JP2023121393A - Silane crosslinkable resin composition, silane crosslinked resin molding, method for producing them, and silane crosslinked resin molded product - Google Patents

Abstract

To provide a silane crosslinkable resin composition which enables production of a silane crosslinked resin molding that exhibits high flowability in melting while containing a polybutene resin, has excellent appearance, is flexible and is excellent in high temperature characteristics, and a method for producing the same; the silane crosslinked resin molding and a method for producing the same; and a silane crosslinked resin molded product.SOLUTION: There are provided a silane crosslinkable resin composition which contains 100 pts.mass of a base resin containing 5-50 mass% of a polybutene resin, 1-30 mass% of an ethylene-α-olefin copolymer rubber, 5-40 mass% of a styrenic elastomer, and 5-40 mass% of mineral oil, a silane coupling agent grafted and coupled to the base resin, 0.5-50 pts.mass of an inorganic filler, and 0.01-0.5 pt.mass of a silanol condensation catalyst, and a method for producing the same; a silane crosslinked resin molding using the silane crosslinkable resin composition and a method for producing the same; and a silane crosslinked resin molded product containing the silane crosslinked resin molding.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a silane-crosslinkable resin composition, a silane-crosslinked resin molded article, a method for producing the same, and a silane-crosslinked resin molded article using the silane-crosslinked resin molded article.

As a coating layer for wiring materials such as insulated wires, cables, cords, optical fiber core wires or optical fiber cords (optical fiber cables) used in the electric and electronic equipment fields and industrial fields, and for water supply or hot water supply (water supply, drainage ), various (tubular) resin moldings are applied as tubular bodies (sometimes referred to as water supply tubular bodies) such as hoses or tubes. These resin moldings are required to have properties according to their applications. For example, the coating materials and tubular bodies described above are required to have appearance properties, flexibility, heat resistance, and the like. Furthermore, chlorine water resistance is required for the inner layer of the tubular body for tap water that comes into contact with tap water. Polyolefin resins such as polyethylene resins and polypropylene resins are generally used as materials for forming such resin molded bodies. A polybutene resin that is excellent in resistance to chlorine water is preferably used. However, although polybutene resin is amorphous immediately after molding, it undergoes crystal transition with the passage of time and eventually becomes a crystalline resin with a 1/3 helical structure. , stiff and may not exhibit the required flexibility.

Resin moldings (tubular bodies for waterworks) have been proposed to improve such low flexibility caused by hard polybutene resins. For example, in Patent Document 1, an inner layer tube having a polybutene resin layer or a crosslinked polyethylene resin layer as an inner layer that is in direct contact with water and a thermoplastic elastomer layer as an outer layer, and a reinforcing layer that covers the outer side. home is described. In addition, Patent Document 2 describes "A hot water supply hose having a four-layer structure consisting of an inner layer, an intermediate layer, a reinforcing layer, and an outer layer in order from the inside, wherein the inner layer is a crosslinked polyethylene resin or polybutene resin, the intermediate layer is a polypropylene resin, A resin containing an ethylene-based elastomer and/or a styrene-based elastomer, the reinforcing layer being a braided layer or spiral wound layer made of metal wire or synthetic fiber, and the outer layer being a polypropylene resin and an ethylene-based elastomer and/or a styrene-based elastomer. A hot water supply hose characterized by being a resin containing.

JP-A-9-178058 JP 2010-131875 A

Both of the hoses described in Patent Documents 1 and 2 improve flexibility of the hose as a whole by providing a layer formed of a thermoplastic elastomer layer or the like on the outside of an inner layer formed of polybutene resin. However, since the inner layer itself of these hoses is formed of a hard polybutene resin, there is still room for improvement in the flexibility of the hose as a whole.

By the way, as a method of molding a resin into a tubular shape, for example, an extrusion molding method in which a resin is extruded into a tubular shape is extruded into a strand such as a tape, a cord or a sheet, and then spirally wound. , a so-called spiral molding method, and the like. Moreover, when it is desired to further impart pressure resistance, it may be reinforced with a hard resin (for example, a polypropylene resin, a nylon resin, or the like). If the hard resin is made into a strand (string) and can be spiral-molded together with the flexible tape-shaped resin, both pressure resistance and excellent flexibility can be achieved, so the spiral molding method is preferably employed. However, polybutene resins are not suitable for spiral molding because they have poor fluidity when melted compared to general polyolefin resins (eg, polyethylene resins). Specifically, when polybutene resin is extruded into a tape-shaped, string-shaped, or sheet-shaped molded body (hereinafter sometimes referred to as a tape-shaped molded body), flow marks remain, and granules due to aggregates occur and the appearance Appearance defects such as roughness (occurrence of undulations) are likely to occur. Even if the tape-shaped molded article can be molded while suppressing the appearance defect, when the tape-shaped molded article is spirally wound to form a tubular body, the tape-shaped molded articles cannot be fused together with sufficient strength. . Therefore, even if such a tubular compact maintains its shape in a low-temperature environment such as room temperature, it deforms significantly in a high-temperature environment of, for example, 80° C. or higher, and may even form a spiral shape. The fused portion of the tape-shaped molded body wound around the tape peels off (becomes unable to maintain its shape) and ceases to function as a tubular molded body. Since the hoses described in Patent Documents 1 and 2 have a multi-layered structure, no consideration has been given to manufacturing them by a spiral molding method. be done.

The present invention solves the above problems, exhibits high fluidity when melted while containing polybutene resin, has excellent appearance, is flexible, and has high temperature characteristics that maintain its shape even in a high temperature environment. An object of the present invention is to provide a silane-crosslinkable resin composition capable of producing an excellent silane-crosslinked resin molded article, and a method for producing the same. Further, the present invention aims to provide a silane crosslinked resin molded article which has an excellent appearance, is flexible and has excellent high-temperature properties while containing a polybutene resin, and a method for producing the silane crosslinked resin molded article. Make it an issue. A further object of the present invention is to provide a silane-crosslinked resin molded article using the silane-crosslinked resin molded article exhibiting the above excellent properties.

The present inventors have found that a crosslinkable resin composition containing polybutene resin as an essential component is obtained by mixing (coexisting) ethylene-α-olefin copolymer rubber, styrene-based elastomer and mineral oil with polybutene resin at specific content ratios. ) to form a base resin, and then combine a specific amount of inorganic filler and a silanol condensation catalyst to form a silane-crosslinkable resin composition, thereby exhibiting high fluidity when melted and preventing the occurrence of poor appearance. It was found that it can be molded while suppressing it (excellent moldability). Furthermore, the present inventors have found that when this silane-crosslinkable resin composition is used as a material for producing a silane-crosslinkable resin molded article, excellent appearance and high-temperature properties can be obtained by utilizing high fluidity and excellent moldability when melted. It has been found that a flexible silane crosslinked resin molded article can be produced while having Based on this knowledge, the present inventors have made further studies and completed the present invention.

That is, the object of the present invention has been achieved by the following means.
<1> 100 parts by mass of a base resin containing 5 to 50% by mass of polybutene resin, 1 to 30% by mass of ethylene-α-olefin copolymer rubber, 5 to 40% by mass of styrene elastomer, and 5 to 40% by mass of mineral oil; , a silane coupling agent grafted to the base resin, 0.5 to 50 parts by mass of an inorganic filler, and 0.01 to 0.5 parts by mass of a silanol condensation catalyst. .
<2> The silane crosslinkable resin composition according to <1>, wherein the base resin contains 12 to 40% by mass of the polybutene resin.
<3> The silane crosslinkable resin composition according to <1> or <2>, wherein the polybutene resin has a melt flow rate (190° C., 2.16 kg) of 0.3 to 2 g/10 minutes.
<4> The silane according to any one of <1> to <3>, wherein the inorganic filler is at least one selected from metal hydrates, talc, clay, silica, calcium carbonate and carbon black. A crosslinkable resin composition.
<5> The silane crosslinkable resin composition according to any one of <1> to <4>, wherein the content of the silane coupling agent is 3 to 15 parts by mass with respect to 100 parts by mass of the base resin. .
<6> A silane-crosslinked resin molded article obtained by molding the silane-crosslinkable resin composition according to any one of <1> to <5> above and then bringing the composition into contact with water.
<7> A silane-crosslinked resin molded article comprising the silane-crosslinked resin molded article according to <6> above.
<8> The silane crosslinked resin molded article according to <7>, which is a hose or tube.
<9> The silane-crosslinked product of <8>, wherein the hose or tube is formed by contacting water with the spiral molded product of the silane-crosslinkable resin composition of any one of <1> to <5>. Resin molded product.

<10> 100 parts by mass of base resin containing 5 to 50% by mass of polybutene resin, 1 to 30% by mass of ethylene-α-olefin copolymer rubber, 5 to 40% by mass of styrene elastomer, and 5 to 40% by mass of mineral oil On the other hand, 0.5 to 50 parts by mass of an inorganic filler, 1 to 15 parts by mass of a silane coupling agent having a graft reaction site capable of grafting to the base resin, and 0.01 to 0.01 part of an organic peroxide. A method for producing a silane crosslinkable resin composition, comprising the step (1) of melt-mixing 6 parts by mass and 0.01 to 0.5 parts by mass of a silanol condensation catalyst to obtain a silane crosslinkable resin composition. hand,

The step (1) includes the following steps (a) and (c), provided that when a part of the base resin is melt-mixed in the following step (a), the following steps (a) and ( A method for producing a silane crosslinkable resin composition comprising b) and step (c).
Step (a): All or part of the base resin, the inorganic filler, and the silane cup
The ring agent and the organic peroxide are heated at a temperature equal to or higher than the decomposition temperature of the organic peroxide.
Step (b): Melt-mixing the remainder of the base resin and the silanol condensation catalyst to form a catalyst masterbatch.
Process for preparing a starbatch Step (c): the silane masterbatch and the silanol condensation catalyst or the catalyst master
-The process of melting and mixing the batch

<11> The step (1), the step (2) of obtaining a molded article by molding the silane crosslinkable resin composition, and the step (3) of bringing the molded article into contact with water to obtain a silane crosslinked resin molded article. ), a method for producing a silane crosslinked resin molded product.
<12> The method for producing a silane-crosslinked resin molded article according to <11>, wherein the step (2) of obtaining the molded article is a step of spiral-molding the silane-crosslinkable resin composition to obtain a tubular molded article.

In the present invention, a numerical range represented using "to" means a range including the numerical values described before and after "to" as lower and upper limits. In the present invention, when multiple numerical ranges are set for the content, physical properties, etc. of a component, the upper limit and lower limit forming the numerical range are described before and after "-" as a specific numerical range. It is not limited to a specific combination, and can be a numerical range in which the upper limit value and the lower limit value of each numerical range are appropriately combined.

The present invention provides a silane-crosslinkable resin composition that exhibits high fluidity when melted while containing a polybutene resin, has an excellent appearance, and is capable of producing a silane-crosslinkable resin molded article that is flexible and has excellent high-temperature properties. , and a method for producing the same. Further, the present invention can provide a silane crosslinked resin molded article which has an excellent appearance, is flexible and has excellent high-temperature properties while containing a polybutene resin, and a method for producing the silane crosslinked resin molded article. Furthermore, the present invention can provide a silane-crosslinked resin molded article using the silane-crosslinked resin molded article exhibiting the above excellent properties.

[Silane crosslinkable resin composition]
The silane crosslinkable resin composition of the present invention contains 5 to 50% by mass of polybutene resin, 1 to 30% by mass of ethylene-α-olefin copolymer rubber, 5 to 40% by mass of styrene elastomer, and 5 to 40% by mass of mineral oil. 100 parts by mass of a base resin containing a base resin, a silane coupling agent grafted to the base resin, 0.5 to 50 parts by mass of an inorganic filler, and 0.01 to 0.5 parts by mass of a silanol condensation catalyst are doing. This silane crosslinkable resin composition is prepared, for example, by the method for producing a silane crosslinkable resin composition of the present invention, which will be described later.
Although the details will be described later, in the silane crosslinkable resin composition of the present invention, a silane coupling agent bound or dissociated with an inorganic filler is grafted to a base resin, particularly an ethylene-α-olefin copolymer rubber (grafting reaction). It contains a silane crosslinkable resin and a decomposition product of polybutene resin. This silane-crosslinkable resin composition exhibits high fluidity when melted, and the silane-crosslinkable resin molded article exhibiting excellent properties described later is formed by the silane-crosslinking method (silanol condensation reaction), for example, volatilization of the silane coupling agent. It is possible to manufacture while suppressing the occurrence of appearance defects and the like. Therefore, the silane crosslinkable resin composition of the present invention is suitably used in the method for producing the silane crosslinked resin molded article of the present invention or the silane crosslinked resin molded article of the present invention.

The details of why the silane-crosslinkable resin composition of the present invention exhibits the above-described excellent properties are not yet clear, but are considered as follows.
The silane crosslinkable resin composition of the present invention contains a polybutene resin as a polymer component constituting the base resin, and a grafting reaction of the silane coupling agent to the base resin, which is peculiar to the silane crosslinking method. At times, it is believed to also contain decomposed polybutene resin decomposed by radicals generated from organic peroxides. Thus, by making the silane crosslinkable resin composition crosslinkable, the decomposition product of the polybutene resin can be coexisted (contained) in the composition, and high fluidity can be expressed at the time of melting. is considered possible.
Examples of the decomposition product of polybutene resin include polybutene resin having a low molecular weight (for example, 10,000 or less), and alkenes such as pentene and hexene. The content of the polybutene resin in the silane crosslinkable resin composition (base resin) means the total content of the polybutene resin and its decomposition products, and the amount used in the preparation of the silane crosslinkable resin composition (in the base resin content of polybutene resin). The content of the decomposed product in the silane crosslinkable resin composition cannot be uniquely determined according to the fluidity to be expressed, but for example, the content of the polybutene resin in the silane crosslinkable resin composition (base resin) and , and the later-described content of the organic peroxide used during the grafting reaction.

Further, the silane-crosslinkable resin composition of the present invention contains ethylene-α-olefin copolymer rubber as a polymer component constituting the base resin. As a result, a silane cross-linked structure can be constructed in the ethylene-α-olefin copolymer rubber via the silane coupling agent, and in cooperation with the polybutene resin (including decomposition products) and the styrene elastomer, etc., the above-mentioned It is believed that a silane-crosslinked resin molded article exhibiting excellent properties can be molded. Further, the silane crosslinkable resin composition of the present invention contains a styrene-based elastomer and mineral oil as polymer components constituting the base resin. This is thought to reinforce the development of flexibility of the silane-crosslinked resin molded article and the suppression of appearance defects. Furthermore, the silane crosslinkable resin composition exhibits excellent high-temperature properties without impairing fluidity, flexibility, etc., by containing an inorganic filler.

[Silane cross-linked resin molding]
The silane-crosslinked resin molded article of the present invention is a crosslinked resin molded article (made of a silanol condensate of the silane-crosslinkable resin composition) obtained by subjecting the silane-crosslinkable resin composition of the present invention to silane crosslinking (silanol condensation reaction) after molding. molded body). The silane-crosslinked resin molded article of the present invention is flexible, has high bending resistance, and exhibits an excellent appearance. In addition, since the silane crosslinked structure is formed not only in a room temperature environment but also without a special crosslinking treatment, a large tension is applied, for example, in the longitudinal direction in a high temperature environment of, for example, 80 to 100°C. Also, the amount of deformation is small, and high temperature characteristics (also called heat resistance and temperature dependence) are excellent.
Although details will be described later, the silane-crosslinked resin molded article of the present invention has a crosslinked structure in which the base resin, usually an ethylene-α-olefin copolymer rubber, is silane-crosslinked (a crosslinked structure via a silane coupling agent or a silanol condensate thereof). )have. This crosslinked structure may incorporate an inorganic filler, as described later.
The silane-crosslinked resin molded article of the present invention is molded into an appropriate shape and size according to its use, for example, the use of the silane-crosslinked resin molded article of the present invention, which will be described later.

Each component used in the present invention is described below.
Each component can use 1 type(s) or 2 or more types, respectively.
In the present invention, the term "resin" includes elastomers and rubbers unless otherwise specified.
<Base resin>
The base resin used in the present invention contains polybutene resin, ethylene-α-olefin copolymer rubber, styrene elastomer, and mineral oil as essential polymer components. When the base resin contains these polymer components, it is possible to form a silane-crosslinked resin molded article that exhibits high fluidity when melted, has excellent appearance and high-temperature properties, and has high flexibility.
In addition to the essential polymer components described above, the base resin may be any polyolefin resin other than polybutene resin and other than ethylene-α-olefin copolymer rubber, and further any rubber or elastomer such as a polymer forming this polyolefin resin. It can contain a polymeric component.

(polybutene resin)
Polybutene resins include 1-butene homopolymer or copolymer resins, and examples thereof include highly stereoregular crystalline resins obtained by polymerizing high-purity butene-1 with a Ziegler catalyst. . By using polybutene resin in combination with ethylene-α-olefin copolymer rubber, styrene elastomer and mineral oil in the silane cross-linking method, high fluidity can be expressed in the silane cross-linkable resin composition, and appearance and flexibility can be improved. and high-temperature properties can be formed.
The copolymerization component capable of forming the polybutene resin may be any compound that can be copolymerized with 1-butene, and examples thereof include compounds having an ethylenically unsaturated bond, and more specifically, compounds other than 1-butene. and olefin compounds.
The melt flow rate (MFR) of the polybutene resin is not particularly limited, but from the viewpoint of the fluidity of the silane crosslinkable resin composition, it is preferably 0.3 to 2 g/10 minutes, and 0.8 to 2.0 g. /10 minutes is more preferred. In the present invention, the MFR of polybutene resin refers to a value measured under the conditions of a temperature of 190° C. and a load of 2.16 kg in accordance with Japanese Industrial Standards (JIS) K 7210-1 (2014).
The polybutene resin may be appropriately synthesized, and commercially available products can be used. Commercially available products include Beuron (registered trademark) and Tafmer (registered trademark) manufactured by Mitsui Chemicals, Inc.

(Ethylene-α-olefin copolymer rubber)
Ethylene-α-olefin copolymer rubber (also referred to as ethylene rubber in the present invention) is not particularly limited as long as it is a copolymer rubber obtained by copolymerizing ethylene and α-olefin, and known rubbers are used. can do. The ethylene-α-olefin copolymer rubber has a site capable of grafting reaction with the grafting reaction site of the silane coupling agent, and undergoes the grafting reaction with the silane coupling agent in the silane crosslinking method. Sites capable of grafting reactions include, for example, unsaturated bond sites of carbon chains and carbon atoms having hydrogen atoms. By using ethylene-α-olefin copolymer rubber in combination with polybutene resin, styrene elastomer and mineral oil, it is possible to form a silane-crosslinkable resin composition, which has excellent appearance, flexibility and high-temperature properties. A silane crosslinked resin molding can be formed.
The ethylene-α-olefin copolymer rubber preferably includes a two-component copolymer rubber of ethylene and an α-olefin, a terpolymer rubber of ethylene, an α-olefin and a diene compound, and the like. The α-olefin is not particularly limited, and α-olefins having 3 to 12 carbon atoms are preferred. Further, the diene compound constituting the terpolymer is not particularly limited, and examples thereof include conjugated diene compounds such as butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, dicyclo Examples include non-conjugated diene compounds such as pentadiene (DCPD), ethylidene norbornene (ENB), and 1,4-hexadiene, and non-conjugated diene compounds are preferred. Ethylene-propylene rubber (EPM) is preferred as the bi-copolymer rubber, and ethylene-propylene-diene rubber (EPDM) is preferred as the terpolymer rubber.

(Styrene-based elastomer)
A styrene-based elastomer refers to an elastomer composed of a polymer having a component derived from an aromatic vinyl compound in its molecule. By using a styrene-based elastomer in combination with polybutene resin, ethylene-α-olefin copolymer rubber, and mineral oil, the silane-crosslinkable resin composition can exhibit high fluidity. The silane cross-linking structure can be uniformly constructed, and the appearance and flexibility can be improved. Examples of such styrene-based elastomers include block copolymers and random copolymers of conjugated diene compounds and aromatic vinyl compounds, or hydrogenated products thereof. More specifically, styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-styrene block copolymer (SIS), hydrogenated SIS, styrene-butadiene-styrene block copolymer (SBS) , hydrogenated SBS, styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-butadiene rubber (SBR), hydrogenated styrene-butadiene Rubber (HSBR) etc. are mentioned.

(mineral oil)
The mineral oil may be any petroleum-derived oil, and includes oils used as plasticizers for polyolefin resins or mineral oil softeners for rubber. Mineral oil softener is a mixed oil containing three of oils consisting of hydrocarbons having aromatic rings, oils consisting of hydrocarbons having naphthenic rings, and oils consisting of hydrocarbons having paraffin chains. By using mineral oil in combination with polybutene resin, ethylene-α-olefin copolymer rubber and styrenic elastomer, the silane-crosslinkable resin composition can exhibit high fluidity. The silane cross-linking structure can be uniformly constructed, and the appearance and flexibility can be improved. As the mineral oil, paraffin oil and naphthenic oil are preferably used, and paraffin oil is particularly preferably used. This mineral oil is preferably included especially with the elastomer.

(polyolefin resin)
The polyolefin resin that can be contained in the base resin may be any polyolefin resin other than the above-mentioned polybutene resin and other than the above-mentioned ethylene-α-olefin copolymer rubber, and may be a polymer obtained by homopolymerizing or copolymerizing an olefin compound. Examples thereof include known resins used in resin compositions.
Specific examples include resins such as polyethylene (PE), polypropylene (PP), and polyolefin copolymers having an acid copolymerization component or an acid ester copolymerization component. As the polyolefin resin, polyethylene resin and polypropylene resin are preferable. The polyolefin resin may be acid-modified with a commonly used unsaturated carboxylic acid or derivative thereof.

Polyethylene resin (PE) is not particularly limited as long as it is a polymer resin containing ethylene as a main component. Examples thereof include high density polyethylene (HDPE), low density polyethylene (LDPE), ultra high molecular weight polyethylene (UHMW-PE), linear low density polyethylene (LLDPE) and very low density polyethylene (VLDPE) resins.
The MFR of the polyethylene resin is not particularly limited, but is preferably 0.1 to 10 g/10 min, more preferably 1 to 5 g/10 min, from the viewpoint of fluidity of the silane crosslinkable resin composition. . In the present invention, the MFR of a polyethylene resin refers to a value measured in accordance with JIS K 7210-1 (2014) under conditions of a temperature of 190° C. and a load of 2.16 kg.

Polypropylene resin (PP) is not particularly limited as long as it is a polymer resin containing a propylene component as a main component. Examples thereof include propylene homopolymers, random polypropylene resins and block polypropylene resins.
The MFR of the polypropylene resin is not particularly limited, but is preferably 0.1 to 50 g/10 min, more preferably 1 to 30 g/10 min, in terms of fluidity of the silane crosslinkable resin composition. . In the present invention, the MFR of a polypropylene resin refers to a value measured in accordance with JIS K 7210-1 (2014) under conditions of a temperature of 230° C. and a load of 2.16 kg.

The compound leading to the acid copolymerization component or the acid ester copolymerization component in the polyolefin copolymer resin having the acid copolymerization component or the acid ester copolymerization component is not particularly limited, and includes carboxylic acid compounds such as (meth)acrylic acid. , and acid ester compounds such as vinyl acetate and alkyl (meth)acrylate. The alkyl group of alkyl (meth)acrylate preferably has 1 to 12 carbon atoms.
Polyolefin copolymers having an acid copolymer component or an acid ester copolymer component include, for example, ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer, polymer (EEA), ethylene-butyl acrylate copolymer (EBA).

(Composition of base resin)
The base resin contains the polymer components at the following content so that the total is 100% by mass. When the base resin contains a plurality of each polymer component, the content of the polymer component is the total content of the polymer components.
The content of the polybutene resin in 100% by mass of the base resin is 5 to 50% by mass. When the content of the polybutene resin is within the above range, the fluidity of the silane-crosslinked resin composition can be enhanced, and the appearance, flexibility and high-temperature properties of the silane-crosslinked resin molded article can be improved. The content of polybutene resin is preferably 10 to 45% by mass in terms of improving fluidity, appearance, flexibility and high-temperature properties in a well-balanced manner at a higher level, and in terms of exhibiting high strength. It is more preferably up to 40% by mass, and even more preferably 17 to 35% by mass.
The content of the ethylene-α-olefin copolymer rubber in 100% by mass of the base resin is 1 to 30% by mass. When the content of the ethylene-α-olefin copolymer rubber is within the above range, it is possible to improve the appearance, flexibility and high-temperature properties of the silane-crosslinked resin molded article while maintaining the fluidity of the silane-crosslinked resin composition. The content of the ethylene-α-olefin copolymer rubber can improve the flexibility and high-temperature properties of the silane-crosslinked resin molding in a well-balanced manner by constructing the silane-crosslinked structure while maintaining an excellent appearance. , preferably 3 to 25% by mass, more preferably 5 to 20% by mass.

The content of the styrene-based elastomer in 100% by mass of the base resin is 5 to 40% by mass. When the content of the styrene-based elastomer is within the above range, the fluidity of the silane-crosslinkable resin composition can be enhanced, and the appearance, flexibility and high-temperature properties of the silane-crosslinkable resin molded article can be improved. The content of the styrene-based elastomer is preferably 7 to 35% by mass, more preferably 10 to 30% by mass, in terms of further enhancing fluidity, appearance and flexibility. .
The content of mineral oil in 100% by mass of the base resin is 5 to 40% by mass. When the content of the mineral oil is within the above range, the fluidity of the silane-crosslinked resin composition can be enhanced, and the appearance, flexibility and high-temperature properties of the silane-crosslinked resin molded article can be improved. The mineral oil content is preferably 7 to 35% by mass, more preferably 10 to 30% by mass, in terms of further enhancing fluidity, appearance and flexibility. .
The total content of the styrene-based elastomer and mineral oil in 100% by mass of the base resin is preferably 10 to 70% by mass, particularly 15 to 60% by mass, in terms of improving fluidity and appearance. %, more preferably 20 to 50% by mass.

The total content of the polyolefin resin in 100% by mass of the base resin is not particularly limited and is appropriately determined. For example, it is preferably 2 to 30% by mass, more preferably 3 to 25% by mass, even more preferably 5 to 20% by mass.
The content of the polyethylene resin in 100% by mass of the base resin is not particularly limited, and is appropriately set in consideration of the total content of the polyolefin resin. 0.5 to 15% by mass is more preferable. Similarly, the content of the polypropylene resin in 100% by mass of the base resin is not particularly limited, and is appropriately set in consideration of the total content of the polyolefin resin, and may be, for example, 2 to 25% by mass. Preferably, it is 5 to 20% by mass. The content of the polyolefin copolymer resin having the ethylene-α-olefin copolymer and the acid copolymer component or the acid ester copolymer component in 100% by mass of the base resin is not particularly limited, and the total content of the above polyolefin resin is not particularly limited. The amount is appropriately set in consideration of the amount, and can be, for example, 0 to 20% by mass.

<Silane coupling agent>
The silane crosslinkable resin composition contains a silane coupling agent grafted onto a base resin, especially an ethylene-α-olefin copolymer rubber. The base resin to which the silane coupling agent is grafted is preferably prepared by a grafting reaction between the silane coupling agent and the base resin in step (a) described below.
The silane coupling agent used in the present invention (before the grafting reaction) is a grafting reaction capable of grafting to a graftable site of the base resin in the presence of radicals generated by decomposition of the organic peroxide. It has sites (atoms or functional groups such as ethylenically unsaturated groups). Moreover, it preferably has a hydrolyzable silyl group as a reaction site capable of silanol condensation and can react with a site capable of chemical bonding of the inorganic filler. Silane coupling agents that can be used in the present invention are not particularly limited, and include silane coupling agents used in conventional silane cross-linking methods.
The silane coupling agent preferably includes a silane coupling agent having an ethylenically unsaturated group and a hydrolyzable silyl group, specifically vinyltrimethoxysilane, vinyltriethoxysilane, vinyltributoxysilane, vinylalkoxysilanes such as vinyldimethoxyethoxysilane, vinyldimethoxybutoxysilane, vinyldiethoxybutoxysilane, allyltrimethoxysilane, allyltriethoxysilane, vinyltriacetoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, Examples include (meth)acryloxyalkoxysilanes such as methacryloxypropylmethyldimethoxysilane. Among them, vinyltrimethoxysilane or vinyltriethoxysilane is particularly preferred.

<Inorganic filler>
The inorganic filler is not particularly limited, but preferably has a site on its surface that can be chemically bonded to a silanol-condensable reaction site of a silane coupling agent through a hydrogen bond, a covalent bond, or an intermolecular bond. The site that can be chemically bonded to the reaction site of the silane coupling agent is not particularly limited, but examples thereof include OH groups (hydroxyl groups, water molecules containing water or water of crystallization, OH groups such as carboxyl groups), amino groups, SH groups, and the like. be done.
Specific examples of inorganic fillers include aluminum hydroxide, magnesium hydroxide, boehmite, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, and aluminum borate. , whiskers, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, hydrotalcite, talc, and other compounds having a hydroxyl group or water of crystallization. Boron nitride, silica (crystalline silica, amorphous silica, etc.), carbon black, clay (fired clay), zinc oxide, tin oxide, titanium oxide, molybdenum oxide, silicone compounds, quartz, zinc borate, white carbon , zinc borate, zinc hydroxystannate, zinc stannate and the like. The inorganic filler preferably contains at least one of metal hydrate, talc, clay, silica, calcium carbonate and carbon black.
A surface-treated inorganic filler surface-treated with a silane coupling agent or the like can be used as the inorganic filler. Although the amount of the surface treatment is not particularly limited, it is preferably 3% by mass or less, for example.

<Silanol condensation catalyst>
The silanol condensation catalyst has the function of causing (promoting) a condensation reaction in the presence of water at the reaction site capable of silanol condensation of the silane coupling agent grafted to the base resin. Based on the action of this silanol condensation catalyst, the base resin is crosslinked via the silane coupling agent.
Such silanol condensation catalysts are not particularly limited, and examples thereof include organotin compounds, metallic soaps, platinum compounds and the like. Examples of organic tin compounds include organic tin compounds such as dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctiate, and dibutyltin diacetate.

<Additive>
In the present invention, various additives commonly used in resin compositions can also be used. Such additives include, for example, antioxidants, lubricants, metal deactivators, plasticizers, flame retardants, flame retardant aids, and (co)polymers other than those described for the base resin. .
Examples of antioxidants include hindered phenol-based antioxidants and benzimidazole-based antioxidants. Flame retardants (auxiliaries) include brominated flame retardants and/or antimony trioxide.

<Organic Peroxide>
In the present invention, an organic peroxide is used in preparing the silane crosslinkable resin composition.
The organic peroxide generates radicals through thermal decomposition, thereby causing a grafting reaction of the silane coupling agent to the base resin. It has a function of promoting a covalent bond forming reaction, which is also referred to as a (radical) addition reaction, and a function of causing a decomposition reaction of the polybutene resin. The organic peroxide is not particularly limited, and examples thereof include general formulas: R ¹ -OO-R ² , R ³ -OO-C(=O)R ⁴ , R ⁵ C(=O)-OO(C= O) A compound represented by ^R6 is preferably used. Here, R ¹ to R ⁶ each independently represent an alkyl group, an aryl group or an acyl group. Among R ¹ to R ⁶ of each compound, it is preferable that all of them are alkyl groups, or that one of them is an alkyl group and the rest are acyl groups.
The decomposition temperature of the organic peroxide is preferably 80 to 195°C, particularly preferably 125 to 180°C, as measured by the method described in JP-A-2016-121203.
Examples of such organic peroxides include organic peroxides described in paragraph [0036] of JP-A-2016-121203. Incorporated as part of the description. Among them, dicumyl peroxide, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane (Perhexa 25B), 2,5-dimethyl-2,5-di-(tert-butylperoxy ) hexyne-3 is preferred.

(Composition of silane crosslinkable resin composition)
In the silane crosslinkable resin composition, the content of the silane coupling agent grafted to the base resin (the content in terms of mass before the grafting reaction to the base resin) is not particularly limited. It is possible to produce a silane crosslinked resin molded product with excellent appearance and a sufficient crosslinked structure by suppressing the formation of protruding aggregates (gel lumps) caused by gels and volatilization of the silane coupling agent. It is preferably 1 to 15 parts by mass, more preferably 2 to 15 parts by mass, even more preferably 3 to 15 parts by mass, and 3 to 8 parts by mass with respect to 100 parts by mass of the resin. is particularly preferred.
The content of the inorganic filler in the silane-crosslinkable resin composition is 100 parts by mass of the base resin in that it can improve the fluidity of the silane-crosslinkable resin composition and the flexibility and high-temperature characteristics of the silane-crosslinked resin molded product. 0.5 to 50 parts by mass, preferably 1 to 40 parts by mass, more preferably 3 to 30 parts by mass.
The content of the silanol condensation catalyst in the silane crosslinkable resin composition is 0.01 to 0.5 parts by mass with respect to 100 parts by mass of the base resin in terms of achieving a good balance between appearance, flexibility, and high-temperature properties. parts, preferably 0.03 to 0.2 parts by mass, more preferably 0.05 to 0.15 parts by mass.

The total content of the additives in the silane crosslinkable resin composition is not particularly limited, and can be appropriately set within a range that does not impair the effects of the present invention. For example, the content of the antioxidant is not particularly limited, but is preferably 0.2 to 8 parts by mass, more preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of the base resin. .

(Composition of silane crosslinked resin molding)
The silane-crosslinked resin molded article is formed by molding a silane-crosslinkable resin composition and then bringing it into contact with water for a silanol condensation reaction. It becomes the same as the content in the crosslinkable resin composition. However, in the case of the silane crosslinked resin molding, the content of the silane coupling agent is the content before the silanol condensation reaction, and the content of the base resin is the content before the crosslinking.

[Method for producing silane cross-linkable resin composition and silane cross-linked resin molding]
The method for producing the silane crosslinkable resin composition of the present invention and the method for producing the silane crosslinked resin molding of the present invention are described below.
The silane-crosslinkable resin composition of the present invention is produced by performing the following step (1), and the silane-crosslinked resin molded article of the present invention is produced by performing the following steps (1) to (3).
The method for producing a silane-crosslinked resin molded article and the method for producing a silane-crosslinkable resin composition of the present invention may be collectively referred to as the production method of the present invention.

Step (1): 5 to 50% by mass of polybutene resin, 1 to 3 of ethylene-α-olefin copolymer rubber
0% by mass, 5 to 40% by mass of styrene elastomer, and 5 to 5% mineral oil
0.5 to 0.5 parts of inorganic filler for 100 parts by mass of base resin containing 40% by mass
50 parts by mass, 1 to 15 parts by mass of a silane coupling agent, and 0.5 parts by mass of an organic peroxide.
01 to 0.6 parts by mass and 0.01 to 0.5 parts by mass of a silanol condensation catalyst are dissolved.
Melt mixing to obtain a silane crosslinkable resin composition

This step (1) has the following steps (a) and (c). However, when melting and mixing a part of the base resin in the following step (a), the following steps (a), (b) and (c) are included.
Step (a): all or part of a base resin, an inorganic filler, and a silane coupling agent
and an organic peroxide are melt-mixed at a temperature equal to or higher than the decomposition temperature of the organic peroxide
to prepare a silane masterbatch Step (b): Melting and mixing the rest of the base resin and the silanol condensation catalyst to obtain a catalyst master
- Step of preparing a batch Step (c): Silane masterbatch and silanol condensation catalyst or catalyst masterbatch
A step of melting and mixing

Step (2): Step of molding the silane-crosslinkable resin composition to obtain a molded article Step (3): Step of contacting the molded article with water to obtain a silane-crosslinked resin molded article

In the manufacturing method of the present invention, the mixing amount of each polymer component used as the base resin is the same as the above-mentioned content rate explained as the composition of the base resin. Also, the amounts of the silane coupling agent, inorganic filler, silanol condensation catalyst, and additives to be mixed are the same as those in the silane crosslinkable resin composition described above.
In the production method of the present invention, when part of the base resin is mixed in step (a), the polymer component to be mixed may be a specific polymer component, or two or more polymer components. good too. The ratio of the base resin to be mixed in step (a) is preferably 60 to 95% by mass, preferably 70 to 85% by mass, of 100% by mass of the base resin to be mixed in step (a) and step (b). It is more preferable to have The rest of the base resin (carrier resin) mixed in step (b) is appropriately determined according to the portion of the base resin mixed in step (a).

However, in the production method of the present invention, the base resin used in step (a) contains at least polybutene resin and ethylene-α-olefin copolymer rubber among the above polymer components. As a result, the fluidity of the silane-crosslinkable resin composition can be increased, and a silane-crosslinked structure is constructed in the silane-crosslinked resin molding (forming an ethylene-α-olefin copolymer rubber grafted with a silane coupling agent). can.
The amount of the polybutene resin used in the step (a) is not particularly limited, but from the viewpoint of fluidity, it is preferably 50% by mass or more, and 75% by mass, based on the content of the polybutene resin in the base resin. % or more, more preferably 100% by mass (total amount).
The amount of the ethylene-α-olefin copolymer rubber used in the step (a) is not particularly limited. It is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, based on the content of the polymerized rubber.

At least part of the styrene-based elastomer and mineral oil is preferably used in the step (a) from the viewpoint of improving fluidity and appearance of the silane crosslinked resin composition. The amount of each of the styrene-based elastomer and mineral oil used in step (a) is not particularly limited, but for example, it is preferably 50% by mass or more, preferably 70% by mass, relative to each content in the base resin. It is more preferable to make it 80 mass % or more, and it is still more preferable to make it 80 mass % or more. The total amount of the styrene-based elastomer and mineral oil used in step (a) is not particularly limited, and can be determined within the same range as the amounts used above.

Although a part of the inorganic filler can be used in step (b), it is preferably used in step (a) in terms of improving high-temperature characteristics. When an inorganic filler is used in step (b), the amount used is not particularly limited and can be determined as appropriate.

Various additives may be mixed in either step (a) or step (b).
The antioxidant may be mixed in either step (a) or step (b), but mixing in step (b) makes the grafting reaction in step (a) efficient It is preferable in that it can be advanced.

The amount of the organic peroxide to be mixed in step (a) is 0.01 to 0.6 parts by mass with respect to 100 parts by mass of the base resin. When the organic peroxide is mixed in the above content with the polybutene resin and ethylene-α olefin copolymer rubber contained in the above content, the polybutene resin decomposes during melt mixing and the ethylene-α olefin copolymer rubber is formed. The grafting reaction of the silane coupling agent can be caused (promoted) in a well-balanced manner, and the occurrence of gel spots can be suppressed. As a result, the fluidity of the silane-crosslinkable resin composition can be increased, and the appearance, flexibility and high-temperature properties of the silane-crosslinkable resin molded article can be improved. The amount of the organic peroxide to be mixed is preferably 0.1 to 0.2 parts by mass.

<Step (a)>
In the step (a), a base resin and a silane coupling agent are subjected to a graft reaction in the presence of an inorganic filler to obtain a silane crosslinkable resin in which the silane coupling agent is grafted to the base resin and a decomposition product of the polybutene resin. and a step of preparing a silane masterbatch (silane MB).
In this step, the base resin is heated and mixed with the inorganic filler and the silane coupling agent in the presence of the organic peroxide at a temperature higher than the decomposition temperature of the organic peroxide. This gives the silane MB as a molten mixture.

In the step (a), the mixing temperature for melt-mixing (also referred to as melt-kneading) the above components is the decomposition temperature of the organic peroxide or higher, preferably the decomposition temperature of the organic peroxide + (25 to 110) ° C. temperature, more preferably 150 to 230°C, still more preferably 175 to 210°C. Mixing conditions such as mixing time can be appropriately set. For example, the mixing time can be 1-25 minutes, preferably 3-20 minutes. By melt-mixing at a temperature equal to or higher than the decomposition temperature of the organic peroxide, the organic peroxide thermally decomposes to generate radicals, thereby promoting the grafting reaction and the decomposition reaction of the polybutene resin.

As a mixing method, any method generally used for mixing rubbers and plastics may be used. As the mixing apparatus, for example, a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer or various kneaders are used, and closed mixers such as a Banbury mixer or various kneaders are preferred.

In the present invention, the order of mixing is not specified, and the above components may be mixed in any order. For example, the above ingredients can be melt mixed together.
In the production method of the present invention, step (a) is preferably mixed in the following mixing order by following steps (a-1) and (a-2).

Step (a-1): A step of mixing an inorganic filler and a silane coupling agent to prepare a mixture
Process step (a-2): The mixture obtained in step (a-1) and a part of the base resin are mixed with an organic peracid
It is melt-mixed at a temperature above the decomposition temperature of the organic peroxide in the presence of the organic peroxide.
process

In step (a-1), by pre-mixing the inorganic filler and the silane coupling agent, the silane coupling agent bonded or adsorbed to the inorganic filler with a weak bond and the silane coupling agent bonded or adsorbed to the inorganic filler with a strong bond. A ring agent can be formed in a well-balanced manner. This can effectively prevent volatilization of the silane coupling agent and further condensation reaction between non-adsorbed silane coupling agents during melt mixing in step (a-2). As a result, it is possible to produce a silane-crosslinked resin molded article having a more excellent appearance and further improved mechanical properties (tensile strength) and heat resistance attributed to the silane-crosslinking method. Here, examples of the weak bond with the inorganic filler include interaction due to hydrogen bonding, interaction between ions, partial charges or dipoles, action due to adsorption, and the like. Further, examples of the strong bond with the inorganic filler include chemical bonding with a chemically bondable site on the surface of the inorganic filler.

The mixing method and mixing conditions of the step (a-1) are not particularly limited, but usually at a temperature lower than the decomposition temperature of the organic peroxide, preferably 10 to 60° C., more preferably 10 to 60° C., using a known mixer. A method and conditions of dry or wet mixing at about room temperature (20 to 25° C.) for several minutes to several hours can be mentioned. Above all, dry mixing (dry blending) at a temperature lower than the decomposition temperature of the organic peroxide is preferred. Other conditions for dry mixing are determined appropriately.

In step (a-1), the base resin can be mixed as long as the temperature is maintained below the decomposition temperature.
The organic peroxide may be present during the melt mixing in step (a-2) and may be mixed in step (a-2), but should be mixed in step (a-1). is preferred.

Next, the mixture obtained in step (a-1) and part of the base resin are melt-mixed in the presence of an organic peroxide at a temperature equal to or higher than the decomposition temperature of the organic peroxide to obtain a silane MB. is prepared (step (a-2)). Thus, a silane masterbatch containing the silane crosslinkable resin and the decomposition product of the polybutene resin is prepared. In the melt-mixing in this step, it is possible to prevent excessive cross-linking reaction (generation of gel lumps) between the base resins while suppressing volatilization and self-condensation of the above-described silane coupling agent.
The melt-mixing method and conditions of this step (a-2) are not particularly limited, and the melt-mixing method and conditions of the step (a) can be applied.

In the step (a-2), at least the following are conceivable modes of grafting reaction of the silane coupling agent to the base resin. That is, it is a mode in which the silane coupling agent bound or adsorbed to the inorganic filler by a weak bond desorbs from the inorganic filler and undergoes a grafting reaction with the base resin. From this aspect, the crosslinked structure formed in step (3) to be described later does not incorporate an inorganic filler, and usually becomes a crosslinked structure via a silanol condensate between silane coupling agents. Moreover, it is a mode in which the silane coupling agent bonded or adsorbed to the inorganic filler by a strong bond undergoes a grafting reaction to the resin while maintaining the bond or adsorption to the inorganic filler. From this aspect, the crosslinked structure formed in step (3) to be described later incorporates the inorganic filler, and becomes a crosslinked structure via the silane coupling agent bonded to the inorganic filler as a starting point.

Antioxidants, additives and the like can also be mixed in step (a). However, it is preferred that substantially no silanol condensation catalyst is mixed in step (a). Thereby, the occurrence of the silanol condensation reaction of the silane coupling agent can be suppressed. In the present invention, the phrase "substantially not mixed" does not mean that the presence of a silanol condensation catalyst that is inevitably present is not excluded. It means that it may be present as long as it is in the range of 01 parts by mass or less.

The silane MB prepared in step (a) contains a reaction mixture of a base resin, an inorganic filler, and a silane coupling agent. contains a silane crosslinkable resin (silane graft polymer) grafted to the The silane coupling agent grafted to the base resin includes those bonded or adsorbed to the inorganic filler at its silanol-condensable reaction sites.
The MFR of the silane MB is not particularly limited, but is preferably 0.3 g/10 minutes or more, more preferably 0.3 to 20 g/10 minutes, from the viewpoint of the fluidity of the silane crosslinkable resin composition. Preferably, it is more preferably 0.8 to 15 g/10 minutes. In the present invention, the MFR of silane MB refers to a value measured in accordance with JIS K 7210-1 (2014) under conditions of a temperature of 190° C. and a load of 2.16 kg.
The silane MB is preferably pelletized or powdered.

<Step (b)>
In the production method of the present invention, the remainder of the base resin and the silanol condensation catalyst are melt-mixed to prepare a catalyst masterbatch (catalyst MB).
The melt-mixing method and conditions in step (b) are not particularly limited, and the melt-mixing method and conditions in step (a) can be applied. For example, the melt-mixing temperature may be higher than the melting temperature of the base resin, preferably 120 to 200°C, more preferably 140 to 180°C.
Catalyst MB is preferably in the form of pellets or powder.

<Step (c)>
In the production method of the present invention, the silane masterbatch and the silanol condensation catalyst or catalyst masterbatch are then melt-mixed. Preferably, the silane MB and the catalyst MB are melt-mixed.
The mixing method is not particularly limited, but is basically the same as the melt mixing in step (a), and mixing is performed at a temperature at which at least the base resin melts. The mixing conditions in step (c) are not particularly limited, and the mixing conditions in step (a) above can be applied. For example, the mixing temperature is appropriately selected according to the base resin, and is preferably 80 to 250°C, more preferably 100 to 240°C, and even more preferably 120 to 200°C.
In the melt-mixing of step (c), a melt-mixing method and conditions capable of maintaining the fluidity (moldability) of the silane crosslinkable resin composition are set. The silane crosslinkable resin in the silane crosslinkable resin composition is an uncrosslinked body in which the silane coupling agent is not silanol-condensed. Practically, partial cross-linking (partial cross-linking) is unavoidable when melted and mixed in the step (c), but the resulting silane cross-linkable resin composition is assumed to retain moldability. For example, in order to avoid the occurrence or progress of the silanol condensation reaction, it is preferable that the silane MB and the silanol condensation catalyst are not kept in a mixed state at a high temperature for a long time.
In step (c), the silane MB and the silanol condensation catalyst or catalyst masterbatch are preferably dry blended prior to melt mixing. The dry blending method and conditions are not particularly limited, and examples thereof include the dry blending in step (a-1) and its conditions.

Thus, the silane crosslinkable resin composition of the present invention is produced.
This silane crosslinkable resin composition contains a silane crosslinkable resin, a decomposition product of polybutene resin, an inorganic filler, a silanol condensation catalyst, and the like. In this silane crosslinkable resin, the silanol-condensable reaction site of the silane coupling agent may be bonded to or adsorbed to the inorganic filler, but is not silanol-condensed. Therefore, the silane crosslinkable resin is composed of a silane crosslinkable resin in which a silane coupling agent bonded or adsorbed to an inorganic filler is grafted to a base resin, and a silane coupling agent that is not bonded or adsorbed to an inorganic filler in a base resin. and a grafted silane crosslinkable resin.

<Step (2)>
In the method for producing a silane-crosslinked resin molded article of the present invention, the silane-crosslinked resin composition is then molded to obtain a molded article.
The molding method is not particularly limited, and is appropriately selected according to the form of the desired product. Examples of the molding method include extrusion molding using an extruder, extrusion molding using an injection molding machine, molding using other molding machines, and spiral molding described later. When manufacturing wiring materials, extrusion molding is preferable from the viewpoint of productivity and co-extrusion with conductors. The details of the spiral molding method will be described later, but usually, after molding the silane crosslinkable resin composition into a tape, string, sheet, or the like, the tape-shaped molding is spirally wound to form a tubular shape. how to do
Molding conditions (melt-mixing conditions) are not particularly limited as long as they can be uniformly mixed and molded, and the silane-crosslinkable resin composition of the present invention is not subject to a silanol condensation reaction. The melt mixing method and conditions of c) can be applied.

Step (2) can be performed simultaneously with step (c) or sequentially. For example, the silane MB and the catalyst MB are dry blended immediately before or in the coating device (extruder), melt-mixed in the coating device (step (c)), and then formed on the outer peripheral surface of the conductor or the like. A series of steps (co-extrusion) can be employed.

<Step (3)>
In the method for producing a silane crosslinked resin molded article of the present invention, the molded article obtained in step (2) is then brought into contact with water to produce a silane crosslinked resin molded article. Since the molded product obtained in the step (2) is an uncrosslinked product, this step causes a silanol condensation reaction at the reaction site capable of silanol condensation of the silane coupling agent grafted to the base resin, Let it proceed (promote) and finally silane cross-link.
Contact between the uncrosslinked molded article and water can be carried out by a usual method. Although the silanol condensation reaction proceeds by simply leaving it in a temperature environment of normal temperature, for example, about 20 to 25° C., it is preferable to actively contact with water to accelerate the silanol condensation reaction (crosslinking reaction). As the contact method, methods (conditions) normally applied to the silane cross-linking method can be mentioned. For example, each contact method such as immersion in warm water, introduction into a moist heat bath, exposure to high temperature steam, etc. can be applied. .

Thus, the silane-crosslinked resin molded article of the present invention is produced.
This silane crosslinked resin molding contains a crosslinked resin obtained by condensing a base resin (particularly, an ethylene-α-olefin copolymer rubber) via siloxane bonds, and a decomposition product of a polybutene resin. In addition, the silane crosslinked resin molding contains an inorganic filler, and this inorganic filler may be bonded to the silane coupling agent of the crosslinked resin. Therefore, the crosslinked resin is composed of a plurality of base resins bonded or adsorbed to the inorganic filler by the silane coupling agent, and a crosslinked resin bonded (crosslinked) via the inorganic filler and the silane coupling agent, and a grafted bond to the base resin. The hydrolyzable groups of the silane coupling agent are hydrolyzed and undergo a silanol condensation reaction with each other, thereby forming a crosslinked resin that is crosslinked through the silane coupling agent (siloxane bond) (without an inorganic filler). considered to contain.

In the production method of the present invention, in the step (a), the decomposition reaction of the polybutene resin and the grafting reaction of the silane coupling agent are suppressed, the volatilization and self-condensation reaction of the silane coupling agent, and the cross-linking reaction between the base resins are suppressed. can be caused (promoted) by Therefore, the silane-crosslinkable resin composition of the present invention exhibits good fluidity, has excellent appearance and high-temperature properties, and can be used to produce flexible silane-crosslinkable resin molded articles.

[Silane cross-linked resin molding]
The silane-crosslinked resin molded article of the present invention is a product containing the silane-crosslinked resin molded article of the present invention, and includes various resin molded articles. Examples thereof include insulated wires, covering materials for cables or optical fiber cables, materials for rubber-substitute wires and cables, heat-resistant parts for microwave ovens or gas ranges, heat-resistant wire parts, heat-resistant sheets, heat-resistant films, and the like. In addition, power plugs, connectors, sleeves, boxes, tape substrates, tubes, sheets, packing, cushioning materials, anti-vibration materials, wiring materials used for internal wiring and external wiring of electric and electronic equipment, especially electric wires and optical fiber cables, Furthermore, the above-mentioned wiring material and a tubular molding are mentioned.
The silane-crosslinked resin molded article of the present invention may be a molded article containing the silane-crosslinked resin molded article of the present invention in a part (resin molded portion) thereof, and the silane-crosslinked resin molded article of the present invention alone may be a molded article. It may be a molded product.
Like the silane crosslinked resin molded article of the present invention, the silane crosslinked resin molded article of the present invention is flexible and highly flexible, and exhibits excellent appearance and high-temperature properties. Furthermore, even in a high-temperature environment, the spiral-molded silane-crosslinked resin molded product can maintain its function as a molded product because the fused portion of the tape-shaped molded product is not easily peeled off. The silane-crosslinked resin molded article of the present invention is preferably used as a wiring material or a tubular molded article, more preferably as a tubular article for water supply, and tubularly molded for hot water supply (for example, heat resistance of 100 ° C.) by utilizing the above characteristics. It is more preferable to use it as a body.

A wiring material and a tubular molded article that are preferable as the silane-crosslinked resin molded article of the present invention will be described.
<Wiring material>
The wiring material is a wiring material having a coating layer on the outer periphery of a conductor, and the coating layer is formed into an annular layer by forming the silane crosslinkable resin composition of the present invention into a ring-shaped layer and crosslinked to obtain the silane crosslinked material of the present invention. A wiring material formed of a resin molded body is mentioned.
The wiring material is the same as those commonly used in various electric/electronic equipment fields and industrial fields, except that the coating layer is formed of the silane crosslinked resin molding of the present invention. The coating layer formed of the silane crosslinked resin molded article of the present invention is provided directly on the outer peripheral surface of the conductor or via another layer, and depending on the type, application, required characteristics, etc. of the wiring material, another layer may be provided. The presence/absence, materials, etc. are appropriately determined. Usual conductors can be used, for example, copper or aluminum single wires or stranded wires (tensile fibers are tandemly arranged or twisted together). In addition to bare wires, tin-plated wires or wires having an enamel-coated insulating layer can also be used. The thickness of the coating layer formed from the silane-crosslinked resin molded article of the present invention is not particularly limited, but is usually about 0.15 to 5 mm.
The wiring material of the present invention can be produced by contacting water after molding by various molding methods in the step (2). Preferably, it can be produced by arranging the silane crosslinkable resin composition of the present invention on the outer periphery of the conductor in a ring shape, followed by a crosslinking reaction (silanol condensation reaction). For example, in the above-described method for producing a silane-crosslinked resin molded article of the present invention, the molding step (2) is performed by co-extrusion molding the silane-crosslinkable resin composition on the outer periphery of the conductor using a coating device (extruder). It can be manufactured by setting it as a process. Specific coextrusion molding is as described above.

<Tubular shaped body>
The tubular molded body is not particularly limited as long as it has a tubular structure, and examples include various hoses and tubes. A hose or tube for water supply, particularly hot water supply, is preferable as the tubular molded body in that the above-described excellent properties can be utilized. The tubular molded article may have a single-layer structure consisting only of a constituent layer formed of the silane-crosslinked resin molded article of the present invention, or may have a multi-layer structure having this constituent layer and a layer formed of another material. There may be. Layers formed of other materials include various layers that are commonly applied to tubular molded articles, such as reinforcing layers, surface layers, and layers described in the above-mentioned patent documents. When the silane-crosslinkable resin composition of the present invention is used to produce a tubular molded article, it is possible to produce a constituent layer (tubular molded article) having a single-layer structure that exhibits high flexibility while containing a polybutene resin. As described in the above patent document, it is not necessary to have a multi-layered structure in order to exhibit flexibility, and production efficiency and production cost can be reduced.
The tubular molded article (constituent layer) produced by the spiral molding method is a silanol condensate (silane In general, a spiral seam portion (fused portion) formed by fusion bonding of the silane crosslinkable resin composition of the present invention remains as a molding trace.
The outer diameter, inner diameter, diameter difference (thickness of the tube wall), length and the like of the entire tubular molded article are not particularly limited and are appropriately determined according to the application. For example, the outer diameter can be 2-100 mm, the inner diameter can be 1-80 mm, the diameter difference can be 0.5-10 mm, and the length can be 0.1-100 m. be able to. In addition, the outer diameter, inner diameter, diameter difference (thickness of the tube wall), length, and the like of the tubular molded article (constituent layer) formed from the silane crosslinked resin molded article of the present invention are appropriately determined. , for example, the outer diameter can be 1.5-90 mm, the inner diameter can be 1-80 mm, the diameter difference can be 0.25-5 mm, and the length can be 0.1-100 m can be

The tubular molded body can be produced by various molding methods in the above step (2). Preferably, the silane crosslinkable resin composition of the present invention is formed into a tape, string or sheet by various molding methods (preferably extrusion molding), and then the tape-shaped molding is formed into a helical (spiral) shape. ) to form a tubular body (corresponding to the above step (2)) by a spiral molding method, and finally bringing it into contact with water to produce a tubular molded body (corresponding to the above step (3)). In the spiral molding method, when spirally winding, the edges of the tape-shaped molded body are overlapped and the tape-shaped molded body is fused in the width direction. The overlapping amount (width) is not particularly limited as long as it can be fused with sufficient strength, and is determined as appropriate. For example, it can be 0.5 to 30 mm. Since the silane crosslinkable resin composition of the present invention has excellent fluidity and can be rapidly molded into a tape-shaped molded article (while maintaining the melting temperature), the overlapped ends of the tape-shaped molded article are Spontaneously fused by heat (heating temperature during melt molding). Therefore, by using the silane-crosslinkable resin composition of the present invention, it is possible to produce a tubular molded article that is strongly fused by spiral molding while containing a polybutene resin that is hard and unsuitable for spiral molding. As the spiral forming method, a conventional method, for example, a method using a hose manufacturing apparatus having a hose forming shaft capable of rotating and feeding while spirally winding a tape-shaped molded article can be applied. The spiral molding conditions can be appropriately determined according to the application, etc. For example, the pitch during winding can be 10 to 150 mm. The conditions for molding the tape-shaped molded article are set so that the silane crosslinkable resin composition of the present invention does not undergo a silanol condensation reaction.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is not limited to these.

Compounds used in Examples and Comparative Examples are shown below.
<Base resin>
(1) Polybutene resin: Beuron (registered trademark) P5050N (trade name, MFR (190°C, 2.16 kg) 0.5 g/10 min, manufactured by Mitsui Chemicals, Inc.)
(2) Polybutene resin: Toughmer (registered trademark) BL4000 (trade name, MFR (190°C, 2.16 kg) 1.8 g/10 min, manufactured by Mitsui Chemicals, Inc.)
(3) Linear low-density polyethylene resin: Sumikasen CU5003 (trade name, MFR (190°C, 2.16 kg) 0.4 g/10 minutes, manufactured by Sumitomo Chemical Co., Ltd.)
(4) Linear low-density polyethylene resin: Evolue SP1071C (trade name, MFR (190°C, 2.16 kg) 10 g/10 min, manufactured by Prime Polymer Co., Ltd.)
(5) Linear low-density polyethylene: Evolue SP0540 (trade name, MFR (190°C, 2.16 kg) 3.8 g/10 minutes, manufactured by Prime Polymer Co., Ltd.)
(6) Polypropylene resin: PB222A (trade name, random PP, MFR (230°C, 2.16 kg) 0.8 g/10 minutes, manufactured by SunAllomer)
(7) Polypropylene resin: PM921V (trade name, random PP, MFR (230°C, 2.16 kg) 25 g/10 minutes, manufactured by SunAllomer)
(8) Polypropylene resin: PM940M (trade name, random PP, MFR (230°C, 2.16 kg) 30 g/10 minutes, manufactured by SunAllomer)
(9) Ethylene-α olefin rubber: Nordel 4770P (trade name, EPDM, manufactured by Dow)
(10) Ethylene-α olefin rubber: EPT3092PM (trade name, EPDM, manufactured by Mitsui Chemicals, Inc.)
(11) Styrene-based elastomer: Tuftec N504 (trade name, SEBS, manufactured by Asahi Kasei Corporation)
(12) Mineral oil: Cosmo Neutral 500 (trade name, paraffin oil, manufactured by Cosmo Oil Lubricants)

<Inorganic filler>
(1) Inorganic filler: Softon 1200 (trade name, calcium carbonate, manufactured by Bihoku Funka Kogyo Co., Ltd.)
(2) Inorganic filler: Aerosil 200 (trade name, silica, manufactured by Nippon Aerosil Co., Ltd.)

<Silane coupling agent>
KBM-1003: trade name, vinyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd. <Silanol condensation catalyst>
ADEKA STAB OT-1: trade name, dioctyltin dilaurate, manufactured by ADEKA <organic peroxide>
Perhexa 25B: trade name, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, decomposition temperature: 154°C, manufactured by NOF Corporation

<Antioxidant>
(1) Irganox 1076 (trade name, hindered phenol-based antioxidant, manufactured by BASF)
(2) Irganox MD1024 (trade name, hindered phenol-based antioxidant (metal deactivator), manufactured by BASF)

(Examples 1 to 11 and Comparative Examples 1 to 10)
Examples 1-11 and Comparative Examples 1-10 were carried out using the components shown in Tables 1 and 2, respectively.
In Tables 1 and 2, numerical values relating to compounding amounts (contents) in each example represent parts by mass unless otherwise specified. A blank column for each component means that the amount of the corresponding component is 0 parts by mass.
In each of the examples and comparative examples, part of the base resin (specifically, the polymer component shown in the "catalyst MB" column in Tables 1 and 2) was used as the carrier resin for the catalyst MB at the mass ratio shown in the same column. Using.

First, an inorganic filler, a silane coupling agent, and an organic peroxide are put into a rotary blade mixer (Mazeler PM: trade name, manufactured by Mazeler) at the mass ratio shown in the "Silane MB" column in Tables 1 and 2. Then, the mixture was stirred (pre-mixed) for 1 minute at room temperature (25° C.) at 10 rpm (step (a-1)). A powder mixture was thus obtained.
Next, the powder mixture and the polymer component (base resin) shown in the "Silane MB" column of Tables 1 and 2 are added to a kneader (capacity 75 L) heated to 100°C in advance at the mass ratio shown in the same column. After charging and mixing for 5 minutes at a rotation speed of 40 rpm, final kneading (melt mixing) was further performed at a rotation speed of 30 rpm for 3 minutes. After confirming that the resin temperature (temperature of the mixture) has reached 180 to 200° C., which is the decomposition temperature of the organic peroxide or higher, the molten mixture is pelletized using a feeder ruder and a pelletizer to obtain silane MB. obtained (step (a) together with step (a-2) and step (a-1)).

On the other hand, a polymer component (carrier resin), an antioxidant, and a silanol condensation catalyst were sequentially added to a kneader (capacity: 75 L) preliminarily heated to 80°C at the mass ratio shown in the "Catalyst MB" column of Tables 1 and 2. After charging and mixing for 5 minutes at a rotation speed of 30 rpm, finish kneading (melt mixing) was performed for 3 minutes at a rotation speed of 25 rpm. After confirming that the resin temperature (temperature of the mixture) reached about 160° C. and the carrier resin was sufficiently melted, pelletization was carried out using a feeder/ruder and a pelletizer to obtain a catalyst MB (step (b)). .

Next, the pellets of the silane MB and the pellets of the catalyst MB were dry-blended in a tumbler mixer at room temperature (25° C.) for 2 minutes immediately before extrusion to obtain a dry blend (dry blend in step (c)). blending process). At this time, the mixing ratio of the silane MB and the catalyst MB was the mass ratio shown in the "Silane MB" column and the "Catalyst MB" column in Tables 1 and 2.

Using each of the prepared dry blends, a tape-shaped molded article and a tubular molded article were produced as follows.
(1) Production of tape-shaped molded body (crosslinked body) L / D (ratio of screw effective length L to diameter D) = 25 mm (screw diameter) extruder, die head temperature 180 ° C., below, cylinder It was divided into three zones toward the feeder side of the part, and the extrusion temperature conditions were set to C3 = 180°C, C2 = 170°C, and C1 = 150°C. The dry blend obtained in the above step (c) is introduced into the extruder, and while melt-mixing at a screw rotation speed of 20 rpm (melt-mixing step of step (c)), a tape-shaped molded body having a thickness of 2 mm ( It was extruded (step (2)) into an uncrosslinked body). At this time, the silane crosslinkable resin composition is prepared by melt-mixing the dry blend in the extruder before extrusion molding.
The resulting tape-shaped molded article (uncrosslinked article) was allowed to stand in an atmosphere of 60° C. and 95% RH for 24 hours to bring the silane crosslinkable resin composition into contact with water (step (3)). .
In this manner, tape-shaped moldings (crosslinked bodies) formed from the silane crosslinked resin moldings were produced.

(2) Production of tape-shaped fusion-bonded body (crosslinked body) In the same manner as (1) Production of tape-shaped molded body (crosslinked body), a tape-shaped body (uncrosslinked body) having a thickness of 2 mm is extruded. (step (2)), and immediately after being extruded from the die outlet of the extruder, two tape-shaped moldings were collected without cooling. After that, the longitudinal ends of the tape-shaped moldings were overlapped by 10 mm and placed on a hot plate heated to 180°C. . In this state, it was heated at 180° C. for 30 seconds to obtain a tape-like fusion-bonded molded product (uncrosslinked product) in which the ends were fused together. This fusion between the ends assumes fusion in spiral molding.
After cooling the resulting tape-shaped fused molded product (uncrosslinked product) at room temperature (25°C) for 24 hours, the fused part is placed in the center of the reference point part, and the tape is adjusted according to JIS K 6251 (2017). A No. 3 dumbbell shape was punched out. Thereafter, the No. 3 dumbbell test piece was allowed to stand in an atmosphere of 60° C. temperature and 95% RH for 24 hours to bring the silane crosslinkable resin composition into contact with water (step (3)).
In this manner, tape-shaped fusion molded products (crosslinked products) formed from silane crosslinked resin molded products were produced.

The prepared silane MB, the produced tape-shaped molding (corresponding to a cross-linked product, silane-crosslinked resin molded product) or the tape-shaped fusion-bonded molded product (cross-linked product, corresponding to a silane-crosslinked resin molded product) were evaluated as follows. , and the results are shown in Tables 1 and 2.

<MFR measurement of silane MB>
The MFR of each silane MB prepared in Examples 1 to 11 and Comparative Examples 1 to 10 was measured according to JIS K 7210-1 (2014) under conditions of a temperature of 190° C. and a load of 2.16 kg.
When the MFR (190° C., 2.16 kg) of silane MB is 0.3 g/10 minutes or more, the silane crosslinkable resin composition prepared using this silane MB has excellent fluidity.
Since the silane crosslinked resin composition undergoes a silanol condensation reaction and the MFR cannot be measured under the above measurement conditions for MFR, this test is an alternative evaluation test for the fluidity of the silane crosslinked resin composition using silane MB.

<Appearance characteristics (extrusion appearance test)>
The appearance characteristic test of the tape-shaped molded body (crosslinked body) was visually conducted.
As a result, if the appearance (surface) is smooth and gel blisters could not be confirmed, "A" (good appearance, pass), and if significant flow marks, gel blisters, roughness, etc. can be confirmed on the surface, "D" ( Poor appearance, disqualified).

<Measurement of hardness (Shore A hardness)>
The Shore A hardness of each tape-shaped molding (crosslinked body) was measured according to JIS K 6253-3 (2012). Specifically, three tape-shaped moldings were superimposed to obtain a sample having a thickness of 6 mm.
The Shore A hardness is a test for evaluating the flexibility (hardness) of a silane crosslinked resin molded article. A Shore A hardness of 85 or less is considered flexible and excellent in bending resistance (accepted).

<Measurement of tensile strength>
Each tape-shaped molded body (crosslinked body) was punched into a No. 3 dumbbell-shaped test piece described in JIS K 6251 (2017). Using this test piece, the tensile strength (MPa) was measured according to JIS C 3005 under the conditions of a gauge line distance of 20 mm and a tensile speed of 200 mm/min.
The measurement of the tensile strength is a reference test assuming the scratch resistance of the wiring material (insulated wire), and a tensile strength of 6 MPa or more is passed.

<Hot set test>
A weight of 450 gf (44.1 N/cm ² ) was attached to the lower end of a No. 3 dumbbell test piece, which was a tape-shaped fusion-bonded molded product (crosslinked product), and hung vertically. It was left for 30 minutes under any temperature environment. This weight corresponds to the condition of attaching a weight of 10 kgf (38.8 cm ² ) to a hose (48 mm outer diameter, 38 mm inner diameter, 10 mm pitch, 2 mm thickness of tube wall made of silane crosslinked resin).
After 30 minutes (load removal), the gage length of the No. 3 dumbbell test piece was measured.
As a result, the part between the gauge marks (fused part) of the No. 3 dumbbell test piece did not peel off, and the gauge length of the No. 3 dumbbell test piece was 175 before the test (before applying load: initial gauge length). % (gauge length stretched by 2.75 times or less) is passed, and if the part between the gauge marks is peeled off or the gauge length exceeds 175% before the test, it is rejected. and In Tables 1 and 2, the measured gauge length (%) is indicated by a numerical value, and when the portion between the gauge marks is peeled off, it is indicated by "x".
In addition to the test for evaluating high-temperature characteristics, this test is a test assuming spiral molding applicability (spontaneous fusion), and the test must pass when left in a temperature environment of 100 ° C. for 30 minutes. Just do it. A test under a temperature environment of 105°C or higher is taken as a reference test, and it is preferable to pass a test under a higher temperature environment exceeding 100°C.

As is clear from the results in Tables 1 and 2, Comparative Examples 1 and 2, which do not contain polybutene resin and contain silane-crosslinkable polyethylene resin, regardless of the MFR of the containing polyethylene resin, the silane-crosslinkable resin composition The fluidity of the product is too low, and in the hot set test, the fused portion of the tape-shaped fusion-bonded product peels off, resulting in poor high-temperature properties. Comparative Examples 3 to 5, which do not contain a polybutene resin and contain a polypropylene resin that is difficult to be silane-crosslinked, exhibit good fluidity, but are inferior in either flexibility or appearance depending on the MFR of the contained polypropylene resin.
Further, in Comparative Example 6, which does not contain the ethylene-α-olefin copolymer rubber, the tape-shaped fusion-bonded molded product stretches too much (deforms too much) and is inferior in high-temperature properties. It is considered that this is because the silane crosslinked structure is not sufficiently constructed. On the other hand, Comparative Example 7, which contains an excessive amount of ethylene-α-olefin copolymer rubber, is excellent in high-temperature characteristics, but is inferior in appearance due to remarkable generation of gel lumps and the like. Furthermore, Comparative Example 8, in which the contents of the styrene-based elastomer and mineral oil are too low, is inferior in appearance and flexibility. This is considered to be due to the poor uniformity of the silane crosslinked structure.
In Comparative Example 9, which does not contain an inorganic filler, the tape-shaped fusion-bonded molded article is excessively stretched (deformed excessively) and is inferior in high-temperature properties. On the other hand, Comparative Example 10, which contains an excessive amount of inorganic filler, has too low fluidity and does not pass hardness and tensile strength.

On the other hand, Examples 1 to 11, which contain polybutene resin, ethylene-α olefin copolymer rubber, styrene elastomer, mineral oil, inorganic filler and silanol condensation catalyst in specific proportions, are all silane crosslinkable. The fluidity of the resin composition is high, and it is excellent in appearance, flexibility, and high-temperature properties.
Thus, the silane-crosslinkable resin composition of the present invention exhibits high fluidity when melted and is excellent in (extrusion) moldability. In addition, when a molded body (uncrosslinked body) of a silane crosslinkable resin composition is spiral-molded, both ends of the molded body can be rapidly fused, and the silane crosslinked resin molded body itself exhibits excellent flexibility. Therefore, it can be seen that the silane-crosslinkable resin composition of the present invention can produce silane-crosslinked resin molded articles that are flexible and excellent in bending resistance. This silane-crosslinked resin molded product is resistant to peeling of the fused portion, and can suppress the amount of deformation even if a large tension is applied in a high temperature environment of 100° C. without performing a special cross-linking treatment.

Claims (12)

100 parts by mass of a base resin containing 5 to 50% by mass of polybutene resin, 1 to 30% by mass of ethylene-α-olefin copolymer rubber, 5 to 40% by mass of styrene elastomer, and 5 to 40% by mass of mineral oil; A silane crosslinkable resin composition containing a silane coupling agent grafted to a resin, 0.5 to 50 parts by mass of an inorganic filler, and 0.01 to 0.5 parts by mass of a silanol condensation catalyst. The silane crosslinkable resin composition according to claim 1, wherein the base resin contains 12 to 40% by mass of the polybutene resin. 3. The silane crosslinkable resin composition according to claim 1, wherein the polybutene resin has a melt flow rate (190° C., 2.16 kg) of 0.3 to 2 g/10 minutes. The silane crosslinkable resin composition according to any one of claims 1 to 3, wherein the inorganic filler is at least one selected from metal hydrates, talc, clay, silica, calcium carbonate and carbon black. . The silane crosslinkable resin composition according to any one of claims 1 to 4, wherein the content of the silane coupling agent is 3 to 15 parts by mass with respect to 100 parts by mass of the base resin. A silane-crosslinked resin molded article obtained by molding the silane-crosslinkable resin composition according to any one of claims 1 to 5 and then contacting it with water. A silane crosslinked resin molded article comprising the silane crosslinked resin molded article according to claim 6 . The silane crosslinked resin molded article according to claim 7, which is a hose or tube. 9. The silane-crosslinked resin molded article according to claim 8, wherein the hose or tube is formed by contacting the spiral molded body of the silane-crosslinkable resin composition according to any one of claims 1 to 5 with water. With respect to 100 parts by mass of a base resin containing 5 to 50% by mass of polybutene resin, 1 to 30% by mass of ethylene-α-olefin copolymer rubber, 5 to 40% by mass of styrene elastomer, and 5 to 40% by mass of mineral oil, 0.5 to 50 parts by mass of an inorganic filler, 1 to 15 parts by mass of a silane coupling agent having a graft reaction site that can be grafted to the base resin, and 0.01 to 0.6 parts by mass of an organic peroxide. and 0.01 to 0.5 parts by mass of a silanol condensation catalyst are melt-mixed to obtain a silane crosslinkable resin composition (1).
The step (1) includes the following steps (a) and (c), provided that when a part of the base resin is melt-mixed in the following step (a), the following steps (a) and ( A method for producing a silane crosslinkable resin composition comprising b) and step (c).
Step (a): All or part of the base resin, the inorganic filler, and the silane cup
The ring agent and the organic peroxide are heated at a temperature equal to or higher than the decomposition temperature of the organic peroxide.
Step (b): Melt-mixing the remainder of the base resin and the silanol condensation catalyst to form a catalyst masterbatch.
Process for preparing a starbatch Step (c): the silane masterbatch and the silanol condensation catalyst or the catalyst master
-The process of melting and mixing the batch The step (1), the step (2) of obtaining a molded article by molding the silane crosslinkable resin composition, and the step (3) of contacting the molded article with water to obtain a silane crosslinked resin molded article. A method for producing a silane-crosslinked resin molded product. 12. The method for producing a silane-crosslinked resin molded article according to claim 11, wherein the step (2) of obtaining the molded article is a step of spiral-molding the silane-crosslinkable resin composition to obtain a tubular molded article.