JP2018090703A - Method for producing resin composition and method for producing insulated wire using resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a resin composition in which chlorinated polyethylene and an ethylene α olefin copolymer are made compatible with each other, and the occurrence of aggregate is prevented.SOLUTION: A method for producing a resin composition includes the steps of mixing chlorinated polyethylene, an ethylene α olefin copolymer and carbon black to obtain masterbatch for resin molding, and of mixing the obtained masterbatch for resin molding further with an ethylene α olefin copolymer to obtain the resin composition.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a resin composition obtained by mixing chlorinated polyethylene and an ethylene α-olefin copolymer, and a method for producing an insulated wire using such a resin composition.

  Talc is used as a base polymer in which chlorinated polyethylene, which is a resin with excellent flame retardancy, and a copolymer of ethylene and α-olefin (hereinafter referred to as ethylene α-olefin copolymer) is used as an insulation material or sheath material for electric wires. A resin composition to which a filler such as carbon black is added is used (for example, see Patent Document 1). Such a resin composition is manufactured by charging all raw materials constituting the resin composition such as a base polymer and a filler into a hopper in an extruder and kneading and extruding them.

  On the other hand, since the chlorinated polyethylene and the ethylene α-olefin copolymer are remarkably different in viscosity, they have a poor compatibility and easily form an aggregate. In order to avoid the formation of such aggregates, a method of increasing the kneading speed of the extruder can be considered.

JP-A-5-81933

  However, in the method of increasing the kneading speed, the resin composition being kneaded causes self-heating, which causes dehydrochlorination of the chlorinated polyethylene, and instead the viscosity of the chlorinated polyethylene increases. Aggregates containing chlorinated polyethylene as the main component may be present.

  Moreover, when an insulating layer is formed by extrusion onto a conductor using such a resin composition, an appearance defect due to unevenness may be caused on the surface of the insulator.

  Therefore, the present invention has been made in view of the above problems, and aims to provide a method for producing a resin composition in which chlorinated polyethylene and an ethylene α-olefin copolymer are compatible with each other and generation of aggregates is reduced. To do.

  Another object of the present invention is to provide a method for producing an insulated wire having a good appearance by reducing the generation of aggregates during the kneading step.

  In order to achieve the above object, the present invention provides the following adhesive film and flat cable.

[1] A step of mixing a chlorinated polyethylene, an ethylene α-olefin copolymer, and carbon black to obtain a resin molding masterbatch, and further adding an ethylene α-olefin copolymer to the obtained resin molding masterbatch. And a step of mixing to obtain a resin composition.
[2] In a method for producing an insulated wire having an insulating layer formed by extrusion coating a resin composition on the outer periphery of a conductor, a master for resin molding by mixing chlorinated polyethylene, ethylene α-olefin copolymer and carbon black A step of obtaining a batch, a step of further adding an ethylene α-olefin copolymer to the obtained master batch for resin molding, and a step of obtaining a resin composition, and extrusion coating the outer periphery of the conductor with the resin composition A process for producing an insulated wire, comprising:

  According to the method for producing a resin composition of the present invention, chlorinated polyethylene and an ethylene α-olefin copolymer are compatible with each other, and the generation of aggregates can be reduced. Moreover, according to the manufacturing method of the insulated wire of this invention, the manufacturing method of the insulated wire which has the favorable external appearance which reduced generation | occurrence | production of the aggregate at the time of a kneading | mixing process can be provided.

  Hereinafter, an embodiment of the present invention will be described.

[Method for producing resin composition]
First, a method for producing a resin composition of the present embodiment includes a step of mixing a chlorinated polyethylene, an ethylene α-olefin copolymer, and carbon black to obtain a resin molding master batch, and the obtained resin molding master batch. And a step of mixing an ethylene α-olefin copolymer to obtain a resin composition.

  That is, the process of kneading the chlorinated polyethylene and the ethylene α-olefin copolymer is divided into a plurality of steps into a master batch, thereby sufficiently compatibilizing the chlorinated polyethylene and the ethylene α-olefin copolymer. In addition, in the process of obtaining a master batch for resin molding, by mixing a predetermined amount of carbon black, the heat generated by the self-heating of the mixture during kneading is dissipated by heat conduction by carbon black, and the temperature rise is suppressed. Therefore, the generation of aggregates during the kneading step can be reduced.

  The step of obtaining a master batch for a resin composition in the method for producing a resin composition of the present embodiment comprises mixing chlorinated polyethylene, an ethylene α-olefin copolymer, and carbon black.

(Chlorinated polyethylene)
For chlorinated polyethylene, the particle size is not particularly limited, but when creating a graph that falls to the right with the particle size distribution as a cumulative distribution, the horizontal axis is the particle size and the coarse particle side is zero In addition, the chlorinated polyethylene according to the present embodiment preferably uses particles having no coarse particles of 1100 μm or more and particles having a cumulative distribution 20% (D20) of 700 μm or less. This is because according to the knowledge of the present inventors, it is considered that aggregates tend to be remarkably generated when the above-described particles are used. An example of such particles is CM3685 manufactured by Chemical Inspection & Regulation Service.

  The chlorination degree of chlorinated polyethylene is preferably 20 to 40%. The content of the chlorinated polyethylene in the base polymer is preferably 20 parts by mass or more and 60 parts by mass or less with respect to 100 parts by mass of the base polymer.

(Ethylene α-olefin copolymer)
As the ethylene α-olefin copolymer of the present embodiment, for example, a copolymer composed of ethylene and an α-olefin having 3 to 8 carbon atoms can be used. Among these, an ethylene vinyl acetate copolymer can be used. Moreover, it is preferable that the content rate in the base polymer of an ethylene alpha olefin copolymer is 10 to 50 mass parts with respect to 100 mass parts of base polymers.

(Carbon black)
The carbon black of the present embodiment has a function of dissipating heat generated by self-heating of the mixture during kneading and suppressing the temperature rise of the mixture to reduce the generation of aggregates during the kneading process. It is used in the process of obtaining a master batch. The content ratio of carbon black to 100 parts by mass of the base polymer is preferably 20 parts by mass or more and 40 parts by mass or less. Although the kind of carbon black is not particularly limited, for example, MT carbon can be used.

  In the step of obtaining the resin molding masterbatch of this embodiment, it is preferable to obtain a resin molding masterbatch by kneading chlorinated polyethylene, ethylene α-olefin copolymer and carbon black using an extruder. The extruder and the like are not particularly limited in structure, and a twin-screw continuous extruder, a Banbury mixer, a pressure kneader, or the like can also be used. For example, when manufacturing a master batch for resin molding with a Banbury mixer, kneading while cooling with water, followed by extrusion granulation with a single screw extruder, pelletizing, and again using a Banbury mixer or a twin screw continuous extruder It is possible to produce a composition.

  Further, in order to suppress the temperature rise of the resin due to self-heating during kneading, it is desirable to knead while cooling with water to keep the resin temperature at 180 ° C. or lower.

  Further, in the step of obtaining the resin molding masterbatch of the present embodiment, in addition to chlorinated polyethylene, ethylene α-olefin copolymer and carbon black, as long as the effects of the present invention are exhibited, a plasticizer, an antioxidant Various additives such as a lubricant, a lubricant, a flame retardant, and a stabilizer can be blended.

  The step of obtaining a resin composition in the method for producing a resin composition of the present embodiment comprises further mixing an ethylene α-olefin copolymer with the obtained resin molding masterbatch.

  The kind of ethylene α-olefin copolymer used in the step of obtaining the resin composition can be the same as the ethylene α-olefin copolymer used in the step of obtaining the resin molding masterbatch. Moreover, it is preferable that the content rate of an ethylene alpha olefin copolymer is 50 mass parts or more and 100 mass parts or less with respect to 100 mass parts of master batches for resin molding. Moreover, the point which can mix | blend various additives other than an ethylene alpha olefin copolymer is the same as the process of obtaining the masterbatch for resin molding. For example, a filler such as talc can be blended in an amount of 10 parts by mass to 30 parts by mass with respect to 100 parts by mass of the resin molding master batch.

  Also about the process of obtaining a resin composition, it can manufacture using the extruder used in the process of obtaining the masterbatch for resin molding.

  EXAMPLES Next, although this invention is demonstrated in detail based on an Example, this invention is not limited to these Examples.

Carbon black (MT carbon) with respect to 100 parts by mass of a base polymer consisting of 80 parts by mass of powdered chlorinated polyethylene (trade name CM3685) and 20 parts by mass of a pellet-like ethylene vinyl acetate copolymer (trade name EVA260) ) A mixture consisting of 30 parts by mass and 6 parts by mass of a flame retardant (antimony trioxide) was introduced into a water-cooled twin-screw continuous extruder having a screw diameter of 87 mm and a jacket structure in the cylinder, and the screw rotation speed was 30 to 60 rpm. The mixture was kneaded while adjusting to the above range to obtain a master batch for resin molding.
Subsequently, a mixture of 82 parts by mass of an ethylene vinyl acetate copolymer (trade name EVA260) and 14 parts by weight of talc (trade name High Filler # 16) with respect to 100 parts by mass of the resin molding masterbatch was subjected to the biaxial continuous extrusion. A resin composition was obtained by kneading using an extruder of the same type as the machine.
This resin composition was coated on a stranded wire conductor having a diameter of 1 mm to a thickness of 1 mm to form an insulating layer, thereby obtaining an insulated wire.

About the obtained insulated wire, the confirmation and external appearance of the aggregate were evaluated as follows.
(Confirmation of aggregates)
The presence or absence of aggregates was confirmed by confirming the cross section of the insulating layer of the obtained insulated wire. When an aggregate was confirmed, it was judged as bad, and when no aggregate was confirmed, it was judged as good.

(Appearance evaluation)
Moreover, the external appearance of the insulated wire confirmed the presence or absence of an unevenness | corrugation by touching the surface of an insulated wire. When irregularities were confirmed by palpation, it was judged as bad, and when it was not confirmed, it was judged as good.
As a result, in the above examples, no aggregate was confirmed, and the appearance was good.

Claims (2)

A step of mixing a chlorinated polyethylene, an ethylene α-olefin copolymer and carbon black to obtain a resin molding masterbatch;
A process for producing a resin composition, further comprising a step of mixing an ethylene α-olefin copolymer with the obtained master batch for resin molding to obtain a resin composition In the method of manufacturing an insulated wire having an insulating layer formed by extrusion coating the resin composition on the outer periphery of the conductor,
A step of mixing a chlorinated polyethylene, an ethylene α-olefin copolymer and carbon black to obtain a resin molding masterbatch;
A step of further adding an ethylene α-olefin copolymer to the obtained resin molding masterbatch to obtain a resin composition;
And a step of extrusion-coating the resin composition on an outer periphery of the conductor.