The antioxidant activity of amine compounds for plastic masterbatches is generally greater than that of phenolic compounds, so they should have better antioxidant properties. However, amine compounds will change color under the action of oxygen and light in the air, and they are mostly It is colored and toxic, so it is not often used in the plastics industry.

Attention should be paid to the synergistic effect in the application of antioxidants. The following rules can be followed:

1. Combining primary and secondary antioxidants can produce the strongest synergistic effect.

2. The combined use of main antioxidants is a combined system of free radical traps with the same antioxidant mechanism but different activities. The principle is that the H atom on the weaker radical trapping agent is continuously transferred to the stronger radical trapping group, so that the H atom concentration of the latter during the oxidation process remains unchanged, and the free radical trapping can be fully utilized. Antioxidant effect of aggregating agent.

3. Antioxidant and carbon black are used together. The effectiveness of most amine and phenolic antioxidants decreases significantly in the presence of carbon black, which may be because carbon black directly catalyzes the oxidation of antioxidants and increases the rate of antioxidant consumption. The compounds containing sulfide bonds have a synergistic effect on carbon black, which is also related to the special chemical structure of carbon black.

4. Antioxidant and ultraviolet absorber are used together, which is a stable system with light resistance, heat resistance and oxygen aging. The combination of ultraviolet absorbers eliminates the active products formed by antioxidants during light exposure and protects sulfides from decomposition.