JP6969082B2 - Catalyst batch, electric wire / cable formed using it, and its manufacturing method - Google Patents

Description

The present invention relates to a catalyst batch, an electric wire / cable formed using the catalyst batch, and a method for manufacturing the same.

An electric wire / cable used for supplying electric power or transmitting an electric signal to an electric device is provided with an insulating layer or a sheath as a coating layer on the surface thereof.

The coating layer is required to have rubber elasticity so as not to be crushed by external pressure. In addition, electric wires and cables may be exposed to high temperatures, and heat resistance against this is also required.

As a method for exhibiting rubber elasticity and heat resistance, it is known to apply a cross-linking treatment to a coating layer. The cross-linking treatment includes electron beam cross-linking, chemical cross-linking, and silane cross-linking. Among these, silane cross-linking is adopted in various fields because it does not require special equipment.

Silane cross-linking involves graft-polymerizing a silane compound (eg, a silane coupling agent) onto a polymer in the presence of a free radical generator to obtain a silane graft polymer, followed by watering the silane graft polymer in the presence of a silanol condensation catalyst. It is a method of introducing a crosslinked structure by contacting with.

When the coating layer of an electric wire or a cable is formed by silane cross-linking, first, a silane batch containing a silane graft polymer and a catalyst batch containing a silanol condensation catalyst (hereinafter, also simply referred to as a catalyst) and a polymer are mixed while being melted. Subsequently, this mixture is extruded to the outer periphery of the conductor for molding. Then, the molded product is brought into contact with water to carry out silane cross-linking (see, for example, Patent Document 1). As described above, in order to form the coating layer by silane cross-linking, it is necessary to mix the silane batch and the catalyst batch before extrusion.

Japanese Unexamined Patent Publication No. 2008-297453

According to the studies by the present inventors, however, in the silane crosslinking method shown in Patent Document 1, the crosslinking reaction unintentionally proceeds during the melt-kneading of the silane batch and the catalyst batch, so that the crosslinking reaction proceeds unintentionally. It was found that the coating layer to be coated had a poor appearance. In particular, the higher the catalyst concentration for the purpose of improving heat resistance and rubber elasticity, the more remarkable the poor appearance becomes.

Specifically, if the catalyst concentration in the catalyst batch is increased, it becomes difficult to uniformly disperse the catalyst in the silane batch when the catalyst batch and the silane batch are mixed. Therefore, in the mixture of the catalyst batch and the silane batch, a region where the catalyst aggregates is formed. In such a region, the cross-linking reaction proceeds rapidly, and a highly viscous cross-linked product is likely to be formed. Such a crosslinked product becomes a foreign substance when the mixture is extruded to form a coating layer, which causes surface roughness of the coating layer and reduces surface smoothness.

On the other hand, in order to improve the surface smoothness, it is conceivable to reduce the catalyst concentration and suppress the aggregation of the catalyst, but in this case, a sufficient degree of cross-linking cannot be obtained in the coating layer, and the heat resistance required for the coating layer is high. It becomes difficult to satisfy the sex.

In this way, when the coating layer is formed by silane cross-linking, the cross-linking proceeds from the mixing of the silane batch and the catalyst batch to the extrusion due to the dispersibility of the catalyst, so that the coating layer has heat resistance (heat resistance ( It has been difficult to achieve both heat aging resistance and heat deformation resistance) and surface smoothness. In particular, it has been difficult to suppress the deformability (heat deformability) at high temperatures, that is, to improve the heat deformability.

Therefore, an object of the present invention is to provide a technique for forming a coating layer having excellent heat resistance and surface smoothness and suppressed heat deformation by silane crosslinking.

According to one aspect of the invention
It is a catalyst batch for blending into a silane batch containing a silane graft polymer in which a silane compound is graft-polymerized with a polymer and cross-linking the silane.
A silane graft polymer (A) in which a silane compound is graft-polymerized in the presence of a free radical generator on a polymer (a) containing polyolefin, and
Containing silanol condensation catalyst (B),
The polymer (a) is a semi-crystalline chlorinated polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 10 parts by mass or more with respect to 100 parts by mass of the polymer (a). Contains at least one of 70 parts by mass or less of linear low density polyethylene.
In the silane graft polymer (A), the silane compound is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer (a), and the ratio of the silane compound to the free radical generator is 5 or more. Graft-polymerized to 400 or less,
A catalyst batch containing the silanol condensation catalyst (B) in an amount of 0.01 parts by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a) is provided.

According to another aspect of the invention.
A polymer (a) containing a polyolefin, which is 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 100 parts by mass of the polymer (a). With respect to 100 parts by mass of the polymer (a) containing at least one of linear low-density polyethylene of 10 parts by mass or more and 70 parts by mass or less, 1 part by mass or more of the silane compound and 10 parts by mass or less of the free radical generator. The silane compound is added so that the ratio of the silane compound to the free radical generator is 5 or more and 400 or less, and the silane compound is graft-polymerized in the presence of the free radical generator in the polymer (a) to obtain a silane graft polymer. While forming (A), the silanol condensation catalyst (B) is added to the silane graft polymer (A) so as to be 0.01 part by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a). By doing so, the polymer batch preparation process to obtain the polymer batch and
The catalyst batch and the silane batch containing the silane graft polymer obtained by graft-polymerizing the silane compound on the polymer are mixed in the range of 10:90 to 90:10, and the mixture is extruded so as to cover the outer periphery of the conductor and molded. The extrusion process to get the body and
Provided is a method for manufacturing an electric wire / cable having a cross-linking step of cross-linking the molded product with silane to form a coating layer.

According to still another aspect of the invention.
A conductor and a coating layer arranged on the outer circumference of the conductor are provided.
The coating layer is formed by silane cross-linking a mixture containing a silane batch containing a silane graft polymer graft-polymerized with a silane compound and a catalyst batch in the range of 10:90 to 90:10.
The catalyst batch is
A silane graft polymer (A) in which a silane compound is graft-polymerized in the presence of a free radical generator on a polymer (a) containing polyolefin, and
Containing silanol condensation catalyst (B),
The polymer (a) is a semi-crystalline chlorinated polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 10 parts by mass or more with respect to 100 parts by mass of the polymer (a). Contains at least one of 70 parts by mass or less of linear low density polyethylene.
In the silane graft polymer (A), the silane compound is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer (a), and the ratio of the silane compound to the free radical generator is 5 or more. Graft-polymerized to 400 or less,
An electric wire / cable containing the silanol condensation catalyst (B) in an amount of 0.01 parts by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a) is provided.

According to the present invention, a coating layer having excellent heat resistance and surface smoothness and suppressed heat deformation can be formed by silane crosslinking.

It is a figure which shows the cross section perpendicular to the length direction of the electric wire which concerns on one Embodiment of this invention. It is a figure which shows the cross section perpendicular to the length direction of the cable which concerns on one Embodiment of this invention. It is a schematic diagram which shows an example of the electric wire manufacturing apparatus which concerns on one Embodiment of this invention.

The present inventors investigated the dispersion of the catalyst in order to suppress an unintended cross-linking reaction that occurs between mixing and extruding the catalyst batch and the silane batch. As a result, it was found that it is preferable to use a silane graft polymer as a dispersion medium for the catalyst. That is, it was found that the catalyst should be dispersed in the silane graft polymer to form a catalyst batch.

According to such a catalyst batch, the catalyst is pre-dispersed in the silane graft polymer, and the catalyst batch itself is easily mixed with the silane batch containing the silane graft polymer, so that even when the catalyst concentration is increased. , The catalyst can be dispersed well without agglomeration. This makes it possible to suppress the cross-linking reaction due to the aggregation of the catalyst and suppress the generation of foreign substances. Therefore, by using a catalyst batch having a high catalyst concentration, it is possible to form a coating layer having excellent heat resistance and surface smoothness.

Furthermore, the present inventors use a polymer containing at least one of semi-crystalline chlorinated polyethylene and linear low-density polyethylene as the polymer for graft-polymerizing the silane compound when preparing the silane graft polymer used for the catalyst batch. Therefore, it was found that the deformability at high temperature (heat deformability) is suppressed, that is, the heat deformability is improved.

The present invention has been made based on the above findings.

<One Embodiment of the present invention>
Hereinafter, an embodiment of the present invention will be described.
The numerical range represented by using "~" in the present specification means a range including the numerical values before and after "~" as the lower limit value and the upper limit value.

[Catalyst batch]
The catalyst batch is a component for promoting silane cross-linking of a silane graft polymer by blending it into a silane batch containing a silane graft polymer obtained by graft-polymerizing a silane compound on the polymer.

In the present embodiment, the catalyst batch is configured as follows from the viewpoint of enhancing the dispersibility of the catalyst.

That is, the catalyst batch contains a silane graft polymer (A) in which a silane compound is graft-polymerized on a polymer (a) containing polyolefin in the presence of a free radical generator, and a silanol condensation catalyst (B). (A) is a semi-crystalline chlorinated polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a). In the silane graft polymer (A), the silane compound is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer (a), and is a free radical generator. It is graft-polymerized so that the ratio of the silane compound to the polymer (a) is 5 or more and 400 or less, and the amount of the silanol condensation catalyst (B) is 0.01 parts by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a). Included in.

Hereinafter, each component constituting the catalyst batch will be described.

(Silane Graft Polymer (A))
The silane graft polymer (A) is a polymer (a) containing polyolefin and a silane compound graft-polymerized in the presence of a free radical generator, and is a dispersion medium for dispersing the silanol condensation catalyst (B) in a catalyst batch. Acts as.

The polyolefin contained in the polymer (a) is not particularly limited as long as it can graft-polymerize a silane compound, and known components can be used. For example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-glycidyl methacrylate. A copolymer or the like can be used.

EVA has high acceptability for silanol condensation catalyst (B) and other additives (for example, flame retardant), and even if a large amount of these is blended, it can be uniformly dispersed without agglomeration, and is preferably used. can.

Further, LLDPE can be preferably used as the polyolefin contained in the polymer (a). By setting the blending amount of LLDPE to 10 parts by mass to 70 parts by mass with respect to 100 parts by mass of the polymer (a), the heat deformability of the coating layer can be suppressed. If it is less than 10 parts by mass, the heat deformability cannot be sufficiently suppressed. On the other hand, if it exceeds 70 parts by mass, melt fracture occurs when the coating layer is extruded, and the surface smoothness deteriorates (the appearance becomes rough).

As the polymer (a), semi-crystalline chlorinated polyethylene (CPE) can be preferably used in addition to the polyolefin. By setting the blending amount of the semi-crystalline CPE to 10 parts by mass to 70 parts by mass with respect to 100 parts by mass of the polymer (a), the heat deformability of the coating layer can be suppressed. If it is less than 10 parts by mass, the heat deformability cannot be sufficiently suppressed. On the other hand, if it exceeds 70 parts by mass, the elongation characteristics after the heat aging test are inferior. This is considered to be due to dehydrochlorination at high temperature.

As the semi-crystalline CPE used for the polymer (a), it is preferable that the crystal residue obtained by differential scanning calorimetry (DSC) measurement (that is, the amount of crystal melting indicating the crystal residue) is 10 J / g to 50 J / g. .. By using a semi-crystalline CPE having a crystal residue within such a range, the thermal deformability of the coating layer can be suppressed. Here, the calorific value of crystal melting by DSC measurement refers to a value calculated from the total crystal peak area of the DSC chart measured at a heating rate of 10 ° C./min using a differential scanning calorimeter.

As described above, from the viewpoint of suppressing the heat deformability, the polymer (a) is a semi-crystalline CPE of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 100 parts by mass of the polymer (a). It is preferable to contain at least one of LLDPE of 10 parts by mass or more and 70 parts by mass or less.

The silane compound is a silane coupling agent having an unsaturated binding group capable of reacting with a polymer and a hydrolyzable silane group capable of forming a crosslink by a silanol condensation reaction. The silane compound is graft-polymerized on the polymer (a) to introduce a silane group into the polymer (a).

Examples of unsaturated binding groups include vinyl groups, methacrylic groups and acrylic groups. Examples of the hydrolyzable silane group include those having a hydrolyzable structure such as a halogen, an alkoxy group, an acyloxy group and a phenoxy group. Examples of the silane group having a hydrolyzable structure include a halosilyl group, an alkoxysilyl group, an asyloxysilyl group, and a phenoxysilyl group.

The blending amount of the silane compound is 1 part by mass to 10 parts by mass with respect to 100 parts by mass of the polymer (a). If it is less than 1 part by mass, when the coating layer is formed by silane crosslinking, a sufficient degree of crosslinking cannot be obtained and the heat resistance becomes low. On the other hand, if it exceeds 10 parts by mass, when the silane graft polymer (A) is formed by graft polymerization, the silane compounds easily react with each other to form a foreign substance (condensate), resulting in poor appearance in the coating layer. , Surface smoothness is impaired. From the viewpoint of achieving both heat resistance and surface smoothness at a higher level, the blending amount of the silane compound is preferably 2 parts by mass to 6 parts by mass.

The free radical generator decomposes by heating to generate radicals. As the free radical generator, for example, an organic peroxide can be used. Specifically, dicumyl peroxide, 1,1-di (t-butylperoxy) cyclohexane, t-butylperoxyisopropylcarbonate, t-amylperoxyisopropylcarbonate, 2,5dimethyl2.5di (t). -Butylperoxy) hexane, di-t-butyl peroxide, di-t-amyl peroxide, 1,1-di (t-amylperoxy) cyclohexane, t-butylperoxy 2-ethylhexyl carbonate, etc. should be used. Can be done. These may be used alone or in combination of two or more.

The blending amount of the free radical generator is such that the mass ratio of the silane compound to the free radical generator (silane compound / free radical generator) is 5 to 400, preferably 100 to 300. If the ratio is less than 5, and the amount of the free radical generator is relatively large, the number of cross-linking points of the polymer increases, and the rate of cross-linking formation at the initial stage of the reaction becomes excessively high, so that the polymer weight of the polymers increases. , Grains are formed due to the difference in viscosity, and the surface smoothness is impaired. On the other hand, if the ratio exceeds 400, the amount of free radical generator is excessively reduced, so that a sufficient degree of cross-linking cannot be obtained and the heat resistance is lowered.

(Silanol condensation catalyst (B))
The catalyst (B) promotes the condensation of the silane groups introduced into the silane graft material contained therein when the catalyst batch and the silane batch are mixed, and makes the formation of the crosslinked structure efficient.

As the catalyst (B), known compounds can be used, for example, group II elements such as magnesium and calcium, group VIII elements such as cobalt and iron, metal elements such as tin, zinc and titanium, and these elements. Metal compounds containing can be used. Further, metal salts of octylic acid and adipic acid, amine compounds, acids and the like can be used. Specifically, as metal salts, dioctyl tin dineodecanoate, dibutyl tin dilaurylate, dibutyl tin diacetate, dibutyl tin dioctaate, stannous acetate, stannous cabrylate, lead naphthenate, zinc caprylate, naphthen Cobalt acid or the like can be used. As the amine compound, ethylamine, dibutylamine, hexylamine, pyridine and the like can be used. As the acid, an inorganic acid such as sulfuric acid or hydrochloric acid, or an organic acid such as toluenesulfonic acid, acetic acid, stearic acid or maleic acid can be used.

The blending amount of the catalyst (B) is 0.01 part by mass to 1 part by mass, preferably 0.03 part by mass to 0.3 part by mass with respect to 100 parts by mass of the polymer (a). If it is less than 0.01 parts by mass, a sufficient degree of cross-linking cannot be obtained and the heat resistance becomes low. On the other hand, if it exceeds 1 part by mass, crosslinking tends to proceed until the silane batch is mixed and extruded, and the surface smoothness is impaired.

(Other additives)
If necessary, the catalyst batch may contain other additives.

For example, a flame retardant can be contained for the purpose of improving the flame retardancy of the coating layer. The flame retardant includes an antimony compound such as antimony trioxide, a non-halogen flame retardant such as aluminum hydroxide and magnesium hydroxide, a halogen flame retardant having a halogen element such as bromine in the molecule, and a phosphorus element in the molecule. A phosphorus-based flame retardant, cyanuric acid, a derivative of isocyanuric acid, or the like can be used. These may be used individually by 1 type and may be used in combination of 2 or more type. The amount of the flame retardant to be blended is not particularly limited, but for example, it may be blended so as to be 60 parts by mass to 300 parts by mass with respect to 100 parts by mass of the polymer (a).

Further, for example, other additives such as a plasticizer, an antioxidant (including an antioxidant), a filler such as carbon black, a lubricant, a copper damage discoloration inhibitor, a cross-linking aid, and a stabilizer may be contained. ..

[Preparation of catalyst batch]
Next, the method for preparing the catalyst batch described above will be described.

First, a predetermined amount of the silane compound and the free radical generator are added to the polymer (a). By melt-kneading these at a predetermined temperature, the silane compound is graft-polymerized on the polymer (a) to form the silane graft polymer (A). At this time, at the same time as melt-kneading and graft polymerization, a predetermined amount of silanol condensation catalyst (B) is added to the silane graft polymer (A). That is, in the present embodiment, the silanol condensation catalyst (B) is dispersed in the silane graft polymer (A) while graft-polymerizing the silane compound on the polymer (a). By dispersing the catalyst (B) at the same time as the graft polymerization in this way, the catalyst (B) can be uniformly dispersed in the silane graft polymer (A). Moreover, the progress of the cross-linking reaction during melt-kneading can be suppressed, and the generation of cross-linked products (foreign substances) in the catalyst batch can be suppressed. If the catalyst (B) is to be dispersed after the graft polymerization, not only the catalyst (B) cannot be dispersed uniformly, but also the cross-linking reaction proceeds and foreign matter is formed. On the contrary, if the catalyst (B) is dispersed in advance before the graft polymerization, the polymer (a) becomes slippery due to the viscous catalyst (B). Therefore, when the silane compound is added and the graft polymerization is carried out, the silane Dispersion of the compound is hindered and uniform graft polymerization cannot be performed. Not only that, the contact time between the catalyst (B) and the silane compound becomes long, and an unintended cross-linking reaction tends to proceed.

The catalyst batch is configured such that the catalyst (B) is uniformly dispersed in the silane graft polymer (A). Moreover, since it is prepared by performing polymerization and dispersion at the same time, an unintended cross-linking reaction during preparation is suppressed, and the generation of foreign substances (cross-linked products) due to cross-linking is reduced.

The catalyst (B) may be added in a liquid state, but if it is difficult to add the catalyst (B), it is impregnated with another additive (for example, a flame retardant) and then added, or the polymer (a) is added. ) May be dispersed and added as a mixture.

When an antioxidant is added as another additive, it may be added after a predetermined time has elapsed from the start of the polymerization so as not to inhibit the graft polymerization of the silane compound. For example, it may be added at the same time as the catalyst (B).

〔Electrical wire〕
Next, a method of manufacturing an electric wire using the above-mentioned catalyst batch and a schematic structure of the electric wire will be described with reference to FIGS. 1 and 3. FIG. 1 is a diagram showing a cross section perpendicular to the length direction of an electric wire according to an embodiment of the present invention. FIG. 3 is a schematic view showing an example of an electric wire manufacturing apparatus.

First, the conductor 11 is prepared. As the conductor 11, for example, a copper wire made of low-oxygen copper or oxygen-free copper, a copper alloy wire, a metal wire made of aluminum, silver or the like, or a stranded wire obtained by twisting metal wires can be used. The outer diameter of the conductor 11 can be appropriately changed according to the use of the electric wire 10.

Subsequently, the polymer (a), the silane compound, the free radical generator, and the catalyst (B) are prepared, and the catalyst batch 13 in which the catalyst (B) is dispersed in the silane graft polymer (A) is prepared by the above-mentioned procedure. .. At this time, if necessary, another additive (for example, a flame retardant, an antioxidant, etc.) may be blended and dispersed in the catalyst batch 13.

Further, separately from the preparation of the catalyst batch 13, a silane batch 14 containing a silane graft polymer obtained by graft-polymerizing a silane compound on the polymer is prepared. This graft polymerization may be carried out in the same manner as in the catalyst batch 13.

The polymer in the silane batch 14 is not particularly limited, and may be appropriately changed according to the characteristics required for the insulating layer 12. From the viewpoint of flexibility, for example, EVA, an ethylene-ethyl acrylate copolymer (EEA), an ethylene-based α-olefin copolymer, or the like may be used. Further, from the viewpoint of strength, for example, a copolymer with a propylene-based α-olefin may be used. From the viewpoint of achieving both flexibility and strength, it is advisable to use these polymers together. As the silane compound to be graft-polymerized on the polymer in the silane batch 14, the above-mentioned compound may be used.

Subsequently, the catalyst batch 13 and the silane batch 14 prepared above are supplied to the extruder 100, melt-kneaded and mixed, and the mixture 15 is extruded and coated on the outer periphery of the conductor 11. In the catalyst batch 13 of the present embodiment, since the catalyst (B) is dispersed in the silane graft polymer (A), when mixed with the silane batch 14, the catalyst (B) is dispersed in the mixture 15 without aggregating. Can be made to. As a result, it is possible to prevent the cross-linking reaction from proceeding until the mixture is mixed and extruded, and the generation of foreign substances in the extruded molded product can be reduced.

The catalyst batch 13 and the silane batch 14 are mixed at a mass ratio in the range of 10:90 to 90:10 (the numerical value on the left side represents the ratio of the catalyst batch 13 and the numerical value on the right side represents the ratio of the silane batch 14). For example, the ratio of 10:90 may be expressed as "10/90", or the ratio of 90:10 may be expressed as "90/10" (the numerical value on the numerator side represents the ratio of the catalyst batch 13 and the denominator. The number on the side represents the ratio of the silane batch 14). If the blending amount of the catalyst batch 13 is excessively small, the degree of cross-linking of the insulating layer 12 becomes insufficient, and the desired heat resistance cannot be obtained. On the other hand, if the compounding amount of the catalyst batch 13 is excessively large, the compounding amount of the silane batch 14 becomes small, the degree of cross-linking of the insulating layer 12 becomes insufficient, and the desired heat resistance cannot be obtained.

Subsequently, the molded product is subsequently exposed to, for example, the atmosphere and brought into contact with moisture. As a result, the silane groups of the silane graft polymer (A) in the catalyst batch 13 and the silane graft polymer in the silane batch 14 are hydrolyzed to form silanol groups. Then, a crosslinked structure is introduced by dehydrating and condensing these silanol groups with each other by the catalyst (B). In this way, the mixture 15 of the catalyst batch 13 and the silane batch 14 is crosslinked with silane to form an electrically insulating insulating layer 12 made of a crosslinked silane.

From the above, the electric wire 10 of this embodiment is obtained.

<Effects of this embodiment>
According to this embodiment, one or more of the following effects are exhibited.

The catalyst batch of the present embodiment is configured such that the silanol condensation catalyst (B) is uniformly dispersed in the silane graft polymer (A). That is, the catalyst batch is in a state in which the silanol condensation catalyst (B) is dispersed in advance. Further, since the catalyst batch contains the silane graft polymer (A), it has excellent dispersibility with the silane batch containing the silane graft polymer. Furthermore, since it is prepared by performing polymerization and dispersion at the same time, an unintended cross-linking reaction during preparation is suppressed, and it is configured to reduce the generation of foreign substances (cross-linked products) associated with cross-linking. According to such a catalyst batch, even when the catalyst concentration is increased, the silanol condensation catalyst (B) aggregates and the crosslinking reaction proceeds rapidly until it is mixed with the silane batch and extruded. It can be suppressed. That is, it is possible to suppress the formation of foreign substances due to the cross-linking reaction. Therefore, according to the catalyst batch of the present embodiment, the insulating layer 12 having excellent surface smoothness and heat resistance can be formed by mixing with the silane batch and extruding.

Further, the polymer (a) to which the silane compound is graft-polymerized when preparing the silane graft polymer (A) used for the catalyst batch is a semi-crystal of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a). It contains at least one of CPE and LLDPE of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a). As a result, the heat deformability of the insulating layer 12 can be suppressed.

The catalyst batch of this embodiment further preferably contains a flame retardant. That is, the catalyst batch is preferably configured as a flame retardant-containing catalyst batch. By dispersing the flame retardant in the catalyst batch in advance, the flame retardant can be uniformly dispersed in the mixture when the catalyst batch and the silane batch are mixed. The blending amount of the flame retardant is preferably, for example, 60 parts by mass or more and 300 parts by mass or less with respect to 100 parts by mass of the polymer (a).

<Other Embodiments of the present invention>
Although one embodiment of the present invention has been specifically described above, the present invention is not limited to the above-described embodiment and can be appropriately modified without departing from the gist thereof.

In the above-described embodiment, the case where the insulating layer 12 of the electric wire 10 is formed as the covering layer has been described, but in the present invention, as shown in FIG. 2, the electrically insulating sheath of the cable 20 using the above-mentioned catalyst batch is used. 25 may be formed. Specifically, it is preferable to twist three electric wires 23 provided with an insulating layer 22 on the outer periphery of the conductor 21, press them with a pressing tape 24 or the like, and form a sheath 25 on the outer periphery thereof. The sheath 25 may be formed in the same manner as the insulating layer 12 described in the above-described embodiment.

Although FIG. 2 shows a case where three electric wires 23 are twisted together, the number of electric wires 23 is not limited to this and can be changed as appropriate.

Further, in the above-described embodiment, the flame retardant is blended in the catalyst batch, but the present invention is not limited to this. For example, a flame retardant batch containing a flame retardant may be prepared separately, and the flame retardant batch may be mixed together when the silane batch and the catalyst batch are mixed.

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

[Sample preparation method]
Samples of Examples 1 to 20 and Comparative Examples 5 to 18 were prepared by the following methods.

(Preparation of catalyst batch)
A catalyst batch was prepared as follows. The free radical generator was dissolved in a silane compound and impregnated with a powdery flame retardant in a plastic bag. Next, when the internal temperature in the 3 L kneader reached 90 ° C., the polymer was added, and when the polymer was softened, the powder impregnated with the silane compound was added and kneaded. When the temperature reached 150 ° C., a silanol condensation catalyst and an antioxidant were added, and when the internal temperature reached 160 ° C., the material was taken out. This gave a catalyst batch in which the silanol condensation catalyst was dispersed in the silane graft polymer. Then, the catalyst batch was taken out, tape-shaped with an 8-inch roll, and pelletized with a square pelletizer. The silanol condensation catalyst was added immediately before removal to suppress the cross-linking reaction in the kneader, and the antioxidant was added immediately before removal to prevent the graft polymerization of the silane compound from being inhibited. Is.

The composition of the materials in the catalyst batch (mass part of each material with respect to 100 parts by mass of the polymer) is shown in Table 1 for Examples 1 to 20 and Table 2 for Comparative Examples 5 to 18.

The following materials were used for the catalyst batches of the samples of Examples 1 to 20 and Comparative Examples 5 to 18.
-Polyolefin EVA Evaflex V5274: Mitsui-Dupont Polychemical Co., Ltd.-Polyolefin LLDPE NUCG5130: NUC Co., Ltd.-Chlorinated polyethylene semi-crystalline CPE Eraslen 402B (DSC measurement crystal residue 10J / g): Showa Denko Co., Ltd. Polyethylene Semi-Crystal CPE Eraslen 252B (DSC Measured Crystal Remaining 35J / g): Showa Denko Co., Ltd. Chlorinated Polyethylene Semi-Crystal CPE Eraslen 303B (DSC Measured Crystal Remaining 50J / g): Showa Denko Co., Ltd. Silane Compound KBM -1003: Shin-Etsu Chemical Industry Co., Ltd.-Free radical generator Park Mill D: Nichiyu Co., Ltd.-Silanol condensation catalyst Neostan U-830: Nitto Kasei Co., Ltd.-Antioxidant Irganox 1010: BASF Japan Co., Ltd.- Flame-retardant agent Antimon trioxide: Made by Twinking Star ・ Flame-retardant agent Cytex 8010: Made by Albemar Japan Co., Ltd.

(Preparation of silane batch)
Silane batches were prepared as follows. Using a 40 mm extruder, the polymer is injected from the hopper, a solution in which a free radical generator is dissolved in a silane compound is injected with a liquid addition pump, and the cylinder temperature is set to 200 ° C. and the residence time in the extruder is set to 100 to 150 seconds. , A silane graft polymer was prepared by extruding into a strand shape and graft-polymerizing a silane compound having a diameter of 2 mm to 3 mm with a pelletizer.

As the materials used for the silane batch, the polymer is V5274 (EVA Evaflex: manufactured by Mitsui DuPont Polychemical Co., Ltd.), the silane compound is KBM-1003 (manufactured by Shin-Etsu Chemical Co., Ltd.), and the free radical generator is Park Mill D (Nippon Oil Co., Ltd.). (Manufactured by Co., Ltd.), 4 parts by mass of the silane compound and 0.1 part by mass of the free radical generator were mixed with 100 parts by mass of the polymer.

(Making electric wires)
As described below, a coating layer was formed using the catalyst batch and the silane batch prepared above, and an electric wire was produced. The pellets of the catalyst batch and the pellets of the silane batch are mixed and charged into a 20 mm extruder from the hopper, and the residence time in the extruder is set to 120 to 150 seconds at a cylinder temperature of 180 ° C and a die temperature of 200 ° C. The outer periphery was extruded and coated so that the coating thickness was 0.4 mm. As the conductor, a core wire having a diameter of 0.8 mm was used. The mixing ratio of the catalyst batch (catalyst MB) to the silane batch (silane MB) is shown in Table 1 for Examples 1 to 20 and Table 2 for Comparative Examples 5 to 18.

Then, the extruded-coated conductor was left at a temperature of 80 ° C. in an environment where moisture was present for 24 hours, and was crosslinked with silane to form an insulating layer, thereby producing an electric wire.

Further, the samples of Comparative Examples 1 to 4 were prepared by the following methods.

In Examples 1 to 20 and Comparative Examples 5 to 18, a catalyst batch using a silane graft polymer and a silane batch were used to form a coating layer to prepare an electric wire, whereas in Comparative Example. In 1 to Comparative Example 4, a coating layer was formed by using a catalyst batch without a silane graft polymer and a silane batch to prepare an electric wire.

The following were prepared as catalyst batches without using a silane graft polymer.
A composition (MB1) in which EVA V5274 is kneaded at a ratio of 99 parts by mass and Neostan U-830 is kneaded at a ratio of 1 part by mass (catalyst content concentration 1%).
A composition (MB2) in which EVA V5274 is kneaded at a ratio of 99.9 parts by mass and Neostan U-830 is kneaded at a ratio of 0.1 parts by mass (catalyst content concentration 0.1%).

In Comparative Examples 1 to 4, the catalyst batch did not contain a flame retardant, and in the samples of Comparative Examples 1 to 4, the catalyst batch without the silane graft polymer, the flame retardant (without using the silane graft polymer). The batch and the silane batch were mixed at the time of extrusion to form a coating layer.

Regarding Comparative Examples 1 to 4, the composition of the materials in the flame-retardant batch (the mass part of each material with respect to 100 parts by mass of the polymer), the mixing ratio of the flame-retardant batch (flame-retardant MB) to the silane batch (silane MB), Table 2 shows the mixing ratio of the catalyst batch (catalyst MB1 or catalyst MB2) to the silane batch (silane MB).

〔Evaluation method〕
The produced electric wire was evaluated by the following method.

(Surface smoothness)
The smoothness of the surface of the insulating layer of the produced electric wire was visually evaluated for the presence or absence of granular protrusions. A particularly good one with a smooth feel and no granular protrusions per 5 m of wire ◎, a smooth touch with one or two granular protrusions per 5 m of wire ○, Roughness was found by touch, and 10 or more granular protrusions were visually confirmed per 5 m of electric wire. Those with a particularly rough appearance were marked with x, and those with a grade of ○ or higher (○ and ◎) were judged as acceptable.

(Tensile characteristics after heat aging)
The heat aging property was evaluated by the tensile properties after heat aging. An initial tensile test is performed on the insulating layer obtained by pulling out the core wire from the manufactured electric wire in an atmosphere of 23 ° C (± 3 ° C) and humidity 50% (± 10%), and the heat aging test is performed in a constant temperature bath. After leaving it at 158 ° C for 168 hours, a tensile test was performed within 24 hours to 48 hours in an atmosphere of 23 ° C (± 3 ° C) and humidity of 50% (± 10%) to determine the residual ratio with respect to the initial stage. Both the strength residual ratio and the elongation residual ratio were 80% or more as acceptable. In the test, both initial and heat aging had an average of n = 3, and the marked line was evaluated as 50 mm.

(Heat deformability)
The prepared electric wire was allowed to stand in a heating deformation tester at 120 ° C. for 30 minutes for preheating, and then tested under a weight of 2.5 N for 1 hour to calculate the deformation rate of the insulating layer thickness before and after the test. This test complies with JIS C 3005, but the test time was more stringently 1 hour instead of 30 minutes. Deformation rate ≤ 50% was regarded as acceptable.

(Evaluation results)
The evaluation results of Examples 1 to 20 are shown in Table 1, and the evaluation results of Comparative Examples 1 to 18 are shown in Table 2.

<Examples 1 to 20>
Examples 1 to 20 passed all of the appearance, heat aging tensile properties, and heat deformability. That is, it was confirmed in Examples 1 to 20 that a coating layer having both surface smoothness and heat resistance could be formed.

Of these, with respect to the heat deformability, as a polymer (that is, the above-mentioned polymer (a)) for graft-polymerizing a silane compound when preparing a silane graft polymer (that is, the above-mentioned silane graft polymer (A)) used for a catalyst batch. It was found that it can be suppressed by using one containing at least one of semi-crystalline CPE and LLDPE. Hereinafter, a more detailed description will be given.

As shown in Examples 1 to 20, a polymer containing polyolefin can be preferably used as the polymer (a).

As shown in Examples 1 to 8 and Examples 11 to 20, semi-crystalline CPE can be used as one viewpoint in order to suppress the heat deformability, and the polymer (a) is a polyolefin. , And a polymer (a) containing a semi-crystalline CPE of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass can be preferably used.

As the polyolefin of the polymer (a) containing the semi-crystalline CPE, as shown in Examples 1 to 8 and Examples 11 to 20, those containing at least one of EVA and LLDPE can be used. For example, as shown in Examples 1 to 8 and Examples 11 to 17, EVA can be used, and for example, as shown in Examples 19 and 20, LLDPE. It can be made of, and for example, as shown in Example 18, one containing EVA and LLDPE can be used.

As shown in Examples 1 to 8 and Examples 11 to 18, the polymer (a) containing the semi-crystalline CPE and EVA is 10 parts by mass or more and 70 parts by mass with respect to 100 parts by mass of the polymer (a). It is preferable to contain a semi-crystalline CPE of 30 parts by mass or less and EVA of 30 parts by mass or more and 90 parts by mass or less with respect to 100 parts by mass of the polymer (a).

As shown in Examples 18 to 20, the polymer (a) containing the semi-crystalline CPE and LLDPE is a semi-crystalline CPE of 30 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a). , Polymer (a) preferably contains LLDPE of 30 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass.

As another viewpoint, LLDPE can be used as shown in Examples 9, 10 and 18 to 20 in order to suppress the heat deformability, and the polymer (a) is a polyolefin. As the polymer (a), one containing 10 parts by mass or more and 70 parts by mass or less of LLDPE with respect to 100 parts by mass can be preferably used.

As the polymer (a) containing LLDPE, for example, as shown in Examples 9 and 10, those containing no semi-crystalline CPE (those made of polyolefin containing LLDPE) can be used, and for example, those containing LLDPE can be used. As shown in Examples 18 to 20, those containing semi-crystalline CPE (polyolefin containing LLDPE and those containing semi-crystalline CPE) can be used.

As the polyolefin of the polymer (a) made of the polyolefin containing LLDPE, as shown in Examples 9 and 10, those containing EVA as another polyolefin component of LLDPE can be used.

As the polyolefin containing LLDPE and the polyolefin of the polymer (a) containing semi-crystalline CPE, for example, as shown in Examples 19 and 20, those consisting of LLDPE can be used, and for example, the embodiment. As shown in Example 18, those containing EVA can be used as other polyolefin components of LLDPE.

As shown in Examples 9, 10 and 18, the polymer (a) containing the polyolefin containing LLDPE and EVA is 10 parts by mass or more and 70 parts by mass with respect to 100 parts by mass of the polymer (a). It is preferable to contain the following LLDPE and EVA of 30 parts by mass or more and 90 parts by mass or less with respect to 100 parts by mass of the polymer (a).

As described above, in order to suppress the heat deformability, the polymer (a) includes a semi-crystalline CPE of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a) and 100 parts by mass of the polymer (a). It was found that a polymer containing at least one of LLDPE of 10 parts by mass or more and 70 parts by mass or less is preferably used.

The semi-crystalline CPE used in the polymer (a) has a crystal residue of 10 J / g or more and 50 J / g or less as measured by DSC as shown in Examples 1 to 8 and Examples 11 to 20. Can be preferably used.

As shown in Examples 1 to 20, as the silane graft polymer (A), the silane compound is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer (a), and free radicals are generated. The silane compound is graft-polymerized so that the ratio of the silane compound to the agent is 5 or more and 400 or less, and the silanol condensation catalyst (that is, the silanol condensation catalyst (B) described above) is 0.01 mass by mass with respect to 100 parts by mass of the polymer (a). It is preferable to use a polymer containing 1 part or more and 1 part by mass or less.

In particular, as shown in Examples 11 to 20, the silane compound as the silane graft polymer (A) is 2 parts by mass or more and 6 parts by mass or less with respect to 100 parts by mass of the polymer (a), and is a free radical. The silane compound is graft-polymerized so that the ratio of the silane compound to the generator is 100 or more and 300 or less, and the silanol condensation catalyst (B) is 0.03 part by mass or more and 0.3 part by mass with respect to 100 parts by mass of the polymer (a). By using the following components, excellent surface smoothness was obtained, and excellent properties such as strength and elongation residual rate of heat aging tensile properties of 90% or more were obtained.

Further, as shown in Examples 1 to 20, it is preferable that the catalyst batch and the silane batch are mixed in a mass ratio in the range of 10:90 to 90:10.

<Comparative Examples 1 to 4>
In Comparative Examples 1 to 4, no silane graft polymer was used in the catalyst batch (or flame-retardant batch), and the catalyst batch and the flame-retardant batch were prepared separately. Comparative Example 1 and Comparative Example 2 had good thermal aging tensile properties, but had a rough appearance and failed in heat deformability.

Comparative Example 3 was a result of reducing the blending amount of the catalyst batch, but the appearance and the heat deformability were still unacceptable, and the heat aging tensile properties were inferior. Comparative Example 4 is a result of lowering the catalyst concentration of the catalyst batch, and although the appearance is improved, the thermal aging tensile properties and the heat deformability are rejected.

Thus, as in Comparative Examples 1 to 4, the method using no silane graft polymer in the catalyst batch did not give a sample that passed all of the appearance, heat aging tensile properties, and heat deformability. ..

<Comparative Examples 5 to 12>
In Comparative Example 5, since the blending amount of the silane compound was less than 1 part by mass, a sufficient degree of cross-linking could not be obtained and the thermal aging tensile properties were inferior. In Comparative Example 6, the blending amount of the silane compound was 10 parts by mass. If the amount exceeds the above, the reaction between the silane compounds is promoted at the time of graft copolymerization, foreign substances are generated, and the appearance is inferior.

Comparative Example 7 is inferior in thermal aging tensile properties because the blending amount of the free radical generator exceeds 400 in the mass ratio of the silane compound / free radical generator, and in Comparative Example 8, this ratio is less than 5. Therefore, the appearance is inferior. The reason for this is presumed as follows. In general, the higher the ratio of the free radical generator to the silane compound (the lower the mass ratio), the more the crosslink points of the polymer, and the higher the rate of crosslink formation at the initial stage of the reaction, but the more the free radical generator is. This is because the polymer weights of the polymers are increased, and the difference in viscosity causes the particles to become grains and cause the appearance to be rough.

In Comparative Example 9, since the blending amount of the silanol condensation catalyst contained in the catalyst batch was less than 0.01 parts by mass, the required degree of cross-linking could not be obtained and the thermal aging tensile properties were inferior. When the blending amount of the silanol condensation catalyst contained in the catalyst batch exceeds 1 part by mass, the crosslinking reaction proceeds in the extruder and the appearance is roughened.

In Comparative Example 11, the ratio of the catalyst batch to the silane batch was too small, so that the catalyst batch could not be sufficiently dispersed in the silane batch, the cross-linking reaction was hindered, and the thermal aging tensile properties were inferior. It is considered that the heat aging tensile properties are inferior because the amount of the silane batch is reduced due to the excessively large proportion of the batch.

In Comparative Examples 5 to 12, neither semi-crystalline CPE nor LLDPE was blended, and none of them passed the heat deformability except Comparative Example 10. Although Comparative Example 10 has passed the heat deformability, the appearance is rough.

<Comparative Example 13 to Comparative Example 18>
In Comparative Example 13, although the polymer (a) contains LLDPE, the blending amount is less than 10 parts by mass, and in Comparative Example 14, although the polymer (a) contains semi-crystalline CPE, the blending thereof. Since the amount was less than 10 parts by mass, the thermal deformability was reduced to a value close to 50%, but it was not improved (decreased) to the acceptable range.

Comparative Example 15 and Comparative Example 17 have passed the heat deformability because the polymer (a) contains 10 parts by mass or more of LLDPE, but the blending amount of LLDPE exceeds 70 parts by mass and is excessively large. As a result, melt fracture occurs during extrusion, resulting in a rough appearance.

Comparative Example 16 and Comparative Example 18 have passed the heat deformability because the polymer (a) contains 10 parts by mass or more of semi-crystalline CPE, but the blending amount of the semi-crystalline CPE exceeds 70 parts by mass. If it is excessively large, dehydrochloric acid will occur in the high temperature and long-term test in the heat aging test, and the residual elongation rate will be inferior. When semi-crystalline CPE is used, better surface smoothness is obtained even when the blending amount is excessively large as compared with the case where LLDPE is used.

In Comparative Examples 13 to 18, by blending at least one of semi-crystalline CPE and LLDPE, improvement (decrease) in heat deformability is observed.

As described above, according to the present invention, by using a catalyst batch in which a silanol condensation catalyst is dispersed in a silane graft polymer, both heat resistance (heat resistance aging resistance and heat deformation resistance) and surface smoothness are achieved. A coating layer can be formed.

Further, by using a polymer containing at least one of semi-crystalline CPE and LLDPE as the polymer for graft-polymerizing the silane compound when preparing the silane graft polymer used for the catalyst batch, the thermal deformability of the coating layer can be suppressed. ..

<Preferable Aspect of the Present Invention>
Hereinafter, preferred embodiments of the present invention will be described.

[Appendix 1]
According to one aspect of the invention
It is a catalyst batch for blending into a silane batch containing a silane graft polymer in which a silane compound is graft-polymerized with a polymer and cross-linking the silane.
A silane graft polymer (A) in which a silane compound is graft-polymerized in the presence of a free radical generator on a polymer (a) containing polyolefin, and
Containing silanol condensation catalyst (B),
The polymer (a) is a semi-crystalline chlorinated polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 10 parts by mass or more with respect to 100 parts by mass of the polymer (a). Contains at least one of 70 parts by mass or less of linear low density polyethylene.
In the silane graft polymer (A), the silane compound is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer (a), and the ratio of the silane compound to the free radical generator is 5 or more. Graft-polymerized to 400 or less,
A catalyst batch containing the silanol condensation catalyst (B) in an amount of 0.01 parts by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a) is provided.

[Appendix 2]
In the catalyst batch of Appendix 1, preferably
The polymer (a) contains the polyolefin and the semi-crystalline chlorinated polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a).

[Appendix 3]
In the catalyst batch of Appendix 2, preferably
The polyolefin comprises at least one of the ethylene-vinyl acetate copolymer and the linear low density polyethylene.

[Appendix 4]
In the catalyst batch of Appendix 3, preferably
The polymer (a) is 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 30 parts by mass with respect to 100 parts by mass of the polymer (a). It contains 90 parts by mass or less of the above ethylene-vinyl acetate copolymer.

[Appendix 5]
In the catalyst batch of Appendix 3, preferably
The polymer (a) is 30 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 30 parts by mass with respect to 100 parts by mass of the polymer (a). It contains 70 parts by mass or less of the linear low-density polyethylene.

[Appendix 6]
In any one of the catalyst batches of Addendums 2 to 5, preferably
The semi-crystalline chlorinated polyethylene has a crystal residue of 10 J / g or more and 50 J / g or less as measured by differential scanning calorimetry.

[Appendix 7]
In the catalyst batch of Appendix 1, preferably
The polymer (a) (as the polyolefin) contains the linear low-density polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a).

[Appendix 8]
In the catalyst batch of Appendix 7, preferably
The polyolefin contains an ethylene-vinyl acetate copolymer as another polyolefin component of the linear low density polyethylene.

[Appendix 9]
In the catalyst batch of Appendix 8, preferably
The polymer (a) is 10 parts by mass or more and 70 parts by mass or less of the linear low-density polyethylene with respect to 100 parts by mass of the polymer (a), and 30 parts by mass with respect to 100 parts by mass of the polymer (a). The above-mentioned ethylene-vinyl acetate copolymer of 90 parts by mass or more is contained.

[Appendix 10]
In any one of the catalyst batches of Addendums 1 to 9, preferably
In the silane graft polymer (A), the silane compound is 2 parts by mass or more and 6 parts by mass or less with respect to 100 parts by mass of the polymer (a), and the ratio of the silane compound to the free radical generator is 100 or more. Graft-polymerized to be 300 or less,
The silanol condensation catalyst (B) is contained in an amount of 0.03 parts by mass or more and 0.3 parts by mass or less with respect to 100 parts by mass of the polymer (a).

[Appendix 11]
In the catalyst batch of any one of Supplementary note 1 to Supplementary note 10, preferably.
In addition, it contains a flame retardant.

[Appendix 12]
According to another aspect of the invention.
A polymer (a) containing a polyolefin, which is 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 100 parts by mass of the polymer (a). With respect to 100 parts by mass of the polymer (a) containing at least one of linear low-density polyethylene of 10 parts by mass or more and 70 parts by mass or less, 1 part by mass or more of the silane compound and 10 parts by mass or less of the free radical generator. The silane compound is added so that the ratio of the silane compound to the free radical generator is 5 or more and 400 or less, and the silane compound is graft-polymerized in the presence of the free radical generator in the polymer (a) to obtain a silane graft polymer. While forming (A), the silanol condensation catalyst (B) is added to the silane graft polymer (A) so as to be 0.01 part by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a). By doing so, the polymer batch preparation process to obtain the polymer batch and
The catalyst batch and the silane batch containing the silane graft polymer obtained by graft-polymerizing the silane compound on the polymer are mixed in the range of 10:90 to 90:10, and the mixture is extruded so as to cover the outer periphery of the conductor and molded. The extrusion process to get the body and
Provided is a method for manufacturing an electric wire / cable having a cross-linking step of cross-linking the molded product with silane to form a coating layer.

[Appendix 13]
According to still another aspect of the invention.
A conductor and a coating layer arranged on the outer circumference of the conductor are provided.
The coating layer is formed by silane cross-linking a mixture containing a silane batch containing a silane graft polymer graft-polymerized with a silane compound and a catalyst batch in the range of 10:90 to 90:10.
The catalyst batch is
A silane graft polymer (A) in which a silane compound is graft-polymerized in the presence of a free radical generator on a polymer (a) containing polyolefin, and
Containing silanol condensation catalyst (B),
The polymer (a) is a semi-crystalline chlorinated polyethylene of 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a), and 10 parts by mass or more with respect to 100 parts by mass of the polymer (a). Contains at least one of 70 parts by mass or less of linear low density polyethylene.
In the silane graft polymer (A), the silane compound is 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer (a), and the ratio of the silane compound to the free radical generator is 5 or more. Graft-polymerized to 400 or less,
An electric wire / cable containing the silanol condensation catalyst (B) in an amount of 0.01 parts by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a) is provided.

10 Wire 11 Conductor 12 Insulation layer 13 Catalyst batch 14 Silane batch 15 Mixture 20 Cable 21 Conductor 22 Insulation layer 23 Wire 24 Holding tape 25 Sheath

Claims (2)

Crystal melting of the polymer (a) containing a polyolefin, which is 30 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a) and shows a crystal residue obtained by differential scanning calorific value (DSC) measurement. At least one of semi-crystalline chlorinated polyethylene having a calorific value of 10 J / g to 50 J / g and linear low-density polyethylene having a calorific value of 30 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the polymer (a). The mass ratio of the silane compound to 100 parts by mass of the polymer (a) contained is 1 part by mass or more and 10 parts by mass or less, and the mass ratio of the free radical generator to the free radical generator is 5 or more and 400 or less. The silane compound is graft-polymerized on the polymer (a) in the presence of the free radical generator to form a silane graft polymer (A), and at the same time, silanol condensation is carried out on the silane graft polymer (A). A catalyst batch preparation step of obtaining a catalyst batch by adding the catalyst (B) so as to be 0.01 part by mass or more and 1 part by mass or less with respect to 100 parts by mass of the polymer (a).
The catalyst batch and the silane batch containing the silane graft polymer obtained by graft-polymerizing the silane compound on the polymer are mixed in the range of 10:90 to 90:10, and the mixture is extruded so as to cover the outer periphery of the conductor and molded. The extrusion process to get the body and
A method for manufacturing an electric wire / cable, comprising a cross-linking step of cross-linking the molded product with silane to form a coating layer. Said polyolefin, said as another polyolefin component of linear low density polyethylene, ethylene - wire and cable manufacturing method according to claim 1 comprising a vinyl acetate copolymer.

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