JP2008523199A - Blocking pipe - Google Patents

Abstract

  The present invention relates to a barrier pipe, and the barrier pipe manufactured by molding a dry-mixed composition of a polyolefin resin, a barrier nanocomposite, a compatibilizer, and a physical property enhancer has excellent barrier properties. It is particularly useful for automobile filler pipes and air conditioner pipes.

Description

  The present invention relates to a barrier pipe manufactured from a composition formed by drying and mixing a polyolefin resin, a nanocomposite of a layered clay compound and a barrier resin, a compatibilizer and a physical property enhancer.

  Pipes for circulating hot water, automobile filler pipes, air conditioner pipes, gas pipes, etc. need gas barrier properties, oxygen barrier properties, moisture barrier properties, etc. so that air, gas, etc. contained therein do not leak outside.

  Conventionally, metal hot water circulation pipes are mainly used for floor heating by the hot water circulation method. Pipes for hot water circulation are often buried under the concrete and installed under the floor when constructed. Once installed, repairs afterwards are quite difficult and generally have a long-term durability of about 50 years. Is required. Under such strict conditions, it is more desirable to use a plastic pipe that is less expensive than a metal pipe and that does not corrode the pipe material itself. Polyethylene, polypropylene, polybutene, etc. are used as such plastic pipe materials. However, if such plastic pipes are used in a floor heating system based on a hot water circulation system, a problem arises in that metal parts connected to pipes such as heat exchangers and pumps are corroded by oxygen. It is considered that the cause of such corrosion is that oxygen present in the atmosphere permeates and dissolves in warm water circulating in the pipe through the plastic wall. As a result, multi-layer polyethylene pipes (PE / aluminum layer / PE) with aluminum as the intermediate layer are used. However, since the aluminum layer is cracked due to temperature changes, corrosion due to oxygen cannot be prevented. . As such a solution, various multilayer pipes made of a plastic resin and polyethylene having excellent oxygen gas barrier properties have been evaluated. Among these, it has been confirmed that a multilayer pipe using an ethylene-vinyl alcohol copolymer (hereinafter also referred to as EVOH) has the best oxygen barrier properties and mechanical strength. Today, EVOH multilayer plastic pipes are It has begun to be applied as a hot water circulation pipe. However, although EVOH has excellent oxygen barrier properties and mechanical strength, there is a disadvantage that crack resistance is not sufficient due to the problem of EVOH's own rigidity.

  On the other hand, in the case of an automobile filler pipe, for example, a co-extrusion blow-molded plastic pipe is advantageously used to supply gasoline. Conventionally, polyethylene has been generally used as a plastic material for this purpose because of its low cost and excellent molding processability and mechanical strength. However, this has the disadvantage that the barrier property is not sufficient and the vapor or liquid of gasoline in the pipe easily evaporates into the atmosphere through the polyethylene wall of the pipe.

  In order to overcome such drawbacks, a pipe having a multilayer structure of an ethylene vinyl alcohol copolymer with good barrier properties and a polyethylene resin was used, but this also means that the barrier properties are always satisfactory. Absent. Aiming at gasoline saving and global environmental protection is a recent trend in the art, and therefore there is a need to further reduce gasoline permeation through fuel pipes.

  Meanwhile, a nano-sized layered clay compound is mixed with the polymer composition to form a nanocomposite in the form of fully exfoliated, partially exfoliated, intercalated, and partially intercalated. Then, since the barrier property is improved by such a morphology, the barrier property article using this has been attracting attention.

  Therefore, the technical problem to be solved by the present invention is to provide a pipe having excellent barrier property and crack resistance by using the barrier resin nanocomposite.

  In order to achieve the technical problem, in the present invention, 1 selected from (a) 40 to 98 parts by weight of a polyolefin resin and (b) ethylene-vinyl alcohol copolymer, polyamide, ionomer and polyvinyl alcohol. 0.5 to 60 parts by weight of a blocking nanocomposite of at least one type of blocking resin and a layered clay compound, (c) 1 to 30 parts by weight of a compatibilizer, (d) low density polyethylene (hereinafter also referred to as LDPE) 1) to 10 parts by weight of one or more physical property reinforcing agents selected from linear low density polyethylene (hereinafter also referred to as LLDPE), very low density polyethylene (hereinafter also referred to as VLDPE) and rubber. An insulating pipe manufactured by molding the prepared composition is provided.

  According to one embodiment of the present invention, the polyolefin resin is selected from the group consisting of high density polyethylene (hereinafter also referred to as HDPE), low density polyethylene, linear low density polyethylene and ethylene-propylene copolymer, metallocene polyethylene, and polypropylene. There may be one or more selected. The polypropylene is one or more selected from the group consisting of a propylene homopolymer or copolymer, a metallocene polypropylene, and a composite resin obtained by adding talc, flame retardant, etc. to a propylene homopolymer or copolymer to enhance the physical properties of general polypropylene. It can be.

  According to another embodiment of the present invention, the layered clay compound is montmorillonite, bentonite, kaolinite, mica, hectorite, hectorite fluoride, saponite, bidelite, nontronite, stevensite, vermiculite, halosite, It may be one or more selected from the group consisting of Volconsky stone, saccoite, magadite and Kenyalite.

  According to still another embodiment of the present invention, the polyamide is 1) nylon 4.6, 2) nylon 6, 3) nylon 6.6, 4) nylon 6.10, 5) nylon 7, 6) nylon 8 7) Nylon 9, 8) Nylon 11, 9) Nylon 12, 10) Nylon 46, 11) MXD6, 12) Amorphous polyamide, 13) Copolymer having two or more components of 1) to 12) A polymerized polyamide or a mixture of two or more of the polyamides of 14) 1) to 12) can be selected and used.

  According to still another embodiment of the present invention, the ionomer may have a melt index of 0.1 to 10 g / 10 min (190 ° C., 2,160 g).

  According to still another embodiment of the present invention, the compatibilizing agent is ethylene-ethylene anhydride-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-alkyl acrylate-acrylic acid copolymer, maleic anhydride. Modified (graft) high density polyethylene, maleic anhydride modified (graft) linear low density polyethylene, ethylene-alkyl methacrylate-methacrylic acid copolymer, ethylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer and maleic anhydride It may be one or more selected from the group consisting of modified (grafted) ethylene-vinyl acetate copolymers.

  According to yet another embodiment of the present invention, the pipe may be in the form of a single layer or multiple layers.

  According to still another embodiment of the present invention, the barrier pipe may be an automobile filler pipe, an air conditioner pipe, a water pipe, a sewer pipe, a hot water circulation pipe, or a gas pipe.

  Hereinafter, the present invention will be described in more detail.

  In the present invention, (a) 40 to 98 parts by weight of a polyolefin resin, and (b) one or more barrier resins selected from the group consisting of ethylene-vinyl alcohol copolymer, polyamide, ionomer and polyvinyl alcohol, and layered clay 0.5 to 60 parts by weight of a blocking nanocomposite with the compound, (c) 1 to 30 parts by weight of a compatibilizer, and (d) one or more selected from LDPE, VLDPE, LLDPE, and rubber A barrier pipe is manufactured by molding a composition in which 1 to 10 parts by weight of the physical property reinforcing agent is dry mixed.

  The polyolefin resin includes at least one selected from the group consisting of high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene-propylene copolymer, metallocene polyethylene and polypropylene. Can be used. The polypropylene is one or more selected from the group consisting of a composite resin in which propylene homopolymers or copolymers, metallocene polypropylene, and propylene homopolymers or copolymers are added with talc, flame retardant, etc. to enhance the physical properties of general polypropylene. Can be used.

  The polyolefin resin is preferably included in an amount of 40 to 98 parts by weight, and more preferably in an amount of 65 to 96 parts by weight. If the olefin resin is less than 40 parts by weight, molding is not easy, and if it exceeds 98 parts by weight, the effect of improving the blocking property is lowered, which is not desirable.

  The barrier nanocomposite of the present invention is a layered clay compound (cray) selected from ethylene-vinyl alcohol copolymer (EVOH), polyamide, ionomer and polyvinyl alcohol (PVA). Can be mixed with

  In the blocking nanocomposite, the weight ratio of the blocking resin to the layered clay compound is 58.0: 42.0 to 99.9: 0.1, preferably 85.0: 15.0. To 99.0: 1.0. If the weight ratio of the blocking resin is less than 58.0, the agglomeration phenomenon of the layered clay compound occurs and the dispersion is not properly performed. If the weight ratio of the blocking resin exceeds 99.9, the blocking performance is increased. The ascending effect is small and undesirable.

  The layered clay compound is preferably an organized layered clay compound in which an organic agent is interposed between layers of the layered clay compound. The organic agent content in the layered clay compound is preferably 1 to 45% by weight. If the content of the organic agent is less than 1% by weight, the compatibility between the layered clay compound and the blocking resin is lowered, and if it exceeds 45% by weight, the insertion of the blocking resin chain between the layers is not easy, which is not desirable.

  The layered clay compound is montmorillonite, bentonite, kaolinite, mica, hectorite, fluorinated hectorite, saponite, bidelite, nontronite, stevensite, vermiculite, halosite, vorconsky stone, sacconite, magadite, and Desirably, at least one selected from the group consisting of Kenyalite is selected, and the organic substance is selected from the group consisting of primary to quaternary ammonium, phosphonium, maleate, succinate, acrylate, hydrogen at benzyl, oxazoline and dimethyl distearyl ammonium It is desirable that the organic material contains a functional group.

  The ethylene content of the ethylene-vinyl alcohol copolymer used in the present invention is preferably 10 to 50 mol%. When the ethylene content is less than 10 mol%, workability is lowered and melt molding is difficult, and when it exceeds 50 mol%, oxygen barrier properties and liquid barrier properties are not sufficient. There is a problem.

  The polyamide used in the present invention is 1) nylon 4.6, 2) nylon 6, 3) nylon 6.6, 4) nylon 6.10, 5) nylon 7, 6) nylon 8, 7) nylon 9, 8 Nylon 11, 9) Nylon 12, 10) Nylon 46, 11) MXD6, 12) Amorphous polyamide, 13) Copolyamide having two or more components of 1) to 12), or 14) 1 A mixture of two or more of the polyamides of) to 12) can be selected and used.

  The amorphous polyamide means a polyamide having no endothermic crystalline melting point peak, that is, insufficient crystallinity, when measured with a differential scanning calorimeter (DSC) (ASTMD-3417, 10 ° C./min).

  In general, polyamides can be made from diamines and dicarboxylic acids. Examples of diamines include hexamethylenediamine, 2-methylpentamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, bis (4-aminocyclohexyl) methane, 2, 2-bis (4-aminocyclohexyl) isopropylidene, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, meta-xylenediamine, 1,5-diaminopentane, 1,4-diaminobutane, 1,3-diamino Examples include propane, 2-ethyldiaminobutane, 1,4-diaminomethylcyclohexane, methane-xylenediamine, alkyl-substituted or unsubstituted m-phenylenediamine, and p-phenylenediamine. Examples of dicarboxylic acids include alkyl substituted or unsubstituted isophthalic acid, terephthalic acid, adipic acid, sebacic acid, butanedicarboxylic acid.

  Polyamides produced from aliphatic diamines and aliphatic dicarboxylic acids are traditional semi-crystalline polyamides (also called crystalline nylons) and not amorphous polyamides. Polyamides produced from aromatic diamines and aromatic dicarboxylic acids are difficult to process under general melt processing conditions.

  Therefore, an amorphous polyamide can be desirably produced when one of diamine and dicarboxylic acid is aromatic and the other is aliphatic. In this case, the aliphatic group of the amorphous polyamide is preferably an aliphatic group having 1 to 15 carbon atoms or an alicyclic alkyl group having 4 to 8 carbon atoms. The aromatic group of the amorphous polyamide is preferably a monocyclic or bicyclic aromatic group having a substituent having 1 to 6 carbon atoms. However, although amorphous polyamides as described above are not necessarily suitable for the present invention, for example, metaxylenediamine adipamide is easily crystallized under the heating conditions typical for thermoforming operations. Also, it is not desirable because it is crystallized when it is oriented.

  Specific examples of the amorphous polyamide suitable for the present invention include hexamethylenediamine isophthalamide / hexamethylenediamine isophthalamide / terephthalamide ternary having an isophthalic acid / terephthalic acid ratio of 99/1 to 60/40. Copolymers, mixtures of 2,2,4- and 2,4,4-trimethylhexamethylenediamine terephthalamide, isophthalic acid or terephthalic acid, or mixtures thereof with hexamethylenediamine or 2-methylpentamethylenediamine. Including polymers. Polyamides based on hexamethylenediamine isophthalamide / terephthalamide with a high terephthalic acid content are also useful, but in order to produce a processable amorphous polyamide, a second such as 2-methyldiaminopentane is used. Two diamines must be mixed.

  In the amorphous polyamide, a polymer based only on the monomer may contain a small amount of lactam species such as caprolactam or lauryl lactam as a comonomer. What is important is that the polyamide as a whole must be amorphous. Therefore, a small amount of the comonomer can be mixed unless crystallinity is imparted to the polyamide. Also, liquid or solid plasticizers such as glycerol, sorbitol or toluenesulfonamide (Sanizer 8, Monsanto) can be included in the amorphous polyamide at less than about 10% by weight. For most applications, the Tg of the amorphous polyamide (measured dry, ie, containing less than about 0.12% by weight moisture) is about 70 ° C to about 170 ° C, preferably about 80 ° C. It must be within the range of 160 ° C. Amorphous polyamides not specifically blended as described above have a Tg of approximately 125 ° C. when dried. The lower limit of Tg is not clear, and 70 ° C. is a general lower limit. The upper limit of Tg is not clear. However, if a polyamide having a temperature of about 170 ° C. or higher is used, it is not easily thermoformed. Accordingly, polyamides having aromatic groups in both the acid and amine moieties are too hot to be thermoformed due to their high Tg and are therefore generally unsuitable for the purposes of the present invention.

  The polyamide component also includes one or more semicrystalline polyamides. The term refers to traditional semi-crystalline polyamides, which are generally made with lactams or amino acids such as nylon 6 or nylon 11, or diamines such as hexamethylene diamine with succinic acid, Manufactured by condensation with adipic acid or a dibasic acid such as sebacic acid. Copolymers and terpolymers of the polyamide, for example, a copolymer of hexamethylenediamine / adipic acid and caprolactam (nylon 6, 66) are included. Mixtures of two or more crystalline polyamides can also be used. Both semicrystalline and amorphous polyamides are produced by condensation polymerization well known to those skilled in the art.

  The ionomer used in the present invention is preferably a copolymer of acrylic acid and ethylene, and the melt index is preferably in the range of 0.1 to 10 g / 10 min (190 ° C., 2,160 g). .

  The blocking nanocomposite is preferably included in an amount of 0.5 to 60 parts by weight, and more preferably 4 to 30 parts by weight. If the blocking nanocomposite is less than 0.5 parts by weight, the effect of improving the blocking property is small, and if it exceeds 60 parts by weight, the processing is not easy, and the physical properties of the molded product are deteriorated. Absent.

  It is a barrier nanocomposite and exhibits an excellent barrier effect so that the layered clay compound is finely peeled inside the barrier resin, which is a discontinuous phase. This is because the finely exfoliated layered clay compound forms a barrier film inside the barrier resin, and it plays an important role in improving the barrier properties and mechanical properties of the barrier resin itself. In addition, the effect of improving the barrier properties and mechanical properties of the composition itself is obtained. Therefore, in the present invention, the barrier resin and the layered clay compound are kneaded, the layered clay compound is dispersed in the nanometer size in the barrier resin, the contact area between the polymer chain and the layered clay compound is maximized, and the gas permeation rate is increased. Maximize the functions of suppression and liquid permeation suppression.

  The compatibilizing agent used in the present invention functions to improve the compatibility between the polyolefin resin and the blocking nanocomposite and form a composition having a stable structure.

  As the compatibilizing agent, it is desirable to use a hydrocarbon polymer containing a polar group. When a hydrocarbon-based polymer containing a polar group is used, the compatibilizer and polyolefin resin, and the compatibilizer and blocking resin nanocomposite are formed by the hydrocarbon polymer portion that is the base material of the polymer. Affinity is improved, and as a result, a stable structure is formed in the resulting resin composition.

  The compatibilizer is an epoxy-modified polystyrene copolymer, ethylene-ethylene anhydride-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-alkyl acrylate-acrylic acid copolymer, maleic anhydride-modified (graft) High density polyethylene, maleic anhydride modified (graft) linear low density polyethylene, ethylene-alkyl methacrylate-methacrylic acid copolymer, ethylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer, and maleic anhydride modified (graft) 1) One or more compositions selected from the group consisting of ethylene-vinyl acetate copolymers, or a mixture of these modifications can be used.

  The compatibilizer is preferably included in an amount of 1 to 30 parts by weight, and more preferably 2 to 15 parts by weight. If the compatibilizer is less than 1 part by weight, the mechanical properties of the molded product are poor at the time of molding the composition, and if it exceeds 30 parts by weight, the molding process of the composition is not easy and is not desirable.

  When the epoxy-modified polystyrene copolymer is used as a compatibilizing agent, a main chain containing 70 to 99 parts by weight of styrene and 1 to 30 parts by weight of an epoxy composition represented by the following chemical formula 1; A copolymer containing 1 to 80 parts by weight of an acrylic monomer is desirable:

  In Formula 1, R and R ′ are each independently the residue of an aliphatic compound having 1 to 20 carbon atoms or an aromatic compound having 5 to 20 carbon atoms having a double bond group at the end of the molecular structure. .

  The maleic anhydride-modified (graft) high-density polyethylene, maleic anhydride-modified (graft) linear low-density polyethylene, or maleic anhydride-modified (graft) ethylene-vinyl acetate copolymer is added to 100 parts by weight of the main chain. On the other hand, it is desirable to be composed of branches consisting of 0.1 to 10 parts by weight of maleic anhydride. If the content of maleic anhydride is less than 0.1 parts by weight, it is difficult to exert performance as a compatibilizing agent, and if it exceeds 10 parts by weight, it is desirable to give off a strange odor when molding the composition. Absent.

  The physical property reinforcing agent of the present invention may be at least one selected from LDPE, VLDPE, LLDPE and rubber. The rubber used as the physical property reinforcing agent is a conjugated diene such as polybutadiene, polyisoprene, butadiene-isoprene copolymer, polychloroprene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylate-butadiene copolymer. (Co) polymer, hydrogenated additive of such conjugated diene (co) polymer, olefin rubber such as ethylene-propylene copolymer, acrylic rubber such as polyacrylate, polyorganosiloxane, heat Examples thereof include a plastic elastic polymer, an ethylene-based ionomer copolymer, and the like, which are used alone or as a mixture of two or more. Among these, acrylic rubber, conjugated diene polymer, or hydrogenated additive of conjugated diene polymer is desirable.

  The acrylic rubber or conjugated diene polymer is produced by polymerizing monomers mainly composed of alkyl acrylate or conjugated diene composition. Such an acrylic rubber or conjugated diene polymer can be produced by copolymerizing not only the monomer but also other monofunctional polymerizable monomers, if necessary, Methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, benzyl methacrylate, naphthyl methacrylate, isobornyl methacrylate; aromatics such as styrene and α-methylstyrene Compounds; acrylonitrile and the like. The other monofunctional polymerizable monomer is desirably 20% by weight or less of the entire polymerizable monomer forming the rubber.

  The physical property reinforcing agent of the present invention is used in an amount of 1 to 10 parts by weight. If it is less than 1 part by weight, the desired physical property reinforcing effect cannot be obtained, and if it exceeds 10 parts by weight, the elasticity of the product increases and deformation easily occurs due to internal pressure.

During the production of the barrier nanocomposite composition of the present invention, dry blending (drive lending) is performed. This is because the pellet form barrier nanocomposite, the compatibilizing agent, the polyolefin, and the physical property reinforcing agent have a certain composition ratio. Means that the pellet mixer is simultaneously charged and mixed.
The composition produced as described above is dried and mixed and then molded to obtain a barrier pipe according to the present invention.

  At this time, as the molding method, general molding methods such as extrusion molding, compression molding, hollow molding and injection molding can be used.

  The barrier pipe of the present invention can be a single-layer molded product composed of the above-mentioned barrier nanocomposite composition, but a multilayer structure molding of the barrier nanocomposite composition layer and other thermoplastic resin layers. It is more desirable to use things. The resin that forms the thermoplastic resin layer adjacent to the barrier nanocomposite composition layer includes high density, medium density, or low density polyethylene; vinyl acetate, acrylate or butene, and α-olefins such as hexene. Polymerized ethylene copolymers; ionomer resins; propylene homopolymers or propylene copolymers copolymerized with α-olefins; polyolefins such as modified polypropylene blended with rubber polymers or anhydrous resins Mention may be made, as appropriate, of maleic acid-added or grafted thermoplastic resins. Examples of other resins constituting the thermoplastic resin layer include polyamide resins, polyester resins, polystyrene resins, polyvinyl chloride resins, acrylic resins, polyurethane resins, polycarbonate resins, and polyvinyl acetate resins. Can do.

  Moreover, it can also have an adhesive resin layer between the barrier nanocomposite composition layer constituting the multilayer of the pipe of the present invention and the thermoplastic resin layer adjacent thereto. Adhesive resins include unsaturated carboxylic acids or their anhydrides (such as maleic anhydride), olefin polymers or copolymers (eg, LLDPE, VLDPE, etc.), ethylene-vinyl acetate copolymers, ethylene- (meth). What was grafted to the acrylate copolymer can be mentioned as a typical example.

  The method for producing the pipe of the present invention is not particularly limited. For example, by using two or three extruders and a multi-layer circular die, endless pipes can be obtained most efficiently in a coextrusion molding operation.

  The layer configuration of the multilayer pipe is not particularly limited. When considering moldability and cost, thermoplastic resin layer / blocking nanocomposite composition layer / thermoplastic resin layer, blocking nanocomposite composition layer / adhesive resin layer / thermoplastic in order from outside to inside. Typical examples include resin layers, thermoplastic resin layers / adhesive resin layers / barrier nanocomposite composition layers / adhesive resin layers / thermoplastic resin layers. When a thermoplastic resin layer is disposed in both the outermost layer and the innermost layer, different resins can be used, and the same one can be used. Among these, it is particularly desirable to have a barrier nanocomposite composition layer / adhesive resin layer / thermoplastic resin layer configuration in order from the outside to the inside. In terms of gas barrier properties, it is particularly advantageous that the barrier nanocomposite composition layer is in the outermost layer of the pipe. However, the conventional EVOH multilayer resin is inferior in crack resistance, so even if a gas barrier resin is used for the outer layer, if cracks occur, it is a product for hot water circulation pipe due to deterioration in appearance and decrease in barrier properties. Value is significantly impaired. However, since the barrier nanocomposite composition used in the present invention is excellent in gas barrier properties and crack resistance, it provides a multilayer pipe for circulating hot water that does not generate cracks even if it is used in the outermost layer. it can.

  The single-layer and multilayer barrier pipes of the present invention are useful as hot water circulation pipes having excellent gas barrier properties and crack resistance. It can also be used as a pipe for various liquids or gases.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail through an Example, the following Example is for describing this invention, and does not intend to restrict | limit the scope of the present invention.

[Example]
Hereinafter, the materials used in the examples are as follows:
EVOH: E105B (Kuraray, Japan) used Nylon 6: EN500 (manufactured by KP Chemicals) HDPE-g-MAH: compatibilizer, PB3009 (CRAMPTON) used HDPE: RT DX800 (SK Chemicals)
Layered clay compound: Use Closite 30B (SCP) Thermal stabilizer: Use IR 1098 (Songwon Industry) Adhesive resin: Use AB130 (HDPE-g-MAH, LG Chem.)
Physical property reinforcing agent: EG8180 (ethylene octane copolymer) -Dupont-DOW

[Production Example 1 (Production of EVOH-layered clay compound nanocomposite)]
97% by weight of ethylene-vinyl alcohol copolymer (EVOH, E-105B (ethylene content 44 mol%), Nippon Kuraray Co., Ltd., melt index: 5.5 g / 10 min, density: 1.14 g / cm ³ ) Montmorillonite (US / Southern Cray Products, C2OA), 3 wt%, which was put into a main hopper of a twin screw extruder (SM PLATEK, co-rotating twin screw extruder, φ40) and organized as a layered clay compound, and the ethylene -0.1 parts by weight of thermal stabilizer IR 1098 is separately fed into the side feeder with respect to 100 parts by weight of the vinyl alcohol copolymer and organic montmorillonite added, and then the ethylene-vinyl alcohol copolymer / A layered clay compound nanocomposite was prepared in pellet form. At this time, the extrusion temperature was 180-190-200-200-200-200-200 ° C., the screw speed was 300 rpm, and the discharge conditions were 15 kg / hr.

[Production Example 2 (Nylon 6-layered clay compound nanocomposite production)]
97% by weight of polyamide (nylon 6) was charged into a main hopper of a twin screw extruder (SM PLATEK, co-rotating twin screw extruder, φ40), and 3% by weight of montmorillonite organized as a layered clay compound and the polyamide After adding 0.1 parts by weight of thermal stabilizer IR 1098 to the side feeder with respect to 100 parts by weight of the total amount of montmorillonite and organic montmorillonite, a nanocomposite of polyamide / layered clay compound is produced in a pellet form did. At this time, the extrusion temperature was 220-225-245-245-245-245-245 ° C., the screw speed was 300 rpm, and the discharge conditions were 40 kg / hr.

[Example 1]
15 parts by weight of EVOH nanocomposite prepared in Preparation Example 1, 10 parts by weight of compatibilizing agent, 72 parts by weight of HDPE, and 3 parts by weight of physical property reinforcing agent were mixed in a dry mixer (Myeongwoo powder system, Double cone mixer, MYDCM- 100) and dried and mixed for 30 minutes, and then charged into the main hopper of a single screw extruder (Goeffert φ45, L / D: 23) at a processing temperature of 190-210-210-210-210 ° C. A single-layer pipe having an outer diameter of 30 mm was manufactured under a processing condition of a speed of 20 rpm and a discharge speed of 6 kg / hr.

[Example 2]
15 parts by weight of nylon 6 nanocomposite produced in Production Example 2, 10 parts by weight of compatibilizing agent and 72 parts by weight of HDPE, and 3 parts by weight of physical property reinforcing agent were mixed in a dry mixer (Myeongwoo Powder System, Double cone mixer, MYDCM- 100), and after 30 minutes of dry mixing, it is put into the main hopper of a single screw extruder (Goeffert φ45) at a processing temperature of 210-220-220-220-222 ° C, and the screw speed is 20 rpm. A single-layer pipe having an outer diameter of 30 mm was manufactured.

[Example 3]
15 parts by weight of the nylon 6 nanocomposite produced in Production Example 2 is a belt-type feeder (K-TRON No. 1), 10 parts by weight of the compatibilizer is a belt-type feeder (K-TRON No. 2), 72 weights of high-density polyethylene. Part is a belt-type feeder (K-TRON No. 3), and 3 parts by weight of physical properties reinforcing agent is dry mixed in the main hopper of a single-screw extruder (Goetfert φ45) via a belt-type feeder (K-TRON No. 4) At a processing temperature of 210-220-220-220-222 ° C. and a screw speed of 20 rpm, a single-layer pipe having an outer diameter of 30 mm was manufactured.

[Example 4]
After 15 parts by weight of EVOH nanocomposite produced in Production Example 1, 10 parts by weight of compatibilizer, 72 parts by weight of HDPE and 3 parts by weight of physical property reinforcing agent were dry-mixed using a tumble mixer, this mixture was mixed with three parts. The outer layer extruder (outside layer extruder) of the layer (3-layer) pipe extruder, HDPE for the inner layer extruder, adhesive resin for the intermediate layer extruder, and a multilayer pipe with an outer diameter of 30 mm Produced.

[Example 5]
After 4 parts by weight of the nylon 6 nanocomposite prepared in Production Example 2, 2 parts by weight of a compatibilizer, 93 parts by weight of HDPE, and 1 part by weight of a physical property reinforcing agent were dry-mixed using a tumble mixer, this mixture was mixed. An outer layer extruder of a three-layer pipe extruder was introduced, HDPE was introduced into the inner layer extruder, and an adhesive resin was introduced into the intermediate layer extruder to produce a multilayer pipe having an outer diameter of 30 mm.

[Example 6]
After 15 parts by weight of the nylon 6 nanocomposite prepared in Preparation Example 2, 10 parts by weight of a compatibilizing agent, 72 parts by weight of HDPE and 3 parts by weight of a physical property reinforcing agent were dry-mixed using a tumble mixer, this mixture was mixed. An outer layer extruder of a three-layer pipe extruder was introduced, HDPE was introduced into the inner layer extruder, and an adhesive resin was introduced into the intermediate layer extruder to produce a multilayer pipe having an outer diameter of 30 mm.

[Example 7]
34 parts by weight of the nylon 6 nanocomposite produced in Production Example 2, 18 parts by weight of a compatibilizing agent, 40 parts by weight of HDPE, and 8 parts by weight of a physical property reinforcing agent were dry-mixed using a tumble mixer, and then the mixture. Was introduced into an outer layer extruder of a three-layer pipe extruder, HDPE was introduced into the inner layer extruder, and an adhesive resin was introduced into the intermediate layer extruder to produce a multilayer pipe having an outer diameter of 30 mm.

[Comparative Example 1]
A single layer pipe was produced by extruding 100% by weight of high density polyethylene.

[Comparative Example 2]
A pipe was manufactured in the same manner as in Example 1 except that the layered clay compound was not used.

[Comparative Example 3]
A pipe was manufactured in the same manner as in Example 2 except that the layered clay compound was not used.

[Comparative Example 4]
In place of the barrier nanocomposite composition, EVOH is introduced into the outer layer extruder of the three-layer pipe extruder, HDPE is introduced into the inner layer extruder, adhesive resin is introduced into the intermediate layer extruder, and the outer diameter is 30 mm. A multilayer pipe was manufactured.

  The obtained pipe was evaluated for oxygen barrier properties and crack resistance by the following methods.

[Oxygen barrier test]
The oxygen barrier property is evaluated based on the increasing rate of dissolved oxygen (DO). The slower the DO increase rate, the better the oxygen barrier property. The obtained pipe is filled with metallic tin and the water from which DO is removed is circulated, and the DO increase rate in water is measured under the conditions of 20 ° C. and 65% RH. The DO increase rate is expressed in μg / hr and represents that DO increases at a rate of μg / hr per liter of water in the pipe. That is, when the volume of water in the entire system including a pipe is V1cc, the volume of water in the pipe is V2cc, and the oxygen concentration increase rate of circulating water in the apparatus per unit time is B (μg / hr), The DO increase rate A (μg / hr) is represented by a value calculated by A = B (V1 / V2).

[Crack resistance]
The obtained pipe was cut into 20 cm and left in a thermostatic box at −15 ° C. for 10 minutes, and then the inner diameter of the pipe was reduced to 45 mm with a metal enlarger having four claw-shaped parts at one end of the pipe Slowly divide into 4 times until it becomes. Next, it is observed with the naked eye whether cracks are generated in the blocking resin layer. Such a test is carried out using 100 pipe samples, and evaluation is made based on the following crack generation frequency (occurrence rate) of the A stage to the D stage.
A: No cracks are generated B: Fine cracks (0.5 mm or less) are generated C: Fine cracks and large cracks (0.5 mm or more) are generated D: Only large cracks are generated

  As can be seen from Table 1 and Table 2, it was found that the pipes according to the examples were superior in barrier properties and crack resistance compared to the pipes of the comparative examples.

  The pipe of the present invention has excellent barrier properties, and is effective as an automobile filler pipe, an air conditioner pipe, an LNG pipe, and the like.

  Although the present invention has been described using the embodiments, they are merely illustrative, and various changes and modifications can be made by those skilled in the art without departing from the scope and spirit of the present invention. You can understand that there is. Accordingly, the technical scope of the present invention should not be determined by the described embodiments but by the claims.

Claims (18)

(A) 40 to 98 parts by weight of a polyolefin resin;
(B) A barrier nanocomposite of one or more barrier resins selected from the group consisting of ethylene-vinyl alcohol copolymer (EVOH), polyamide, ionomer and polyvinyl alcohol (PVA) and a layered clay compound. 5 to 60 parts by weight,
(C) 1 to 30 parts by weight of a compatibilizer;
(D) 1 to 10 parts by weight of one or more physical property reinforcing agents selected from low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE) and rubber are dry mixed. Barrier pipe manufactured by molding the composition.   The polyolefin resin (a) is selected from the group consisting of high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene-propylene copolymer, metallocene polyethylene and polypropylene. The barrier pipe according to claim 1, wherein the barrier pipe is a seed or more.   The polypropylene is one or more selected from the group consisting of a propylene homopolymer or copolymer, a metallocene polypropylene, and a composite resin obtained by adding talc or a flame retardant to a propylene homopolymer or copolymer. 2. Barrier pipe according to 2.   The weight ratio of the blocking resin to the layered clay compound in the blocking nanocomposite is 58.0: 42.0 to 99.9: 0.1. Blocking pipe.   The layered clay compound is montmorillonite, bentonite, kaolinite, mica, hectorite, hectorite fluoride, saponite, bidelite, nontronite, stevensite, vermiculite, halosite, vorconsky stone, sacconite, magadite and Kenya. The blocking pipe according to claim 1, which is at least one selected from the group consisting of lights.   2. The barrier pipe according to claim 1, wherein the layered clay compound contains 1 to 45% by weight of an organic agent in the layered clay compound.   The organic substance containing any one functional group selected from the group consisting of primary to quaternary ammonium, phosphonium, maleate, succinate, acrylate, benzylic hydrogen, oxazoline and dimethyl distearyl ammonium The barrier pipe according to claim 6, wherein:   The barrier pipe according to claim 1, wherein the ethylene-vinyl alcohol copolymer has an ethylene content of 10 to 50 mol%.   The polyamide is 1) nylon 4.6, 2) nylon 6, 3) nylon 6.6, 4) nylon 6.10, 5) nylon 7, 6) nylon 8, 7) nylon 9, 8) nylon 11, 9) Nylon 12, 10) Nylon 46, 11) MXD6, 12) Amorphous polyamide, 13) Copolyamide having two or more components among polyamides of 1) to 12), or 14) 1) to 12) The barrier pipe according to claim 1, which is a mixture of two or more polyamides.   The barrier pipe according to claim 9, wherein the amorphous polyamide has a glass transition temperature of about 70C to 170C.   The amorphous polyamide is hexamethylenediamine isophthalamide, a hexamethylenediamine isophthalamide / terephthalamide terpolymer having an isophthalic acid / terephthalic acid ratio of 99/1 to 60/40, 2,2,4- And a mixture of 2,4,4-trimethylhexamethylenediamine terephthalamide, and a copolymer of isophthalic acid or terephthalic acid, or a mixture thereof, and hexamethylenediamine or 2-methylpentamethylenediamine. The barrier pipe according to claim 9.   The barrier pipe according to claim 11, wherein the amorphous polyamide is a hexamethylenediamine isophthalamide / terephthalamide terpolymer having an isophthalic acid / terephthalic acid ratio of about 70/30.   The barrier pipe according to claim 1, wherein the ionomer has a melt index in the range of 0.1 to 10 g / 10 min (190 ° C, 2,160 g).   The rubber includes a conjugated diene (co) polymer, a hydrogenated additive of a conjugated diene (co) polymer, an olefin rubber, an acrylic rubber, a polyorganosiloxane, a thermoplastic elastic polymer, and an ethylene ionomer copolymer. The barrier pipe according to claim 1, wherein the pipe is one or more selected from the group consisting of coalesces.   The compatibilizer is ethylene-ethylene anhydride-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-alkyl acrylate-acrylic acid copolymer, maleic anhydride modified (graft) high density polyethylene, maleic anhydride modified. From (graft) linear low density polyethylene, ethylene-alkyl methacrylate-methacrylic acid copolymer, ethylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer and maleic anhydride modified (graft) ethylene-vinyl acetate copolymer It is 1 or more types selected from the group which consists of, The interruption | blocking pipe of Claim 1 characterized by the above-mentioned.   The barrier pipe according to claim 1, which is manufactured by extrusion molding, compression molding, hollow molding or injection molding.   The barrier pipe according to claim 1, wherein the pipe has a single-layer or multi-layer structure.   The blocking pipe according to claim 1, wherein the pipe is a hot water circulation pipe, an automobile filler pipe, an air conditioner pipe, or an LNG pipe.