JPH0131776B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to anti-aging agents, and more particularly to anti-aging agents that are extremely effective against organic polymeric substances. [Prior art] Olefin polymers, especially ethylene polymers, have excellent electrical insulation properties, and various crosslinking methods such as radiation crosslinking, organic peroxide crosslinking, and crosslinking using silane compounds can be appropriately employed. Since crosslinking has the advantage of improving various physical properties, it has been widely used in various fields including electrical insulation materials. Recently, in various fields such as electrical equipment, vehicles, and automobiles, insulated wires, especially electronic wires, have been required to have more advanced properties, especially those with higher anti-aging properties than conventional ones. There has been a strong demand for significantly superior anti-aging properties. [Object of the Invention] The present inventor has been paying attention to the above-mentioned drawbacks of the above-mentioned olefin-based polymers, and has conducted intensive research in order to develop an olefin-based polymer composition, particularly an ethylene-based polymer composition, that has extremely excellent aging resistance. As mentioned above, in this research, when two specific compounds are used together as an anti-aging agent, the synergistic effect of these two specific compounds results in a remarkable anti-aging effect. We found that these two specific types of anti-aging agents have a significantly superior anti-aging effect not only on olefin polymers but also on other organic polymer substances due to their excellent synergistic effects. It was discovered that the present invention exhibits preventive properties, and based on these new facts, the present invention was completed. That is, the present invention includes 100 parts by weight of benzimidazole and N,
N'-hexamethylene-bis(3,5-di-t-
Butyl-4-hydroxy-hydrocinnamide) 1
This relates to an antiaging agent for organic polymers containing ~500 parts by weight. The above hydrocinnamide has the following structural formula. [Effect of the invention] In the present invention, benzimidazole and N,N'-hexamethylene-bis(3,5-di-
By using two specific compounds called t-butyl-4-hydroxy-hydrocinnamide (hereinafter simply referred to as hydrocyanamide) in the specific proportions as described above, the combination of these two compounds can be achieved as shown in the examples below. Demonstrates outstanding anti-aging properties through synergistic action. This anti-aging property is exhibited by a wide range of organic polymer compounds, but is particularly noticeable by olefinic polymers. Furthermore, when using the above-mentioned benzimidazole and hydrocyanamide together, by further using an anti-aging substance containing nitrogen or sulfur atoms as a third component, the synergistic effect of these compounds will further prevent aging. It has the effect of making the performance even better. [Structure of the Invention] The present invention is basically an anti-aging agent containing 100 parts by weight of benzimidazole and 1 to 500 parts by weight of hydrocyanamide, and this basic anti-aging agent further contains nitrogen or sulfur atoms. This anti-aging agent contains other anti-aging substances as a third component. The ratio of benzimidazole and hydrocyanamide of the present invention is 1 to 500 parts by weight, preferably 2 to 200 parts by weight, more preferably 5 parts by weight to 100 parts by weight of the former.
~100 parts by weight, and if the latter does not reach 1 part by weight, it is difficult to fully exhibit the synergistic effect of the two. Further, in the present invention, the anti-aging substance containing nitrogen or sulfur atoms which is further used as a third component in combination with the above two types of compounds is benzimidazole 100.
The amount used is about 1 to 100 parts by weight, preferably about 5 to 20 parts by weight. In addition, examples of these anti-aging substances include lauryl dithiopropionate,
Preferred specific examples include melamine and the like. The anti-aging agent of the present invention can be used for various organic polymer substances, but is particularly preferably used for olefinic polymers. In this case, the olefinic polymers include a wide range of homopolymers or copolymers of ethylene, propylene, butylene, 4-methylpentene-1, etc., but ethylene homopolymers or copolymers are preferred. I can do it. As the ethylene homopolymer in this case, ordinary polyethylene can be used, but it is more preferably linear and low density, for example, one with a density of about 0.92 g/cm ³ is preferred. Examples of copolymers of ethylene include copolymers with other monomers that can be copolymerized with ethylene, such as ethylene-vinyl acetate copolymer (EVA) and ethylene-ethyl acrylate copolymer (EEA). ), ethylene-propylene copolymer, etc. The amount of the anti-aging agent of the present invention to be used varies depending on the type of organic polymer substance used, its use, etc., but usually 0.5 to 20 parts by weight of the anti-aging agent of the present invention is preferably 1 part by weight per 100 parts by weight of the organic polymer substance. ~10 parts by weight are used. EXAMPLES The present invention will be explained in more detail with reference to Examples below. However, in the following examples, "parts" means parts by weight. Example 1 A composition was prepared by sufficiently kneading the mixture at the predetermined mixing ratios shown in Tables 1 and 2. The heat aging resistance and the aging resistance in the presence of copper of this composition were measured. The results are shown in Table 3. However, for those subjected to irradiation crosslinking, the crosslinking was carried out at 20 Mrad using an electron beam analyzer. <Heat aging resistance> The composition was pressed into a sheet with a thickness of 1 mm, and this was
Heat deterioration was performed according to JIS K 6723, and the number of days of deterioration when the absolute value of elongation reached 50% was measured. <Aging properties in the presence of copper damage> A copper wire is coated with the composition according to a conventional method to form an electric wire, and after aging by exposing the electric wire to a predetermined high temperature, the composition is coated with the composition by self-diameter winding at room temperature. The time required for the crack to occur was measured.

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Claims (1)

[Claims] 1. 100 parts by weight of benzimidazole and N, N'--
Hexamethylene-bis(3,5-di-t-butyl-4-hydroxy-hydrocinnamide) 1-500
An anti-aging agent for organic polymers containing parts by weight. 2. The anti-aging agent for organic polymers according to claim 1, which further contains an anti-aging substance having nitrogen or sulfur atoms (excluding those described in claim 1 above). agent.