In Patent Document 1 below, polyethylene pipes are attached to each other, an adhesive is applied to at least one of the attached end face and the attached outer peripheral surface, and a halved cover is applied to the upper part of the applied adhesive. A polyethylene tube bonding method for covering and adhering a material is disclosed.

Further, in Patent Document 2 below, a step of contacting a copolymer solution containing a side chain crystalline block copolymer and a polypropylene resin molded product at a temperature of the copolymer solution of 40 ° C. to 120 ° C. A method for modifying a polypropylene resin molded product having the above is disclosed. In Patent Document 2, a T-type peeling test and a tensile shear test were carried out using a test piece in which modified film-shaped polypropylene resin molded bodies (modified PP films) were bonded to each other with an adhesive. It is described that the adhesive strength is improved as compared with the test piece in which poor quality PP films are bonded to each other with an adhesive.

JP-A-2007-090673 Japanese Unexamined Patent Publication No. 2019-137779

In the method of joining the resin pipe and the joint by fusion such as the EF joining method and the butt joining method, it is necessary to use a dedicated device for fusion at the construction site or to use a joint having a complicated structure. It is inferior in workability. Further, in this method, it is necessary to use an expensive joint, which is inferior in economy.

Further, it is difficult to sufficiently increase the adhesive force between the resin pipe and the joint by the conventional method using an adhesive as described in Patent Document 1 above.

By the way, not only low-temperature to normal-temperature liquid but also high-temperature liquid is repeatedly passed through the inside of the pipe in which the resin pipe and the joint are joined. Therefore, when the repeated fatigue characteristics of the joint portion between the resin pipe and the joint are low, it is difficult to sufficiently improve the joint reliability.

In addition, the above-mentioned Patent Document 2 states that the adhesive strength of the test piece obtained by adhering the modified polypropylene resin molded bodies (film-shaped modified PP film) to each other with an adhesive is improved under specific test conditions. Is only described. Further, Patent Document 2 merely describes a sheet, a plate, a fiber, and a porous material as the shape of the modified polypropylene resin.

As described above, conventionally, when the resin pipe and the joint are joined by a method different from the fusion, a method for sufficiently improving the joining reliability has not been sufficiently studied.

An object of the present invention is to provide a joint structure between a resin pipe and a joint, which can enhance the repeated fatigue characteristics at room temperature and high temperature at the joint portion between the resin pipe and the joint, and therefore can improve the joint reliability. To provide.

According to a broad aspect of the present invention, it is a joint structure of a resin pipe and a joint, and the resin pipe is a first modified layer arranged on a resin pipe main body and an outer surface of the resin pipe main body. The joint includes a joint body and a second modified layer arranged on the inner surface of the joint body, and the first modified layer and the second modified layer are respectively. , The first modified layer, the adhesive layer, and the second modified layer are arranged in this order at the joint portion between the resin pipe and the joint, which contains a side chain crystalline block copolymer. Provided is a joint structure of a resin pipe and a joint having the above-mentioned structure.

According to a broad aspect of the present invention, it is a joint structure of a resin pipe and a joint, and the resin pipe is a first modified layer arranged on a resin pipe main body and an inner surface of the resin pipe main body. The joint includes a joint body and a second modified layer arranged on the outer surface of the joint body, and the first modified layer and the second modified layer are respectively. , The second modified layer, the adhesive layer, and the first modified layer are arranged in this order at the joint portion between the resin pipe and the joint, which contains a side chain crystalline block copolymer. Provided is a joint structure of a resin pipe and a joint having the above-mentioned structure.

In a specific aspect of the joint structure of the resin pipe and the joint according to the present invention, the resin pipe body contains an olefin resin or a fluorine resin, and the joint body contains an olefin resin or a fluorine resin. ..

In the joint structure of the resin pipe and the joint according to the present invention, the resin pipe includes a resin pipe main body and a first modified layer arranged on the outer surface of the resin pipe main body, and the joint A joint body and a second modified layer arranged on the inner surface of the joint body are provided, and the first modified layer and the second modified layer are both side chain crystalline blocks. Contains polymer. In the joint structure of the resin pipe and the joint according to the present invention, the first modified layer, the adhesive layer, and the second modified layer are formed at the joint portion between the resin pipe and the joint. It has a structure arranged in this order. Since the joint structure of the resin pipe and the joint according to the present invention is provided with the above configuration, it is possible to enhance the repetitive fatigue characteristics at room temperature and high temperature at the joint portion between the resin pipe and the joint. , The joint reliability can be improved.

In the joint structure of the resin pipe and the joint according to the present invention, the resin pipe includes a resin pipe main body and a first modified layer arranged on the inner surface of the resin pipe main body, and the joint A joint body and a second modified layer arranged on the outer surface of the joint body are provided, and the first modified layer and the second modified layer are both side chain crystalline blocks. Contains polymer. In the joint structure of the resin pipe and the joint according to the present invention, the second modified layer, the adhesive layer, and the first modified layer are formed at the joint portion between the resin pipe and the joint. It has a structure arranged in this order. Since the joint structure of the resin pipe and the joint according to the present invention is provided with the above configuration, it is possible to enhance the repetitive fatigue characteristics at room temperature and high temperature at the joint portion between the resin pipe and the joint. , The joint reliability can be improved.

FIG. 1 is a cross-sectional view schematically showing a joint structure of a resin pipe and a joint according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing a resin pipe used in the joint structure shown in FIG. FIG. 3 is a cross-sectional view schematically showing a joint used in the joint structure shown in FIG. FIG. 4 is a cross-sectional view schematically showing a joint structure of a resin pipe and a joint according to a second embodiment of the present invention. FIG. 5 is a cross-sectional view schematically showing the resin pipe used in the joint structure shown in FIG. FIG. 6 is a cross-sectional view schematically showing a joint used in the joint structure shown in FIG. FIG. 7A is a diagram showing the shape of the sample used in the evaluation of the examples, and FIG. 7B is a diagram showing the shape of the dumbbell-shaped test piece used in the evaluation of the examples. be. FIG. 8 (a) is the result of the repeated fatigue characteristic at room temperature (23 ° C.) of Example 1, and FIG. 8 (b) is the result of the repeated fatigue characteristic at high temperature (90 ° C.) of Example 1. be. FIG. 9A shows the result of the repeated fatigue characteristic of Comparative Example 1 at room temperature (23 ° C.), and FIG. 9B shows the result of the repeated fatigue characteristic of Comparative Example 1 at a high temperature (90 ° C.). be.

Hereinafter, the present invention will be described in detail.

In the joint structure of the resin pipe and the joint according to the present invention, the resin pipe includes a resin pipe main body and a first modified layer arranged on the outer surface of the resin pipe main body, and the joint A joint body and a second modified layer arranged on the inner surface of the joint body are provided, and the first modified layer and the second modified layer are both side chain crystalline blocks. Contains polymer. In the joint structure of the resin pipe and the joint according to the present invention, the first modified layer, the adhesive layer, and the second modified layer are formed at the joint portion between the resin pipe and the joint. It has a structure arranged in this order. The first modified layer, the adhesive layer, and the second modified layer are arranged in this order from the center of the bonded structure toward the outer side in the radial direction.

In the joint structure of the resin pipe and the joint according to the present invention, the resin pipe includes a resin pipe main body and a first modified layer arranged on the inner surface of the resin pipe main body, and the joint A joint body and a second modified layer arranged on the outer surface of the joint body are provided, and the first modified layer and the second modified layer are both side chain crystalline blocks. Contains polymer. In the joint structure of the resin pipe and the joint according to the present invention, the second modified layer, the adhesive layer, and the first modified layer are formed at the joint portion between the resin pipe and the joint. It has a structure arranged in this order. The second modified layer, the adhesive layer, and the first modified layer are arranged in this order from the center of the bonded structure toward the outer side in the radial direction.

Since the joint structure of the resin pipe and the joint according to the present invention is provided with the above configuration, it is possible to enhance the repetitive fatigue characteristics at room temperature and high temperature at the joint portion between the resin pipe and the joint. , The joint reliability can be improved. In the joint structure of the resin pipe and the joint according to the present invention, for example, the repetitive fatigue characteristics at 23 ° C. and the repetitive fatigue characteristics at 90 ° C. can be enhanced.

In general, it is difficult to improve the joining reliability by adhering the resin pipe and the joint with an adhesive. In particular, when the resin in the resin pipe is an olefin resin such as polyethylene resin or polypropylene resin or a fluorine-based resin, it is difficult to bond the resin pipe and the joint with an adhesive.

On the other hand, in the present invention, since the resin pipe provided with the specific first modified layer and the joint provided with the specific second modified layer are used, the first modification The adhesive strength between the quality layer and the adhesive layer and the adhesive strength between the second modified layer and the adhesive layer can be considerably increased, and the joint reliability can be improved at the joint portion between the resin pipe and the joint. ..

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a cross-sectional view schematically showing an example of a resin tube used in the present invention. FIG. 2 is a cross-sectional view schematically showing a resin pipe used in the joint structure shown in FIG.

The resin tube 1 shown in FIG. 2 includes a resin tube main body 11 and a first modified layer 12. The first modified layer 12 is arranged on the outer surface 11a of the resin tube main body 11. The first modified layer 12 is arranged on the entire outer surface 11a of the resin tube main body 11. The first modified layer 12 reaches both ends of the resin tube main body 11. The first modified layer 12 is the outermost layer of the resin pipe 1. The first modified layer 12 contains a side chain crystalline block copolymer.

FIG. 3 is a cross-sectional view schematically showing an example of a joint used in the present invention. FIG. 3 is a cross-sectional view schematically showing a joint used in the joint structure shown in FIG.

The joint 2 shown in FIG. 3 has receiving portions R at both ends. The joint 2 has two receiving portions R. The receiving portion R is a portion into which the resin tube 1 is inserted.

The joint 2 includes a joint body 21 and a second modified layer 22. The second modified layer 22 is arranged on the inner surface 21a of the joint body 21. The second modified layer 22 is arranged on the inner surface 21a of the joint body 21 in the receiving portion R. The second modified layer 22 is the innermost layer of the joint 2 in the receiving portion R. The second modified layer 22 contains a side chain crystalline block copolymer.

FIG. 1 is a cross-sectional view schematically showing a joint structure of a resin pipe and a joint according to the first embodiment of the present invention. The resin pipe shown in FIG. 1 is the resin pipe shown in FIG. 2, and the joint shown in FIG. 1 is the joint shown in FIG.

In FIG. 1, the resin pipe 1 is inserted into the receiving portion R of the joint 2. In the joint structure 4, the joint portion between the resin pipe 1 and the joint 2 has a structure in which the first modified layer 12, the adhesive layer 3, and the second modified layer 22 are arranged in this order. Have. In the joint structure 4, the joint portion between the resin pipe 1 and the joint 2 is radially outward from the center of the joint structure 4, the first modified layer 12, the adhesive layer 3, and the second modification. The layer 22 has a structure in which the layers 22 are arranged in this order. The adhesive layer 3 is a layer formed by an adhesive. The adhesive layer 3 is arranged between the first modified layer 12 and the second modified layer 22. In the joint portion between the resin pipe 1 and the joint 2, more specifically, the resin pipe main body 11, the first modified layer 12, the adhesive layer 3, the second modified layer 22, and the joint. The main body 21 and the main body 21 are arranged in this order.

FIG. 5 is a cross-sectional view schematically showing an example of the resin tube used in the present invention. FIG. 5 is a cross-sectional view schematically showing the resin pipe used in the joint structure shown in FIG.

The resin tube 1A shown in FIG. 5 includes a resin tube main body 11A and a first modified layer 12A. The first modified layer 12A is arranged on the inner surface 11Aa of the resin tube main body 11. The first modified layer 12A is arranged on a part of the inner surface 11Aa of the resin tube main body 11A. The first modified layer 12A reaches one end of the resin tube main body 11A. The first modified layer 12A is the innermost layer of the resin tube 1A at one end of the resin tube 1A. The first modified layer 12A contains a side chain crystalline block copolymer.

FIG. 6 is a cross-sectional view schematically showing an example of a joint used in the present invention. FIG. 6 is a cross-sectional view schematically showing a joint used in the joint structure shown in FIG.

The joint 2A shown in FIG. 6 has outlets RA at both ends. The joint 2A has two spigot RAs.

The joint 2A includes a joint main body 21A and a second modified layer 22A. The second modified layer 22A is arranged on the outer surface 21Aa of the joint body 21A. The second modified layer 22A is arranged on the outer surface 21Aa of the joint body 21A in the spigot portion RA. The second modified layer 22A is the outermost layer of the joint 2A in the spigot portion RA. The second modified layer 22A contains a side chain crystalline block copolymer.

FIG. 4 is a cross-sectional view schematically showing a joint structure of a resin pipe and a joint according to a second embodiment of the present invention. The resin pipe shown in FIG. 4 is the resin pipe shown in FIG. 5, and the joint shown in FIG. 4 is the joint shown in FIG.

In FIG. 4, the resin pipe 1A is inserted into the spigot portion RA of the joint 2A. In the joint structure 4A, the joint portion between the resin pipe 1A and the joint 2A has a structure in which the second modified layer 22A, the adhesive layer 3A, and the first modified layer 12A are arranged in this order. Have. In the joint structure 4A, the joint portion between the resin pipe 1A and the joint 2A is radially outward from the center of the joint structure 4A to the second modified layer 22A, the adhesive layer 3A, and the first modification. The layer 12A has a structure in which the layers 12A are arranged in this order. The adhesive layer 3A is a layer formed by an adhesive. The adhesive layer 3A is arranged between the first modified layer 12A and the second modified layer 22A. In the joint portion between the resin pipe 1A and the joint 2A, more specifically, the joint body 21A, the second modified layer 22A, the adhesive layer 3A, the first modified layer 12A, and the resin pipe. The main body 11A and the main body 11A are arranged in this order.

Hereinafter, details of the resin pipe and the joint, details of the components contained in the adhesive layer, and the like will be described.

(First modified layer and second modified layer)
The first modified layer is a layer arranged on the outer surface or the inner surface of the resin pipe body in the resin pipe.

When the first modified layer is arranged on the outer surface of the resin pipe main body, the first modified layer may be arranged on the entire outer surface of the resin pipe main body, and the resin pipe may be arranged on the entire outer surface. It may be arranged on a part of the outer surface of the main body. When the first modified layer is arranged on the outer surface of the resin pipe main body, the first modified layer is formed on the resin pipe main body at least in a portion inserted into the receiving portion of the joint. It is preferably placed on the outer surface.

When the first modified layer is arranged on the inner surface of the resin pipe main body, the first modified layer may be arranged on the entire inner surface of the resin pipe main body, and the resin pipe may be arranged on the entire inner surface of the resin pipe main body. It may be arranged on a part of the inner surface of the main body. When the first modified layer is arranged on the inner surface of the resin pipe main body, the first modified layer is inside the resin pipe main body at least in a portion to be inserted into the spigot portion of the joint. It is preferably placed on the surface.

The resin pipe may be provided with a modified layer on both the outer surface and the inner surface of the resin pipe body.

The second modified layer is a layer arranged on the inner surface or the outer surface of the joint body in the joint.

When the second modified layer is arranged on the inner surface of the joint body, the second modified layer may be arranged on the entire inner surface of the joint body, and the second modified layer may be arranged on the entire inner surface of the joint body. It may be arranged on a part of the inner surface. When the second modified layer is arranged on the inner surface of the joint body, the second modified layer is preferably arranged on the inner surface of the joint body at the receiving portion. .. In this case, the second modified layer may be arranged on the entire inner surface of the joint body at the receiving portion, or may be arranged on a part of the inner surface of the joint body.

When the second modified layer is arranged on the outer surface of the joint body, the second modified layer may be arranged on the entire outer surface of the joint body, and the second modified layer may be arranged on the entire outer surface of the joint body. It may be arranged on a part of the outer surface. When the second modified layer is arranged on the outer surface of the joint body, it is preferable that the second modified layer is arranged on the outer surface of the joint body at the spigot portion. .. In this case, the second modified layer may be arranged on the entire outer surface of the joint body at the spigot portion, or may be arranged on a part of the outer surface of the joint body.

The joint may be provided with a modified layer on both the outer surface and the inner surface of the joint body.

The first modified layer and the second modified layer each contain a side chain crystalline block copolymer (SCCBC: Side-Chain Crystallinity Block Copolymer). The side chain crystalline block copolymer contained in the first modified layer and the side chain crystalline block copolymer contained in the second modified layer may be the same. It may be different.

Hereinafter, the side chain crystalline block copolymer will be described in detail.

The side chain crystalline block copolymer is a block copolymer of a polymer exhibiting side chain crystallinity and a polymer exhibiting functionality. Therefore, the side chain crystalline block copolymer has a side chain crystalline site (Side-Chain Crystalline Unit) and a functional site (Functional Unit). The side chain crystalline portion is a portion capable of forming a co-crystal with the resin in the resin tube and the resin in the joint. The functional site is a site that exerts a modifying effect.

The side chain crystalline block copolymer is a copolymer of a first monomer capable of forming the side chain crystalline site and a second monomer capable of forming the functional site.

The side chain crystalline block copolymer may be a diblock copolymer or a triblock copolymer. The side chain crystalline block copolymer is a copolymer of the first monomer, the second monomer, and a third monomer different from both the first monomer and the second monomer. It may be.

As used herein, "(meth) acrylate" means one or both of "acrylate" and "methacrylate". Further, in the present specification, "(meth) acrylamide" means one or both of "acrylamide" and "methacrylamide".

<First monomer>
The first monomer is a monomer capable of forming the side chain crystalline site. The side chain crystalline block copolymer has a structure derived from the first monomer. As the first monomer, only one kind may be used, or two or more kinds may be used in combination.

Examples of the first monomer include (meth) acrylate, (meth) acrylamide, vinyl ether, vinyl ester, siloxane, α-olefin, and substituted styrene.

The first monomer preferably has an alkyl group, and more preferably has an alkyl group in the side chain. The alkyl group is preferably a linear alkyl group. In this case, the resin in the resin tube, the resin in the joint, and the side chain crystalline block copolymer can satisfactorily form a co-crystal structure.

The number of carbon atoms of the alkyl group is preferably 8 or more, more preferably 10 or more, still more preferably 12 or more, particularly preferably 14 or more, preferably 50 or less, more preferably 40 or less, still more preferably 30 or less. When the number of carbon atoms of the alkyl group is at least the above lower limit, the resin in the resin tube and the resin in the joint and the side chain crystalline block copolymer can satisfactorily form a co-crystal structure. When the number of carbon atoms of the alkyl group is not more than the above upper limit, the three-dimensional structure of the side chain crystalline block copolymer can be improved.

Specific examples of the alkyl group include a decyl group, a dodecyl group, a tridecylic group, a tetradecyl group, a hexadecyl group, a stearyl group, a docosyl group, and a behenyl group.

The first monomer is a monomer selected from the group consisting of (meth) acrylate, (meth) acrylamide, vinyl ether, vinyl ester, siloxane, α-olefin, and substituted styrene, and contains an alkyl group having 8 or more carbon atoms. It is preferably a monomer having. The first monomer is more preferably a (meth) acrylate having an alkyl group having 8 or more carbon atoms. In this case, the resin in the resin tube, the resin in the joint, and the side chain crystalline block copolymer can satisfactorily form a co-crystal structure.

<Second monomer>
The second monomer is a monomer capable of forming the functional site. The side chain crystalline block copolymer has a structure derived from the second monomer. As the second monomer, only one kind may be used, or two or more kinds may be used in combination.

Examples of the second monomer include (meth) acrylate, (meth) acrylamide, vinyl ether, vinyl ester, siloxane, α-olefin, and substituted styrene.

The second monomer has a functional group for exerting a modifying effect. Since the side chain crystalline block copolymer has the functional group derived from the second monomer, the modification effect is exhibited in the resin pipe and the joint.

In the second monomer, the functional group may be present in the main chain or the side chain.

From the viewpoint of satisfactorily exerting the modifying effect, the functional group is preferably a polar group. Examples of the functional group as the polar group include an amino group, a carboxy group (-COOH), a hirodoxy group (-OH), a carbonyl group (-CO-), an ether group (-O-), and a sulfo group (-SO). ₃ H), an ester group (-COO-), and amide groups (-CON-), and the like. The type of the functional group is appropriately changed according to the type of the adhesive for forming the adhesive layer.

The functional group is preferably an oxyalkylene group, an amino group, an amide group, or a sulfo group. The second monomer preferably has an oxyalkylene group, an amino group, an amide group, or a sulfo group. The functional group may be bonded to the main chain of the second monomer, for example, via an alkylene group having 1 or more and 5 or less carbon atoms.

Second monomer having an oxyalkylene group:
The second monomer may be a monomer having an oxyalkylene group. The oxyalkylene group is a group represented by the general formula _{(C n H 2n} O). In the above general formula, n is preferably an integer of 1 or more and 10 or less. In the above general formula, for example, when n is 1, the oxyalkylene group is called an oxymethylene group (CH ₂ O), and when n is 2, the oxyalkylene group is a dioxyethylene group (CH ₂ CH ₂ O). Is called. When these oxyalkylene groups are linked more polyoxyalkylene groups (general _{formula, (C n H 2n O)} m) called. Typical linear polyoxyalkylene groups (((CH ₂ ) _n O) _m ) include polyoxyethylene ((CH ₂ CH ₂ O) _m ) and the like.

Examples of the second monomer having an oxyalkylene group include a (meth) acrylate having an oxyalkylene group, a (meth) acrylamide having an oxyalkylene group, a vinyl ether having an oxyalkylene group, a vinyl ester having an oxyalkylene group, and an oxyalkylene. Examples thereof include siloxane having a group, α-olefin having an oxyalkylene group, and substituted styrene having an oxyalkylene group. The oxyalkylene group may be present in the main chain of the second monomer or in the side chain.

Specific examples of the second monomer having an oxyalkylene group include di (ethylene glycol) ethyl ether acrylate (CH ₂ = CH (CO) O (CH _2- CH _2- O-) ₂ C ₂ H _5). ), Polyethylene glycol-monoacrylate (CH ₂ = CH (CO) O (CH _2- CH _2- O-) _n H) (preferably n is 2 to 10), and methoxy-polyethylene glycol-acrylate (CH _2). = CH (CO) O (CH _2- CH _2- O-) _n CH ₃ ) (preferably n is 2 to 9) and the like.

Second monomer having an amino group:
The second monomer may be a monomer having an amino group. The amino group may be a primary amino group, a secondary amino group, a tertiary amino group, or a quaternary amino group.

Examples of the second monomer having an amino group include (meth) acrylate having an amino group, (meth) acrylamide having an amino group, vinyl ether having an amino group, vinyl ester having an amino group, siloxane having an amino group, and amino. Examples thereof include α-olefin having a group and substituted styrene having an amino group. The amino group may be present in the main chain of the second monomer or in the side chain.

From the viewpoint of exerting the modifying effect even more effectively, the second monomer having the amino group is a monomer having a secondary amino group, a tertiary amino group, or a quaternary amino group. Is preferable.

Specific examples of the second monomer having an amino group include 2- (dimethylamino) ethyl methacrylate (2- (Dimethylamino) ethyl methyllate, DMAEMA) and 2- (dimethylamino) ethyl acrylate (2- (Dimethylamino)). ) Ethyl Acrylate, DMAEA), 2- (Diethylamino) Ethyl methacrylate (2- (Diethylamino) ether Mythyllate, DEAEMA), 2- (Diethylamino) ethyl acrylate (2- (Diethylamino) ethyl Alylate, DEAEA) -Butylamino) ethyl methacrylate (2- (tert-Butylamino) ethyl acrylate, TBAEMA) and the like can be mentioned.

Second monomer having an amide group:
The second monomer may be a monomer having an amide group.

Examples of the second monomer having an amide group include (meth) acrylate having an amide group, (meth) acrylamide having an amide group, vinyl ether having an amide group, vinyl ester having an amide group, siloxane having an amide group, and amide. Examples thereof include α-olefin having a group and substituted styrene having an amide group. The amide group may be present in the main chain of the second monomer or in the side chain.

Specific examples of the second monomer having an amide group include N, N-dimethylacrylamide (N, N-Dimethylacrylamide, DMAA), N, N-dimethylaminopropylacrylamide (N, N-Dimethylaminopropyl Acrylamide, DMAPAA). ), And N, N-diethylacrylamide (N, N-Diethylamilide, DEAA) and the like.

Second monomer having a sulfo group:
The second monomer may be a monomer having a sulfo group. The sulfo group may be present in the main chain of the second monomer or in the side chain.

Specific examples of the second monomer having a sulfo group include vinyl sulfonic acid, 2- (methacryloyloxy) ethanesulfonic acid, ATBS (Acrylamide Tertiary Butyl Sulfonic Acid), and ATBSNa which is a sodium salt of ATBS. Can be mentioned.

In the side chain crystalline block copolymer, the first monomer and the second monomer are polymerized by known living polymerization methods (living radical polymerization method, living anion polymerization method, and living cationic polymerization method). Can be produced by Examples of the living radical polymerization method include an NMP method, an ATRP method, and a RAFT method.

The side chain crystalline block copolymer can be produced, for example, as follows.

The first monomer, the polymerization initiator and the solvent are mixed to prepare a mixed solution. The obtained mixed solution is heated (for example, 90 ° C. to 120 ° C.), and the first monomer is polymerized under a nitrogen atmosphere while appropriately stirring in the reactor to obtain a polymer of the first monomer. Next, the second monomer is mixed with the solution containing the polymer of the first monomer, and the second monomer is polymerized to obtain a side chain crystalline block copolymer.

In the side chain crystalline block copolymer, the molecular weight of the side chain crystalline site (structure derived from the first monomer) is preferably 500 or more, more preferably 1000 or more, and 2000. The above is more preferable. In this case, the resin in the resin tube, the resin in the joint, and the side chain crystalline block copolymer can satisfactorily form a co-crystal structure.

In the side chain crystalline block copolymer, the molecular weight of the functional site (structure derived from the second monomer) is preferably 500 or more, more preferably 1000 or more, and 2000 or more. It is more preferable to have.

The molecular weight is preferably the weight average molecular weight (Mw). The weight average molecular weight (Mw) indicates the polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography (GPC).

The side chain crystalline site (structure derived from the first monomer) is difficult to dissolve in a solvent, and it may be difficult to measure the weight average molecular weight by GPC. In this case, the molecular weight may be the molecular weight measured by elemental analysis, IR, NMR or the like.

Examples of the side chain crystalline block copolymer include a copolymer having a structure represented by the following formula (1) and the like.

In the above equation (1), R ₁ and R ₂ each represent a hydrogen atom or an arbitrary group, m represents an integer of 2 or more, n represents an integer of 2 or more, and x represents an integer of 1 or more. .. In the above formula (1), R ₁ and R ₂ may be the same or different.

The side chain crystalline block copolymer having the structure represented by the above formula (1) uses, for example, behenyl acrylate and stearyl as the first monomer, and methacrylic as the second monomer. And can be prepared using amine or the like.

In the above formula (1), _{a preferable combination of R 1} and R ₂ is a combination of a hydrogen atom and a hydrocarbon group, or a combination of a hydrocarbon group and a hydrocarbon group.

In the above formula (1), m is preferably 5 or more, more preferably 10 or more, preferably 1000 or less, more preferably 800 or less, and even more preferably 500 or less. In the above formula (1), n is preferably 5 or more, more preferably 10 or more, preferably 1000 or less, more preferably 800 or less, and even more preferably 500 or less. In the above formula (1), x is preferably 8 or more.

A resin pipe (modified resin pipe) having a resin pipe main body and a first modified layer and a joint having a joint main body and a second modified layer (modified joint) are, for example, modified. It can be produced by introducing the side chain crystalline block copolymer into the previous resin pipe and the joint before modification. Specifically, it can be produced as follows.

A solution A in which the side chain crystalline block copolymer is dissolved in a solvent is prepared. Next, the resin pipe before modification and the portion of the joint before modification to be modified are brought into contact with the solution A. As a result, the side chain crystalline block copolymer and the resin are compatible with each other. Next, the resin pipe and the joint are dried to volatilize the solvent. In this way, a resin pipe (modified resin pipe) having a resin pipe main body and a first modified layer, and a joint having a joint main body and a second modified layer (modified joint). ) And can be manufactured.

Depending on the structure of the side chain crystalline block copolymer, it may be difficult to completely dissolve it in the solvent. Therefore, in solution A, the side chain crystalline block copolymer may or may not be completely dissolved. The solution A may be a suspension of the side chain crystalline block copolymer or a dispersion.

Examples of the solvent include aromatic hydrocarbon solvents, halogenated aromatic hydrocarbon solvents, alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, aliphatic hydrocarbon solvents, and halogenated solvents. Examples thereof include aliphatic hydrocarbon solvents, dimethylsulfoxide, and ionic liquids. Only one type of the solvent may be used, or two or more types may be used in combination.

Examples of the aromatic hydrocarbon solvent include toluene, xylene (o-xylene, m-xylene, p-xylene, and mixtures thereof), mesitylene, ethylbenzene, cyclohexylbenzene, and the like.

Examples of the halogenated aromatic hydrocarbon solvent include chlorobenzene, dichlorobenzene, trichlorobenzene, bromobenzene, fluorobenzene and the like.

Examples of the alcohol solvent include ethylene glycol, glycerin, 2-methoxyethanol, 2-ethoxyethanol and the like.

Examples of the ether solvent include tetrahydrofuran, 1,4-dioxane, dimethoxyethane, cyclopentyl methyl ether, diglyme, anisole, methyl anisole, dimethoxybenzene and the like.

Examples of the ketone solvent include methyl isobutyl ketone, cyclohexanone, acetophenone and the like.

Examples of the amide solvent include N, N-dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone and the like.

Examples of the ester solvent include ethyl acetate, butyl acetate, methyl benzoate and the like.

Examples of the aliphatic hydrocarbon solvent include pentane, hexane, octane, decane, cyclohexane, and decalin.

Examples of the halogenated aliphatic hydrocarbon solvent include trichlormethane, tetrachloromethane, dichloroethane, trichlorethylene, tetrachlorethylene, chlorobutane, bromoform and the like.

Examples of the ionic liquid include ammonium salt-based ionic liquids and imidazolium salt-based ionic liquids. Examples of the ammonium salt-based ionic liquid include tetrabutylammonium acetate, dodecyltrimethylammonium chloride, and tetrahexyl ammonium bromide. Examples of the imidazolium salt-based ionic liquid include 1-butyl-3-methyl-imidazolium chloride, 1-butyl-3-methyl-imidazolium methylsulfate, and 1-butyl-3-methyl-imidazolium iodine. Do etc. can be mentioned.

The solvent is preferably toluene, xylene, butyl acetate, octane, or decalin.

The content of the side chain crystalline block copolymer in 100% by weight of the solution A is preferably 0.01% by weight or more, more preferably 0.02% by weight or more, still more preferably 0.05% by weight or more. It is preferably 2.0% by weight or less, more preferably 1.5% by weight or less, still more preferably 1.0% by weight or less. When the content of the side chain crystalline block copolymer is at least the above lower limit, the modified layer can be formed satisfactorily. When the content of the side chain crystalline block copolymer is not more than the above upper limit, aggregation of the side chain crystalline block copolymer in the solution A can be effectively suppressed.

As a method of contacting the portion of the resin pipe before modification and the joint before modification to be modified with the solution A, a method of immersing the portion to be modified in the solution A (dipping) or solution A is used. Examples thereof include a method of contacting while circulating (flowing, etc.), a method of applying solution A (coating), a method of spraying solution A using a sprayer, a sprayer, or the like.

The contact time between the resin pipe before modification and the portion of the joint before modification to be modified and the solution A can be appropriately changed. The contact time is preferably 1 second or longer, more preferably 2 seconds or longer, more preferably 10 seconds or longer, still more preferably 30 seconds or longer, particularly preferably 1 minute or longer, preferably 60 minutes or shorter, more preferably 50 minutes or longer. Below, it is more preferably 40 minutes or less, particularly preferably 30 minutes or less, and most preferably 20 minutes or less. When the contact time is at least the above lower limit, the modified layer can be formed satisfactorily. When the contact time is not more than the above upper limit, deformation of the resin pipe and the joint can be effectively suppressed.

The temperature of the solution A when the resin pipe before modification and the portion of the joint before modification to be modified are brought into contact with the solution A is preferably 40 ° C. or higher, more preferably 45 ° C. or higher, still more preferable. Is 50 ° C. or higher, particularly preferably 60 ° C. or higher, most preferably 65 ° C. or higher, preferably 120 ° C. or lower, more preferably 115 ° C. or lower, still more preferably 110 ° C. or lower, still more preferably 100 ° C. or lower, even further. It is preferably 95 ° C. or lower, particularly preferably 90 ° C. or lower. When the temperature of the solution A is equal to or higher than the above lower limit, the modified layer can be satisfactorily formed. When the temperature of the solution A is not more than the above upper limit, deformation of the resin pipe and the joint can be effectively suppressed.

Further, the resin pipe (modified resin pipe) having the resin pipe main body and the first modified layer and the joint having the joint main body and the second modified layer (modified joint) are as follows. It can also be manufactured as in (1), (2), or (3).

(1) The resin pipe before modification in a high temperature state and the portion of the joint before modification in a high temperature state to be modified are brought into contact with the above solution A at room temperature. The resin pipe before modification in a high temperature state and the joint before modification in a high temperature state may be, for example, a resin pipe (resin pipe body) and a joint (joint body) during or immediately after molding, and may be a heater and an oven. It may be a resin pipe (resin pipe main body) and a joint (joint main body) reheated by the above. As a method of contacting the solution A at room temperature, a method of immersing the portion to be modified in the solution A (dipping), a method of contacting the solution A while circulating it (flowing, etc.), a spray, a sprayer, or the like is used. A method of spraying the solution A and the like can be mentioned. The temperature of the resin pipe before modification and the joint before modification when contacting with the solution A is preferably 40 ° C. or higher, more preferably 60 ° C. or higher, further preferably 90 ° C. or higher, and particularly preferably 120 ° C. or higher. The temperature is most preferably 130 ° C. or higher, preferably 220 ° C. or lower, more preferably 200 ° C. or lower, still more preferably 180 ° C. or lower, and particularly preferably 150 ° C. or lower. When the temperature of the resin pipe before modification and the joint before modification is equal to or higher than the above lower limit, the modification effect is effectively exhibited and the modified layer can be formed satisfactorily. Further, since the resin pipe before modification and the joint before modification are usually formed by molding a resin heated to a temperature higher than the melting point and then cooling, the resin tube before modification and the modified joint are formed. When the temperature of the joint before quality is not more than the above upper limit, the shape, size and appearance of the resin pipe and the joint can be improved.

(2) Using the first material containing the solution A or the powdery (solid) side chain crystalline block copolymer and the second material containing the resin, the resin tube body and the first modification A resin pipe having a layer (modified resin pipe) or a joint having a joint body and a second modified layer (modified joint) is formed. In this case, the first material may contain only the side chain crystalline block copolymer or may not contain the resin, and may contain the side chain crystalline block copolymer and the resin. You may. The resin tube provided with the resin tube main body and the first modified layer is formed on a resin tube main body obtained by co-extruding the first material and the second material or extruding the second material. It can be obtained by post-coating the first modified layer obtained by extruding the first material. A joint provided with a joint body and a second modified layer is obtained by multi-layer injection molding of the first material and the second material, or molding of the first material to obtain an insert part. It can be obtained by injection insert molding.

(3) A material containing a side-chain crystalline block copolymer is independently extrusion-molded or injection-molded, and the resulting molded product is inclined by utilizing the fact that a concentration gradient of the side-chain crystalline block copolymer can be formed. Side chain crystalline block copolymers are distributed in. In this way, a resin pipe (modified resin pipe) having a resin pipe main body and a first modified layer, or a joint having a joint main body and a second modified layer (modified joint). ) Is molded.

The first modified layer usually contains the same resin as the resin contained in the resin tube body. The first modified layer preferably has a co-crystal structure of the resin and the side chain crystalline block copolymer. The first modified layer may contain other components such as fibers and pigments described later.

The second modified layer usually contains the same resin as the resin contained in the joint body. The second modified layer preferably has a co-crystal structure of the resin and the side chain crystalline block copolymer. The second modified layer may contain other components such as fibers and pigments described later.

The first modified layer may be adjacent to the resin tube body at an interface, or side chain crystalline block copolymers may be distributed and present in an inclined manner. The second modified layer may be adjacent to the joint body at the interface, or the side chain crystalline block copolymer may be distributed and present in an inclined manner.

The thickness of the first modified layer is preferably 1 nm or more, more preferably 10 nm or more, preferably 1 μm or less, and more preferably 100 nm or less. When the thickness of the first modified layer is equal to or greater than the above lower limit and equal to or less than the above upper limit, the effect of the present invention can be more effectively applied to the resin tube modified by the modifying method by dipping, flowing and spraying. It can be demonstrated.

The thickness of the first modified layer is preferably 1 μm or more, more preferably 10 μm or more, preferably 5 mm or less, and more preferably 1 mm or less. When the thickness of the first modified layer is not less than the above lower limit and not more than the above upper limit, a resin tube can be satisfactorily produced by coextrusion and post-coating, and the effect of the present invention can be obtained in the resin tube. It can be exhibited even more effectively.

The thickness of the second modified layer is preferably 1 nm or more, more preferably 10 nm or more, preferably 1 μm or less, and more preferably 100 nm or less. When the thickness of the second modified layer is equal to or greater than the above lower limit and equal to or less than the above upper limit, the effect of the present invention is more effectively exhibited in the joint modified by the modifying method by dipping, flowing and spraying. Can be made to.

The thickness of the second modified layer is preferably 1 μm or more, more preferably 100 μm or more, preferably 10 mm or less, and more preferably 5 mm or less. When the thickness of the second modified layer is not less than the above lower limit and not more than the above upper limit, a joint can be satisfactorily manufactured by multi-layer injection molding and injection insert molding, and the effect of the present invention can be obtained in the joint. It can be exerted even more effectively.

(Resin pipe body and joint body)
The resin tube body contains a resin. The joint body preferably contains a resin. Only one type of the above resin may be used, or two or more types may be used in combination.

Examples of the resin include olefin resins, fluororesins, vinyl chloride resins and the like.

From the viewpoint of exerting the effect of the present invention more effectively, the resin tube main body preferably contains an olefin resin or a fluorine resin.

From the viewpoint of exerting the effects of the present invention even more effectively, the joint body preferably contains an olefin resin or a fluorine resin.

Examples of the olefin resin include polyethylene, polypropylene, polybutene, ethylene-vinyl acetate copolymer, ethylene-α-olefin copolymer and the like. The olefin resin may be a crosslinked olefin resin. Only one type of the olefin resin may be used, or two or more types may be used in combination.

The polypropylene may be a homopolymer, a block polymer, or a random polymer.

From the viewpoint of exerting the effects of the present invention even more effectively, the olefin resin is preferably polyethylene, cross-linked polyethylene or polypropylene.

Examples of the fluororesin include a homopolymer having a fluorinated α-olefin monomer as a structural unit, a copolymer containing a fluorinated α-olefin monomer as a structural unit, and the like.

The fluorinated α-olefin monomer is an α-olefin monomer containing a substituent having at least one fluorine atom.

Examples of the fluorinated α-olefin monomer include tetrafluoroethylene (CF ₂ = CF ₂ ), CHF = CF ₂ , vinylidene fluoride (CH ₂ = CF ₂ ), CH ₂ = CHF, and chlorotrifluoroethylene (CClF = CF). ₂ ), CCl ₂ = CF ₂ , CClF = CClF, CHF = CCl ₂ , CH ₂ = CClF, CCl ₂ = CClF, Hexafluoropropylene (CF ₂ = CFCF ₃ ), CF ₃ CF = CHF, CF ₃ CH = CF ₂ , CF ₃ CH = CH ₂ , CF ₃ CF = CHF, CHF ₂ CH = CHF, CF ₃ CH = CH _{2, and the} like.

Examples of the fluororesin include poly (tetrafluoroethylene) homopolymer (PTFE), poly (hexafluoroethylene), poly (tetrafluoroethylene-hexafluoroethylene), poly (tetrafluoroethylene-ethylene-propylene) and the like. Can be mentioned. The poly (tetrafluoroethylene) homopolymer (PTFE) may be fibrogenic or non-fibrous.

The content of the resin in 100% by weight of the resin tube is preferably 70% by weight or more, more preferably 75% by weight or more, preferably 95% by weight or less, and more preferably 90% by weight or less. When the content of the resin is not less than the above lower limit and not more than the above upper limit, the pressure resistance of the resin tube can be further increased.

The content of the resin in 100% by weight of the joint is preferably 70% by weight or more, more preferably 75% by weight or more, preferably 95% by weight or less, and more preferably 90% by weight or less. When the content of the resin is not less than the above lower limit and not more than the above upper limit, the pressure resistance of the joint can be further increased.

The resin tube body and the joint body are fibers, compatibilizers, stabilizers, stabilizing aids, lubricants, processing aids, impact modifiers, heat resistance improvers, antioxidants, UV absorbers, and light stabilizers, respectively. It may contain other components such as agents, fillers, pigments and plasticizers.

The fiber may be an inorganic fiber or an organic fiber.

Examples of the inorganic fiber include glass fiber, carbon fiber, silicon / titanium / carbon composite fiber, boron fiber, metal fiber and the like.

Examples of the organic fiber include aramid fiber, vinylon fiber, polyester fiber, polyamide fiber and the like.

From the viewpoint of further increasing the pressure resistance, the fiber is preferably glass fiber.

The average fiber length of the fibers is preferably 100 μm or more, more preferably 200 μm or more, still more preferably 500 μm or more, preferably 1500 μm or less, more preferably 1000 μm or less, still more preferably 800 μm or less. When the average fiber length of the fibers is at least the above lower limit, the pressure resistance of the resin tube can be further increased. When the average fiber length of the fibers is not more than the upper limit, the fibers can be easily arranged in a specific direction.

The average fiber length is obtained by obtaining the fiber length of one fiber and averaging the fiber lengths of a plurality of fibers. The fiber length is the distance between one end and the other end of the fiber when the fiber is straightened.

The average fiber diameter of the fibers is preferably 5 μm or more, more preferably 7 μm or more, still more preferably 9 μm or more, preferably 17 μm or less, more preferably 13 μm or less, still more preferably 11 μm or less. When the average fiber diameter of the fibers is at least the above lower limit, the pressure resistance of the resin tube can be further increased. When the average fiber diameter of the fibers is not more than the upper limit, the fibers can be easily arranged in a specific direction.

The average fiber diameter is obtained by determining the fiber diameter of one fiber and averaging the fiber diameters of a plurality of fibers.

The content of the fiber in 100% by weight of the resin tube is preferably 5% by weight or more, more preferably 10% by weight or more, preferably 30% by weight or less, and more preferably 25% by weight or less. When the fiber content is at least the above lower limit and at least the above upper limit, the pressure resistance of the resin tube can be further increased.

The compatibilizer is not particularly limited, and examples thereof include maleic acid-modified polyolefin, silane-modified polyolefin, and chlorinated polyolefin. These compatibilizers are not included in the olefin resin. Only one kind of the compatibilizer may be used, or two or more kinds thereof may be used in combination.

The stabilizer is not particularly limited, and examples thereof include a heat stabilizer and a heat stabilization aid. The heat stabilizer is not particularly limited, and examples thereof include an organotin stabilizer, a lead stabilizer, a calcium-zinc stabilizer, a barium-zinc stabilizer, and a barium-cadmium stabilizer. Examples of the organic tin stabilizer include dibutyl tin mercapto, dioctyl tin mercapto, dimethyl tin mercapto, dibutyl tin mercapto, dibutyl tin malate, dibutyl tin malate polymer, dioctyl tin malate, dioctyl tin malate polymer, dibutyl tin laurate, and the like. Examples thereof include dibutyltin laurate polymer. Only one kind of the above stabilizer may be used, or two or more kinds may be used in combination.

The heat stabilizing aid is not particularly limited, and examples thereof include epoxidized soybean oil, phosphoric acid ester, polyol, hydrotalcite, and zeolite. As the heat stabilizing aid, only one kind may be used, or two or more kinds may be used in combination.

The lubricant is not particularly limited, and examples thereof 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 examples thereof include butyl stearate, lauryl alcohol, stearyl alcohol, epoxy soybean oil, glycerin monostearate, stearic acid, and bisamide. 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 examples thereof include paraffin wax, polyolefin wax, ester wax, and montanic acid wax. Only one kind of the above-mentioned lubricant may be used, or two or more kinds may be used in combination.

The processing aid is not particularly limited, and examples thereof include an acrylic processing aid. Examples of the acrylic processing aid include alkyl acrylate-alkyl methacrylate copolymers having a weight average molecular weight of 100,000 to 2 million, and specifically, n-butyl acrylate-methyl methacrylate copolymer and n-butyl acrylate-methyl methacrylate copolymer. Examples thereof include 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymer. As the processing aid, only one kind may be used, or two or more kinds may be used in combination.

The impact modifier is not particularly limited, and examples thereof include methyl methacrylate-butadiene-styrene copolymer (MBS), chlorinated polyethylene, and acrylic rubber. Only one type of the impact modifier may be used, or two or more types may be used in combination.

The heat resistance improving agent is not particularly limited, and examples thereof include α-methylstyrene-based resins and N-phenylmaleimide-based resins. Only one kind of the heat resistance improving agent may be used, or two or more kinds thereof may be used in combination.

The antioxidant is not particularly limited, and examples thereof include phenolic antioxidants. Only one kind of the above-mentioned antioxidant may be used, or two or more kinds may be used in combination.

The ultraviolet absorber is not particularly limited, and examples thereof include a salicylate ester-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber. Only one kind of the above-mentioned ultraviolet absorber may be used, or two or more kinds may be used in combination.

The light stabilizer is not particularly limited, and examples thereof include hindered amine-based light stabilizers. Only one kind of the above-mentioned light stabilizer may be used, or two or more kinds thereof may be used in combination.

The filler is not particularly limited, and examples thereof include calcium carbonate, clay, and talc. Only one kind of the filler may be used, or two or more kinds thereof may be used in combination.

The pigment is not particularly limited, and examples thereof include organic pigments and inorganic pigments. Examples of the organic pigments include azo-based organic pigments, phthalocyanine-based organic pigments, slene-based organic pigments, and dye lake-based organic pigments. Examples of the inorganic pigments include oxide-based inorganic pigments, molybdenum chromate-based inorganic pigments, sulfide / selenium-based inorganic pigments, and ferrosinide-based inorganic pigments. Only one kind of the above pigment may be used, or two or more kinds may be used in combination.

The plasticizer may be added for the purpose of improving processability at the time of molding. Since the heat resistance of the molded product may decrease due to the addition of the plasticizer, it is preferable that the amount of the plasticizer added is small. The plasticizer is not particularly limited, and examples thereof include dibutyl phthalate, di-2-ethylhexyl phthalate, and di-2-ethylhexyl adipate. Only one type of the above-mentioned plasticizer may be used, or two or more types may be used in combination.

The resin tube main body may have a structure of one layer or may have a structure of two or more layers.

The shape of the resin tube is not particularly limited. As the shape of the resin tube, a conventionally known shape can be used. The resin pipe may be a straight pipe or a pipe having a bending angle.

The shape of the joint is not particularly limited. As the shape of the joint, a conventionally known shape can be used. The joint may be, for example, an elbow joint, a cheese joint, a cheese joint having a different diameter, or a socket joint having a different diameter.

Further, the receiving portion of the joint may have a tapered portion arranged on the outer side in the axial direction of the receiving portion and a parallel portion arranged on the inner side in the axial direction of the receiving portion. In this case, the tapered portion and the parallel portion are preferably connected to each other, and the tapered portion is preferably inclined so that the inner diameter becomes smaller toward the parallel portion. The tapered portion refers to a portion having an inclination angle of 1 ° or more in the axial direction of the receiving portion. The parallel portion refers to a portion having an inclination angle of less than 1 ° in the axial direction of the receiving portion.

In a joint having the tapered portion and the parallel portion, it is preferable that the modified layer is arranged on the inner surface of the joint body at least in the parallel portion.

(Adhesive layer)
The adhesive layer is formed by an adhesive. The adhesive is not particularly limited. Examples of the adhesive include vinyl polymerization adhesives such as cyanoacrylate, polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyacrylic acid ester, and ethylene copolymer; cellulose adhesives such as cellulose ester and cellulose ether. Polycondensation / polyaddition adhesives such as saturated polyester, polyamide, and cotton-like polyimide; epoxy resin, polyurethane resin, silylated urethane resin, unsaturated polyester, reactive acrylic resin, modified silicone resin, melamine resin, Thermo-curable resin adhesives such as urea resin and phenol resin; rubber adhesives such as chloroprene rubber, nitrile rubber, styrene butadiene rubber, butyl rubber, styrene block copolymer, and silicone rubber; vinyl phenolic, nitrile Examples thereof include a mixed adhesive containing phenolic, epoxy nylon and the like as main components.

Commercially available products of the above adhesives include "Aron Alpha (registered trademark)" manufactured by Toagosei Co., Ltd., "Esdyne" manufactured by Sekisui Chemical Industry Co., Ltd., "Eslon Adhesive", "Bond SU" manufactured by Konishi Co., Ltd., and "PPX" manufactured by Semedyne Co., Ltd. And so on. The adhesive may be selected according to the characteristics of the modified layer.

The thickness of the adhesive layer is preferably 0.1 μm or more, more preferably 10 μm or more, preferably 3 mm or less, and more preferably 1 mm or less. When the thickness of the adhesive layer is equal to or greater than the lower limit and equal to or lower than the upper limit, the adhesive force between the first modified layer and the second modified layer and the adhesive layer can be enhanced, and the effect of the present invention can be enhanced. It can be exhibited even more effectively. When the thickness of the adhesive layer is less than 0.1 μm, the thickness of the adhesive layer is more likely to be uneven than when it is 0.1 μm or more, and the first modified layer and the second modified layer are more likely to be uneven. The adhesive strength between the modified layer and the adhesive layer may decrease. Further, when the thickness of the adhesive layer exceeds 1 mm, the shear strength of the adhesive layer itself may decrease as compared with the case where the thickness is 1 mm or less.

(Joint structure of resin pipe and joint)
The joint structure of the resin pipe and the joint according to the present invention can be manufactured as described in (1) or (2) below.

(1) After applying the adhesive to at least one of the outer surface of the first modified layer of the resin pipe and the inner surface of the second modified layer of the joint, the receiving portion of the joint is covered. Insert the above resin tube.

(2) After applying the adhesive to at least one of the inner surface of the first modified layer of the resin pipe and the outer surface of the second modified layer of the joint, the joint has an outlet. Insert the above resin tube.

The joint structure between the resin pipe and the joint according to the present invention can be confirmed by, for example, an electron microscope, FT-IR, or the like.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited to the following examples.

The following sample 1 having the shape shown in FIG. 7 (a) was prepared.

Sample 1 (polypropylene, length 85 mm, width 20 mm at one end, width 10 mm at the other end, thickness 3 mm)
The following adhesives were prepared.

"Aron Alpha (registered trademark)" manufactured by Toagosei Co., Ltd., cyanoacrylate adhesive

(Example 1)
Preparation of Side Chain Crystalline Block Copolymer:
Using behenyl acrylate (BHA) as the first monomer and 2- (tert-butylamino) ethyl methacrylate (2 (tert-Butyl-amino) ether polymer: TBAEMA) as the second monomer, the following formula is used. A side chain crystalline block copolymer having the structure represented by (2) was prepared.

Preparation of solution A:
The obtained side chain crystalline block copolymer and xylene were mixed to prepare a solution A having a side chain crystalline block copolymer content of 0.1% by weight.

Preparation of dumbbell-shaped test pieces:
Solution A was heated to 85 ° C. In the two samples 1, a region of 30 mm or more from the other end was immersed in the warmed solution A for 5 minutes. After the immersion, the two samples 1 were taken out and air-dried. In this way, two samples 1 on which the modified layer was formed were obtained.

Next, an adhesive was applied to the surface of the modified layer of one sample 1, and the modified layer of the other sample 1 was placed on the surface of the applied adhesive. In this way, a dumbbell-shaped test piece (a test piece having the shape shown in FIG. 7B) in which the two samples 1 were adhered with an adhesive was prepared. The adhesive length L was 20 mm.

(Comparative Example 1)
A dumbbell-shaped test piece was prepared in the same manner as in Example 1 except that the modified layer was not formed and the two samples 1 were adhered with an adhesive.

(evaluation)
(1) Repeated fatigue characteristics at room temperature (23 ° C) and high temperature (90 ° C) Repeated fatigue characteristics of the obtained dumbbell-shaped test piece using a servo pulsar (“EHF-ED1KNX4-4LA” manufactured by Shimadzu Corporation). Was evaluated. The test conditions were 23 ° C. and 90 ° C., a frequency of 1.0 MHz, a sine wave waveform, and the load conditions shown in Tables 1 and 2. The number of times (the number of breaks) until the dumbbell-shaped test piece broke was determined. In addition, the result of ">" in Table 1 means that the dumbbell-shaped test piece did not break even when the load was applied the number of times.

The results are shown in Tables 1 and 2 below. Further, FIG. 8A shows the result of the repeated fatigue characteristic of Example 1 at room temperature (23 ° C.), and FIG. 8B shows the result of the repeated fatigue characteristic of Example 1 at a high temperature (90 ° C.). show. Further, FIG. 9A shows the result of the repeated fatigue characteristic of Comparative Example 1 at room temperature (23 ° C.), and FIG. 9B shows the result of the repeated fatigue characteristic of Comparative Example 1 at a high temperature (90 ° C.). show.

In Examples and Comparative Examples, dumbbell-shaped test pieces were evaluated. Even when the resin pipe and the joint are used, the same results as in the examples and comparative examples can be obtained.

1,1A ... Resin pipe 2,2A ... Joint 3,3A ... Adhesive layer 4,4A ... Joint structure 11,11A ... Resin pipe body 11a ... Outer surface 11Aa ... Inner surface 12,12A ... First modified layer 21 , 21A ... Joint body 21a ... Inner surface 21Aa ... Outer surface 22,22A ... Second modified layer R ... Receptacle RA ... Outlet

Claims (3)

It is a joint structure of a resin pipe and a joint,
The resin tube includes a resin tube main body and a first modified layer arranged on the outer surface of the resin tube main body.
The joint comprises a joint body and a second modified layer disposed on the inner surface of the joint body.
The first modified layer and the second modified layer each contain a side chain crystalline block copolymer.
A resin pipe and a joint having a structure in which the first modified layer, the adhesive layer, and the second modified layer are arranged in this order at the joint portion between the resin pipe and the joint. Joint structure. It is a joint structure of a resin pipe and a joint,
The resin tube includes a resin tube main body and a first modified layer arranged on the inner surface of the resin tube main body.
The joint comprises a joint body and a second modified layer disposed on the outer surface of the joint body.
The first modified layer and the second modified layer each contain a side chain crystalline block copolymer.
A resin pipe and a joint having a structure in which the second modified layer, the adhesive layer, and the first modified layer are arranged in this order at a joint portion between the resin pipe and the joint. Joint structure. The resin tube body contains an olefin resin or a fluorine resin, and contains
The joint structure between a resin pipe and a joint according to claim 1 or 2, wherein the joint body contains an olefin resin or a fluorine-based resin.

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