JP2018172515A - Silane-crosslinked resin molded body and method for producing the same, silane masterbatch, masterbatch mixture and molded body of the same, and heat-resistant product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silane-crosslinked resin molded body which can be produced while reducing occurrence of gum (resin scum) during molding, is excellent in appearance and has desired heat resistance and a method for producing the same, a silane masterbatch from which the silane-crosslinked resin molded body can be formed, a mixture and a molded body of the same, and a heat-resistant product.SOLUTION: There are provided a production method which includes a step (a) of melting and mixing a polyolefin-based base resin or rubber, an acrylic polymer, an organic peroxide, an inorganic filler and a silane coupling agent in a specific ratio at a temperature equal to or higher than a decomposition temperature of the organic peroxide to prepare a silane masterbatch, and a step (b) of mixing the silane masterbatch obtained in the step (a) and a silanol condensation catalyst and then molding the mixed substance; a silane-crosslinked resin molded body produced by the same; a silane masterbatch; a mixture and a molded body of the same; and a heat-resistant product.SELECTED DRAWING: None

Description

  The present invention relates to a silane cross-linked resin molded article and a method for producing the same, a silane master batch, a master batch mixture and a molded article thereof, and a heat-resistant product.

  Resin or rubber products such as coating materials for various industrial cables (including electric wires), rubber molding materials (for example, glass run channels for automobiles, weather strips, rubber hoses, wiper blade rubbers, anti-vibration rubbers) have heat resistance. Various characteristics are required.

Examples of the material of the resin or rubber product include polyolefin resins.
Examples of the method for producing the resin or rubber product include injection molding, mold molding, and extrusion molding. Among them, extrusion molding is widely performed in the production of the resin or rubber product.
When extrusion molding is performed using a base resin containing a polyolefin-based resin, there is a problem that resin scum (die scum) called “Mayani” accumulates in the die portion of the extruder with the lapse of molding time and impairs extrusion moldability. . Specifically, the die casks drop off from the die part and mix into the molded body to impair the characteristics of the molded body, touch the molded body at the time of extrusion, impair the appearance, and stop the extruder to remove the die scum for a long time. There is a problem that continuous molding is difficult.

  As a production method for reducing the occurrence of sag during the above extrusion molding, Patent Document 1 includes a polyolefin-based resin, magnesium hydroxide surface-treated with a highly heavy polyorganosiloxane, and a methyl methacrylate polymer. A method for producing a molded body using the resin composition is described. Patent Document 3 proposes a method for manufacturing a flexible tube made of a resin composition containing a chlorine-containing resin and an acrylic polymer resin. Patent Document 2 discloses a halogen-free flame retardant in which a metal hydrate, an acrylic processing aid and a fatty acid amide lubricant are added to a base resin composed of a crosslinked ethylene-vinyl acetate copolymer and a crystalline polyolefin. A manufacturing method using a resin composition has been proposed.

Further, in the molded product as described above, the resin forming the product may be cross-linked in order to improve characteristics such as heat resistance. Examples of the resin crosslinking method include an electron beam crosslinking method and a chemical crosslinking method. Among chemical cross-linking methods, the silane cross-linking method is advantageous in production as compared with other cross-linking methods because no special equipment is required in the cross-linking step.
The silane crosslinking method is a method in which a hydrolyzable silane coupling agent having an unsaturated group is grafted to a resin in the presence of an organic peroxide to obtain a silane graft resin, and then the silane grafting in the presence of a silanol condensation catalyst. This is a method of crosslinking a resin by bringing the resin into contact with moisture.

JP 2006-8873 A JP 2011-195831 A JP 2015-166608 A

Since the manufacturing methods described in Patent Document 1 and Patent Document 3 do not perform crosslinking, it is difficult to obtain a molded body having desired heat resistance.
Moreover, in the manufacturing method described in Patent Document 2, since the network formation in the base resin is insufficient, it is difficult to obtain a molded body having desired heat resistance.
Moreover, the molded object by the conventional silane crosslinking method was not fully crosslinked, and there was room for improvement in terms of heat resistance. In addition, during molding, a hump (also referred to as gel or flaw) tends to occur on the surface of the molded body, and there is a problem with the appearance of the molded body.

The present invention provides a silane-crosslinked resin molded article that overcomes the above-mentioned problems, can be produced by reducing the occurrence of scum (resin residue) during molding, has excellent appearance and has desired heat resistance, and a method for producing the same. Let it be an issue.
Moreover, this invention makes it a subject to provide the silane masterbatch which can form this silane crosslinked resin molded object, a masterbatch mixture, and its molded object.
Furthermore, this invention makes it a subject to provide the heat resistant product containing said silane crosslinked resin molded object.

  In the silane cross-linking method, the present inventors use a mixture containing an acrylic polymer, an organic peroxide, an inorganic filler, and a silane coupling agent in a specific ratio with respect to a polyolefin base resin or rubber. Melting and kneading at a temperature above the decomposition temperature of the mixture, mixing the resulting composition with a silanol condensation catalyst, and a specific manufacturing method that includes a molding step, can reduce the occurrence of burrs during molding, and is excellent in heat resistance and appearance It was found that a silane cross-linked resin molded product can be produced. Based on this finding, the present inventors have made further studies and have come up with the present invention.

That is, the subject of this invention was achieved by the following means.
[1] 0.1 to 20 parts by mass of an acrylic polymer, 0.003 to 0.3 parts by mass of an organic peroxide, and 0.5 to 0.5 parts of an inorganic filler with respect to 100 parts by mass of the polyolefin base resin or rubber. (A) a step of preparing a silane masterbatch by melt-mixing 400 parts by weight and 2 parts by weight of a silane coupling agent to 15.0 parts by weight or less at a temperature equal to or higher than the decomposition temperature of the organic peroxide; ,
A step (b) of molding after mixing the silane masterbatch obtained in the step (a) and a silanol condensation catalyst;
A step (c) of bringing the molded product obtained in the step (b) into contact with moisture and crosslinking;
The manufacturing method of the silane crosslinked resin molding which has this.
[2] The method for producing a silane-crosslinked resin molded product according to [1], wherein the acrylic polymer has a mass average molecular weight of 100,000 to 1,000,000.
[3] The method for producing a silane-crosslinked resin molded article according to [1] or [2], wherein the acrylic polymer is 0.5 to 10 parts by mass with respect to 100 parts by mass of the polyolefin base resin or rubber. .
[4] The silane cross-linked resin molded article according to any one of [1] to [3], wherein the acrylic polymer is 1 to 6 parts by mass with respect to 100 parts by mass of the polyolefin base resin or rubber. Manufacturing method.
[5] The method for producing a silane-crosslinked resin molded article according to any one of [1] to [4], wherein the silane coupling agent is vinyltrimethoxysilane or vinyltriethoxysilane.
[6] In any one of [1] to [5], the inorganic filler is at least one selected from the group consisting of silica, boehmite, clay, talc, aluminum hydroxide, magnesium hydroxide, and calcium carbonate. The manufacturing method of the silane crosslinked resin molded object of description.
[7] The method for producing a silane-crosslinked resin molded article according to any one of [1] to [6], wherein the melt mixing in the step (a) is performed using a closed mixer.
[8] 0.1 to 20 parts by mass of an acrylic polymer, 0.003 to 0.3 parts by mass of an organic peroxide, and 0.5 to 400 inorganic fillers with respect to 100 parts by mass of the polyolefin base resin or rubber. A silane masterbatch used for producing a masterbatch mixture obtained by mixing a mass part, a silane coupling agent exceeding 2 parts by mass and 15.0 parts by mass or less, and a silanol condensation catalyst,
A silane master batch obtained by melting and mixing all or part of the base resin, the organic peroxide, the inorganic filler, and the silane coupling agent at a temperature equal to or higher than the decomposition temperature of the organic peroxide.
[9] A master batch mixture containing the silane master batch according to [8] and a silanol condensation catalyst.
[10] A molded article formed by introducing a master batch mixture obtained by dry blending the silane master batch according to [9] and a silanol condensation catalyst into a molding machine.
[11] A silane cross-linked resin molded product produced by the method for producing a silane cross-linked resin molded product according to any one of [1] to [7].
[12] The silane crosslinked resin molded article according to [11], wherein the base resin is crosslinked with the inorganic filler through a silanol bond.
[13] A heat-resistant product comprising the silane cross-linked resin molded article according to [11] or [12].

  In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

According to the present invention, it is possible to produce a silane cross-linked resin molded article having excellent heat resistance and appearance, which overcomes the above-described problems and reduces the occurrence of mess during molding.
Therefore, according to the present invention, a silane cross-linked resin molded article having excellent heat resistance and appearance and a method for producing the same can be provided. Moreover, the silane masterbatch which can form the silane crosslinked resin molded object which shows such an outstanding characteristic, a masterbatch mixture, and its molded object can be provided. Furthermore, it is possible to provide a heat-resistant product including a silane cross-linked resin molded article exhibiting excellent characteristics.

Hereinafter, preferred embodiments of the present invention will be described.
First, each component used in the present invention will be described.

<Polyolefin base resin or rubber>
The polyolefin base resin or rubber (hereinafter also referred to as base resin) contains a polyolefin resin or rubber. It does not specifically limit as polyolefin-type resin or rubber | gum, For example, the following can be used.
The base resin may contain a styrene thermoplastic elastomer and mineral oil in addition to the polyolefin resin or rubber.

(A1) Resin of ethylene-α-olefin copolymer Examples of the ethylene-α-olefin copolymer include a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms. Although it does not specifically limit as an alpha olefin, 1-propylene, 1-butene, 1-hexene, 4-methyl-1- pentene, 1-octene, 1-decene, 1-dodecene etc. are mentioned.
Here, the ethylene-α-olefin copolymer is one having an ethylene component content of about 80 to 99% by mass.
Examples of the ethylene-α-olefin copolymer include LDPE (low density polyethylene), LLDPE (linear low density polyethylene), MDPE (medium density polyethylene), or a polyethylene resin synthesized in the presence of a metallocene catalyst. Among these, LLDPE synthesized in the presence of a metallocene catalyst is preferable.
The density of the ethylene -α- olefin copolymer is preferably ^{0.880~0.940g / cm 3, 0.900~0.930g / cm} 3 is more preferable. When the density is 0.880 to 0.940 g / cm ³ , excellent mechanical properties can be obtained. Further, when the base resin contains mineral oil, the mineral oil is difficult to bleed out and the appearance of the molded body can be maintained for a long time. The density of the ethylene-α-olefin copolymer can be measured by the method described in JIS K7112.
Examples of the ethylene-α-olefin copolymer include “Kernel” (trade name, manufactured by Nippon Polyethylene Co., Ltd.), “Evolue” (trade name, manufactured by Prime Polymer Co., Ltd.), and “Sumikasen” (trade name, manufactured by Sumitomo Chemical Co., Ltd.). , “Engage” (trade name, manufactured by Dow).
The ethylene-α-olefin copolymer resin contained in the base resin may be one type or two or more types.

(A2) Ethylene-α-olefin copolymer rubber The ethylene-α-olefin copolymer rubber is not particularly limited as long as it is a rubber made of a copolymer of ethylene and the α-olefin. For example, ethylene-propylene copolymer rubber (EP rubber (EPM)), which is a rubber-like copolymer of ethylene and propylene. Here, the ethylene-propylene copolymer rubber means one having an ethylene component content of usually about 40 to 75% by mass. The ethylene component content in the ethylene-propylene copolymer rubber is preferably 50 to 75% by mass, more preferably 55 to 70% by mass. The ethylene component content is a value measured in accordance with the method described in ASTM D3900.

The ethylene-α-olefin copolymer rubber is an ethylene-propylene terpolymer having a repeating unit having an unsaturated group as a third component other than ethylene and α-olefin (propylene) (for example, ethylene, α-olefin and diene). And terpolymers (EPDM). In the present invention, either one or both of EPM and EPDM may be used as the ethylene-α-olefin copolymer rubber.
Examples of the ethylene-propylene copolymer rubber include “Mitsui EPT” (trade name, manufactured by Mitsui Chemicals) and “Nodel” (trade name, manufactured by Dow Chemical).
The ethylene-α-olefin copolymer rubber contained in the base resin may be one type or two or more types.

(A3) Ethylene-based copolymers other than ethylene-α-olefin copolymers Ethylene-based copolymers other than ethylene-α-olefin copolymers include ethylene-vinyl acetate copolymers and ethylene- (meth) acrylic. An acid ester copolymer, an ethylene- (meth) acrylic acid copolymer, or the like can be used alone or appropriately mixed. By using these ethylene copolymers, flame retardancy can be improved and flexibility can be imparted.
As the ethylene-based copolymer other than the ethylene-α-olefin copolymer, an ethylene-vinyl acetate copolymer and / or an ethylene- (meth) acrylate copolymer can be preferably used.

As long as the ethylene-vinyl acetate copolymer is a copolymer of ethylene and vinyl acetate, it may be an alternating copolymer obtained by alternately polymerizing an ethylene component and a vinyl acetate component. A block copolymer formed by combining a polymer block and a polymer block of a vinyl acetate component may be used, and further, a random copolymer in which an ethylene component and a vinyl acetate component are randomly polymerized may be used.
As the ethylene-vinyl acetate copolymer, it is preferable to use a vinyl acetate component having a content of 10 to 80% by mass. The content of the vinyl acetate component in the ethylene-vinyl acetate copolymer is preferably 12 to 70% by mass, more preferably 15 to 50% by mass, and still more preferably 17 to 45% by mass. You may combine 2 or more types of resin from which content of a vinyl acetate component differs.
Examples of the ethylene-vinyl acetate copolymer include Evaflex (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.) and Revaprene (trade name, manufactured by Bayer).

The ethylene- (meth) acrylic acid ester copolymer includes both an ethylene-acrylic acid ester copolymer and an ethylene-methacrylic acid ester copolymer. In the present specification, “ethylene- (Meth) acrylate copolymer ”.
If the ethylene- (meth) acrylic acid ester copolymer is a copolymer of ethylene and (meth) acrylic acid ester, the alternating copolymer and block copolymer are the same as the above-mentioned ethylene-vinyl acetate copolymer. Either a polymer or a random copolymer may be used. The (meth) acrylic acid ester component is not particularly limited, but preferably has an alkyl group having 1 to 4 carbon atoms, such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, etc. Is mentioned.

  The content of the (meth) acrylic acid ester component which is a copolymerization component of the ethylene- (meth) acrylic acid ester copolymer is preferably 10 to 40% by mass. When the content is in the above range, high tensile strength can be maintained and flame retardancy can be imparted.

Examples of the ethylene- (meth) acrylic acid ester copolymer include an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-methyl methacrylate copolymer, and an ethylene-ethyl methacrylate copolymer. Examples include coalescence.
Examples of the ethylene-acrylic acid ester copolymer include Elvalloy (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.).

Examples of the ethylene- (meth) acrylic acid copolymer include Nucrel (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.).
The ethylene copolymer other than the ethylene-α-olefin copolymer contained in the base resin may be one type or two or more types.

(A4) High-density polyethylene resin As the high-density polyethylene resin (HDPE), a polyethylene homopolymer or the like can be used.
Is not particularly limited density, preferably 0.965 g / cm ³ or less exceed 0.940, 0.945~0.960g / cm ³ is more preferable. The density of the high-density polyethylene resin can be measured by the method described in JIS K7112.
Moreover, although MFR (190 degreeC, 2.16 kg) also does not have a restriction | limiting in particular, 0.2-10 g / 10min is preferable and 0.8-5 g / 10min is more preferable. If it is too small, the motor load on the production equipment increases and the high-speed moldability may be poor.
Examples of the high-density polyethylene resin include “Hi-Zex” (trade name, manufactured by Prime Polymer Co., Ltd.), “Nipolon Hard” (trade name, manufactured by Tosoh Corporation), “Novatech” (trade name, manufactured by Nippon Polyethylene Co., Ltd.), and the like. it can.
The high density polyethylene resin contained in the base resin may be one type or two or more types.

(A5) Polypropylene resin As the polypropylene resin, a resin such as a propylene homopolymer (homopolypropylene resin), an ethylene-propylene random copolymer, or an ethylene-propylene block copolymer can be used.
Here, the ethylene-propylene random copolymer has a content of ethylene component of about 1 to 10% by mass, and the ethylene component is randomly incorporated into the propylene chain. The ethylene-propylene block copolymer has a total content of an ethylene component and an ethylene-propylene rubber (EPR) component of about 5 to 20% by mass, and the ethylene component and the EPR component are independently contained in the propylene component. This is an existing sea-island structure. Particularly preferred is an ethylene-propylene random copolymer from the viewpoint of the appearance of the molded product after extrusion.
The MFR (JIS K 7210, 230 ° C., 2.16 kg) of the polypropylene resin is preferably 0.5 to 50 g / 10 minutes, more preferably 0.5 to 30 g / 10 minutes, and further preferably 0.5 to 10 g. / 10 minutes. By blending such a polypropylene resin having an MFR value, the molecular weight distribution of the base resin component can be broadened, and the appearance of the molded body after extrusion molding can be improved.
One type of polypropylene may be used, or two or more types may be used in combination.
Examples of the polypropylene resin include “Sun Allomer PP” (trade name, manufactured by Sun Allomer), “Prime Polypro” (trade name, manufactured by Prime Polymer), “Novatech PP” (trade name, manufactured by Nippon Polypro), and the like. The polypropylene resin contained in the base resin may be one type or two or more types.

The content ratio of each component of the base resin is appropriately determined so that the total amount of each component such as the polyolefin resin or rubber, styrene thermoplastic elastomer and mineral oil described later is 100% by mass, preferably It is selected from the following range.
When the base resin contains an ethylene-α-olefin copolymer resin, the content of the ethylene-α-olefin copolymer resin in the base resin is preferably 20 to 100% by mass, and 30 to 80% by mass. % Is more preferable.

(A6) Styrenic thermoplastic elastomer Styrenic thermoplastic elastomer is a block copolymer or random copolymer elastomer derived from an aromatic vinyl compound and a conjugated diene compound, or a hydrogenated product thereof. Etc. The styrenic thermoplastic elastomer preferably contains 5-70% by mass of an aromatic vinyl compound, more preferably 10-60% by mass. This content is calculated | required by measuring a UV absorption spectrum, for example in the ultraviolet spectrophotometer using a chloroform solution.
As an aromatic vinyl compound, 1 type (s) or 2 or more types can be selected from styrene, (alpha) -methylstyrene, vinyltoluene, p-tert-butyl styrene, etc., for example, Styrene is especially preferable. As the conjugated diene compound, for example, one or more kinds are selected from butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, etc. Among them, butadiene, isoprene, and these A combination is preferred.

Examples of the styrenic thermoplastic elastomer include SBS (styrene-butadiene-styrene block copolymer), SIS (styrene-isoprene-styrene block copolymer), SEBS (styrene-ethylene-butylene-styrene block copolymer: hydrogenated SBS), SEEPS ( Styrene-ethylene-ethylene-propylene-styrene block copolymer), SEPS (styrene-ethylene-propylene-styrene block copolymer: hydrogenated SIS), HSBR (hydrogenated styrene-butadiene random copolymer), and the like.
As the styrenic thermoplastic elastomer, a binary or ternary copolymer composed of a polystyrene block and an elastomer block having a polyolefin structure can be used.
Examples of the styrenic thermoplastic elastomer include “Septon” (trade name, manufactured by Kuraray Co., Ltd.), “Tough Tech” (trade name, manufactured by Asahi Kasei Chemicals), and “Dynalon” (trade name, manufactured by JSR). it can.

  The styrenic thermoplastic elastomer contained in the base resin may be one type or two or more types.

  As content rate of a styrene-type thermoplastic elastomer, 10-40 mass% is preferable in 100 mass% of base resins. If it is the range of 10-40 mass%, while being able to provide a softness | flexibility, it is hard to generate | occur | produce especially a gel lump.

(A7) Mineral oil The mineral oil used in the present invention is a mixed oil including three oils: an oil having an aromatic ring, an oil having a naphthene ring, and an oil having a paraffin chain. Paraffinic oil means that the carbon number (CP) of the paraffin chain is, for example, 50% or more and less than 75% of the total carbon number of the aromatic ring, naphthene ring and paraffin chain, and the carbon number (CN) of the naphthene chain is 20 or more and less than 40%, and the number of carbon atoms of the aromatic ring (CA) occupies 3 or more and less than 10%. A naphthenic oil is one having CN of 40 to 60%, CP of 30% to less than 50%, and CA of 8% to less than 16% of the total carbon number. Means 16% or more.
The mineral oil is preferably paraffinic oil or naphthenic oil, and is preferably paraffinic oil in terms of mechanical strength.
The mineral oil preferably has a dynamic viscosity at 40 ° C. of ²⁰ to 500 mm ² / s, a pour point of −10 to −15 ° C., and a flash point (COC) of 180 to 300 ° C.
The content of the mineral oil is preferably 10 to 40% by mass in 100% by mass of the base resin. If it is in the range of 10 to 40% by mass, it is difficult to generate gel but also bleed out during molding. Therefore, it can be set as the molded object excellent in the external appearance.
Examples of the mineral oil include “Diana Process Oil” (trade name, manufactured by Idemitsu Kosan Co., Ltd.) and “Cosmo Neutral” (trade name, manufactured by Cosmo Oil Lubricants).

  From the viewpoint of obtaining a molded article having an excellent appearance, the base resin preferably contains an ethylene-α-olefin copolymer rubber, a styrene thermoplastic elastomer, and a mineral oil.

<Acrylic polymer>
As the acrylic polymer, a homopolymer or copolymer containing (meth) acrylic acid or (meth) acrylic acid ester as a component, that is, (meth) acrylic acid polymer, (meth) acrylic acid ester polymer, ( It is not particularly limited as long as it is a copolymer of (meth) acrylic acid and (meth) acrylic acid ester. What is used for manufacture of a resin molding can be used as an acrylic type processing aid.
As the (meth) acrylic acid ester, alkyl (meth) acrylate is preferable. The alkyl group of alkyl (meth) acrylate 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. Specific examples of the alkyl (meth) acrylate preferably include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and ethyl methacrylate. These can be used alone or in combination.
Although it does not specifically limit as a mass average molecular weight of an acryl-type polymer, Preferably it is 50,000-3 million, More preferably, it is 100,000-1 million, More preferably, it is 100,000-500,000. From the viewpoint of reducing the bleed out and maintaining the appearance of the molded article over a long period of time, a higher mass average molecular weight is preferable.
Here, the mass average molecular weight can be measured, for example, by GPC (Gel Permeation Chromatography) method using THF (tetrahydrofuran) as a developing solvent. Specifically, a calibration curve was created for the relationship between the peak position of the GPC spectrogram and the molecular weight for known polystyrene, and then the spectrogram of the acrylic polymer measured by GPC was compared with the calibration curve of polystyrene with a known molecular weight. It is calculated | required by calculating a polystyrene conversion mass mean molecular weight.
Examples of the acrylic polymer include Methbrene L-1000 (trade name, manufactured by Mitsubishi Rayon Co., Ltd.).

  By using the acrylic polymer, lubricity is imparted to the surface of the molded body, friction between the molded body and the die of the extruder is reduced, and the surface can be suppressed. In addition, since the acrylic polymer has high compatibility with the above polyolefin base resin or rubber, it helps to disperse various additives such as a silane coupling agent and an inorganic filler, thereby obtaining a molded article having good physical properties. Can do. In addition, when an acrylic polymer is used, the graft reaction is not inhibited or excessively promoted during the silane masterbatch production process, and the condensation reaction between silanol groups is suppressed. As a result, it is possible to suppress molding during extrusion without deteriorating physical properties such as heat resistance, and to obtain a molded article having a clean appearance.

<Organic peroxide>
The organic peroxide generates radicals by at least thermal decomposition, and serves as a catalyst to cause a graft reaction by radical reaction to the resin component of the silane coupling agent. In particular, when the reaction site of the silane coupling agent contains, for example, an ethylenically unsaturated group, a grafting reaction occurs due to a radical reaction between the ethylenically unsaturated group and the resin component (including a reaction of abstracting hydrogen radicals from the resin component). To work.
The organic peroxide is not particularly limited as long as it generates radicals. For example, the general formula: R ¹ —OO—R ² , R ³ —OO—C (═O) R ⁴ , R ⁵ C A compound represented by (═O) —OO (C═O) R ⁶ is preferred. Here, R ^{1 to} R ⁶ each independently represents an alkyl group, an aryl group, or an acyl group. Among R ^{1 to} R ⁶ of each compound, those in which all are alkyl groups or those in which any one is an alkyl group and the remainder is an acyl group are preferable.

  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-butyl peroxide Oxybenzoate, tert-butyl peroxyisopropyl carbonate, diace Peroxide, lauroyl peroxide, may be mentioned tert- butyl cumyl peroxide and the like. Of these, dicumyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl-2 are preferable in terms of odor, colorability, and scorch stability. , 5-Di- (tert-butylperoxy) hexyne-3 is preferred.

The decomposition temperature of the organic peroxide is preferably from 80 to 195 ° C, particularly preferably from 125 to 180 ° C.
In the present invention, the decomposition temperature of an organic peroxide means a temperature at which a decomposition reaction occurs in two or more compounds at a certain temperature or temperature range when an organic peroxide having a single composition is heated. means. 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>
In the present invention, the inorganic filler is not particularly limited as long as the inorganic filler has a site capable of chemically bonding with a reactive site such as a silanol group of the silane coupling agent and a hydrogen bond or a covalent bond, or an intermolecular bond. Can be used. Examples of the site that can be chemically bonded to the reaction site of the silane coupling agent in this inorganic filler include OH groups (hydroxy groups, water molecules containing water or water of crystal water, OH groups such as carboxy groups), amino groups, and SH groups. It is done.

  The inorganic filler is not particularly limited. For example, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide (boehmite, etc.), aluminum nitride, Examples thereof include metal hydrates such as aluminum borate whisker, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, hydrotalcite, talc and the like having a hydroxyl group or crystal water. Boron nitride, silica (crystalline silica, amorphous silica, etc.), carbon, clay, zinc oxide, tin oxide, titanium oxide, molybdenum oxide, antimony trioxide, silicone compound, quartz, zinc borate, white carbon, Examples include zinc borate, zinc hydroxystannate, and zinc stannate.

As the inorganic filler, a surface-treated inorganic filler surface-treated with a silane coupling agent or the like can be used. For example, Kisuma 5L, Kisuma 5P (both trade names, magnesium hydroxide, manufactured by Kyowa Chemical Industry Co., Ltd., etc.) and the like are exemplified as the silane coupling agent surface treatment inorganic filler. The surface treatment amount of the inorganic filler by the silane coupling agent is not particularly limited, but is, for example, 3% by mass or less.
Of these inorganic fillers, silica, boehmite, clay, talc, aluminum hydroxide, magnesium hydroxide, calcium carbonate, or combinations thereof are preferred.
An inorganic filler may be used individually by 1 type, and may use 2 or more types together.

  When the inorganic filler is a powder, the average particle size of the inorganic filler is preferably 0.2 to 10 μm, more preferably 0.3 to 8 μm, further preferably 0.4 to 5 μm, particularly 0.4 to 3 μm. preferable. When the average particle size is within the above range, the retention effect of the silane coupling agent is high and the heat resistance is excellent. Further, the inorganic filler hardly aggregates when mixed with the silane coupling agent, and the appearance is excellent. The average particle size is obtained by an optical particle size measuring device such as a laser diffraction / scattering type particle size distribution measuring device in which an inorganic filler is dispersed with alcohol or water.

<Silane coupling agent>
The silane coupling agent used in the present invention can chemically bond a grafting reaction site (group or atom) capable of grafting to the base resin in the presence of radicals generated by the decomposition of an organic peroxide and an inorganic filler. It is sufficient to have at least a reactive site capable of reacting with a site and capable of silanol condensation (including a site generated by hydrolysis, such as a silyl ester group). As such a silane coupling agent, the silane coupling agent conventionally used for the silane crosslinking method is mentioned.

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

In general formula (1), R _a11 is a group containing an ethylenically unsaturated group, and 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 is a grafting reaction site and is preferably a group containing an ethylenically unsaturated group. Examples of the group containing an ethylenically unsaturated group include a vinyl group, a (meth) acryloyloxyalkylene group, and a p-styryl group. Among these, a vinyl group is preferable.

R _b11 represents an aliphatic hydrocarbon group, a hydrogen atom, or Y ¹³ described later. Examples of the aliphatic hydrocarbon group include monovalent aliphatic hydrocarbon groups having 1 to 8 carbon atoms excluding the aliphatic unsaturated hydrocarbon group. R _b11 is preferably Y ¹³ described later.

Y ¹¹ , Y ¹² and Y ^{13 each} represent a reactive site capable of silanol condensation (an organic group that can be hydrolyzed). For example, a C1-C6 alkoxy group, a C6-C10 aryloxy group, and a C1-C4 acyloxy group are mentioned, An alkoxy group is preferable. Specific examples of the hydrolyzable organic group include methoxy, ethoxy, butoxy, acyloxy and the like. Among these, methoxy or ethoxy is more preferable from the viewpoint of the reactivity of the silane coupling agent.

The silane coupling agent is preferably a silane coupling agent having a high hydrolysis rate, more preferably a silane cup in which R _b11 is Y ¹³ and Y ¹¹ , Y ¹² and Y ¹³ are the same. A ring agent or a silane coupling agent in which at least one of Y ¹¹ , Y ¹² and Y ¹³ is a methoxy group.

Specific examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltributoxysilane, vinyldimethoxyethoxysilane, vinyldimethoxybutoxysilane, vinyldiethoxybutoxysilane, allyltrimethoxysilane, allyltrimethoxysilane. Examples thereof include vinyl silanes such as ethoxysilane and vinyltriacetoxysilane, and (meth) acryloxysilanes such as methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, and methacryloxypropylmethyldimethoxysilane.
Among the silane coupling agents, a silane coupling agent having a vinyl group and an alkoxy group at the terminal is more preferable, and vinyltrimethoxysilane or vinyltriethoxysilane is particularly preferable.
A silane coupling agent may be used individually by 1 type, and may use 2 or more types together. Further, it may be used as it is or diluted with a solvent or the like.

<Silanol condensation catalyst>
The silanol condensation catalyst has a function of causing a silane coupling agent grafted to a polyolefin resin or rubber to undergo a condensation reaction in the presence of moisture. Based on the action of this silanol condensation catalyst, the resin components are cross-linked through a silane coupling agent. As a result, a silane cross-linked resin molded article having excellent heat resistance is obtained.

It does not specifically limit as a silanol condensation catalyst, For example, an organotin compound, a metal soap, a platinum compound etc. are mentioned. Common silanol condensation catalysts include, for example, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctate, dibutyltin diacetate, zinc stearate, lead stearate, barium stearate, calcium stearate, sodium stearate, lead naphthenate, Lead sulfate, zinc sulfate, organic platinum compounds and the like are used.
When the silane graft resin component and the silane crosslinking catalyst master batch are mixed, the silanol condensation catalyst is added in an amount of 0.02 to 0.5 parts by mass, preferably 0. It is 05-0.4 mass part, More preferably, it is 0.08-0.3 mass part. By adjusting to this blending amount, generation of gel spots can be suppressed at the time of molding, and cross-linking proceeds sufficiently and the strength and heat resistance are excellent.

<Carrier resin>
The silanol condensation catalyst is used by mixing with a resin if desired. Such a resin (also referred to as carrier resin) is not particularly limited, and each resin or rubber described in the base resin can be used.

<Other additives>
In the present invention, various additives commonly used in electric wires, electric cables, electric cords, automobile members, OA equipment, building members, sundries, sheets, foams, tubes, and pipes are intended. You may mix | blend suitably in the range which does not impair an effect. Examples of such additives include crosslinking aids, antioxidants, lubricants, metal deactivators, flame retardant (auxiliary) agents and other resins.
A crosslinking aid refers to a compound that forms a partially crosslinked structure with a resin component in the presence of an organic peroxide. For example, a polyfunctional compound etc. are mentioned.
Although it does not specifically limit as antioxidant, For example, amine antioxidant, phenol antioxidant, sulfur antioxidant, etc. are mentioned.
Examples of the lubricant include hydrocarbons, siloxanes, fatty acids, fatty acid amides, esters, alcohols, metal soaps, and the like.

Next, the production method of the present invention will be specifically described.
The manufacturing method of the silane crosslinked resin molding of this invention has the following process (a)-process (c).
The silane master batch of the present invention is produced by the following step (a), and the master batch mixture of the present invention is produced by the following step (a) and step (b).

Step (a): 0.1 to 20 parts by mass of an acrylic polymer, 0.003 to 0.3 parts by mass of an organic peroxide, and 0.1 to 0.3 parts by mass of an inorganic filler with respect to 100 parts by mass of the polyolefin base resin or rubber. 5 to 400 parts by mass, and over 2 parts by mass of the silane coupling agent and 15.0 parts by mass or less are melt-mixed (also referred to as melt-kneading or kneading) at a temperature equal to or higher than the decomposition temperature of the organic peroxide, Step of preparing silane masterbatch Step (b): Step of molding after mixing silane masterbatch obtained in step (a) and silanol condensation catalyst Step (c): Molded body obtained in step (b) Step of bringing water into contact with water and crosslinking Here, mixing means obtaining a uniform mixture.

  In the step (a), the base resin component is not particularly limited as long as it contains a polyolefin resin or rubber, and a styrene thermoplastic elastomer, mineral oil, and the like can be used together.

  In the step (a), the base resin is melted and mixed with the acrylic polymer, the inorganic filler, and the silane coupling agent in the presence of the organic peroxide at a temperature equal to or higher than the decomposition temperature of the organic peroxide. By the step (a), a silane master batch (also referred to as silane MB) is obtained as a molten mixture.

  In the step (a), the blending amount of the acrylic polymer is 0.1 to 20 parts by mass, preferably 0.5 to 10 parts by mass, and 1 to 6 parts by mass with respect to 100 parts by mass of the base resin. More preferred. If the blending amount of the acrylic polymer is less than 0.1 parts by mass, a smear may occur during extrusion molding. On the other hand, when it exceeds 20 parts by mass, physical properties such as heat resistance and mechanical strength may be deteriorated. Also, it may bleed out.

  In the step (a), the compounding amount of the organic peroxide is 0.003 to 0.3 parts by mass, preferably 0.005 to 0.3 parts by mass with respect to 100 parts by mass of the base resin. 005 to 0.1 parts by mass is more preferable. When the amount of the organic peroxide is less than 0.003 parts by mass, the graft reaction does not proceed, the unreacted silane coupling agents are condensed with each other or the unreacted silane coupling agent is volatilized, and the heat resistance is sufficient. You may not be able to get to. On the other hand, if it exceeds 0.3 parts by mass, many of the resin components may be directly cross-linked by side reactions to form bunches, resulting in poor appearance. Moreover, the silane masterbatch etc. which were excellent in extrusion property may not be obtained. That is, by setting the blending amount of the organic peroxide within this range, the graft reaction can be carried out within an appropriate range, and a silane master excellent in extrudability without causing gel-like lumps (agglomerates). Batch etc. can be obtained.

  The compounding quantity of an inorganic filler is 0.5-400 mass parts with respect to 100 mass parts of base resins, and 30-280 mass parts is preferable. When the blending amount of the inorganic filler is less than 0.5 parts by mass, the graft reaction of the silane coupling agent becomes nonuniform, and it may not be possible to impart excellent heat resistance to the silane crosslinked resin molded product. In addition, the graft reaction of the silane coupling agent becomes non-uniform, and the appearance of the silane cross-linked resin molded product may deteriorate. On the other hand, when it exceeds 400 parts by mass, the load during molding or melt mixing becomes very large, and secondary molding may be difficult. Moreover, heat resistance and an external appearance may fall.

The compounding quantity of a silane coupling agent exceeds 2.0 mass parts with respect to 100 mass parts of base resins, and is 15.0 mass parts or less. When the compounding amount of the silane coupling agent is 2.0 parts by mass or less, the crosslinking reaction does not proceed sufficiently and the excellent heat resistance may not be exhibited. In addition, when molding with a silanol condensation catalyst, poor appearance and irregularities may occur, and many irregularities may occur when the extruder is stopped. On the other hand, if it exceeds 15.0 parts by mass, the silane coupling agent cannot be completely adsorbed on the surface of the inorganic filler, and the silane coupling agent volatilizes during melt mixing, which is not economical. Moreover, the silane coupling agent which does not adsorb | suck condenses, and there exists a possibility that a bridge | crosslinking gel and a burning may arise in a molded object, and an external appearance may deteriorate.
From the above viewpoint, the blending amount of the silane coupling agent is preferably 3 to 12.0 parts by mass and more preferably 4 to 12.0 parts by mass with respect to 100 parts by mass of the base resin.

  The blending amount of the silanol condensation catalyst is not particularly limited, and is preferably 0.0001 to 0.5 parts by mass, more preferably 0.001 to 0.2 parts by mass with respect to 100 parts by mass of the base resin. When the blending amount of the silanol condensation catalyst is within the above range, the crosslinking reaction by the condensation reaction of the silane coupling agent tends to proceed almost uniformly, and the heat resistance, appearance and physical properties of the silane crosslinked resin molded article are excellent, and the productivity is also high. improves. That is, if the amount of the silanol condensation catalyst is too small, crosslinking due to the condensation reaction of the silane coupling agent is difficult to proceed, and the heat resistance of the silane crosslinked resin molded product is not improved easily, resulting in decreased productivity or crosslinking. May be non-uniform. On the other hand, if the amount is too large, the silanol condensation reaction proceeds very fast, causing partial gelation, which may deteriorate the appearance. Moreover, the physical properties of the silane cross-linked resin molded product (resin) may deteriorate.

In the present invention, “melting and mixing an acrylic polymer, an organic peroxide, an inorganic filler and a silane coupling agent with respect to a polyolefin-based base resin or rubber” specifies the mixing order when melt-mixing. It means that they may be mixed in any order. The mixing order in the step (a) is not particularly limited. In the present invention, the inorganic filler is preferably used by mixing with a silane coupling agent. That is, in the present invention, it is preferable to (melt) mix the above-mentioned components by the following steps (a-1) and (a-2).
Step (a-1): Step of preparing a mixture by mixing at least an inorganic filler and a silane coupling agent Step (a-2): All or one of the base resin and the mixture obtained in Step (a-1) Melting and mixing a part and an acrylic polymer at a temperature equal to or higher than the decomposition temperature of the organic peroxide in the presence of the organic peroxide.

The step (a-2) includes “an aspect in which the total amount (100 parts by mass) of the base resin is blended” and “an aspect in which a part of the base resin is blended”. In the step (a-2), when a part of the base resin is blended, the remainder of the base resin is preferably blended in the step (b).
When a part of the base resin is blended in the step (a-2), 100 parts by mass of the base resin in the step (a) and the step (b) is mixed in the step (a-2) and the step (b). This is the total amount of base resin to be processed.
Here, when the remainder of the base resin is blended in the step (b), the base resin is blended in the step (a-2), preferably 55 to 99% by mass, more preferably 60 to 95% by mass, In a process (b), Preferably it is 1-45 mass%, More preferably, 5-40 mass% is mix | blended.

In the present invention, the silane coupling agent is preferably premixed with an inorganic filler as described above (step (a-1)).
A method of mixing the inorganic filler and the silane coupling agent is not particularly limited, and examples thereof include a mixing method such as a wet process and a dry process. Specifically, a wet treatment in which an inorganic filler is dispersed in a solvent such as alcohol or water, a wet treatment in which a silane coupling agent is added, an untreated inorganic filler, or stearic acid, oleic acid, phosphate ester or Examples thereof include a dry treatment in which a silane coupling agent is heated or non-heated and mixed in an inorganic filler whose surface is treated with a silane coupling agent, and both. In the present invention, dry processing is preferred in which a silane coupling agent is added to an inorganic filler, preferably a dried inorganic filler, with heating or non-heating and mixed.
The silane coupling agent premixed in this manner exists so as to surround the surface of the inorganic filler, and a part or all of the silane coupling agent is adsorbed or bonded to the inorganic filler. Thereby, volatilization of the silane coupling agent can be reduced during subsequent melt mixing. Moreover, it is possible to prevent the silane coupling agent that is not adsorbed or bonded to the inorganic filler from condensing and becoming difficult to melt and mix. Furthermore, a desired shape can be obtained during extrusion molding.

As such a mixing method, preferably, the inorganic filler and the silane coupling agent are mixed in a dry or wet manner for several minutes to several hours at a temperature lower than the decomposition temperature of the organic peroxide, preferably at room temperature (25 ° C.). A method of melting and mixing the mixture and the resin in the presence of an organic peroxide after (dispersing) is mentioned. This mixing is preferably performed with a mixer-type mixer such as a Banbury mixer or a kneader. If it does in this way, the excessive crosslinking reaction of resin components can be prevented, and the external appearance will be excellent.
In this mixing method, a resin may be present as long as a temperature lower than the decomposition temperature is maintained. In this case, it is preferable that the metal oxide and the silane coupling agent are mixed with the resin at the above temperature (step (a-1)) and then melt mixed.

The method for mixing the organic peroxide is not particularly limited, and it may be present when the mixture and the base resin are melt-mixed. The organic peroxide, for example, may be mixed simultaneously with the inorganic filler or the like, or may be mixed in any of the mixing stages of the inorganic filler and the silane coupling agent, to form a mixture of the inorganic filler and the silane coupling agent. It may be mixed. For example, the organic peroxide may be mixed with the inorganic filler after being mixed with the silane coupling agent, or may be separately mixed with the inorganic filler separately from the silane coupling agent. Depending on production conditions, only the silane coupling agent may be mixed with the inorganic filler, and then the organic peroxide may be mixed.
The organic peroxide may be mixed with other components or may be a simple substance.

  In the mixing method of the inorganic filler and the silane coupling agent, in the wet mixing, since the bonding force between the silane coupling agent and the inorganic filler becomes strong, volatilization of the silane coupling agent can be effectively suppressed. The condensation reaction may be difficult to proceed. On the other hand, in dry mixing, the silane coupling agent tends to volatilize, but since the bonding strength between the inorganic filler and the silane coupling agent becomes relatively weak, the silanol condensation reaction easily proceeds efficiently.

  The method for mixing the acrylic polymer is not particularly limited, and may be present when the mixture and the base resin are melt-mixed.

Next, in the production method of the present invention, all or a part of the obtained mixture and the base resin, and the remaining components not mixed in step (a-1) are organically added in the presence of an organic peroxide. While being heated to a temperature equal to or higher than the decomposition temperature of the peroxide, melt mixing is performed (step (a-2)).
In the melt mixing in the step (a-2), the mixing order of the components is not particularly limited, and may be mixed in any order. For example, the above components may be melted and mixed at one time, or all or a part of the base resin may be melted and then the mixture or the like may be mixed.

In the step (a-2), the temperature at which the above components are melt-mixed is equal to or higher than the decomposition temperature of the organic peroxide, preferably the decomposition temperature of the organic peroxide + (25 to 110) ° C., more preferably 150-230 ° C. This decomposition temperature is preferably set after the resin component has melted. If it is the said mixing temperature, the said component will melt | dissolve and an organic peroxide will decompose | disassemble and act and a required silane grafting reaction will fully advance in a process (a-2). Other conditions such as the mixing time can be set as appropriate.
The mixing method is not particularly limited as long as it is a method usually used for rubber, plastic and the like. The mixing device is appropriately selected according to, for example, the blending amount of the inorganic filler. As a mixing apparatus, a single screw extruder, a twin screw extruder, a roll, a Banbury mixer, or various kneaders are used. In terms of the dispersibility of the resin component and the stability of the cross-linking reaction, a closed mixer is preferable among Banbury mixers and various kneaders.
In general, when such an inorganic filler is mixed in an amount exceeding 100 parts by mass with respect to 100 parts by mass of the base resin, it is melt-mixed with a closed mixer such as a continuous mixer, a pressure kneader, or a Banbury mixer. It is good.
The mixing method of the base resin is not particularly limited. For example, the base resin may be mixed as it is, or each component, for example, a resin component such as polyolefin resin, oil or plasticizer may be mixed separately.

In the present invention, when the above-described components are melt-mixed at a time, the melt-mixing conditions are not particularly limited, but the conditions of the step (a-2) can be adopted.
In this case, part or all of the silane coupling agent is adsorbed or bonded to the inorganic filler during melt mixing.

  In the step (a), particularly in the step (a-2), it is preferable to melt and mix the above-mentioned components without substantially mixing the silanol condensation catalyst. Thereby, the condensation reaction of a silane coupling agent can be suppressed, it is easy to melt and mix, and a desired shape can be obtained during extrusion molding. Here, “substantially not mixed” does not exclude the unavoidably existing silanol condensation catalyst, and is present to such an extent that the above-mentioned problem due to silanol condensation of the silane coupling agent does not occur. Means good. For example, in the step (a-2), the silanol condensation catalyst may be present as long as it is 0.01 part by mass or less with respect to 100 parts by mass of the base resin.

In the step (a), other resins that can be used in addition to the above components and the blending amounts of the above additives are appropriately set within a range that does not impair the object of the present invention.
In step (a), the above additives, particularly antioxidants and metal deactivators, may be mixed in any step or component, but the silane coupling agent mixed in the inorganic filler is grafted to the resin. It is good to mix with carrier resin at the point which does not inhibit reaction.
In the step (a), particularly in the step (a-2), it is preferable that the crosslinking assistant is not substantially mixed. If the cross-linking aid is not substantially mixed, the cross-linking reaction between the resin components hardly occurs due to the organic peroxide during the melt mixing, and the appearance is excellent. Further, the graft reaction of the silane coupling agent to the resin hardly occurs, and the heat resistance is excellent. Here, the fact that it is not substantially mixed does not exclude the unavoidable crosslinking aid, and means that it may be present to such an extent that the above-mentioned problems do not occur.

  Thus, a process (a) is performed and the silane masterbatch (it is also called silane MB) used for manufacture of a masterbatch mixture is prepared. This silane MB contains a silane crosslinkable resin in which a silane coupling agent is grafted to the base resin to such an extent that it can be molded by the step (b) described later. Moreover, it is preferable that each component is disperse | distributed uniformly in a silane masterbatch.

In the production method of the present invention, next, the step (b) of forming after mixing the silane MB obtained in the step (a) and the silanol condensation catalyst is performed.
In the step (b), when a part of the base resin is melt-mixed in the step (a-2), the remainder of the base resin and the silanol condensation catalyst are melt-mixed, and a catalyst master batch (also referred to as catalyst MB) is prepared. It is preferable to prepare and use. In addition to the remainder of the base resin, other resins or the like may be added as necessary.

The mixing ratio of the remainder of the base resin as the carrier resin and the silanol condensation catalyst is not particularly limited, but is preferably set so as to satisfy the blending amount in the step (a).
The mixing may be a method capable of uniformly mixing, and includes mixing (melting mixing) performed under melting of the base resin. The melt mixing can be performed in the same manner as the melt mixing in the step (a-2). For example, the mixing temperature is preferably 120 to 170 ° C., for example. Other conditions such as the mixing time can be set as appropriate.
The catalyst MB thus prepared is a mixture of a silanol condensation catalyst, a carrier resin, and a filler that is optionally added.

On the other hand, when all of the base resin is melt-mixed in the step (a-2), in the step (b), a silanol condensation catalyst itself or a mixture of another resin and a silanol condensation catalyst is used. The mixing method of the other resin and the silanol condensation catalyst is the same as that of the catalyst MB.
The blending amount of the other resin is preferably 1 to 60 masses with respect to 100 mass parts of the base resin in that the graft reaction can be promoted in the step (a-2), and in addition, no blisters are generated during molding. Parts, more preferably 2 to 50 parts by mass, still more preferably 2 to 40 parts by mass.

In the production method of the present invention, silane MB and silanol condensation catalyst (silanol condensation catalyst itself, or catalyst MB, or a mixture of silanol condensation catalyst and other resin) are mixed.
The mixing method may be any mixing method as long as a uniform mixture can be obtained as described above. For example, the mixing is basically the same as the melt mixing in the step (a-2). Some resin components, such as elastomers, whose melting points cannot be measured by DSC or the like, are melt-mixed at least at a temperature at which the base resin melts. The melting temperature is appropriately selected according to the melting temperature of the base resin or the carrier resin, and is preferably 80 to 250 ° C., more preferably 100 to 240 ° C., for example. Other conditions such as the mixing time can be set as appropriate.
In step (b), in order to avoid a silanol condensation reaction, it is preferable that the silane MB and the silanol condensation catalyst are not mixed and kept at a high temperature for a long time.

  In the step (b), the silane MB and the silanol condensation catalyst may be mixed, and when the silane MB and the catalyst MB are used, they are preferably melt mixed.

  In the present invention, the silane MB and the silanol condensation catalyst can be dry blended before being melt mixed. The method and conditions for dry blending are not particularly limited, and examples thereof include dry mixing in step (a-1) and the conditions thereof. By this dry blending, a master batch mixture containing silane MB and a silanol condensation catalyst is obtained.

  In the step (b), an inorganic filler may be used. In this case, although the compounding quantity of an inorganic filler is not specifically limited, 350 mass parts or less are preferable with respect to 100 mass parts of carrier resins. This is because if the amount of the inorganic filler is too large, the silanol condensation catalyst is difficult to disperse and cross-linking is difficult to proceed. On the other hand, when there are too few compounding quantities of an inorganic filler, the crosslinking degree of a molded object falls and sufficient heat resistance may not be obtained.

  In the present invention, the mixing of the step (a) and the step (b) can be performed simultaneously or continuously.

In step (b), the mixture thus obtained is molded.
The molding step is not limited as long as the mixture can be molded, and a molding method and molding conditions are appropriately selected according to the form of the heat-resistant product of the present invention. Examples of the molding method include extrusion molding using an extruder.

In the step (b), the forming step can be performed simultaneously with or continuously with the mixing step. That is, as an embodiment of the melt mixing in the mixing step, there is an embodiment in which the forming raw material is melt-mixed at the time of melt-molding, for example, at the time of extrusion molding or just before that. For example, pellets such as dry blends may be mixed together at room temperature or high temperature and introduced into a molding machine (melt mixing), or mixed and then melt mixed, pelletized again, and then introduced into the molding machine. Also good. More specifically, a series of steps in which a mixture (molding material) of silane MB and a silanol condensation catalyst is melt-mixed in a coating apparatus, and then extrusion coated on the outer peripheral surface of a conductor or the like to be molded into a desired shape. Can be adopted.
Thus, a silane masterbatch and a silanol condensation catalyst are dry blended to prepare a masterbatch mixture, and a molded body of the silane crosslinkable resin composition is obtained by molding the masterbatch mixture into a molding machine. .

Here, the molten mixture of the master batch mixture contains silane crosslinkable resins having different crosslinking methods. In this silane crosslinkable resin, the reaction site of the silane coupling agent may be bonded or adsorbed to the inorganic filler, but is not silanol condensed as described later. Therefore, in the silane crosslinkable resin, the silane coupling agent bonded or adsorbed to the inorganic filler is grafted to the base resin, and the grafted crosslinkable resin and the silane coupling agent not bonded to or adsorbed to the inorganic filler are grafted to the base resin. And at least a crosslinkable resin. The silane crosslinkable resin may have a silane coupling agent to which an inorganic filler is bonded or adsorbed and a silane coupling agent to which an inorganic filler is not bonded or adsorbed. Furthermore, a silane coupling agent and an unreacted resin component may be included.
As described above, the silane crosslinkable resin is an uncrosslinked product in which the silane coupling agent is not silanol condensed. In practice, when melt-mixed in step (b), partial cross-linking (partial cross-linking) is inevitable, but the obtained silane cross-linkable resin composition retains at least the moldability during molding. And
The molded product obtained in the step (b) is partially crosslinked as in the case of the above mixture, but is in a partially crosslinked state that retains the moldability that can be molded in the step (b). Therefore, the silane cross-linked resin molded product of the present invention is formed into a cross-linked or finally cross-linked molded product by performing the step (c).

In the manufacturing method of the silane crosslinked resin molding of this invention, the process (c) which contacts the molded object obtained at the process (b) with water is performed. Thereby, the reaction site of the silane coupling agent is hydrolyzed to become silanol, and the hydroxyl groups of silanol are condensed with each other by the silanol condensation catalyst present in the molded article, thereby causing a crosslinking reaction. Thus, a silane cross-linked resin molded product in which the silane coupling agent is cross-linked by silanol condensation can be obtained.
The process itself of this process (c) can be performed by a normal method. Condensation between 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 with water.
In order to promote this crosslinking reaction, the molded body can be brought into contact with moisture. 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 silane crosslinked resin molded object of this invention is implemented, and a silane crosslinked resin molded object is manufactured. This silane cross-linked resin molded product contains a cross-linked resin obtained by condensing a (silane cross-linkable) resin via a silanol bond (siloxane bond). One form of this silane crosslinked resin molding contains a silane crosslinked resin and an inorganic filler. Here, the inorganic filler may be bonded to the silane coupling agent of the silane cross-linked resin. Therefore, it includes an embodiment in which the base resin is crosslinked with an inorganic filler via a silanol bond. Specifically, the silane cross-linked resin includes a cross-linked resin in which a plurality of cross-linked resins are bonded or adsorbed to an inorganic filler by a silane coupling agent and bonded (cross-linked) via the inorganic filler and the silane coupling agent, The reaction site of the silane coupling agent grafted on the crosslinkable resin hydrolyzes and undergoes silanol condensation reaction with each other, thereby containing at least a crosslinked resin crosslinked via the silane coupling agent. Moreover, as for the silane crosslinking resin, a bond (crosslinking) via an inorganic filler and a silane coupling agent and a crosslinking via a silane coupling agent may be mixed. Furthermore, the silane coupling agent and the unreacted resin component and / or the silane crosslinkable resin which is not bridge | crosslinked may be included.

The manufacturing method of the present invention can be expressed as follows.
It is a manufacturing method of the silane crosslinked resin molding which has the following process (A), a process (B), and a process (C), Comprising: A process (A) has the following process (A1)-process (A4). Body manufacturing method.
Step (A): 0.1 to 20 parts by mass of an acrylic polymer, 0.003 to 0.3 parts by mass of an organic peroxide and 0.5 inorganic filler with respect to 100 parts by mass of a polyolefin base resin or rubber Process step (B) in which a mixture is obtained by mixing ~ 400 parts by mass, more than 2 parts by mass of the silane coupling agent and 15.0 parts by mass or less, and a silanol condensation catalyst. The mixture obtained in step (A) Step (C) for obtaining a molded body by molding: Step (A1) for obtaining a silane-crosslinked resin molded body by contacting the molded body obtained in step (B) with water: At least an inorganic filler and a silane coupling agent Step (A2) of mixing: The step of melting and mixing the mixture obtained in step (A1) and the whole or part of the base resin at a temperature equal to or higher than the decomposition temperature of the organic peroxide in the presence of the organic peroxide. Step (A3): Cyrano Step (A4) of mixing a condensation catalyst and a resin different from the base resin as the carrier resin or the remainder of the base resin: the molten mixture obtained in the step (A2) and the mixture obtained in the step (A3) Step of mixing In the above method, the step (A) corresponds to the mixing of the step (a) and the step (b), the step (B) corresponds to the molding step of the step (b), and the step (C ) Corresponds to step (c) above. The step (A1) is the step (a-1), the step (A2) is the step (a-2), the steps (A3) and (A4) are mixed by the step (b). Each corresponds.

The details of the reaction mechanism in the production method of the present invention are not yet clear, but are considered as follows.
That is, by using (mixing) an inorganic filler and a silane coupling agent before and / or during kneading with the base resin, the silane coupling agent binds to the inorganic filler with a group capable of chemically bonding, It is bonded to the uncrosslinked portion of the resin component with a group capable of graft reaction existing at the other end and held. Alternatively, the silane coupling agent is a group that can be chemically bonded to a hole or surface of the inorganic filler without bonding to the inorganic filler, and can be grafted to the resin component without bonding to the inorganic filler. Bonded with the uncrosslinked portion and retained. Thus, a silane coupling agent that binds to an inorganic filler with a strong bond (for example, a chemical bond with a hydroxyl group on the surface of the inorganic filler may be considered) and a silane coupling agent that binds to a weak bond (for example, The reason can be, for example, an interaction by hydrogen bond, an interaction between ions, partial charges or dipoles, an action by adsorption, etc.). In this state, by adding an organic peroxide and kneading with the base resin, the silane coupling agent is hardly volatilized as described above, and condensation between the silane coupling agents is suppressed, and the inorganic filler and A silane crosslinkable resin is formed by graft reaction of silane coupling agents having different bonds to the resin component.

Even by the kneading described above, among the silane coupling agents, the silane coupling agent having a strong bond with the inorganic filler retains the bond with the inorganic filler, and the crosslinkable group that can undergo a graft reaction is present in the crosslinkable portion of the resin component. Graft reaction. In particular, when a plurality of silane coupling agents are bonded to the surface of one inorganic filler particle through a strong bond, a plurality of resin components are bonded through the inorganic filler particle. By these reactions or bonds, the crosslinked network via the inorganic filler is expanded. That is, a silane crosslinkable resin formed by graft reaction of the silane coupling agent bonded to the inorganic filler onto the resin component is formed.
The silane coupling agent having a strong bond with the inorganic filler hardly causes a condensation reaction in the presence of water by the silanol condensation catalyst, and the bond with the inorganic filler is maintained. The reason why the silanol condensation reaction hardly occurs is considered to be that the binding energy between the inorganic filler and the silane coupling agent is very high and the condensation reaction does not occur even under the silanol condensation catalyst. Thus, the resin component and the inorganic filler are bonded, and the resin component is cross-linked through the silane coupling agent. As a result, the adhesiveness between the resin component and the inorganic filler is strengthened, and a molded article having good mechanical strength and wear resistance and hardly scratched is obtained. In particular, a plurality of silane coupling agents can be bonded to the surface of one inorganic filler particle, and high mechanical strength can be obtained. Thus, the silane coupling agent bonded with a strong bond to the inorganic filler is considered to contribute to the development or improvement of scratch resistance, mechanical properties, and in some cases, wear resistance.

  On the other hand, among the silane coupling agents, the silane coupling agent having a weak bond with the inorganic filler is separated from the surface of the inorganic filler by the kneading described above, and is a group capable of undergoing a graft reaction, which is a crosslinking group of the silane coupling agent. However, it reacts with the radicals of the resin component generated by the extraction of hydrogen radicals by radicals generated by the decomposition of the organic peroxide to cause a graft reaction. That is, a silane crosslinkable resin is formed by graft reaction of the silane coupling agent released from the inorganic filler to the resin component. The silane coupling agent in the graft portion thus produced is then mixed with a silanol condensation catalyst and brought into contact with moisture to cause a condensation reaction (crosslinking reaction). The heat resistance of the silane cross-linked resin molded product obtained by this cross-linking reaction is increased. Thus, it is considered that the silane coupling agent bonded to the inorganic filler with a weak bond contributes to an improvement in the degree of crosslinking, that is, an improvement in heat resistance.

  Furthermore, when the silane coupling agent is previously mixed with the inorganic filler by the production method of the present invention, the appearance is excellent because the condensation between the silane coupling agents is suppressed as described above.

In the production method of the present invention, when a polyolefin resin or rubber is used as a base resin and an acrylic polymer is used in a specific ratio, it is possible to prevent scumming during extrusion molding. An excellent appearance can be imparted without impairing heat resistance. Although it is not yet certain about the details that such excellent characteristics can be imparted to the silane cross-linked resin molded article, it is considered as follows.
That is, when the above-mentioned polyolefin base resin or rubber and an acrylic polymer are used in a specific ratio, the graft reaction is not inhibited and an excessive graft reaction is unlikely to occur at the time of preparing the silane masterbatch. Furthermore, the condensation reaction between silanol groups hardly occurs. This is presumably because the acrylic polymer does not function as a metal catalyst. Thereby, generation | occurrence | production of a gel but is reduced and the molded object excellent in the external appearance can be obtained.
Polyolefin base resins or rubbers and acrylic polymers are highly compatible. Particularly, high molecular weight acrylic copolymers are easily entangled with the base resin, and the melt elasticity of the molten mixture is increased. Therefore, the acrylic polymer increases dispersibility of other components such as a silane coupling agent and an inorganic filler. Thereby, bridge | crosslinking etc. advance uniformly and it can suppress the fall of physical properties, such as heat resistance, of a molded object.
Furthermore, since part of the acrylic polymer is exposed on the surface of the molten mixture (or silane crosslinkable resin molded body), the adhesiveness of the molten mixture can be reduced. Thereby, the friction between the die of the extruder and the molten mixture is reduced, and the generation of resin residue at the die outlet can be suppressed.
In the present invention, when these are exhibited in a well-balanced manner, the occurrence of scouring at the time of molding can be reduced, and excellent appearance and heat resistance can be imparted to the silane crosslinked resin molded product.

The manufacturing method of the present invention can be applied to the manufacture of products (such as semi-finished products, parts, and members) that require heat resistance, product components such as rubber materials, or members thereof. Therefore, the heat-resistant product of the present invention is a product as described above having heat resistance. At this time, the heat-resistant product may be a product including a silane cross-linked resin molded body, or may be a product including only a silane cross-linked resin molded body.
Examples of the heat-resistant product of the present invention include not only a heat-resistant electric wire or cable covering material, but also a rubber mold material that requires heat resistance (for example, an automotive glass run channel, a weather strip, a rubber hose, a wiper blade rubber, and a vibration-proof rubber. ), Etc., a polyolefin material product that has been conventionally subjected to crosslinking by electron beam irradiation or a chemical vulcanization process, an alternative product of an EP rubber product, and the like.

The manufacturing method of the present invention can be suitably applied to the manufacture of electric wires and optical fiber cables among the above products, and can form these coating materials (insulators or sheaths).
When the heat-resistant product of the present invention is an electric wire or a cable, preferably, the silane crosslinkable resin is prepared while melt-kneading the molding material in an extruder (extrusion coating apparatus) to prepare a silane crosslinkable resin composition. It can be produced by extruding the composition on the outer periphery of a conductor or the like and covering the conductor or the like. Such heat-resistant products can be used around a conductor by using a general-purpose extrusion coating device without using special equipment such as electron beam crosslinking equipment, even if a large amount of inorganic filler is added. Alternatively, it can be formed by extrusion-coating around a conductor in which tensile strength fibers are added or twisted together. For example, a single wire or stranded wire such as annealed copper, copper alloy, or aluminum can be used as the conductor. In addition to the bare wire, a conductor plated with tin or an enameled insulating layer can be used as the conductor. The thickness of the insulating layer (the coating layer made of the silane cross-linked resin molded body of the present invention) formed around the conductor is not particularly limited, but is usually about 0.15 to 5 mm.
When extruding an electric wire, the temperature of the extrusion molding machine depends on various conditions such as the type of resin and the take-up speed of the conductor, etc., but 120 to 150 ° C. at the cylinder portion and about 160 to 180 ° C. at the cross head portion. It is preferable to make it about.

EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.
In Tables 1 and 2, the numerical values related to the blending amounts in each example represent parts by mass unless otherwise specified.

  In Examples 1 to 14 and Comparative Examples 1 to 8, the following components were used and the respective specifications were set to the conditions shown in Tables 1 and 2, and the evaluation results described later in Tables 1 and 2 are shown. Also shown.

As each component shown in Table 1 and Table 2, the following were used.
<Base resin>
(Polyolefin resin or rubber)
Ethylene-α-olefin copolymer rubber: Nodel 3720P (trade name, manufactured by Dow, ethylene-propylene-ethylidene norbornene rubber, ethylene component content 70 mass%, diene component content 0.5 mass%)
Ethylene-α-olefin copolymer rubber: EPT0045 (trade name, manufactured by Mitsui Chemicals, ethylene-propylene rubber, ethylene component content 51 mass%, diene component content 0 mass%)
Resin of ethylene-α-olefin copolymer: Sumikasen CU5003 (trade name, manufactured by Sumitomo Chemical Co., Ltd., metallocene low density polyethylene, density 0.928 g / cm ³ )
Ethylene-vinyl acetate copolymer: VF120S (trade name, manufactured by Ube Industries, vinyl acetate component content 20%)
Ethylene-acrylate ester copolymer: NUC6510 (trade name, manufactured by NUC, ethylene-ethyl acrylate copolymer, acrylate component content 23 mass%, density 0.93 g / cm ³ )
(Other ingredients)
Styrenic thermoplastic elastomer: Tuftec N504 (trade name, manufactured by Asahi Kasei Chemicals, hydrogenated SEBS)
Mineral oil: Diana Process Oil PW90 (trade name, manufactured by Idemitsu Kosan Co., Ltd., paraffinic oil)
Silane grafter: Linkron XCF730N (trade name, manufactured by Mitsubishi Chemical Corporation, resin obtained by silane-grafting linear low density polyethylene)
<Inorganic filler>
Magseeds FK621 (trade name, manufactured by Kamishima Chemical Industries, magnesium hydroxide)
<Additive)
Acrylic polymer 1: Methbrene L-1000 (trade name, manufactured by Mitsubishi Rayon Co., Ltd., mass average molecular weight 270,000)
Acrylic polymer 2: methabrene P-501A (trade name, manufactured by Mitsubishi Rayon Co., Ltd., mass average molecular weight 800,000)
Acrylic polymer 3: Metabrene P-530A (trade name, manufactured by Mitsubishi Rayon Co., Ltd., mass average molecular weight 3.1 million)
Acrylic polymer 4: ARUFON UP-1170 (trade name, manufactured by Toagosei Co., Ltd., mass average molecular weight: 8,000)
Fluoropolymer: Metablen A-3300 (trade name, manufactured by Mitsubishi Rayon Co., Ltd., acrylic-modified polytetrafluoroethylene)
Oleamide: Armoslip CP (trade name, manufactured by Lion Specialty Chemicals)
Calcium stearate: Ca-St (trade name, manufactured by Nitto Kasei Co., Ltd.)
Silicone gum: X-21-3043 (trade name, manufactured by Shin-Etsu Silicone)
Polyethylene wax: AC polyethylene no. 6 (trade name, manufactured by Honeywell)
<Silane coupling agent>
KBM1003 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., vinyltrimethoxysilane)
<Organic peroxides>
Perhexa 25B (trade name, manufactured by NOF Corporation, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, decomposition temperature 179 ° C.)
<Silanol condensation catalyst>
ADK STAB OT-1 (trade name, manufactured by ADEKA, dioctyltin dilaurate)

(Examples 1-13, Comparative Examples 1-8)
First, an inorganic filler and a silane coupling agent are put into a 10 L Henschel mixer manufactured by Toyo Seiki at a mass ratio shown in Tables 1 and 2, and mixed at room temperature (25 ° C.) for 1 hour to obtain a powder mixture. It was. Here, such a mixing method is referred to as pre-blend (PB).
Next, each component shown in the base resin column of Table 1 and Table 2 was put into a 2 L Banbury mixer made by Nippon Roll, and each component was melted. Thereafter, the powder mixture, the organic peroxides shown in Tables 1 and 2 and the components shown in the additive column were introduced into the Banbury mixer at the mass ratio shown in Tables 1 and 2, and the organic peroxides were added. After melting and mixing at a temperature equal to or higher than the decomposition temperature of the product, specifically 190 ° C. for 10 minutes, the material was discharged at a material discharge temperature of 190 ° C. to obtain Silane MB. The obtained silane MB contains a silane crosslinkable resin obtained by grafting a silane coupling agent to the base resin.

  Next, Silane MB and silanol condensation catalyst were charged into a closed ribbon blender and dry blended at room temperature (25 ° C.) for 5 minutes to obtain a dry blend (master batch mixture). At this time, the mixing ratio of the silane MB and the silanol condensation catalyst is a mass ratio shown in Tables 1 and 2.

Next, the obtained dry blend was introduced into a 25 mmφ extruder (L / D (ratio of screw effective length L to diameter D) = 25). While melt-mixing the dry blend in this extruder, the outer diameter is 2.4 mmφ and the insulation thickness is 0.8 mm around the conductor (bare annealed copper wire, 0.8 mmφ) under the following extrusion temperature conditions. The coated conductor was obtained by coating at a linear speed of 10 m / min.
The temperature conditions were set such that the die temperature in the extruder was 200 ° C., and then toward the feeder side, C3 zone = 180 ° C., C2 zone = 150 ° C., C1 zone = 130 ° C.
The obtained coated conductor was allowed to stand at room temperature (23 ° C., 50% RH) for 24 hours, and the coated conductor (a molded body of the silane crosslinkable composition) was brought into contact with water.
Thus, the electric wire which has the coating layer which consists of a silane crosslinked resin molding on the outer peripheral surface of the said conductor was manufactured. The silane cross-linked resin molding as the coating layer has the above-mentioned silane cross-linked resin.

(Example 14)
Without preparing the powder mixture, each component shown in the base resin column of Table 1, the inorganic filler, the silane coupling agent, the organic peroxide, and each component shown in the additive column, in the mass ratio shown in Table 1, Silane MB was obtained in the same manner as in Example 2 except that it was put in a 2 L Banbury mixer manufactured by Nippon Roll. Here, such simultaneous mixing is called all blend (AB).
Moreover, the coated conductor and the electric wire were obtained like Example 2 except having used silane MB obtained above.

  Each manufactured electric wire was subjected to the following test, and the results are shown in Tables 1 and 2.

1. Mayan When extruding an electric wire under the conditions described above, the production length at the time when the meani adhered to the surface of the electric wire was measured. When the production length is 1000 m or more, A (highly excellent), 500 m or more but less than 1000 m is B (excellent), 300 m or more but less than 500 m is C (good), 200 m or more but less than 300 m is D (possible), and less than 200 m is E ( Failed).

2. Appearance When manufacturing the electric wire, if the surface of the electric wire is very clean and has a good appearance, “AA (advanced)”. “E” (rejected) was defined as a gel surface or rough surface on the electric wire surface.

3. Bleed out (reference test)
The manufactured electric wire was left in an environment of 23 ° C. and 50% RH. “A (advanced)” means that the surface of the electric wire does not change even if it is left for 6 months or longer, and oil that oozes out on the surface of the wire in more than 1 month but less than 6 months “B”, and “E” that exudes less than a month. This evaluation is a reference test.

4). Heat shrinkage Heat shrinkage was measured in order to confirm whether sufficient cross-linking progressed and it had heat resistance.
The conductor was pulled out of the manufactured electric wire to obtain a 200 mm tubular piece, which was then left in a thermostatic bath at 100 ° C. for 22 hours and then left at room temperature for 3 hours, and the heat shrinkage was calculated by the following formula.
Heat shrinkage rate (%) = {(initial length) − (length after heating)} / (initial length) × 100
Heat shrinkage of less than 3% is “A (advanced)”, 3% to less than 5% is “B (good)”, and 5% to less than 8% is “C (good)”, 8 % Or more was designated as “E (failed)”.

As is apparent from the results shown in Tables 1 and 2, Examples 1 to 14 all passed the Meani, appearance test, and heat shrink test. Thus, according to the present invention, an electric wire having a coating layer of a silane cross-linked resin molded body having reduced appearance and heat resistance, capable of continuous extrusion of 1000 m or more, and having excellent appearance and heat resistance. I was able to manufacture it.
Furthermore, in Examples 1 to 12 and 14 using an acrylic polymer having a mass average molecular weight of 100,000 or more, bleeding out was suppressed. According to the present invention, in addition to the above-described excellent characteristics, an electric wire having a silane cross-linked resin molded article having a more excellent appearance as a coating layer could be produced.

  On the other hand, in Comparative Example 1 using a fluoropolymer, a sag was generated when the production length was less than 200 m, and the appearance of the obtained electric wire was inferior. In Comparative Example 2 in which oleic acid amide was used, the product was generated with a manufacturing length of less than 200 m, and scouring occurred. Comparative Example 3 using calcium stearate was inferior in appearance. In both Comparative Example 4 using the silicone gum and Comparative Example 5 using the polyethylene wax, the production length was less than 200 m, and scum was generated. In Comparative Example 6 in which silane MB having too little acrylic polymer was used, the production length was less than 200 m, and scum was generated. Comparative Example 7 using silane MB with too much acrylic polymer failed the heat shrinkage test. A bleed-out was also observed. Comparative Example 8 using silane grafter as the base resin failed the heat shrinkage test.

Claims (13)

0.1 to 20 parts by mass of an acrylic polymer, 0.003 to 0.3 parts by mass of an organic peroxide, and 0.5 to 400 parts by mass of an inorganic filler with respect to 100 parts by mass of the polyolefin base resin or rubber. And a step (a) of preparing a silane masterbatch by melt-mixing 2 parts by mass of the silane coupling agent and 15.0 parts by mass or less at a temperature equal to or higher than the decomposition temperature of the organic peroxide,
A step (b) of molding after mixing the silane masterbatch obtained in the step (a) and a silanol condensation catalyst;
A step (c) of bringing the molded product obtained in the step (b) into contact with moisture and crosslinking;
The manufacturing method of the silane crosslinked resin molding which has this.   The method for producing a silane-crosslinked resin molded article according to claim 1, wherein the acrylic polymer has a mass average molecular weight of 100,000 to 1,000,000.   The method for producing a silane-crosslinked resin molded article according to claim 1 or 2, wherein the acrylic polymer is 0.5 to 10 parts by mass with respect to 100 parts by mass of the polyolefin base resin or rubber.   The method for producing a silane-crosslinked resin molded body according to any one of claims 1 to 3, wherein the acrylic polymer is 1 to 6 parts by mass with respect to 100 parts by mass of the polyolefin base resin or rubber.   The method for producing a silane-crosslinked resin molded article according to any one of claims 1 to 4, wherein the silane coupling agent is vinyltrimethoxysilane or vinyltriethoxysilane.   The method for producing a silane-crosslinked resin molded article according to any one of claims 1 to 5, wherein the inorganic filler contains silica, boehmite, clay, talc, aluminum hydroxide, magnesium hydroxide, calcium carbonate, or a combination thereof. .   The method for producing a silane-crosslinked resin molded article according to any one of claims 1 to 6, wherein the melt mixing in the step (a) is performed using a closed mixer. 0.1 to 20 parts by mass of an acrylic polymer, 0.003 to 0.3 parts by mass of an organic peroxide, and 0.5 to 400 parts by mass of an inorganic filler with respect to 100 parts by mass of the polyolefin base resin or rubber A silane masterbatch used for producing a masterbatch mixture obtained by mixing 2 parts by mass of a silane coupling agent and 15.0 parts by mass or less with a silanol condensation catalyst,
A silane master batch obtained by melting and mixing all or part of the base resin, the organic peroxide, the inorganic filler, and the silane coupling agent at a temperature equal to or higher than the decomposition temperature of the organic peroxide.   A masterbatch mixture containing the silane masterbatch according to claim 8 and a silanol condensation catalyst.   The molded object which introduce | transduced and shape | molded the masterbatch mixture formed by dry-blending the silane masterbatch of Claim 9, and a silanol condensation catalyst into a molding machine.   A silane cross-linked resin molded product produced by the method for producing a silane cross-linked resin molded product according to any one of claims 1 to 7.   The silane cross-linked resin molded article according to claim 11, wherein the base resin is cross-linked with the inorganic filler through a silanol bond.   A heat-resistant product comprising the silane-crosslinked resin molded article according to claim 11 or 12.