Plastic antioxidants help extend plastic life

With the rapid development of the plastics industry, especially the continuous development and application of various new functional plastics, the global antioxidant industry is developing in the direction of specialization, serialization, compounding, high efficiency and green. In the future, it is important for the domestic key to understand the current trend of antioxidant development and vigorously develop antioxidant varieties suitable for the development of the plastics industry.

Antioxidants are the most widely used additives in plastics. One of the most widely used contents refers to the application of antioxidants in various stages of polymerization, granulation, storage, use and recycling of plastics. The second most widely used content refers to the variety of plastic materials that have emerged in the world today, such as polyethylene, polypropylene, styrenic polymers, engineering plastics, etc., using antioxidants. The largest variety of plastic materials.

Different types of main and auxiliary antioxidants, or antioxidants of the same type and different molecular structure, have different functions and application effects. Commonly used plastic antioxidants are generally classified into five categories according to their molecular structure and mechanism: hindered phenols, Phosphites, thios, complexes, and hindered amines (HALS).

Phosphite antioxidants and sulfur-containing antioxidants are also auxiliary antioxidants. The main mechanism of action of the auxiliary antioxidant is to decompose the highly active hydroperoxide in the plastic into low active molecules. The domestic phosphite antioxidant production consumption accounts for about 30% of the total domestic antioxidant production and consumption. Domestically produced sulfur-containing antioxidants can be classified into thioester antioxidants, thiobisphenol antioxidants, and thioether phenols according to their molecular structure.

The composite antioxidant is compounded by two or more different types or different types of antioxidants. It can be used to complement each other in plastic materials, showing synergistic effect and achieving the best with minimum addition and lowest cost. Anti-thermal aging effect. Synergistic effect means that when two or more kinds of auxiliaries are used in combination, the application effect is greater than the additive effect of each additive alone, that is, 11>2. Antioxidant R&D and production have initially evolved from a general-purpose product line to a combination of general and special purpose; composite antioxidants are increasingly valued by manufacturers; major manufacturers are beginning to trend toward antioxidants and other plastic additives. Serialization development. Some enterprises began to produce raw materials intermediates, forming a production and business model integrating upstream and downstream.

In recent years, not only has domestic production capacity and output increased rapidly, but also new developments, technological advances, and structural adjustments have been made. Special-purpose antioxidants, such as liquid hindered phenol 1135, nitrogen-containing hindered phenol 3114, 1098, semi-hindered phenol Antioxidant 245 and other products have stable production capacity and output; the synthesis of hindered phenol antioxidants and their intermediates uses tin-free catalyst technology, which reduces the heavy metal tin content in phenolic antioxidants and meets environmental protection aspects in foreign countries. Requirements; the hydrolytic stability test of phosphite antioxidant 168 of major production enterprises exceeded the international advanced level. In the future, with the rapid development of the plastics industry, especially the continuous development and application of various new functional plastics, the global antioxidant industry is moving towards high molecular weight, compounding, environmental protection, hydrolysis resistance, high temperature resistance, and more. Functionalization and other directions.