JPH0593116A - Radiation-resistant resin composition - Google Patents

Abstract

PURPOSE:To prepare the title compsn. excellent in radiation resistance and processibility at a low cost by compounding a chlorosulfonated polyethylene with a diphenylamine compd. CONSTITUTION:The title compsn. is prepd. by compounding 100 pts.wt. chlorosulfonated polyethylene with 3-60 pts.wt. diphenylamine compd. (e.g. a compd. of formula I or II). An amt. compounded of the compd. lower than 3 pts.wt. leads to hardening of the compsn. due to decrease in elongation when exposed to a radiation; an amt. higher than 60 pts.wt. results in a bad appearance. T compsn. is free from degradation in finish and has an improved radiation resistance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation-resistant resin composition used as an outer cover or the like of electric wires / cables (hereinafter simply referred to as cables).

[0002]

2. Description of the Related Art A cable used in a radiation environment such as a nuclear power plant is required to have radiation resistance.
In particular, the control cables for manipulator operations for handling nuclear fuel and maintaining the core are exposed to extremely high radiation, and therefore higher radiation resistance is required.

This radiation resistance is mainly borne by an outer sheath (sheath), and as a polymer material for the outer sheath of this type of cable, conventionally, polyetheretherketone has been disclosed in Japanese Utility Model Publication No. 60-84024. (Hereinafter referred to as PEEK) is well known. However, this PEEK is expensive and has a problem of poor workability.

Therefore, it is an object of the present invention to provide a radiation resistant resin composition which has high radiation resistance, is inexpensive, and has excellent processability.

[0005]

In order to solve the above problems, in the present invention, 3 to 60 PHR of a diphenylamine compound is added to 100 parts by weight of chlorosulfonated polyethylene (hereinafter referred to as CSM). That is the structure.

When the amount of the diphenylamine compound is less than the above range, the elongation is lowered and the resin is cured by receiving radiation. On the other hand, if it exceeds the range, the appearance becomes poor.

As the above CSM, Hypalon # 40
(DuPont product name), as diphenylamine compounds, octamine represented by the formula (1) below (trade name manufactured by Nisseki Calcium Co., Ltd.) and Noward 445 represented by the formula (2) (manufactured by Uniroyal Corp.) Product name) etc. can be mentioned respectively.

[0008]

[Chemical 1]

[0009]

[Chemical 2]

[0010]

In the resin composition according to the present invention having the above-mentioned constitution, the radiation resistance is improved by the addition of the required amount of the diphenylamine compound.

[0011]

[Examples] Examples 1 to 1 with the compounding ratio (parts by weight) shown in Table 1
4 and the resin compositions of Comparative Examples 1 to 3 were kneaded and prepared. The kneading was carried out by first kneading with a 150 mmφ test roll without kneading the cross-linking agent at 120 ° C. for 20 minutes, then as the second kneading, lowering the temperature to 50 ° C. and adding the cross-linking agent. And kneaded for 10 minutes.

The resin composition thus obtained has a thickness of 1 mm,
Inner dimensions: 15mm x 150mm, put in a metal frame, 15
After press-crosslinking at 0 kgf / cm ² × 150 ° C. × 30 minutes,
After pressure cooling, a test sheet having a thickness of 1 mm × a length of 150 mm × a width of 150 mm was obtained.

Looking at the finished appearance of this sheet,
Each dose of γ-ray ( ⁶⁰ Co as a radiation source, dose rate 0.8 MR /
hr. The lower column of Table 1 shows the results of measuring the elongation (El) and the tensile strength (Ts) in air (at room temperature). In the table,
The units of El and Ts are%, kg / mm ² , circles are good,
X indicates a defect (significant unevenness of the appearance of the sheet), blank indicates that measurement is impossible, and "original" indicates that no γ-ray irradiation is performed. Tensile test according to JIS K0301, pulling speed 2
It was performed at 00 mm / min.

[0014]

[Table 1]

From the test results, it can be understood that the resin composition according to the present invention is excellent in finish and radiation resistance in the specific blending ratio. Therefore, it can be sufficiently satisfied as an insulation coating for radiation-resistant electric wires and cables.

[0016]

Since the present invention is constructed as described above, the radiation resistance is improved without deteriorating the finishability.

Claims (1)

[Claims] 1. A radiation resistant resin composition obtained by adding 3 to 60 PHR of a diphenylamine compound to 100 parts by weight of chlorosulfonated polyethylene.