At present, many manufacturers of PE separators are tackling the key problems in this respect, in order to improve the thermal oxygen aging resistance of the separators. Many manufacturers also put forward some feasible schemes. Such as using more high molecular weight polyethylene, increasing the amount of PE powder and so on. The author does not elaborate.
 

Here only two aspects of the impact on the oxidation resistance of PE separator are discussed.
 

Selection and use of antioxidants: Antioxidants are auxiliary additives for PE separator molding. Although the amount of antioxidants is very small, accounting for about 2% of the total amount of PE powder, they play an important role in the antioxidant performance of PE separator. The main role of antioxidants in the separator is to react with free radicals R #, roo #, interrupt the chain growth of automatic oxidation, and eliminate peroxy free radicals. Roo #, which is the key to prevent the degradation of polymers, is because the elimination of roo #, directly inhibits the formation and decomposition of hydroperoxides. At present, domestic and foreign manufacturers choose different antioxidants. Most of them use antioxidant 300, which is a compound antioxidant. It has the function of both main antioxidant and auxiliary antioxidant, and has a good synergistic effect with the colorant of battery separator, but the price is high.
 

At present, considering the cost of products, some manufacturers are trying to use or use other antioxidants, such as antioxidant 1010 and antioxidant 168. Among them, antioxidant 1010 is the main antioxidant, and antioxidant 168 is the auxiliary antioxidant, with 1? 1.
 

The oxidation induction period of the separator is proportional to the oil content of the separator. The higher the oil content of the separator is, the longer the oxidation induction period is.
 

It can be seen from the data that the oil content plays an important role in the oxidation resistance of the separator.
 

The experiment of oxidation induction period was carried out at 230 ℃!, The stable time of diaphragm was measured in pure oxygen environment. Therefore, to a certain extent, the oxidation induction period reflects the antioxidant aging ability of the separator.