JPS60260634A - Radiation-crosslinkable fluorocarbon resin composition - Google Patents

Abstract

PURPOSE:A fluorocarbon resin composition which can give a crosslinked molding having a good appearance and excellent mechanical properties in a high- temperature atmosphere, prepared by adding neodymium oxide and a crosslinking agent to an ethylene/fluoro-olefin copolymer. CONSTITUTION:0.05-10pts.wt. neodymium oxide and 0.5pt.wt. or above crosslinking agent are added to 100pts.wt. ethylene/fluoro-olefin copolymer. Examples of the ethylene/fluoro-olefin copolymers used include ethylene/tetrafluoroethylene copolymers and ethylene/chlorotrifluoroethylene copolymers. When the amount of neodymium oxide added is below 0.05pt.wt., the function of controlling a chemical reaction is not sufficient, and the appearance of an extrusion can not be improved. When this amount is above 10pts.wt., specks are readily formed because of the coagulation of neodymium oxide. Examples of the crosslinking agents used include triallyl cyanurate and tetraallyl pyromellitate.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a method for obtaining a crosslinked fluororesin molded product with excellent mechanical properties in a high-temperature atmosphere by irradiation with radiation such as an electron beam. The present invention relates to a crosslinkable fluororesin composition.

[Prior art] Ethylene-fluoroolefin copolymers generally have excellent mechanical properties and processability among fluororesins, as well as excellent electrical properties, chemical resistance, and heat resistance, and have a well-balanced property. It is the material.

For this reason, it is used in various fields, including as a material for covering electric wires, as well as in the form of films and tubes.

However, when placed in a high-temperature atmosphere that exceeds the melting point, it deforms due to external force, and there is a limit to its use at high temperatures.

In order to improve this, it is known to perform crosslinking by irradiating with radiation such as an electron beam, but crosslinking and disintegration occur simultaneously due to radiation irradiation, making it impossible to achieve sufficient crosslinking efficiency.

Therefore, attempts have been made to improve the crosslinking efficiency by adding a crosslinking agent such as an allyl type compound.

[Problems to be Solved by the Invention] However, if a crosslinking agent is simply added and extrusion molded, the crosslinking agent and fluororesin will decompose due to extrusion at high temperatures and local agglomeration, etc. There is a problem in that this causes a reaction and the appearance of the molded product becomes rough, making it impossible to obtain a good product.

[Means for Solving the Invention] The present invention has been made using the above, and provides a molded product that can obtain a molded product having a good appearance and has excellent mechanical properties in a high-temperature atmosphere. The object of the present invention is to provide a sulfur-containing resin composition that can be obtained.

The fluororesin composition of the present invention is characterized by containing 0.05 to 10 parts by weight of neodymium oxide and 0.5 parts by weight or more of a crosslinking agent based on 100 parts by weight of the ethylene-fluoroolefin copolymer. It is something to do.

[Function] In the present invention, examples of the ethylene-fluoroolefin copolymer include ethylene-tetrafluoroethylene copolymer and ethylene-chlorotrifluoroethylene copolymer, which may be used alone or in combination of two or more. It can also be used.

Neodymium oxide has the function of suppressing the chemical reaction between the ethylene-fluoroolefin copolymer and the crosslinking agent, and the amount added is 0.05 to 10 parts by weight per 100 parts by weight of the ethylene-fluoroolefin copolymer. It is necessary to make it into parts by weight, and a range of 0.2 to 2 parts by weight is particularly preferable.

If it is less than 0.05 parts by weight, the effect of suppressing the above chemical reaction will not be sufficient, and the extrusion appearance cannot be improved, and if it is more than 10 parts by weight, it will be easy to form lumps due to agglomeration of neodymium oxide.

Examples of crosslinking agents include allyl type compounds (compounds containing an allyl group) such as triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate,
Examples include triallyl trimesate and tetraallyl pyromellitate. (The crosslinking agent must be used in an amount of 0.5 parts by weight or more per 100 parts by weight of the ethylene-tetrafluoroethylene copolymer, and if it is less than this, good mechanical properties may not be obtained in a high-temperature atmosphere.) It is not possible to obtain a molded product with a 1 to 20 parts.

In the present invention, in addition to the above components, inorganic fillers,
A coloring agent or the like may be added, or a te]-rafluoroethylene-propylene copolymer, polyvinylidene butt, etc. may be blended.

[Example] Various components were mixed in the proportions shown in Table 1, and the temperature in barrel zone 1 was 260°C, and the temperature in barrel zone 2 was 260°C.
70°C, barrel zone 3 temperature 300°C, crosshead temperature 320°C, die temperature 320°C, screw rotation speed 15 r, 11. Extruder set at 40m/m
, L/D=20. Compression ratio = 3), outer diameter 0.8m
The outer periphery of the conductor was coated by extrusion to a thickness of 0.2 tntn, and then an electron beam of 10 Mrad was irradiated to create a crosslinked U-ray.

The reputation results for each insulated wire are shown in the lower column of Table 1.

4- The appearance after extrusion is the result of visually observing the appearance of the insulated wire, and the heat deformation rate is the result of measurement at 300°C in accordance with JISC3005.

Table 1 *2: Number of protrusions per 1 TrL of length *3: Unable to measure due to poor appearance As is clear from Table 1, Example 1 within the scope of the present invention
- 4, all had good extrusion appearance, and 300°C
It is difficult to deform even at such high temperatures.

On the other hand, in Comparative Example 1 in which the amount of neodymium oxide added was less than the amount specified in the present invention, Comparative Example 2 in which it exceeded the specified amount, and Comparative Example 3 in which it was not added at all, there were many lumps on the surface and the extruded appearance was poor. Comparative Example 4, which does not contain a crosslinking agent, melts at 300°C.

"Effects of the Invention J and Below" - As explained above, the present invention provides a composition containing neodymium oxide and a crosslinking agent in an ethylene-fluoroolefin copolymer, and thereby,
It becomes possible to obtain crosslinked molded products with excellent mechanical properties at high temperatures and a good appearance, further expanding the fields of use of fluororesins.

Claims (3)

[Claims] (1) Ethylene-fluoroolefin copolymer 100
A fluororesin composition capable of crosslinking by radiation, comprising 0.05 to 10 parts by weight of neodymium oxide and 0.5 parts by weight or more of a weight forming agent. (2) The radiation crosslinkable fluororesin composition according to claim 1, wherein the ethylene-fluoroolefin copolymer is an ethylene-tetrafluoroethylene copolymer. (3) The radiation crosslinkable fluororesin composition according to claim 1 or 2, wherein the crosslinking material is an allyl type compound.