JP6407339B2 - Heat-resistant silane cross-linked resin molded product and method for producing the same, heat-resistant silane cross-linked resin composition and method for producing the same, and heat-resistant product using heat-resistant silane cross-linked resin molded product - Google Patents

Description

The present invention, heat resistant silane crosslinked resin molded product and a manufacturing method thereof, heat silane crosslinkable resin composition and a production method thereof, and relates to a heat-resistant products using heat silane crosslinked resin molded product.
In particular, the present invention relates to a heat-resistant silane cross-linked resin molded article excellent in mechanical properties, flame retardancy and appearance, a method for producing the same, a heat-resistant silane cross-linkable resin composition capable of forming this heat-resistant silane cross-linked resin molded article, and a manufacturing method thereof, and relates to a heat-resistant products using heat silane crosslinked resin molded body as an insulator and sheath like the wire.

  Insulated wires, cables, cords and optical fiber cords used for electrical and electronic equipment internal and external wiring, optical fiber cords, flame resistance, heat resistance, mechanical properties (for example, tensile properties), wear resistance Various characteristics are required. As a material used for these wiring materials, a resin composition containing a large amount of an inorganic filler such as magnesium hydroxide, aluminum hydroxide, or calcium carbonate is used.

  In addition, wiring materials used in electrical and electronic equipment may be heated to 80 to 105 ° C. and further to about 125 ° C. when used for a long time, and heat resistance against this may be required. In such a case, for the purpose of imparting high heat resistance to the wiring material, a method of crosslinking the coating material by an electron beam crosslinking method, a chemical crosslinking method or the like is employed.

Conventionally, as a method of cross-linking polyolefin resins such as polyethylene, electron beam cross-linking by irradiating with an electron beam (also referred to as cross-linking), organic peroxide and the like are decomposed by applying heat after molding, and cross-linking reaction Known are chemical crosslinking methods, silane crosslinking methods, and the like.
The silane crosslinking method is a method in which a hydrolyzable silane coupling agent having an unsaturated group is grafted to a polymer in the presence of an organic peroxide to obtain a silane graft polymer, and then water and moisture in the presence of a silanol condensation catalyst. This is a method of obtaining a cross-linked molded article by contacting them.
Of these cross-linking methods, the silane cross-linking method in particular does not require special equipment and can be used in a wide range of fields.

  Specifically, a method for producing a halogen-free heat-resistant silane crosslinked resin is obtained by kneading a polyolefin resin and an inorganic filler, a silane masterbatch obtained by grafting a hydrolyzable silane coupling agent having an unsaturated group to a polyolefin resin. This is a method in which a heat-resistant master batch and a catalyst master batch containing a silanol condensation catalyst are melt-mixed. However, in this method, when the inorganic filler exceeds 100 parts by mass with respect to 100 parts by mass of the polyolefin resin, after the dry mixing of the silane masterbatch and the heat-resistant masterbatch, uniformly in a single screw extruder or a twin screw extruder It becomes difficult to melt and knead. For this reason, even if melt-kneading is uniformly performed after dry mixing of the silane masterbatch and the heat-resistant masterbatch, the proportion of the inorganic filler is limited. As a result, it was difficult to achieve higher flame resistance and higher heat resistance. Moreover, when manufactured using such a method, it is difficult to impart excellent strength, wear resistance, and reinforcing properties when a crosslinked resin is used.

Usually, when such inorganic filler exceeds 100 parts by mass with respect to 100 parts by mass of polyolefin resin, it is common to use a continuous mixer, a closed mixer such as a pressure kneader or a Banbury mixer. is there.
However, when silane grafting is carried out with a kneader or Banbury mixer, the hydrolyzable silane coupling agent having an unsaturated group is generally highly volatile and volatilizes before the graft reaction. Therefore, it was very difficult to produce a desired silane cross-linked master batch.

  Therefore, when producing a heat-resistant silane masterbatch using a Banbury mixer or kneader, a hydrolyzable silane coupling agent having an unsaturated group and an organic peroxidation are added to the heat-resistant masterbatch obtained by melting and mixing a polyolefin resin and an inorganic filler. A method may be considered in which a product is added and graft polymerization is carried out using a single screw extruder. However, in this method, the appearance of the molded product may be deteriorated due to variations in the reaction, or the amount of inorganic filler in the heat-resistant masterbatch must be increased very much, resulting in a significant increase in extrusion load. Became very difficult. As a result, a desired material or molded body could not be obtained. In addition, this is a two-step process, which is a difficult point in terms of manufacturing cost.

  In Patent Document 1, an inorganic filler, a silane coupling agent, an organic peroxide, and a cross-linking catalyst that are surface-treated with a silane coupling agent on a resin component obtained by mixing a polyolefin resin and a maleic anhydride resin in a kneader. A method of forming with a single screw extruder after sufficiently melt-kneading has been proposed.

  In addition, Patent Documents 2 to 4 describe a vinyl aromatic thermoplastic elastomer composition containing a block copolymer or the like as a base resin and a non-aromatic rubber softener added as a softener, and a silane surface-treated inorganic material. A method of partial crosslinking using an organic peroxide through a filler has been proposed.

JP 2001-101928 A JP 2000-143935 A JP 2000-315424 A JP 2001-240719 A

However, in the method described in Patent Document 1, the resin is partially crosslinked during melt kneading in a kneader, and the molded product may cause poor appearance (form a number of protrusions protruding on the surface). is there. Furthermore, most of the silane coupling agent other than the silane coupling agent whose surface is treated with an inorganic filler may be volatilized or condensed. As a result, desired heat resistance cannot be obtained, and condensation between silane coupling agents may cause deterioration of the appearance of the electric wire.
Moreover, even if it is the method described in patent documents 2-4, resin has not yet sufficient network structure. In addition, since the bond between the resin and the inorganic filler is released at a high temperature, it melts at a high temperature. For example, the insulation material melts during soldering of the electric wire, or the foam deformed when the molded body is secondarily processed. Sometimes occurred. Furthermore, when heated to about 200 ° C. for a short time, the appearance may be significantly deteriorated or deformed.

An object of the present invention is to provide a heat-resistant silane cross-linked resin molded article that suppresses volatilization of a hydrolyzable silane coupling agent and is excellent in mechanical properties, flame retardancy, and appearance, and a method for producing the same.
Moreover, this invention makes it a subject to provide the heat resistant silane crosslinkable resin composition which can form this heat resistant silane crosslinked resin molded object, and its manufacturing method.
Furthermore, this invention makes it a subject to provide the heat resistant product using the heat resistant silane crosslinked resin molded object obtained with the manufacturing method of the heat resistant silane crosslinked resin molded object.
Furthermore, this invention makes it a subject to provide the silane coupling agent mixing inorganic filler used suitably for the manufacturing method of a heat resistant silane crosslinked resin molding, and the manufacturing method of a heat resistant silane crosslinked resin composition.

  In the silane crosslinking method of the resin as described above, the present inventors have found that the surface area of the inorganic filler is important for improving the heat resistance, appearance, and mechanical properties of the heat-resistant silane crosslinked resin molded article, and further studies have been made. As a result, when an inorganic filler having a BET specific surface area set in a specific range is mixed with a specific amount of a hydrolyzable silane coupling agent in the method for producing a heat-resistant silane cross-linked resin molded article, the hydrolyzable silane coupling agent It has been found that a heat-resistant silane-crosslinked resin molded article that can suppress volatilization and that is excellent in both appearance and mechanical properties can be produced without impairing flame retardancy. The present inventors have further studied based on these findings, and have come to make the present invention.

That is, the subject of this invention was achieved by the following means.
<1> 100 parts by mass of resin (R), 0.01 to 0.6 parts by mass of organic peroxide (P), and 10 to 400 parts by mass of inorganic filler (B) having a BET specific surface area of 14 m ² / g or less. And hydrolyzable having a group capable of chemically bonding to the inorganic filler (B) and a group capable of grafting to the resin (R) in the presence of a radical with respect to 100 parts by mass of the inorganic filler (B). Silane coupling agent (S) 0.5-15.0 parts by mass and silanol condensation catalyst (C) are melt-mixed, and the group capable of undergoing graft reaction by radicals generated from the organic peroxide is used as the resin. A step (a) of obtaining a heat-resistant silane crosslinkable resin composition containing a silane crosslinkable resin by graft reaction with (R);
A step (b) of molding the heat-resistant silane crosslinkable resin composition;
A step (c) of obtaining a heat-resistant silane-crosslinked resin molded product by contacting the obtained molded product with water,
The step (a) includes the following step (1) and step (3). However, when a part of the resin (R) is melt-mixed in the following step (1), the following step (2) is further included. And
Step (1): All or part of the resin (R), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent (S) are combined with the organic peroxide. object(
A silane masterbatch containing a silane crosslinkable resin by melting and mixing at a decomposition temperature of P) or more and causing the resin (R) to graft-react the graftable group with radicals generated from the organic peroxide. Step (2): The step of preparing a catalyst master batch by melt-mixing the remainder of the resin (R) and the silanol condensation catalyst (C) Step (3): The silane master batch and the silanol Step of mixing the condensation catalyst (C) or the catalyst master batch to obtain a heat-resistant silane crosslinkable resin composition At least one of the inorganic fillers (B) is a fatty acid surface-treated inorganic filler.
A method for producing a heat-resistant silane-crosslinked resin molded product.
<2> In the step (1), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent at a temperature lower than the decomposition temperature of the organic peroxide (P). (S) is mixed, and then the obtained mixture and all or a part of the resin (R) are melt-mixed at a temperature equal to or higher than the decomposition temperature of the organic peroxide (P). For producing a functional silane cross-linked resin molded article.
<3> The method for producing a heat-resistant silane-crosslinked resin molded article according to <1> or <2>, wherein the inorganic filler (B) has a volume average diameter of 5 μm or less.
<4> The heat-resistant silane cross-linked resin molded article according to any one of <1> to <3>, wherein the resin (R) is mixed in both the steps (1) and (2). Manufacturing method.
<5> The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of <1> to <4>, wherein the fatty acid surface-treated inorganic filler is a fatty acid surface-treated metal hydrate.
<6> The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of <1> to <5>, wherein the fatty acid surface-treated inorganic filler is fatty acid surface-treated magnesium hydroxide.
<7> The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of <1> to < 4 >, wherein the fatty acid surface-treated inorganic filler is fatty acid surface-treated calcium carbonate.
<8> The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of <1> to <7>, wherein the step (1) is performed with a closed mixer.
<9> 100 parts by mass of resin (R), 0.01 to 0.6 parts by mass of organic peroxide (P), and 10 to 400 parts by mass of inorganic filler (B) having a BET specific surface area of 14 m ² / g or less. And hydrolyzable having a group capable of chemically bonding to the inorganic filler (B) and a group capable of grafting to the resin (R) in the presence of a radical with respect to 100 parts by mass of the inorganic filler (B). Silane coupling agent (S) 0.5-15.0 parts by mass and silanol condensation catalyst (C) are melt-mixed, and the group capable of undergoing graft reaction by radicals generated from the organic peroxide is used as the resin. (R) has a step (a) of obtaining a heat-resistant silane crosslinkable resin composition containing a silane crosslinkable resin by graft reaction;
The step (a) includes the following step (1) and step (3). However, when a part of the resin (R) is melt-mixed in the following step (1), the following step (2) is further included. And
Step (1): All or part of the resin (R), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent (S) are combined with the organic peroxide. object(
A silane masterbatch containing a silane crosslinkable resin by melting and mixing at a decomposition temperature of P) or more and causing the resin (R) to graft-react the graftable group with radicals generated from the organic peroxide. Step (2): The step of preparing a catalyst master batch by melt-mixing the remainder of the resin (R) and the silanol condensation catalyst (C) Step (3): The silane master batch and the silanol Step of mixing the condensation catalyst (C) or the catalyst master batch to obtain a heat-resistant silane crosslinkable resin composition At least one of the inorganic fillers (B) is a fatty acid surface-treated inorganic filler.
A method for producing a heat-resistant silane crosslinkable resin composition.

< 10 > A heat-resistant silane crosslinkable resin composition produced by the production method according to <9>.
< 11 > A heat-resistant silane-crosslinked resin molded product produced by the production method according to any one of <1> to <8>.
< 12 > A heat-resistant product comprising the heat-resistant silane-crosslinked resin molded product according to < 11 >.
< 13 > The heat-resistant product according to < 12 >, wherein the heat-resistant silane-crosslinked resin molded body is provided as a coating for an electric wire or an optical fiber cable.

  When the inorganic filler (B) and the hydrolyzable silane coupling agent (S) are mixed in the method for producing a heat-resistant silane crosslinked resin molded article of the present invention, the hydrolyzable silane coupling agent (S) suppresses volatilization. To some extent, it binds strongly or weakly to the inorganic filler (B). When the inorganic filler (B) has a BET specific surface area in the above range, a hydrolyzable silane coupling agent (S) that binds strongly to the inorganic filler (B) and a hydrolyzable silane that binds weakly. The coupling agent (S) is formed with a good balance.

In the method for producing a heat-resistant silane-crosslinked resin molded article of the present invention, it is strongly bonded to the inorganic filler (B) (the reason is considered to be formation of a chemical bond with a hydroxyl group or the like on the surface of the inorganic filler). The silane coupling agent is networked while the inorganic filler (B) is included together with the cross-linked sites of the resins (R) by the condensation reaction between these hydrolyzable silane coupling agents. Thereby, the heat-resistant silane crosslinked resin molding of the present invention can obtain very excellent mechanical properties.
On the other hand, a hydrolyzable silane cup that binds weakly to the inorganic filler (B) (for example, interaction by hydrogen bond, interaction between ions, partial charges or dipoles, action by adsorption, etc.) The ring agent is released from the inorganic filler (B), and the crosslinking group is grafted to the crosslinking site of the resin (R) by radicals generated by decomposition of the organic peroxide (P). Thereafter, the hydrolyzable group undergoes a condensation reaction. Thereby, resin (R) can be bridge | crosslinked. Therefore, the heat-resistant silane crosslinked resin molded product of the present invention can exhibit excellent heat resistance.

As described above, in the method for producing a heat-resistant silane crosslinked resin molded article of the present invention, the inorganic filler (B) having a BET specific surface area of 14 m ² / g or less is added to a specific amount of a hydrolyzable silane coupling agent in a specific step. When mixed, it is possible to suppress volatilization of the hydrolyzable silane coupling agent at the time of kneading, and furthermore, a heat-resistant silane crosslinked resin molded article excellent in both appearance and mechanical properties without impairing flame retardancy. Can be manufactured.

  Therefore, according to the present invention, the volatility of the hydrolyzable silane coupling agent is suppressed, and the heat-resistant silane cross-linked resin molded article excellent in mechanical properties, flame retardancy and appearance, its production method, and this heat-resistant silane cross-linked resin molded product A heat-resistant silane crosslinkable resin composition capable of forming a body and a method for producing the same can be provided. In addition, according to the present invention, a heat-resistant product using the heat-resistant silane cross-linked resin molded product obtained by the method for producing a heat-resistant silane cross-linked resin molded product can be provided. Furthermore, according to the present invention, it is possible to provide a silane coupling agent mixed inorganic filler that is suitably used in a method for producing a heat-resistant silane cross-linked resin molded product and a method for producing a heat-resistant silane cross-linkable resin composition.

  Below, this invention and preferable embodiment in this invention are demonstrated in detail.

In the “method for producing a heat-resistant silane-crosslinked resin molded article” of the present invention, 100 parts by mass of the resin (R), 0.01 to 0.6 parts by mass of the organic peroxide (P), and a BET specific surface area of 14 m ^{2 are used.} / G or less inorganic filler (B) 10-400 parts by mass, hydrolyzable silane coupling agent (S) 0.5-15.0 parts by mass with respect to 100 parts by mass of this inorganic filler (B), and silanol A step (a) of obtaining a mixture by melting and mixing the condensation catalyst (C), a step (b) of forming the mixture, and a step of obtaining a heat-resistant silane-crosslinked resin molded product by bringing the molded product into contact with water (c) ). And this process (a) consists of a process (1) and a process (3) at least, and when melt-mixing a part of resin (R) by a process (1), following process (1), process (2) ) And step (3).
Step (1): All or part of resin (R), organic peroxide (P), and inorganic filler (B)
And a hydrolyzable silane coupling agent (S) are melt-mixed at a temperature equal to or higher than the decomposition temperature of the organic peroxide (P) to prepare a silane masterbatch Step (2): Resin (R) remainder and silanol Step of preparing a catalyst master batch by melting and mixing the condensation catalyst (C) Step (3): Step of mixing the silane master batch and the silanol condensation catalyst (C) or catalyst master batch To obtain a uniform mixture.

  Moreover, the manufacturing method of the heat-resistant silane crosslinking resin composition used for the manufacturing method of the heat-resistant silane crosslinking resin molding of this invention has the above-mentioned process (a), and the above-mentioned process (b) and process ( c) is not an essential step.

  As described above, the “method for producing a heat-resistant silane cross-linked resin molded product” of the present invention and the “method for producing a heat-resistant silane cross-linkable resin composition” of the present invention are other than the presence or absence of the step (b) and the step (c). Is basically the same. Accordingly, the “method for producing a heat-resistant silane cross-linked resin molded product” of the present invention and the “method for producing a heat-resistant silane cross-linkable resin composition” of the present invention (in the explanation of the common parts of both, The manufacturing method of the present invention is sometimes described below.

  First, each component used in the present invention will be described.

<Resin (R)>
The resin (R) used in the production method of the present invention includes a crosslinking site that undergoes a crosslinking reaction in the presence of the crosslinking group of the hydrolyzable silane coupling agent (S) and the organic peroxide (P), such as a non-carbon chain. Any resin having a saturated bonding site or a carbon atom having a hydrogen atom in the main chain or at the terminal thereof may be used. For example, polyolefin resin (PO), polyester resin (PE), polyamide resin (PA), polystyrene resin (PS), polyol resin and the like can be mentioned. Among these, polyolefin resin (PO) is preferable. This resin (R) may be used individually by 1 type, and may use 2 or more types together.

  The polyolefin resin (PO) is not particularly limited as long as it is a resin obtained by polymerizing or copolymerizing a compound having an ethylenically unsaturated bond. Conventionally, a known polyolefin resin (PO) used in heat-resistant resin compositions is used. Things can be used. For example, polyethylene (PE), polypropylene (PP), ethylene-α-olefin copolymer, block copolymer of polypropylene and ethylene-α-olefin resin, polyolefin copolymer having an acid copolymerization component or an acid ester copolymerization component. Examples include polymers and resins made of these rubbers, elastomers, styrene elastomers, ethylene-propylene rubbers (for example, ethylene-propylene-diene rubbers), and the like. Among these, polyethylene (PE) and polypropylene (PP) are highly receptive to various fillers such as metal hydrates and can maintain mechanical strength even if a large amount of inorganic filler (B) is blended. ), A resin such as an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymerization component or an acid ester copolymerization component, a styrene-based elastomer, and an ethylene-propylene rubber. These polyolefin resins (PO) may be used alone or in combination of two or more.

  The polyethylene may be a resin containing an ethylene component as a main component, and is a homopolymer composed only of ethylene, a copolymer of ethylene and 5 mol% or less α-olefin (excluding propylene), and ethylene and a functional group. Includes a copolymer with 1 mol% or less non-olefin having only carbon, oxygen and hydrogen atoms (for example, JIS K 6748). In addition, the above-mentioned α-olefin and non-olefin can be used without particular limitation as well-known ones conventionally used as a copolymerization component of polyethylene.

  Examples of polyethylene that can be used in the present invention 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). Etc. Of these, linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) are preferable. Polyethylene may be used individually by 1 type, and may use 2 or more types together.

The polypropylene may be a resin having a propylene component as a main component, and includes a propylene homopolymer, an ethylene-propylene copolymer such as random polypropylene, and a block polypropylene as a copolymer.
Here, “random polypropylene” refers to a copolymer of propylene and ethylene having an ethylene component content of 1 to 5% by mass.
“Block polypropylene” is a composition containing homopolypropylene and an ethylene-propylene copolymer, and the ethylene component content is about 5 to 15% by mass or less, and the ethylene component and the propylene component exist as independent components. Say what you do.
Polypropylene may be used alone or in combination of two or more.

As the ethylene-α-olefin copolymer, a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms (excluding those contained in the above-described polyethylene and polypropylene) is preferable.
Specific examples of the α-olefin component in the ethylene-α-olefin copolymer include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene and the like. These components are mentioned. The ethylene-α-olefin copolymer is preferably a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms (excluding those contained in polyethylene and polypropylene). Examples include propylene copolymers (EPR, except those contained in polypropylene), ethylene-butylene copolymers (EBR), and ethylene-α-olefin copolymers synthesized in the presence of a single site catalyst. It is done. An ethylene-alpha-olefin copolymer may be used individually by 1 type, and may use 2 or more types together.

  As an acid copolymerization component or an acid ester copolymerization component in a polyolefin copolymer having an acid copolymerization component or an acid ester copolymerization component, each component such as vinyl acetate, (meth) acrylic acid, alkyl (meth) acrylate, etc. Is mentioned. Here, the alkyl group of the alkyl (meth) acrylate component preferably has 1 to 12 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, and a hexyl group. Examples of the polyolefin copolymer (excluding those contained in polyethylene) having an acid copolymerization component or an acid ester copolymerization component include, for example, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, Examples include ethylene- (meth) acrylic acid alkyl copolymers. Among these, an ethylene-vinyl acetate copolymer, an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, and an ethylene-butyl acrylate copolymer are preferable, and further, the acceptability of the inorganic filler (B). In view of heat resistance, ethylene-vinyl acetate copolymer and ethylene-ethyl acrylate copolymer are preferable. The polyolefin copolymer having an acid copolymerization component or an acid ester copolymerization component may be used alone or in combination of two or more.

Examples of the styrenic elastomer include block copolymers and random copolymers of conjugated diene compounds and aromatic vinyl compounds, or hydrogenated products thereof. Examples of the aromatic vinyl compound include styrene, p- (t-butyl) styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-aminoethyl. Styrene, vinyl toluene, p- (t-butyl) styrene, etc. are mentioned. Among these, styrene is preferable as the aromatic vinyl compound. This aromatic vinyl compound may be used individually by 1 type, and may use 2 or more types together. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like. Among these, the conjugated diene compound is preferably butadiene. This conjugated diene compound may be used individually by 1 type, and may use 2 or more types together. In addition, as a styrene-based elastomer, an elastomer containing an aromatic vinyl compound other than styrene, which does not contain a styrene component, may be used by a similar production method.
Specific examples of the styrene elastomer include, for example, Septon 4077, Septon 4055, Septon 8105 (all trade names, manufactured by Kuraray Co., Ltd.), Dynalon 1320P, Dynalon 4600P, 6200P, 8601P, 9901P (all trade names, JSR Corporation) Manufactured) and the like.

  Resin (R) can also be used with various oils used as a plasticizer or a softener if desired. In this case, the content of the resin (R) is preferably 20% by mass or more and more preferably 45% by mass or more with respect to the total mass of the resin (R) and oil in terms of heat resistance performance, crosslinking performance, and strength. Preferably, 60 mass% or more is more preferable. Although the content rate of resin (R) is 100 mass% at maximum, it can also be made into 80 mass% or less, for example.

The oil content is preferably 80% by mass or less, more preferably 55% by mass or less, and still more preferably 40% by mass or less with respect to the total mass of the resin (R) and the oil. The oil content is at least 0% by mass, but can be 20% by mass or more, for example.
In addition to the oil, the resin (R) may contain other components such as various additives, a solvent, an organic peroxide (P), and the like described later.

  Examples of the oil include oil as a plasticizer for resin (R) or a mineral oil softener for rubber. Such a mineral oil softening agent is a mixture of an aromatic ring, a naphthene ring and a paraffin chain in which the number of carbon atoms in the paraffin chain occupies 50% or more of the total carbon number. Those having a ring carbon number of 30-40% are called naphthenic oils, and those having 30% or more aromatic carbons are called aroma oils. Among these, liquid or low molecular weight synthetic softeners, paraffin oil, and naphthene oil are preferably used, and paraffin oil is particularly preferably used. Examples of such oils include Diana Process Oil PW90 and PW380 (both are trade names, manufactured by Idemitsu Kosan Co., Ltd.), Cosmo Neutral 500 (Cosmo Oil Co., Ltd.), and the like.

<Organic peroxide (P)>
The organic peroxide (P) generates radicals by thermal decomposition and serves to promote the grafting reaction of the hydrolyzable silane coupling agent (S) to the resin (R). In particular, when the hydrolyzable silane coupling agent (S) contains an ethylenically unsaturated group, grafting by a radical reaction between the ethylenically unsaturated group and the resin (R) (including a reaction of abstracting a hydrogen radical from the resin) It works to promote the reaction. The organic peroxide (P) is not particularly limited as long as it generates radicals. For example, the general formula: R ¹ —OO—R ² , R ¹ —OO—C (═O) R ³ , A compound represented by R ⁴ C (═O) —OO (C═O) R ⁵ is preferably used. Here, R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group, an aryl group, or an acyl group. Among these, in the present invention, it is preferable that R ¹ , R ² , R ³ , R ⁴ and R ⁵ are all alkyl groups, or any one is an alkyl group and the rest is an acyl group.

  Examples of such organic peroxides include dicumyl peroxide (DCP), di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, , 5-Dimethyl-2,5-di (tert-butylperoxy) hexyne-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3, 3,5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxy Benzoate, tert-butyl peroxyisopropyl carbonate, diace Peroxide, lauroyl peroxide, may be mentioned tert- butyl cumyl peroxide and the like. Among these, in terms of odor, colorability, and scorch stability, dicumyl peroxide (DCP), 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5- Dimethyl-2,5-di- (tert-butylperoxy) hexyne-3 is preferred.

The decomposition temperature of the organic peroxide (P) is preferably 80 to 195 ° C, particularly preferably 125 to 180 ° C.
In the present invention, the decomposition temperature of the organic peroxide (P) means that when the organic peroxide (P) having a single composition is heated, the organic peroxide (P) itself becomes two or more kinds of compounds at a certain temperature or temperature range. It means the temperature at which a decomposition reaction takes place. Specifically, it refers to the temperature at which heat absorption or heat generation starts when heated from room temperature in a nitrogen gas atmosphere at a rate of temperature increase of 5 ° C./min by thermal analysis such as DSC method.

<Inorganic filler (B)>
The inorganic filler (B) used in the step (a) of the production method of the present invention is an inorganic filler having a BET specific surface area (JIS Z 8830: 2013) of 14 m ² / g or less.
The inorganic filler (B) can be used alone or in combination of two or more. In addition, a mixture of at least one of the untreated inorganic filler and the surface-treated inorganic filler can also be used.

The inorganic filler (B) has a BET specific surface area of 14 m ² / g or less according to JIS Z 8830: 2013. When the BET specific surface area of the inorganic filler (B) exceeds 14 m ² / g, the ratio of the hydrolyzable silane coupling agent (S) that strongly binds to the inorganic filler (B) increases, Crosslinking hardly occurs and heat resistance may be inferior. The BET specific surface area is preferably 12 m ² / g or less in that the heat-resistant silane cross-linked resin molded product exhibits higher heat resistance.
Although the BET specific surface area of an inorganic filler (B) is not specifically limited, 1.0 m < ² > / g or more is preferable and 1.5 m < ² > / g or more is more preferable. When the BET specific surface area is 1.0 m ² / g or more, the ratio of the hydrolyzable silane coupling agent (S) that strongly binds to the inorganic filler (B) increases, and the network includes the inorganic filler (B). Is formed, and mechanical properties are improved. Moreover, even if the state in which the inorganic filler (B) and the hydrolyzable silane coupling agent (S) are mixed for a long period of time, the hydrolyzable silane coupling agent (S) hardly aggregates due to silanol condensation, It becomes difficult to volatilize. Thereby, the heat resistance of a heat-resistant silane crosslinked resin molded object and the fall of an external appearance can be prevented.

  The BET specific surface area of the inorganic filler (B) is a value measured using nitrogen gas as an adsorbate in accordance with “Carrier Gas Method” of JIS Z 8830: 2013. For example, it can be measured using a specific surface area / pore distribution measuring apparatus “Flowsorb” (manufactured by Shimadzu Corporation).

The inorganic filler (B) preferably has a volume average diameter (MV) of 5 μm or less, more preferably 0.05 to 0.45 μm. When the volume average diameter (MV) of the inorganic filler (B) is 5 μm or less, the heat resistant silane crosslinked resin formed by bonding the inorganic filler (B) and the resin (R) via the silane coupling agent (S). The tensile strength of the molded body increases.
The volume average diameter (MV) of the inorganic filler (B) is obtained by dispersing the inorganic filler (B) in alcohol or water, and using, for example, a laser diffraction scattering type particle size measuring instrument “Microtrack” (manufactured by Nikkiso Co., Ltd.) It is a value measured by laser diffraction scattering type particle size distribution measurement.

Such an inorganic filler (B) should just have the above-mentioned BET specific surface area of 14 m < ² > / g or less, and is surface-treated with surface treatment agents, such as an untreated inorganic filler which is not surface-treated, a silane coupling agent, or a fatty acid. Surface treated inorganic fillers and the like.

  As an untreated inorganic filler, as long as the surface of the inorganic filler has a site capable of forming a hydrogen bond or the like with a reactive site such as a silanol group of a hydrolyzable silane coupling agent or a site capable of chemical bonding by a covalent bond It can be used without particular limitation. In this inorganic filler, the sites capable of chemically bonding with the reaction site of the hydrolyzable silane coupling agent include OH groups (hydroxy groups, water molecules containing water or crystal water, OH groups such as carboxyl groups), amino groups, and SH groups. Etc.

  Such an untreated inorganic filler is not particularly limited. For example, aluminum hydroxide, magnesium hydroxide, aluminum oxide, aluminum nitride, aluminum borate, hydrated magnesium silicate, calcium carbonate, magnesium carbonate, Metal hydroxide or metal water such as calcium silicate, magnesium silicate, calcium oxide, aluminum oxide, alumina, hydrated magnesium silicate, basic magnesium carbonate, hydrotalcite and other metal compounds having a hydroxyl group or crystal water Japanese, further boron nitride, silica (crystalline silica, amorphous silica, etc.), carbon, clay, zinc oxide, tin oxide, titanium oxide, molybdenum oxide, antimony trioxide, silicone compound, quartz, talc, Zinc borate, white carbon, Zinc hydroxy stannate, zinc stannate and the like can be used.

  A surface treatment inorganic filler is an inorganic filler surface-treated with a surface treatment agent such as a silane coupling agent or a fatty acid. The surface treatment agent is not particularly limited, and examples thereof include silane coupling agents, fatty acids such as stearic acid, oleic acid, and lauric acid, phosphate esters, polyesters, titanate coupling agents, and the like. Examples of the silane coupling agent include a hydrolyzable silane coupling agent described later. Although a fatty acid is not specifically limited, C10-22 saturated fatty acid and C10-22 unsaturated fatty acid are mentioned. Specifically, examples of the saturated fatty acid include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, alginic acid, and behenic acid. Examples of the unsaturated fatty acid include oleic acid, linolenic acid, and linoleic acid. The surface treatment amount can be appropriately determined depending on the type of surface treatment agent and the desired strength.

  The inorganic filler (B) is preferably a metal hydrate (metal hydroxide or the like), calcium carbonate, silica or a surface-treated product thereof, and more preferably magnesium hydroxide, aluminum hydroxide, calcium carbonate or a surface-treated product thereof.

<Hydrolyzable silane coupling agent (S)>
The hydrolyzable silane coupling agent only needs to have a group capable of grafting to the resin (R) in the presence of a radical and a group capable of chemically bonding to the inorganic filler (B). Those having an amino group, a glycidyl group or a group containing an ethylenically unsaturated group and hydrolyzable at the end are preferred, and more preferably a group containing an ethylenically unsaturated group and hydrolyzable at the end A hydrolyzable silane coupling agent having Although it does not specifically limit as group containing an ethylenically unsaturated group, For example, a vinyl group, an allyl group, a (meth) acryloyloxy group, a (meth) acryloyloxyalkylene group, p-styryl group etc. are mentioned. Moreover, you may use together these hydrolysable silane coupling agents and the hydrolysable silane coupling agent which has another terminal group.

  As such a hydrolyzable silane coupling agent, for example, a compound represented by the following general formula (1) can be used.

In general formula (I), R _a11 is a group containing an ethylenically unsaturated group, R _b11 is an aliphatic hydrocarbon group, a hydrogen atom, or Y ¹³ . Y ¹¹ , Y ¹² and Y ¹³ are hydrolyzable organic groups. Y ¹¹ , Y ¹² and Y ¹³ may be the same as or different from each other.

R _a11 of the hydrolyzable silane coupling agent represented by the general formula (1) is preferably a group containing an ethylenically unsaturated group, and the group containing an ethylenically unsaturated group is as described above. A vinyl group is preferred.

R _b11 is an aliphatic hydrocarbon group, a hydrogen atom, or Y ¹³ to be described later. The aliphatic hydrocarbon group is a monovalent aliphatic hydrocarbon group having 1 to 8 carbon atoms excluding the aliphatic unsaturated hydrocarbon group. and the like, preferably below ^{Y 13.}

Y ¹¹ , Y ¹² and Y ¹³ are hydrolyzable organic groups such as an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, and an acyloxy group having 1 to 4 carbon atoms. And an alkoxy group is preferred. Examples of the hydrolyzable organic group include methoxy, ethoxy, butoxy, acyloxy and the like. Among these, methoxy or ethoxy is more preferable, and methoxy is particularly preferable from the viewpoint of the reactivity of the hydrolyzable silane coupling agent.

The hydrolyzable silane coupling agent is preferably a hydrolyzable silane coupling agent having a high hydrolysis rate, more preferably R _b11 is Y ¹³ , and Y ¹¹ , Y ¹² and Y ¹³ are the same as each other. A hydrolyzable silane coupling agent, more preferably a hydrolyzable silane coupling agent in which at least one of Y ¹¹ , Y ¹² and Y ¹³ is a methoxy group, and particularly preferably all are methoxy groups It is a hydrolyzable silane coupling agent.

Specific examples of hydrolyzable silane coupling agents having a vinyl group, (meth) acryloyloxy group, or (meth) acryloyloxyalkylene group at the terminal include vinyltrimethoxysilane, vinyltriethoxysilane, and vinyltributoxysilane. , Vinyldimethoxyethoxysilane, vinyldimethoxybutoxysilane, vinyldiethoxybutoxysilane, allyltrimethoxysilane, allyltriethoxysilane, vinyltriacetoxysilane and other organosilanes, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, And methacryloxypropylmethyldimethoxysilane. These hydrolyzable silane coupling agents may be used alone or in combination of two or more. Among such crosslinkable hydrolyzable silane coupling agents, hydrolyzable silane coupling agents having a vinyl group and an alkoxy group at the terminal are more preferable, and vinyltrimethoxysilane and vinyltriethoxysilane are particularly preferable.
Those having a glycidyl group at the terminal are 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like.

<Silane coupling agent mixed inorganic filler (SF)>
The silane coupling agent mixed inorganic filler (SF) of the present invention is composed of 100 parts by mass of the inorganic filler (B) having a BET specific surface area of 14 m ² / g or less, and the above-described silane coupling agent (S) 0. The inorganic filler (B) is surface-treated with a hydrolyzable silane coupling agent (S).
When the present inventors mixed an inorganic filler (B) having a BET specific surface area in the above-mentioned range and a silane coupling agent (S) at a specific ratio, the hydrolyzable silane strongly bound to the inorganic filler (B). The ratio between the coupling agent and the hydrolyzable silane coupling agent that binds weakly is improved, and the heat-resistant silane cross-linked resin molded product that is the object of the present invention is effectively produced even after a long period of time has elapsed after mixing. I found out that I can do it.

Therefore, as will be described later, this silane coupling agent mixed inorganic filler (SF) has high stability and can maintain its performance even after long-term storage. This silane coupling agent mixed inorganic filler (SF) is suitably used in a silane crosslinking method including condensation of silanols, and can be used in addition to the silane crosslinking method by utilizing its stability and reactivity. .
This silane coupling agent mixed inorganic filler (SF) is prepared, for example, in step (1) of the production method of the present invention. A method for mixing the inorganic filler (B) and the hydrolyzable silane coupling agent (S) will be described later.

<Silanol condensation catalyst (C)>
The silanol condensation catalyst (C) functions to cause the hydrolyzable silane coupling agent (S) grafted to the resin (R) to undergo a condensation reaction in the presence of moisture. Based on the action of the silanol condensation catalyst (C), when the resins (R) are cross-linked via the hydrolyzable silane coupling agent (S), a heat-resistant silane cross-linked resin molded article having excellent heat resistance is obtained. can get.

  As the silanol condensation catalyst (C), an organic tin compound, a metal soap, a platinum compound, or the like is used. Common silanol condensation catalysts (C) include, for example, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctate, dibutyltin diacetate, zinc stearate, lead stearate, barium stearate, calcium stearate, stearin Sodium acid, lead naphthenate, lead sulfate, zinc sulfate, organic platinum compounds and the like are used. Among these, organic tin compounds such as dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctiate, and dibutyltin diacetate are particularly preferable.

  The silanol condensation catalyst (C) is mixed with the resin as desired. Such a resin (also referred to as carrier resin) is not particularly limited, and examples thereof include the same resin as the resin (R). The carrier resin is preferably a polyolefin resin in that it has an affinity with the silanol condensation catalyst (C) and is excellent in heat resistance, and a resin made of polyethylene (PE) is particularly preferable.

<Additives>
The heat-resistant silane cross-linked resin molded body and the heat-resistant silane cross-linkable resin composition are various additives commonly used in electric wires, electric cables, electric cords, sheets, foams, tubes, pipes, for example, A crosslinking aid, an antioxidant, a lubricant, a metal deactivator, a filler, other resins and the like may be appropriately blended within a range not impairing the object of the present invention. These additives, particularly antioxidants and metal deactivators, may be contained in any component, but are preferably added to the carrier resin. It is preferable that the crosslinking aid is not substantially contained. In particular, it is preferable that the crosslinking aid is not substantially mixed in the step (1) of preparing the silane master batch. If the crosslinking aid is not substantially mixed, crosslinking between the resins (R) hardly occurs during kneading, and the heat resistant silane crosslinked resin molded article is excellent in appearance and heat resistance. Here, being substantially not contained or not mixed means that a crosslinking aid is not actively added or mixed, and does not exclude inclusion or mixing unavoidably.

  The crosslinking aid refers to a compound that forms a partially crosslinked structure with the resin (R) in the presence of an organic peroxide. For example, a methacrylate compound such as polypropylene glycol diacrylate and trimethylolpropane triacrylate, triallyl cyanide, and the like. Examples include allyl compounds such as nurate, polyfunctional compounds such as maleimide compounds and divinyl compounds.

  Antioxidants such as 4,4′-dioctyldiphenylamine, N, N′-diphenyl-p-phenylenediamine, 2,2,4-trimethyl-1,2-dihydroquinoline polymer, etc. Agents, pentaerythrityl-tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene and the like, bis (2-methyl-4- (3 -N-alkylthiopropionyloxy) -5-tert-butylphenyl) sulfide, 2-mercaptoben ヅ imidazole and Zinc salts, pentaerythritol - tetrakis (3-lauryl - thiopropionate) sulfur antioxidant such as and the like. The antioxidant can be added in an amount of preferably 0.1 to 15.0 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin (R).

  Examples of the lubricant include hydrocarbons, siloxanes, fatty acids, fatty acid amides, esters, alcohols, metal soaps, and the like. These lubricants should be added to the carrier resin (E).

  Examples of metal deactivators include N, N′-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3- (N-salicyloyl) amino-1,2,4. -Triazole, 2,2'-oxamidobis- (ethyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) and the like.

  Examples of the filler (including a flame retardant (auxiliary) agent) include fillers other than the various fillers described above.

Next, the production method of the present invention will be specifically described.
In the production method of the present invention, the step (a) includes 100 parts by mass of the resin (R), 0.01 to 0.6 parts by mass of the organic peroxide (P), and a BET specific surface area of 14 m ² / g or less. 10 to 400 parts by mass of the inorganic filler (B), 0.5 to 15.0 parts by mass of a hydrolyzable silane coupling agent (S) with respect to 100 parts by mass of the inorganic filler (B), and a silanol condensation catalyst (C ) Is melt-mixed to obtain a mixture.

  The mixing amount of the organic peroxide (P) is 0.01 to 0.6 parts by mass and preferably 0.1 to 0.5 parts by mass with respect to 100 parts by mass of the resin (R). When the mixing amount of the organic peroxide (P) is less than 0.01 parts by mass, the crosslinking reaction does not proceed at the time of crosslinking, the crosslinking reaction does not proceed at all, or the free hydrolyzable silane coupling agents (S) are In some cases, the heat resistance, mechanical strength, wear resistance, and reinforcement cannot be sufficiently obtained due to bonding. On the other hand, when it exceeds 0.6 parts by mass, the hydrolyzable silane coupling agent (S) is likely to volatilize, and the resin (R) may be directly cross-linked by a side reaction, and there is a risk that it will be crushed. is there.

  The mixing amount of the inorganic filler (B) is 10 to 400 parts by mass, preferably 30 to 280 parts by mass with respect to 100 parts by mass of the resin (R). When the mixing amount of the inorganic filler (B) is less than 10 parts by mass, the graft reaction of the hydrolyzable silane coupling agent (S) becomes non-uniform, and the desired heat resistance cannot be obtained, or the non-uniform reaction There is a risk that the appearance may deteriorate. On the other hand, if it exceeds 400 parts by mass, the load during molding or kneading becomes very large, and secondary molding may be difficult.

  The mixing amount of the hydrolyzable silane coupling agent (S) is 0.5 to 15.0 parts by mass, preferably 1.0 to 14.0 parts by mass with respect to 100 parts by mass of the inorganic filler (B). 2.0-13.0 parts by mass are more preferable. When the mixing amount of the hydrolyzable silane coupling agent (S) is less than 0.5 parts by mass, the crosslinking reaction does not proceed sufficiently and the excellent flame resistance may not be exhibited. On the other hand, when the amount exceeds 15 parts by mass, the hydrolyzable silane coupling agents (S) are condensed with each other to cause brittleness or burn of the crosslinked gel, which may deteriorate the appearance. In some cases, molding is not possible.

  In the production method of the present invention, in the step (a), the resin (R) includes “a total amount of the resin (R), that is, an aspect in which 100 parts by mass” is blended, and “a part of the resin (R) is blended. Embodiment ". Therefore, in the production method of the present invention, it is sufficient that 100 parts by mass of the resin (R) is contained in the mixture obtained in the step (a), and the total amount of the resin (R) is the step (1) described later. A part thereof may be mixed as a carrier resin in the step (2) described later, that is, the resin (R) may be mixed in both the step (1) and the step (2). In addition, when mix | blending a part of resin (R) at a process (2), the mixing amount 100 mass part of resin (R) in a process (a) is mixed by the process (1) and a process (2). This is the total amount of the resin (R). Here, when the resin (R) is blended in the step (2), the resin (R) is preferably 80 to 99 parts by mass, more preferably 94 to 98 parts by mass in the step (1). In (2), preferably 1 to 20 parts by mass, more preferably 2 to 6 parts by mass are mixed.

This process (a) has a process (1) and a process (3), and further has a process (2) in a specific case. When the step (a) includes these steps, each component can be uniformly melted and mixed, and the desired effect can be obtained.
Step (1): All or part of resin (R), organic peroxide (P), and inorganic filler (B)
And a hydrolyzable silane coupling agent (S) are melt-mixed at a temperature equal to or higher than the decomposition temperature of the organic peroxide (P) to prepare a silane masterbatch Step (2): Resin (R) remainder and silanol condensation Step of preparing catalyst master batch by melting and mixing catalyst (C) Step (3): Step of mixing silane master batch and silanol condensation catalyst (C) or catalyst master batch

  In step (1), the resin (R), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent (S) are charged into the mixer, and the organic peroxide (P) A silane masterbatch is prepared by melting and kneading while heating at a temperature equal to or higher than the decomposition temperature.

  In the step (1), the kneading temperature for melting and mixing the above components is not less than the decomposition temperature of the organic peroxide (P), preferably the decomposition temperature of the organic peroxide (P) + (25 to 110) ° C. . This decomposition temperature is preferably set after the resin (R) is melted. Also, kneading conditions such as kneading time can be set as appropriate. When kneaded below the decomposition temperature of the organic peroxide (P), the silane coupling agent silane graft reaction, the bond between the silane coupling agent mixed inorganic filler and the resin (R), the silane coupling agent mixed inorganic filler Bonding does not occur and the desired heat resistance cannot be obtained. In addition, the organic peroxide (P) may react during extrusion, and may not be molded into a desired shape.

As a kneading method, any method usually used for rubber, plastics and the like can be used satisfactorily, and the kneading apparatus is appropriately selected according to, for example, the amount of the inorganic filler (B) mixed. As a kneading apparatus, a single screw extruder, a twin screw extruder, a roll, a Banbury mixer or various kneaders are used, and a closed mixer such as a Banbury mixer or various kneaders is used to disperse the resin (R) and stabilize the crosslinking reaction. From the viewpoint of sex.
In general, when such an inorganic filler (B) is mixed in excess of 100 parts by mass with respect to 100 parts by mass of the resin (R), kneading with a continuous kneader, a pressure kneader, or a Banbury mixer is generally used. Is.

  In the step (1), the mixing method is not particularly limited. For example, the above components can be melted and mixed at a time. Preferably, using a mixer-type kneader such as a Banbury mixer or a kneader, the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling at a temperature lower than the decomposition temperature of the organic peroxide (P). After mixing and dispersing the agent (S) in a mixer, the mixture and the resin (R) are melt-mixed. If it does in this way, the excessive crosslinking reaction of resin (R) can be prevented, and it is excellent in an external appearance. More preferably, the inorganic filler (B) and the hydrolyzable silane coupling agent (S) can be used at a temperature not higher than the decomposition temperature of the organic peroxide (P) in that it is possible to prevent the occurrence of defects due to local crosslinking reaction. Next, after mixing this mixture with the organic peroxide (P), the resin (R) is melt-mixed at a temperature equal to or higher than the decomposition temperature of the organic peroxide (P). By this mixing method, a silane coupling agent mixed inorganic filler (SF) is prepared in advance.

  Inorganic filler (B), hydrolyzable silane coupling agent (S) and optionally organic peroxide (P) are mixed below the decomposition temperature of organic peroxide (P), preferably at room temperature (25 ° C.). Preferably it is done. Examples of the mixing of the inorganic filler (B), the hydrolyzable silane coupling agent (S), and, if desired, the organic peroxide (P) include mixing methods such as wet processing and dry processing.

As a method of mixing the inorganic filler (B) and the hydrolyzable silane coupling agent (S), a wet treatment in which the hydrolyzable silane coupling agent (S) and the inorganic filler (B) are mixed in alcohol or water, Examples thereof include a dry treatment for blending the inorganic filler (B) and the hydrolyzable silane coupling agent (S), and both.
In the wet treatment, for example, the inorganic filler (B) is uniformly dispersed in a solvent such as water, the hydrolyzable silane coupling agent (S) is added thereto, and after sufficient mixing, the slurry mixture is dried. . In the dry treatment, for example, the inorganic filler (B) is put into, for example, a ribbon blender, and the hydrolyzable silane coupling agent (S) is added thereto and stirred. Conditions in these wet processing and dry processing are not particularly limited and are appropriately selected. In this manner, when the inorganic filler (B) and the hydrolyzable silane coupling agent (S) are mixed, the inorganic filler (B) formed by strong bonding with the hydrolyzable silane coupling agent (S), A silane coupling agent mixed inorganic filler (SF) containing a decomposable silane coupling agent (S) and an inorganic filler (B) that is weakly bonded is obtained.

  In the silane coupling agent mixed inorganic filler (SF) of the present invention, a hydrolyzable silane coupling agent that strongly binds to the inorganic filler (B) and a hydrolyzable silane coupling agent that weakly bonds to the inorganic filler (B) As described later, it shows different behavior. Therefore, the effect obtained by the ratio of these hydrolyzable silane coupling agents is different. For example, when the silane coupling agent-mixed inorganic filler (SF) of the present invention is used as a filler for the silane crosslinking method, the hydrolyzable silane coupling agent that binds weakly to the inorganic filler (B) is between the resins (R). The hydrolyzable silane coupling agent that contributes to crosslinking and strongly binds to the inorganic filler (B) includes condensation of hydrolyzable silane coupling agents, and the silane coupling agent mixed inorganic filler (SF) and resin (R) It contributes to the combination with.

Thus, in the silane coupling agent mixed inorganic filler (SF) of the present invention, when the BET specific surface area of the inorganic filler is 14 m ² / g or less, the hydrolyzable silane coupling that strongly binds to the inorganic filler (B). The ratio of the agent (S) becomes appropriate, and it is excellent in all of heat resistance, appearance, and mechanical properties without impairing flame retardancy. In addition, silanol condensation and volatilization of the hydrolyzable silane coupling agent (S) that binds weakly to the inorganic filler (B) can be prevented, and even if the silane coupling agent mixed inorganic filler (SF) of the present invention is stored for a long period of time, A heat-resistant silane cross-linked resin molded article having excellent flame retardancy, appearance, and mechanical properties can be produced.

  Thus, a silane masterbatch is prepared by implementing a process (1).

The silane masterbatch prepared in the step (1) is a reaction mixture of a decomposition product of an organic peroxide (P), a resin (R), an inorganic filler (B), and a hydrolyzable silane coupling agent (S). Yes, the hydrolyzable silane coupling agent contains a silane crosslinkable resin grafted on the resin (R) to the extent that it can be molded by the step (b) described later.
This silane masterbatch contains a silane crosslinkable resin obtained by grafting the hydrolyzable silane coupling agent (S) to the resin (R).

  Next, in the production method of the present invention, when part of the resin (R) is melt-mixed in the step (1), the remainder of the resin (R) and the silanol condensation catalyst (C) are melt-mixed to obtain a catalyst. Step (2) of preparing a master batch is performed. Therefore, when all the resin (R) is melt-mixed in the step (1), the step (2) may not be performed, and other resins described later may be used.

  The mixing amount of the silanol condensation catalyst (C) is preferably 0.0001 to 0.5 parts by mass, more preferably 0.001 to 0.00 parts per 100 parts by mass of the resin (R) to be mixed in the step (a). 1 part by mass. When the mixing amount of the silanol condensation catalyst (C) is within the above-mentioned range, the crosslinking reaction by the condensation reaction of the hydrolyzable silane coupling agent (S) is likely to proceed almost uniformly, and the heat resistance of the heat-resistant silane crosslinked resin molded product. Excellent in properties, appearance and physical properties, and productivity is improved.

  The resin (R) is mixed with the silanol condensation catalyst (C) as a carrier resin, and preferably the remainder of the resin (R) mixed in the step (1) is used. The remainder (mixing amount) of the resin (R) is as described above.

The silanol condensation catalyst (C) may be mixed with another carrier resin instead of or in addition to the remainder of the resin (R). That is, in the step (2), the remainder of the resin (R) when a part of the resin (R) is melt-mixed in the step (1), or a resin other than the resin (R) used in the step (1) Then, the silanol condensation catalyst (C) is melt-mixed to prepare a catalyst master batch. The resin other than the resin (R), that is, other carrier resin is not particularly limited, and various resins can be used.
When the carrier resin is a resin other than the resin (R), 100 parts by mass of the resin (R) can be used because the silane crosslinking can be accelerated quickly in the step (b), and gelling is less likely to occur during molding. The amount is preferably 1 to 60 parts by mass, more preferably 2 to 50 parts by mass, and still more preferably 2 to 40 parts by mass.

  In addition, a filler may or may not be added to this carrier resin. The amount of the filler at that time is not particularly limited, but is preferably 350 parts by mass or less with respect to 100 parts by mass of the carrier resin. This is because if the amount of filler is too large, the silanol condensation catalyst is difficult to disperse and crosslinking is difficult to proceed. On the other hand, if the carrier resin is too much, the degree of cross-linking of the molded article is lowered, and there is a possibility that proper heat resistance cannot be obtained.

  The catalyst masterbatch prepared in step (2) is a mixture of a silanol condensation catalyst (C), a carrier resin, and a filler that is optionally added.

Next, in the production method of the present invention, the step (3) of obtaining a mixture by mixing the silane masterbatch with the silanol condensation catalyst (C) or the catalyst masterbatch prepared in the step (2) is performed.
Any mixing method may be used as long as a uniform mixture can be obtained. For example, pellets such as dry blends may be mixed and introduced into a molding machine at room temperature or high temperature, or may be mixed and melted and pelletized again and then introduced into the molding machine.
In any mixing, in order to avoid the silanol condensation reaction, it is preferable that the silane master batch and the silanol condensation catalyst (C) or the catalyst master batch are not maintained at a high temperature for a long time. About the obtained mixture, it is set as the mixture with which the moldability in the shaping | molding in a process (b) was hold | maintained.

  When the silanol condensation catalyst (C) is mixed alone with the silane master batch, the mixing conditions are set to appropriate melt mixing conditions according to the resin (R).

  When the catalyst master batch containing the silanol condensation catalyst (C) is mixed with the silane master batch, melt mixing is preferable in terms of dispersion of the silanol condensation catalyst (C), which is basically the same as the melt mixing in the step (1). is there. There are resins (R) whose melting point cannot be measured by DSC or the like, for example, elastomers, but they are kneaded at a temperature at which the resin (R) melts. The melting temperature is appropriately selected according to the melting temperature of the resin (R), and is preferably 80 to 250 ° C., more preferably 100 to 240 ° C., for example. The kneading conditions such as kneading time can be set as appropriate.

  This step (3) may be a step in which a silane master batch and a silanol condensation catalyst (C) are mixed to obtain a mixture, and a catalyst master batch and a silane master batch containing the silanol condensation catalyst (C) and a carrier resin. It is preferable to be a step of melt-mixing.

  Thus, the process (a) of the present invention, that is, the method for producing the heat-resistant silane crosslinkable resin composition of the present invention is carried out, and the heat-resistant silane containing silane crosslinkable resins different in at least two kinds of crosslinking methods A crosslinkable resin composition is produced. Therefore, the heat-resistant silane crosslinkable resin composition of the present invention is a composition obtained by carrying out step (a), and is a mixture of a silane masterbatch and a silanol condensation catalyst (C) or a catalyst masterbatch. Conceivable. The components are basically the same as the silane masterbatch and silanol condensation catalyst (C) or catalyst masterbatch.

  Next, the manufacturing method of the heat-resistant silane crosslinked resin molding of this invention performs a process (b) and a process (c). That is, in the method for producing a heat-resistant silane cross-linked resin molded product of the present invention, the step (b) of obtaining the molded product by molding the obtained mixture, that is, the heat-resistant silane cross-linked resin composition of the present invention is performed. This process (b) should just be able to shape | mold a mixture, and according to the form of the heat resistant product of this invention, a shaping | molding method and shaping | molding conditions are selected suitably. For example, when the heat-resistant product of the present invention is an electric wire or an optical fiber cable, extrusion molding or the like is selected.

  Step (b) can be carried out simultaneously or sequentially with step (3) of step (a). For example, a series of steps in which a silane masterbatch and a silanol condensation catalyst (C) or a catalyst masterbatch are melt-kneaded in a coating apparatus and then coated on, for example, an extruded electric wire or fiber and formed into a desired shape can be employed.

  Thus, the heat-resistant silane crosslinkable resin composition of the present invention is molded, and the molded body of the heat-resistant silane crosslinkable resin composition obtained in the steps (a) and (b) is an uncrosslinked body. Therefore, the heat-resistant silane crosslinked resin molded product of the present invention is a molded product that is crosslinked or finally crosslinked by performing the following step (c) after the step (a) and the step (b).

  In the method for producing a heat-resistant silane crosslinked resin molded article of the present invention, the hydrolyzable group of the hydrolyzable silane coupling agent is obtained by bringing the molded article (uncrosslinked article) obtained in step (b) into contact with water. Is hydrolyzed to form silanol, and the silanol condensation catalyst (C) present in the resin condenses the hydroxyl groups of silanol to cause a crosslinking reaction. Thereby, the process (c) which obtains the heat resistant silane crosslinked resin molded object which consists of a crosslinked molded object is implemented. The process itself of this process (c) can be performed by a normal method. By bringing moisture into contact with the molded product, the hydrolyzable group of the hydrolyzable silane coupling agent is hydrolyzed, and the hydrolyzable silane coupling agents are condensed to form a crosslinked structure.

  Condensation between hydrolyzable silane coupling agents proceeds only by storage at room temperature. Therefore, in the step (c), it is not necessary to positively contact the molded body (uncrosslinked body) with water. It can also be contacted with moisture to accelerate crosslinking. For example, it is possible to employ a method of positively contacting water, such as immersion in warm water, charging into a wet heat tank, exposure to high-temperature steam, and the like. In this case, pressure may be applied to allow moisture to penetrate inside.

  Thus, the manufacturing method of the heat resistant silane crosslinked resin molding of this invention is implemented, and a heat resistant silane crosslinked resin molding is manufactured from the heat resistant silane crosslinking resin composition of this invention. Therefore, the heat-resistant silane cross-linked resin molded product of the present invention is a molded product obtained by carrying out the step (a), the step (b) and the step (c).

The details of the reaction mechanism of the production method of the present invention are not yet clear, but are considered as follows.
That is, the resin (R) is at or above the decomposition temperature of the organic peroxide (P) together with the inorganic filler (B) and the hydrolyzable silane coupling agent (S) in the presence of the organic peroxide (P) component. When heated and kneaded, the organic peroxide (P) is decomposed to generate radicals, and the resin (R) is grafted by the hydrolyzable silane coupling agent (S). At this time, in part, the reaction of forming a chemical bond by a covalent bond between the hydrolyzable silane coupling agent (S) and a group such as a hydroxyl group on the surface of the inorganic filler (B) is also promoted by heating. The
In the present invention, in the step (c), a final crosslinking reaction may be performed. When a specific amount of the hydrolyzable silane coupling agent (S) is blended in the resin (R) as described above, extrusion during molding is performed. It becomes possible to mix a large amount of the inorganic filler (B) without impairing processability, and it is possible to have both heat resistance and mechanical properties while ensuring excellent flame retardancy.

  Moreover, although the mechanism of the operation of the above process of the present invention is not yet clear, it is estimated as follows. That is, by using the inorganic filler (B) and the hydrolyzable silane coupling agent (S) before and / or during kneading with the resin (R), the hydrolyzable silane coupling agent during kneading ( While suppressing the volatilization of S), it is possible to form a hydrolyzable silane coupling agent that binds to the inorganic filler (B) with a strong bond and a hydrolyzable silane coupling agent that binds with a weak bond.

In this way, the inorganic filler (B) to which the hydrolyzable silane coupling agent (S) is bonded is not less than the decomposition temperature of the organic peroxide (P) together with the resin (R) in the presence of the organic peroxide (P). In the hydrolyzable silane coupling agent (S), the hydrolyzable silane coupling agent having a strong bond with the inorganic filler (B) has an ethylenically unsaturated group as a resin ( A graft reaction is carried out at the cross-linked site of R). In particular, when a plurality of hydrolyzable silane coupling agents (S) are bonded to the surface of one inorganic filler (B) particle through a strong bond, the resin (R) is bonded via the inorganic filler (B) particle. Multiple will be joined. Thus, the crosslinked network with the inorganic filler (B) spreads.
The hydrolyzable silane coupling agent (S) having a strong bond with the inorganic filler (B) is a condensation reaction in the presence of water by the silanol condensation catalyst (C), and the surface of the inorganic filler (B). Hydrolyzable silane coupling agents that are chemically bonded to the hydroxyl groups of these groups also undergo a condensation reaction, further expanding the network of crosslinking.

  On the other hand, among the hydrolyzable silane coupling agent (S), the hydrolyzable silane coupling agent having a weak bond with the inorganic filler (B) is detached from the surface of the inorganic filler (B), and the hydrolyzable silane cup. The ethylenically unsaturated group, which is a crosslinking group of the ring agent (S), reacts with the resin radical generated by the extraction of the hydrogen radical by the radical generated by the decomposition of the organic peroxide (P) of the resin (R) to graft. A reaction takes place. The hydrolyzable silane coupling agent (S) in the graft portion thus produced is then mixed with the silanol condensation catalyst (C) and brought into contact with moisture to cause a crosslinking reaction by a condensation reaction.

In particular, in the present invention, after the conventional final cross-linking reaction is performed, the cross-linking reaction by the condensation using the silanol condensation catalyst (C) in the presence of water in this step (c) is performed. Compared with the method of forming the film, the workability in the process up to the formation of the molded body is excellent. Furthermore, a plurality of hydrolyzable silane coupling agents (S) can be bonded to the surface of a single inorganic filler (B) particle, so that higher heat resistance than before can be obtained and high mechanical strength can be obtained. Can do.
Thus, the hydrolyzable silane coupling agent (S) bonded to the inorganic filler (B) with a strong bond contributes to high mechanical properties, and the hydrolyzed silane coupling agent bonded to the inorganic filler (B) with a weak bond. The degradable silane coupling agent (S) is considered to contribute to the improvement of the degree of crosslinking, that is, the improvement of heat resistance.

In the present invention, when an inorganic filler (B) having a large BET specific surface area is used, the proportion of the hydrolyzable silane coupling agent (S) that strongly binds to the inorganic filler (B) increases, and the resin (R) is bonded to each other. Cross-linking is less likely to occur. On the other hand, when an inorganic filler (B) having a small BET specific surface area is used, the proportion of the hydrolyzable silane coupling agent (S) that binds strongly to the inorganic filler (B) decreases, and mechanical properties may deteriorate. .
As described above, in the present invention, when a large amount of hydrolyzable silane coupling agent having a weak bond with the inorganic filler (B) is produced, a molded article having a high degree of crosslinking can be obtained, and the hydrolyzability having a weak bond. By controlling the amount of the silane coupling agent to be small, the degree of cross-linking is lowered and a molded article having high flexibility can be obtained.

  In the present invention, the inorganic filler (B) has a BET specific surface area in the above-mentioned range, and is hydrolyzable that weakly binds to the hydrolyzable silane coupling agent (S) that binds strongly to the inorganic filler (B). The silane coupling agent (S) is formed with a good balun within a range in which heat resistance and mechanical properties are compatible. Therefore, volatilization of the hydrolyzable silane coupling agent can be suppressed, and a molded article excellent in mechanical properties, heat resistance, flame retardancy and appearance can be obtained.

  Moreover, when the mixing ratio of the hydrolyzable silane coupling agent (S) with respect to the inorganic filler (B) is increased, more hydrolyzable silane coupling agents (S) having a strong bond with the inorganic filler (B) are formed. . Therefore, when too much hydrolyzable silane coupling agent is mixed, it is difficult to increase the crosslink density of the molded body.

  On the other hand, when the hydrolyzable silane coupling agent is mixed with the filler that has been treated in advance with a large amount of the hydrolyzable silane coupling agent, the hydrolyzable silane coupling agent mixed later is pre-coated. Since it bonds with the degradable silane coupling agent, it becomes impossible to form a hydrolyzable silane coupling agent that binds to the filler with a weak bond. Therefore, when a hydrolyzable silane coupling agent is mixed with a filler that has been treated with a large amount of a hydrolyzable silane coupling agent in advance, the degree of cross-linking with the resulting resin composition and molded product is reduced, and heat resistance is improved. I can't let you.

The manufacturing method of the present invention can be applied to the manufacture of components (including semi-finished products, parts, and members) that require heat resistance, products that require strength, component parts of products such as rubber materials, or members thereof. it can. Examples of such products include electric wires such as heat-resistant flame-retardant insulated wires, heat-resistant and flame-resistant cable coating materials, rubber substitute electric wires and cable materials, other heat-resistant and flame-resistant electric wire components, flame-resistant and heat-resistant sheets, and flame-resistant and heat-resistant films. Can be mentioned. Also for the production of power plugs, connectors, sleeves, boxes, tape substrates, tubes, sheets, packing materials, cushioning materials, anti-vibration materials, electrical and electronic equipment, and wiring materials, especially electric wires and optical cables. Can be applied. The manufacturing method of the present invention is particularly suitably applied to the manufacture of the insulators and sheaths of electric wires and optical cables among the components of the above-described products, and can be formed as a covering thereof.
Insulators, sheaths, and the like can be formed by coating them in such a shape while melt-kneading them in an extrusion coating apparatus. For such molded products such as insulators and sheaths, a general-purpose extrusion coating apparatus is used without using a special machine such as an electron beam cross-linking machine, which is a high heat resistant high temperature non-melting cross-linked composition to which a large amount of inorganic filler is added. Can be formed by extrusion coating around the conductor, or around the conductor that has been stretched or twisted with tensile strength fibers. For example, any conductor such as an annealed copper single wire or stranded wire can be used as the conductor. In addition to the bare wire, the conductor may be tin-plated or an enamel-covered insulating layer. The thickness of the insulating layer (the coating layer made of the heat-resistant resin composition of the present invention) formed around the conductor is not particularly limited, but is usually about 0.15 to 8 mm.

EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these. In Tables 3 to 5, numerical values in Examples , Reference Examples, and Comparative Examples represent parts by mass unless otherwise specified.

Examples 1 to 3, Reference Examples 1 to 25, and Comparative Examples 1 to 9 were carried out using the components described in Tables 1 to 5 and changing respective specifications or production conditions.

In addition, the following were used as each compound shown in Tables 1-5.
<Resin (R)>
Resin R1: “UE320” (Novatech PE (trade name), linear low density polyethylene (PE), manufactured by Nippon Polyethylene, density 0.92 g / cm ³ )
Resin R2: “Evolue SP0540” (trade name, linear metallocene polyethylene (LLDPE) manufactured by Prime Polymer, density 0.9 g / cm ³ )
Resin R3: “EV460” (trade name, ethylene / vinyl acetate copolymer resin (VA content 14 mass%) manufactured by Mitsui DuPont Chemical Co., Ltd., density 0.93 g / cm ³ )
Resin R4: “EV170” (trade name, ethylene / vinyl acetate copolymer resin (VA content 33% by mass) manufactured by Mitsui DuPont Chemical Co., Ltd., density 0.96 g / cm ³ )
Resin R5: “NUC6510” (trade name, ethylene ethyl acrylate resin (EA content 23 mass%) manufactured by Nippon Unicar Co., Ltd., density 0.93 g / cm ³ )

<Hydrolyzable silane coupling agent (S)>
“KBM1003” (trade name): vinyltrimethoxysilane <organic peroxide (P)> manufactured by Shin-Etsu Chemical Co., Ltd.
“Perkadox BC-FF” (trade name): Di-α-cumyl peroxide manufactured by Kayaku Akzo (decomposition temperature 151 ° C.)
<Silanol condensation catalyst (C)>
“ADEKA STAB OT-1” (trade name): Dioctyltin laurate manufactured by ADEKA <carrier resin>
The above-mentioned “UE320” (product name)

<Inorganic filler (B)>
As the inorganic filler (B), “inorganic fillers B1 to B8 and 1” shown in Table 1 were prepared as follows.
First, surface-untreated synthetic magnesium hydroxide was pulverized with a ball mill, classified with a sieve, the BET specific surface area and volume average diameter were adjusted, and inorganic fillers B1 to B3 and 1 were obtained.
Similarly, synthetic magnesium hydroxide that has been wet-treated in advance by the amount of treatment shown in Table 1 with a silane coupling agent was pulverized and classified to obtain inorganic fillers B4 to B6.
Furthermore, the synthetic magnesium hydroxide wet-treated in advance by the treatment amount shown in Table 1 with the fatty acid “oleic acid” was pulverized and classified to obtain an inorganic filler B7.
Further, natural magnesium hydroxide that had been wet-treated in advance by the amount of treatment shown in Table 1 with fatty acid “stearic acid” was pulverized and classified to obtain inorganic filler B8.

As the inorganic filler B9, aluminum hydroxide “Hijilite 42H” (trade name, manufactured by Showa Denko KK) was used.
Further, inorganic filler B10 is synthesized by mixing aluminum hydroxide “Hijilite 42H” (trade name, manufactured by Showa Denko KK) and 1.0 mass% of silane coupling agent “KBM1003” with respect to this aluminum hydroxide. did.
As the inorganic filler B11, “Softon 1200” (trade name, manufactured by Shiraishi Calcium Co., Ltd., calcium carbonate) was used.
Further, as the inorganic filler B12, calcium carbonate “Whiteon SB Blue” (trade name, manufactured by Shiraishi Calcium Co., Ltd.), which has been surface-treated with a fatty acid at a treatment amount of 2.0 mass%, was used.
As the inorganic filler B13, “BF-300” (trade name, manufactured by Shiraishi Calcium Co., Ltd., calcium carbonate) was used.

The following were used as inorganic fillers other than the inorganic filler (B).
As the inorganic filler 2, “Aerosil 50” (silica, trade name, manufactured by Evonik Degussa)
As inorganic filler 3, “D-1000” (talc, trade name, manufactured by Nippon Talc Co., Ltd.)

  The BET specific surface area and volume average diameter of each of the inorganic fillers B1 to B13 and the inorganic fillers 1 to 3 were measured as described above. The results are shown in Table 1.

  For inorganic fillers B4 and B5, the number average diameter (MN), area average diameter (MA), 10% diameter, 50% diameter (cumulative average diameter) and 90% diameter were measured in the same manner as the volume average diameter measurement. And shown in Table 2.

In Examples , Reference Examples and Comparative Examples, 5 parts by mass of 100 parts by mass of the resin (R) was used as a carrier resin for the catalyst masterbatch.

(Examples 1 to 3, Reference Examples 1 to 22 and Comparative Examples 1 to 9)
First, the mass ratio shown in the “silane coupling agent” column of Table 3 and Table 4 with respect to 100 parts by mass of the inorganic fillers (B1 to B13 and 1-3) described in Tables 3 and 4 and 100 parts by mass of the inorganic filler ( The hydrolyzable silane coupling agent (S) “KBM1003” was mixed in a 10-liter ribbon blender manufactured by Toyo Seiki (by this, a silane coupling agent mixed inorganic filler (SF) was obtained) Then, at temperatures below the decomposition temperature of the organic peroxide (P), specifically at room temperature (25 ° C.), “organic peroxide ( The organic peroxide (P) having a mass ratio (part by mass) shown in “P)” was put into a closed ribbon blender and mixed at room temperature (25 ° C.) for 5 minutes to obtain a mixture.

  Next, the obtained mixture and 95 parts by mass of the resin (R) shown in Tables 3 and 4 were put into a 2 L Banbury mixer manufactured by Nippon Roll, and a temperature equal to or higher than the decomposition temperature of the organic peroxide (P). Specifically, after kneading at 180 to 190 ° C. for about 12 minutes, the material was discharged at a material discharge temperature of 180 to 190 ° C. to obtain a silane master batch (step (1)). The obtained silane masterbatch contains at least two silane crosslinkable resins obtained by graft-reacting the hydrolyzable silane coupling agent (S) to the resin (R).

On the other hand, 5 parts by mass of carrier resin “UE320” and 0.1 part by mass of silanol condensation catalyst (C) are separately melt-mixed at 180 to 190 ° C. with a Banbury mixer, and discharged at a material discharge temperature of 180 to 190 ° C. A catalyst master batch was obtained (step (2)).
This catalyst masterbatch is a mixture of carrier resin (E) and silanol condensation catalyst (C).

Next, the silane masterbatch and the catalyst masterbatch are shown in Tables 3 and 4 at a ratio of 95 parts by mass of the resin (R) of the silane masterbatch and 5 parts by mass of the carrier resin of the catalyst masterbatch. The mixture was melted and mixed at 180 ° C. with a Banbury mixer (step (3)). Thus, the process (a) was performed and the heat-resistant silane crosslinkable resin composition was prepared.
This heat-resistant silane crosslinkable resin composition is a mixture of a silane masterbatch and a catalyst masterbatch, and contains at least two kinds of silane crosslinkable resins described above.

Next, this heat-resistant silane crosslinkable resin composition was introduced into a 40 mm extruder (compressor screw temperature 190 ° C., head temperature 200 ° C.) with L / D = 24, and the thickness was increased outside the 1 / 0.8 TA conductor. An electric wire having an outer diameter of 2.8 mm was obtained by coating with 1 mm (step (b)).
The obtained electric wire was left in an atmosphere of temperature 80 ° C. and humidity 95% for 24 hours (step (c)).
Thus, the electric wire which has the coating | cover consisting of a heat resistant silane crosslinked resin molding was manufactured.

( Reference Example 23 )
A silane masterbatch and a catalyst masterbatch were prepared in the same manner as in Example 1 except that each component shown in Table 5 was used in the mass ratio (parts by mass) shown in the same table (Step (1) and Step ( 2)).
Subsequently, the obtained silane masterbatch and catalyst masterbatch were put into a closed ribbon blender, and dry blended at room temperature (25 ° C.) for 5 minutes to obtain a dry blend. At this time, the mixing ratio of the silane masterbatch and the catalyst masterbatch is such that the resin (R) in the silane masterbatch is 95 parts by mass and the carrier resin of the catalyst masterbatch is 5 parts by mass (see Table 5). did. Next, this dried blend was put into a 40 mm extruder (compressor screw temperature 190 ° C., head temperature 200 ° C.) with L / D = 24, and 1 / 0.8 TA while melt mixing in the extruder screw. The outside of the conductor was coated with a thickness of 1 mm to obtain an electric wire having an outer diameter of 2.8 mm (step (3) and step (b)).
The obtained electric wire was left in an atmosphere of a temperature of 80 ° C. and a humidity of 95% for 24 hours (step (c)).
Thus, the electric wire which has the coating | cover consisting of a heat resistant silane crosslinked resin molding was manufactured.

( Reference Example 24 )
An electric wire (outer diameter) in which the outer periphery of the conductor was coated with a heat-resistant silane crosslinkable resin composition in the same manner as in Example 1 except that each component shown in Table 5 was used in the mass ratio (part by mass) shown in the same table. 2.8 mm) was obtained (step (a) and step (b)).
The obtained electric wire was left in an atmosphere at a temperature of 23 ° C. and a humidity of 50% for 72 hours (step (c)).
Thus, the electric wire which has the coating | cover consisting of a heat resistant silane crosslinked resin molding was manufactured.

( Reference Example 25 )
A silane masterbatch was prepared in the same manner as in Example 1 except that each component shown in Table 5 was used in the mass ratio (parts by mass) shown in the same table (step (1)).
On the other hand, 5 parts by mass of carrier resin “UE320” and 0.1 part by mass of silanol condensation catalyst (C) were melt-mixed with a twin-screw extruder to obtain a catalyst master batch (step (2)). The screw diameter of the twin screw extruder was set to 35 mm, and the cylinder temperature was set to 180 to 190 ° C. The obtained catalyst masterbatch is a mixture of carrier resin (E) and silanol condensation catalyst (C).
Subsequently, the obtained silane master batch and catalyst master batch were melt-mixed at 180 ° C. by a Banbury mixer to obtain a mixture (step (3)). The mixing ratio of the silane masterbatch and the catalyst masterbatch was such that the resin (R) in the silane masterbatch was 95 parts by mass and the carrier resin of the catalyst masterbatch was 5 parts by mass (see Table 5). Thus, the process (a) was performed and the heat-resistant silane crosslinkable resin composition was prepared. This heat-resistant silane crosslinkable resin composition is a mixture of a silane masterbatch and a catalyst masterbatch, and contains at least two kinds of silane crosslinkable resins described above.
Next, this heat-resistant silane crosslinkable resin composition was introduced into a 40 mm extruder (compressor screw temperature 190 ° C., head temperature 200 ° C.) with L / D = 24, and the thickness was increased outside the 1 / 0.8 TA conductor. An electric wire having an outer diameter of 2.8 mm was obtained by coating with 1 mm (step (b)).
The obtained electric wire was left in a state where it was immersed in hot water having a temperature of 50 ° C. for 10 hours (step (c)).
Thus, the electric wire which has the coating | cover consisting of a heat resistant silane crosslinked resin molding was manufactured.

As described above, the heat-resistant silane cross-linked resin molded products obtained in the above Examples and Reference Examples are crosslinked by the condensation reaction of the hydrolyzable group of the hydrolyzable silane coupling agent as described above. The above-mentioned silane cross-linked resin is contained.

  The manufactured wires were evaluated as follows, and the results are shown in Tables 3 to 5.

<Mechanical properties>
A tensile test was conducted as a mechanical property of the electric wire. This tensile test was performed according to JIS C 3005. Using the electric wire tubular piece from which the conductor was extracted from the electric wire, the tensile strength (unit: MPa) and the tensile elongation (%) were measured at 25 mm between the marked lines and at a tensile speed of 200 mm / min.
The tensile strength is evaluated as “A” when the tensile strength is 10 MPa or more, “B” when it is 6.5 MPa or more and less than 10 MPa, “C” if it is less than 6.5 MPa, and “A” and “B”. Was passed.
In addition, the tensile elongation of 200% or more is “A”, 125% or more and 200% or less is “B”, less than 125% is “C”, and “A” and “B” are acceptable. .

<Heat resistance>
The heat resistance was performed in accordance with the “heat deformation test” defined in JIS C 3005. The load was 5N and the heating temperature was 160 ° C. A deformation rate of 40% or less was designated as “A” (pass), and a deformation rate greater than 40% was designated as “B”.

<Extrusion appearance characteristics of electric wire>
An extrusion appearance test was conducted as an extrusion appearance characteristic of the electric wire. The extrusion appearance was observed when the electric wire was produced. In addition, when it was produced with a 25 mm extruder at a linear speed of 10 m, it was “A” when the appearance was good, “B” when the appearance was slightly bad, and “C” when the appearance was remarkably bad. A ”and“ B ”were accepted as product levels.

<Long-term storability of silane coupling agent mixed inorganic filler (SF)>
As long-term storage properties of the silane coupling agent mixed inorganic filler (SF), after each silane coupling agent mixed inorganic filler prepared in step (a) in each of the Examples , Reference Examples and Comparative Examples was stored for a long time , Similarly to the reference example and the comparative example, the step (a), the step (b), and the step (c) were performed to produce an electric wire, and an extrusion appearance test of the electric wire at this time was performed. The silane coupling agent mixed inorganic filler was stored at 40 ° C. for 6 months, and packed in an aluminum bag after preparation. In addition, mechanical properties and heat resistance were evaluated in the same manner as in the above-described Examples , Reference Examples, and Comparative Examples.
The evaluation criteria were “A” when the appearance was good when manufactured with a 25 mm extruder at a linear speed of 10 m, and the evaluation of mechanical characteristics and heat resistance was not changed. “B” means that there was no problem above, “C” means that the appearance was remarkably bad, or at least one of the evaluation of mechanical properties and heat resistance was reduced, and “A” and “B” were passed. did.

As is clear from the results in Tables 3 to 5, Examples 1 to 3 and Reference Examples 1 to 25 all passed in mechanical properties, heat resistance, and extrusion appearance. That is, it turns out that the heat-resistant silane crosslinked resin molded body of the present invention provided as a coating for the wires of Examples 1 to 3 and Reference Examples 1 to 25 is excellent in all of mechanical properties, heat resistance and appearance. It was. In addition, it can be easily estimated that the flame retardancy is excellent from the amount of the inorganic filler (B) mixed.
Thus, according to the present invention, volatilization of the hydrolyzable silane coupling agent can be suppressed even if the hydrolyzable silane coupling agent is melt-mixed in the ribbon blender in the step (1), and excellent mechanical properties, It turned out that the heat-resistant silane crosslinked resin molding which has a flame retardance and an external appearance can be manufactured.
On the other hand, Comparative Examples 1-9 were inferior in at least any one of a mechanical characteristic, heat resistance, and an external appearance, and could not satisfy all these. In particular, Comparative Example 5 foamed in terms of extrusion appearance characteristics and long-term storage, and was inferior in appearance.

  Further, the silane coupling agent mixed inorganic filler of the present invention has a change in mechanical properties, heat resistance and appearance as compared with the case where it is used immediately after the preparation even after being stored at 40 ° C. for 6 months. It was found that it can be stored for a long time.

Claims (13)

100 parts by mass of resin (R), 0.01 to 0.6 parts by mass of organic peroxide (P), 10 to 400 parts by mass of inorganic filler (B) having a BET specific surface area of 14 m ² / g or less, Hydrolyzable silane coupling having a group capable of chemically bonding to the inorganic filler (B) and a group capable of grafting to the resin (R) in the presence of a radical with respect to 100 parts by mass of the inorganic filler (B). 0.5 to 15.0 parts by mass of the agent (S) and a silanol condensation catalyst (C) are melt-mixed, and the group capable of undergoing the graft reaction by radicals generated from the organic peroxide is converted into the resin (R). (A) to obtain a heat-resistant silane crosslinkable resin composition containing a silane crosslinkable resin by graft reaction
A step (b) of molding the heat-resistant silane crosslinkable resin composition;
A step (c) of obtaining a heat-resistant silane-crosslinked resin molded product by contacting the obtained molded product with water,
The step (a) includes the following step (1) and step (3). However, when a part of the resin (R) is melt-mixed in the following step (1), the following step (2) is further included. And
Step (1): All or part of the resin (R), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent (S) are combined with the organic peroxide. object(
A silane masterbatch containing a silane crosslinkable resin by melting and mixing at a decomposition temperature of P) or more and causing the resin (R) to graft-react the graftable group with radicals generated from the organic peroxide. Step (2): The step of preparing a catalyst master batch by melt-mixing the remainder of the resin (R) and the silanol condensation catalyst (C) Step (3): The silane master batch and the silanol Step of mixing the condensation catalyst (C) or the catalyst master batch to obtain a heat-resistant silane crosslinkable resin composition At least one of the inorganic fillers (B) is a fatty acid surface-treated inorganic filler.
A method for producing a heat-resistant silane-crosslinked resin molded product.   In the step (1), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent (S) at a temperature lower than the decomposition temperature of the organic peroxide (P). Then, the obtained mixture and all or a part of the resin (R) are melt-mixed at a temperature equal to or higher than the decomposition temperature of the organic peroxide (P). Manufacturing method of resin molding.   The manufacturing method of the heat resistant silane crosslinked resin molding of Claim 1 or 2 in which the said inorganic filler (B) has a volume average diameter of 5 micrometers or less.   The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of claims 1 to 3, wherein the resin (R) is mixed in both steps (1) and (2).   The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of claims 1 to 4, wherein the fatty acid surface-treated inorganic filler is a fatty acid surface-treated metal hydrate.   The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of claims 1 to 5, wherein the fatty acid surface-treated inorganic filler is fatty acid surface-treated magnesium hydroxide. The method for producing a heat-resistant silane-crosslinked resin molded article according to any one of claims 1 to 4 , wherein the fatty acid surface-treated inorganic filler is fatty acid surface-treated calcium carbonate.   The manufacturing method of the heat-resistant silane crosslinked resin molding of any one of Claims 1-7 with which the said process (1) is performed with an airtight mixer. 100 parts by mass of resin (R), 0.01 to 0.6 parts by mass of organic peroxide (P), 10 to 400 parts by mass of inorganic filler (B) having a BET specific surface area of 14 m ² / g or less, Hydrolyzable silane coupling having a group capable of chemically bonding to the inorganic filler (B) and a group capable of grafting to the resin (R) in the presence of a radical with respect to 100 parts by mass of the inorganic filler (B). 0.5 to 15.0 parts by mass of the agent (S) and a silanol condensation catalyst (C) are melt-mixed, and the group capable of undergoing the graft reaction by radicals generated from the organic peroxide is converted into the resin (R). Having a step (a) of obtaining a heat-resistant silane crosslinkable resin composition containing a silane crosslinkable resin by grafting to
The step (a) includes the following step (1) and step (3). However, when a part of the resin (R) is melt-mixed in the following step (1), the following step (2) is further included. And
Step (1): All or part of the resin (R), the organic peroxide (P), the inorganic filler (B), and the hydrolyzable silane coupling agent (S) are combined with the organic peroxide. object(
A silane masterbatch containing a silane crosslinkable resin by melting and mixing at a decomposition temperature of P) or more and causing the resin (R) to graft-react the graftable group with radicals generated from the organic peroxide. Step (2): The step of preparing a catalyst master batch by melt-mixing the remainder of the resin (R) and the silanol condensation catalyst (C) Step (3): The silane master batch and the silanol Step of mixing the condensation catalyst (C) or the catalyst master batch to obtain a heat-resistant silane crosslinkable resin composition At least one of the inorganic fillers (B) is a fatty acid surface-treated inorganic filler.
A method for producing a heat-resistant silane crosslinkable resin composition.   A heat-resistant silane crosslinkable resin composition produced by the production method according to claim 9.   A heat-resistant silane cross-linked resin molded product produced by the production method according to claim 1.   A heat-resistant product comprising the heat-resistant silane-crosslinked resin molded article according to claim 11.   The heat-resistant product according to claim 12, wherein the heat-resistant silane cross-linked resin molded body is provided as a coating for an electric wire or an optical fiber cable.