JPS60260635A - Radiation-crosslinkable fluororesin composition - Google Patents

Abstract

PURPOSE:The titled composition which gives crosslinked moldings having a good appearance and excellent mechanical characteristics in a high temperature atmosphere, obtained by incorporating neodymium oxide, titanium oxide, and a crosslinking agent into an ethylene-fluoroolefin copolymer. CONSTITUTION:0.05-5pts.wt. neodymium oxide, 0.05-10pts.wt. titanium oxide, and at least 0.5pt.wt. crosslinking agent are incorporated into 100pts.wt. ethylene-fluoroolefin copolymer (e.g. an ethylene-tetrafluoroethylene copolymer or an ethylene-chlorotrifluoroethylene copolymer). If the amount of neodymium oxide is less than 0.05pt.wt., it can not sufficiently control the chemical reaction, nor can it improve the appearance of an extrudate; if more than 10pts.wt., it tends to cause graining due to the flocculation of neodymium oxide. Titanium oxide acts in the same manner as neodymium oxide, and the combined use of the two will produce a greater effect because of synergism.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is directed to a fluororesin crosslinkable molded product that can be crosslinked by irradiation with radiation such as an electron beam, thereby making it possible to obtain a fluororesin crosslinked molded product with excellent mechanical properties in a high-temperature atmosphere. This invention relates to a resin composition.

[Prior art] ■Tyrene-fluoroolefin copolymers generally have particularly excellent mechanical properties and processability among fluororesins, as well as excellent electrical properties, chemical resistance, and heat resistance, and are well-balanced. The material is

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 problem, it is known to perform crosslinking by irradiating radiation such as electron beams, but crosslinking and disintegration are simultaneously performed by irradiation with DA radiation, 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 purpose is to capture the obtained fluorine-containing resin composition.

The fluororesin composition of the present invention contains 0.05 to 5 parts by weight of neodymium oxide, 0.05 to 10 parts by weight of tital oxide, and 0 parts by weight of a crosslinking agent to 100 parts by weight of the ethylene-fluoroolefin copolymer. It is characterized by containing .5 parts by weight or more.

1 [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 be used even if it is in between.

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 the range of 0.2 to 2 parts by weight is particularly preferable.

If it is less than 0.05 part by weight, the action to suppress the above chemical reaction will not be sufficient, and the extruded appearance cannot be improved, and if it is less than 5 mm part, the neodymium oxide will agglomerate, making it easy to form lumps.

Titanium oxide also behaves in the same way as neodymium oxide, but experiments have shown that using both together produces a greater effect due to a synergistic effect.
＃″＞h T 'y' 6・1.(.

The content of titanium oxide needs to be in the range of 0.05 to 10 parts by weight for the same reason as in the case of neodymium oxide.

3- Examples of crosslinking agents include allyl type compounds (compounds containing an allyl group), including triallyl cyanurate-1~, triallyl isocyanurate, triallyl trimellitate, triallyl trimesate, and tetraallyl pyro. Examples include Meritate.

The crosslinking agent must be used in an amount of 0.5 mm part or more per 100 parts by weight of the ethylene-tetrafluoroethylene copolymer; if it is less than this, a molded product with good mechanical properties cannot be obtained in a high-temperature atmosphere. . Usually 1~
The range is 20 parts by weight.

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

[Example] With the mixing ratios of various components as shown on each side of Table 1, the temperature in barrel zone 1 is 260 ° C., and the temperature in barrel zone 2 is 260 ° C.
70℃, barrel zone 3 temperature 4-300℃, crosshead temperature 320℃, die temperature 3
Extruder set at 20°C, screw rotation speed 15 r, rl, I (40 m/ra, L/D = 20. Compression ratio =
3), the outer periphery of a conductor having an outer diameter of 0.8 #I11 was coated by extrusion to a thickness of 0.2 mm, and then irradiated with an electron beam of 10 Mrad to create a crosslinked insulated wire.

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

Note that 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 J15C3005.

Table 1 *1: Asahi Glass Co., Ltd. Avalon C0PC-88A *2: Number of knobs per 1 TrL length *3: Unable to measure due to poor appearance As is clear from Table 1, implementation within the scope of the present invention Example 1
- 4, all had good extrusion appearance, and 300°C
It is difficult to deform even at such high temperatures.

In contrast, Comparative Example 1 in which the amount of neodymium oxide added was less than the minimum specified by the present invention, Comparative Example 2 in which only titanium oxide was added,
Comparative Example 3, which does not contain any of these, has many lumps on the surface and has an inferior extrusion appearance. Comparative Example 4, which does not contain a crosslinking agent, melts at 300°C.

[Effects of the Invention] As explained above, the present invention provides a composition containing neodymium oxide, titanium oxide, and a crosslinking agent in an ethylene-fluoroolefin copolymer. This makes it possible to obtain crosslinked molded products with excellent physical properties and a good appearance, further expanding the fields of use for fluororesins.

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Claims (3)

[Claims] (1) Ethylene-fluoroolefin copolymer 100
Based on the weight part, 0.05 to 5 M parts of neodymium oxide, 0.05 to 10 parts by weight of titanium oxide, and 0 parts of crosslinking agent.
．． A radiation crosslinkable fluororesin composition containing 5 or more heavy chain parts. (2) The ethylene-fluoroolefin copolymer is
The radiation crosslinkable fluororesin composition according to claim 1, which is a tyrene-tetrafluoroethylene copolymer. (3) The radiation crosslinkable fluororesin composition according to claim 1 or 2, wherein the crosslinking material is an allyl type compound.